SLUDGE LANCE FOR CLEANING A STEAM GENERATOR

Abstract

A sludge lance system for cleaning a tube bundle of a steam generator is disclosed. The sludge lance system comprises a mount, an index drive, and a sludge lance comprising a longitudinal rail, a manifold, an oscillator assembly, and a distal head. The oscillator assembly comprises a rotary output shaft. The distal head comprises a body portion, a first nozzle body on a first side of the distal head, and a second nozzle body on a second side of the distal head opposite the first side. The first nozzle body is rotatable relative to the body portion about a first longitudinal axis in a first direction in response to a rotation of the rotary output shaft. The second nozzle body is rotatable relative to the body portion about a second longitudinal axis in a second direction opposite the first direction in response to the rotation of the rotary output shaft.

Claims

1. A sludge lance system for cleaning a tube bundle of a steam generator, wherein the steam generator comprises at least one hand hole opening which provides access to an elongate central tube lane within the tube bundle, wherein the elongate central tube lane defines a longitudinal axis, wherein said sludge lance system comprises: a mount positioned outside the steam generator; an index drive supported by the mount; and a sludge lance movable along the longitudinal axis of the elongate central tube lane by the index drive, wherein the sludge lance comprises: a proximal end; a distal end; a longitudinal rail; a manifold extending proximally from the longitudinal rail; an oscillator assembly extending from the manifold, wherein the oscillator assembly comprises a rotary output shaft; and a distal head extending distally from the longitudinal rail, wherein the distal head comprises: a body portion; a first nozzle body positioned on a first lateral side of the body portion, wherein the first nozzle body comprises a first plurality of nozzles, and wherein the first nozzle body is rotatable relative to the body portion about a first longitudinal axis in a first direction in response to a rotation of the rotary output shaft of the oscillator assembly; and a second nozzle body positioned on a second lateral side of the body portion opposite the first lateral side, wherein the second nozzle body comprise a second plurality of nozzles, wherein the second nozzle body is rotatable relative to the body portion about a second longitudinal axis in a second direction in response to the rotation of the rotary output shaft of the oscillator assembly, and wherein the second direction is opposite the first direction.

2. The sludge lance system of claim 1, wherein each of the plurality of first nozzles are to emit fluid along a first flow path, wherein each of the plurality of second nozzles are to emit fluid along a second flow path, and wherein the first flow paths and the second flow paths are mirrored about a central vertical plane of the distal head.

3. The sludge lance system of claim 2, wherein rotation of the first nozzle body and the second nozzle body is synchronized to maintain the first flow paths and the second flow paths mirrored about the central vertical plane.

4. The sludge lance system of claim 1, wherein the sludge lance is solely supported by the mount and the index drive.

5. The sludge lance system of claim 1, wherein the sludge lance is a cantilever sludge lance supported by the mount and the index drive.

6. The sludge lance system of claim 1, wherein the sludge lance is unsupported at the distal end.

7. The sludge lance system of claim 1, wherein the index drive is operably engaged with the rail and prevents horizontal and vertical movement of the rail, and wherein the index drive is to advance the distal head along the elongate central tube lane by advancing the rail along the longitudinal axis.

8. The sludge lance system of claim 1, wherein the index drive comprises a plurality of first rollers engaged with a top face of the rail and a plurality of second rollers engaged with a bottom face of the rail, and wherein the plurality of first rollers and the plurality of second rollers are to advance the distal head along the elongate central tube lane by advancing the rail along the longitudinal axis.

9. The sludge lance system of claim 1, wherein the rail comprises a first drive shaft operably engaged with the first nozzle body and a second drive shaft operably engaged with the second nozzle body, and wherein the first drive shaft and the second drive shaft are operably engaged with the rotary output shaft of the oscillator assembly.

10. The sludge lance system of claim 9, wherein the manifold comprises a transmission to convert the rotation of the rotary output shaft of the oscillator assembly to rotation of the first drive shaft and the second drive shaft in opposite directions.

11. The sludge lance system of claim 9, wherein the first drive shaft and the second drive shaft of the rail are rotationally lockable relative to the rail prior to attaching the rail to the manifold during assembly of the sludge lance.

12. The sludge lance system of claim 11, wherein the first drive shaft and the second drive shaft are rotationally unlocked upon attachment to the manifold during assembly of the sludge lance.

13. A sludge lance system for cleaning a tube bundle of a steam generator, wherein the steam generator comprises at least one hand hole opening which provides access to an elongate central tube lane within the tube bundle, wherein the elongate central tube lane defines a longitudinal axis, wherein said sludge lance system comprises: a mount positioned outside the steam generator; an index drive supported by the mount; and a sludge lance movable along the longitudinal axis of the elongate central tube lane by the index drive, wherein the sludge lance comprises: a proximal end; a distal end; a longitudinal rail; and a distal head extending distally from the longitudinal rail, wherein the distal head comprises: a body portion defining a central vertical plane; a first nozzle body positioned on a first lateral side of the central vertical plane, wherein the first nozzle body comprises a first plurality of nozzles, and wherein the first nozzle body is rotatable relative to the body portion about a first longitudinal axis; and a second nozzle body positioned on a second lateral side of the central vertical plane opposite the first lateral side, wherein the second nozzle body comprise a second plurality of nozzles, wherein the second nozzle body is rotatable relative to the body portion about a second longitudinal axis, wherein each of the plurality of first nozzles are to emit fluid along a first flow path, wherein each of the plurality of second nozzles are to emit fluid along a second flow path, and wherein the first flow paths and the second flow paths are mirrored about the central vertical plane.

14. The sludge lance system of claim 13, wherein rotation of the first nozzle body and the second nozzle body is synchronized to maintain the first flow paths and the second flow paths mirrored about the central vertical plane.

15. The sludge lance system of claim 13, wherein the sludge lance is solely supported by the mount and the index drive.

16. The sludge lance system of claim 13, wherein the sludge lance is unsupported at the distal end.

17. The sludge lance system of claim 13, wherein the index drive is operably engaged with the rail and prevents horizontal and vertical movement of the rail, and wherein the index drive is to advance the distal head along the elongate central tube lane by advancing the rail along the longitudinal axis.

18. The sludge lance system of claim 13, wherein the sludge lance further comprises an oscillator assembly, wherein the rail comprises a first drive shaft operably engaged with the first nozzle body and a second drive shaft operably engaged with the second nozzle body, and wherein the first drive shaft and the second drive shaft are operably engaged with a rotary output shaft of the oscillator assembly.

19. The sludge lance system of claim 18, wherein the first nozzle body and the second nozzle body are rotatable in opposite directions about their longitudinal axes in response to a rotation of the rotary output shaft of the oscillator assembly.

20. The sludge lance system of claim 18, wherein at least one of the first drive shaft and the second drive shaft is rotationally lockable relative to the rail.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Various features of the aspects described herein are set forth with particularity in the appended claims. The various aspects, however, both as to organization and methods of operation, together with advantages thereof, may be understood in accordance with the following description taken in conjunction with the accompanying drawings as follows:

[0011] FIG. 1 is a partial cross section view of a steam generator comprising a plurality of tubes arranged within a tube bundle;

[0012] FIG. 2 is a plan view of a sludge lance system for use with the steam generator of FIG. 1, illustrating a sludge lance of the sludge lance system passing through a hand hole in the steam generator;

[0013] FIG. 3 is an elevation side view of the sludge lance system of FIG. 2;

[0014] FIG. 4 is an elevation side view of a head assembly of the sludge lance of FIG. 2;

[0015] FIG. 5 is a front side view of the head assembly of FIG. 4;

[0016] FIG. 6 is a back side view of the head assembly of FIG. 4;

[0017] FIG. 7 is a cross section view of the head assembly of FIG. 4 taken along line 7-7 in FIG. 6, illustrating a plurality of nozzles of the head assembly oriented horizontally;

[0018] FIG. 8 is a cross section view of the head assembly of FIG. 4 taken along line 8-8 in FIG. 6;

[0019] FIG. 9 is a cross section view of the head assembly of FIG. 4 taken along line 9-9 in FIG. 6, illustrating the plurality of nozzles of the head assembly oriented in a downward direction;

[0020] FIG. 10 is a cross section view of the head assembly of FIG. 4 taken along line 10-10 in FIG. 6;

[0021] FIG. 11 is an elevation view of one half of a split ring needle roller bearing with the rollers of the bearing removed for illustration purposes;

[0022] FIG. 12 is a cross section view of the split ring needle roller bearing of FIG. 11 taken along line 12-12 in FIG. 11;

[0023] FIG. 13 is a cross section view of the split ring needle roller bearing of FIG. 11 taken along line 13-13 in FIG. 11;

[0024] FIG. 14 is a side elevation view of a rail of the sludge lance of FIG. 2;

[0025] FIG. 15 is a front side view of the rail of FIG. 14;

[0026] FIG. 16 is a back side view of the rail of FIG. 14;

[0027] FIG. 17 is a plan view of the rail of FIG. 14;

[0028] FIG. 18 is a cross section view of the rail of FIG. 14 taken along line 18-18 in FIG. 16, illustrating a flow port extending longitudinally through the rail;

[0029] FIG. 19 is a cross section view of the rail of FIG. 14 taken along line 19-19 in FIG. 16;

[0030] FIG. 20 is a cross section view of the rail of FIG. 14 taken along line 20-20 in FIG. 16, illustrating a rail drive shaft rotationally locked to the rail by a lock mechanism;

[0031] FIG. 21 is a cross section view of the rail of FIG. 20 taken along line 21-21 in FIG. 20;

[0032] FIG. 22 is another cross section view of the rail of FIG. 20 with the lock mechanism in an unlocked state which permits the rail drive shaft to rotate relative to the rail;

[0033] FIG. 23 is a cross section view of the rail of FIG. 22 taken along line 23-23 in FIG.

[0034] FIG. 24 is a perspective view of the lock mechanism of FIG. 20;

[0035] FIG. 25 is a cross section view of the lock mechanism of FIG. 24;

[0036] FIG. 26 is a plan view of the sludge lance of FIG. 2 with one rail installed between the head assembly and an oscillator manifold, further illustrating an oscillator assembly attached to the oscillator manifold;

[0037] FIG. 27 is a back side view of the sludge lance of FIG. 26;

[0038] FIG. 28 is a side elevation view of the sludge lance of FIG. 26;

[0039] FIG. 29 is a cross section view of the sludge lance of FIG. 26 taken along line 29-29 in FIG. 28;

[0040] FIG. 30 is a cross section view of the sludge lance of FIG. 26 taken along line 30-30 in FIG. 26;

[0041] FIG. 31 is a cross section view of the sludge lance of FIG. 26 taken along line 31-31 in FIG. 28;

[0042] FIG. 32 is a cross section view of the sludge lance of FIG. 26 taken along line 32-32 in FIG. 26;

[0043] FIG. 33 is a plan view of a sludge lance having a swing arm assembly attached to its distal end and a pointer assembly attached to its proximal end, illustrating the sludge lance in a configuration to align the nozzles of the sludge lance with tube gaps between tubes of the steam generator;

[0044] FIG. 34 is a plan view of the sludge lance of FIG. 33, illustrating the swing arm assembly in an alignment configuration for aligning the rails of the sludge lance parallel and centered with the tube lane;

[0045] FIG. 35 is a side elevation view of a sludge lance including a single rail intermediate the swing arm assembly and the pointer assembly, illustrating the swing arm assembly and a pointer of the pointer assembly oriented in position for assembly to the rail;

[0046] FIG. 36 is a front side view of the sludge lance of FIG. 35;

[0047] FIG. 37 is a back side view of the sludge lance of FIG. 35;

[0048] FIG. 38 is a plan view of the sludge lance of FIG. 35;

[0049] FIG. 39 is a cross section view of the sludge lance of FIG. 35 taken along line 39-39 in FIG. 38;

[0050] FIG. 40 is a front side view of the swing arm assembly of the sludge lance of FIG. 35, illustrating the swing arm in an orientation for insertion of the sludge lance into the tube lane;

[0051] FIG. 41 is back side view of the pointer assembly of the sludge lance of FIG. 35, illustrating the pointer of the pointer assembly in an orientation corresponding to sludge lance insertion into the tube lane;

[0052] FIG. 42 is front side view of the swing arm assembly of the sludge lance of FIG. 35, illustrating the swing arm in an orientation for aligning the nozzles of the sludge lance with the tube gaps;

[0053] FIG. 43 is back side view of the pointer assembly of the sludge lance of FIG. 35, illustrating the pointer of the pointer assembly in an orientation corresponding to aligning the nozzles of the sludge lance with the tube gaps;

[0054] FIG. 44 is front side view of the swing arm assembly of the sludge lance of FIG. 35, illustrating the swing arm in an orientation for aligning the sludge lance with the tube lane; and

[0055] FIG. 45 is back side view of the pointer assembly of the sludge lance of FIG. 35, illustrating the pointer of the pointer assembly in an orientation corresponding to aligning the sludge lance with the tube lane.

[0056] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate various aspects of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION

[0057] Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the aspects as described in the disclosure and illustrated in the accompanying drawings. Well-known operations, components, and elements have not been described in detail so as not to obscure the aspects described in the specification. The reader will understand that the aspects described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and illustrative. Variations and changes thereto may be made without departing from the scope of the claims. Furthermore, it is to be understood that such terms as forward, rearward, left, right, upwardly, downwardly, and the like are words of convenience and are not to be construed as limiting terms.

[0058] In the following description, reference characters designate like or corresponding parts throughout the several views of the drawings. Also in the following description, it is to be understood that such terms as forward, rearward, left, right, upwardly, downwardly, and the like are words of convenience and are not to be construed as limiting terms.

[0059] Before explaining various aspects of the sludge lance in detail, it should be noted that the illustrative examples are not limited in application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The illustrative examples may be implemented or incorporated in other aspects, variations, and modifications, and may be practiced or carried out in various ways. Further, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative examples for the convenience of the reader and are not for the purpose of limitation thereof. Also, it will be appreciated that one or more of the following-described aspects, expressions of aspects, and/or examples, can be combined with any one or more of the other following-described aspects, expressions of aspects, and/or examples.

[0060] In general, sludge lancing of steam generators with U-tubes is performed by directing fluid thru jets directed from the center of the steam generator towards the outside of the tube bundle where the contaminants are removed. The sludge lance is introduced through an opening typically referred to as a hand hole and then indexed along the tube lane to position the jet flow at the gaps between the tubes. Many of the steam generators have an approximate five inch to six inch diameter opening to access the tube lane which provides adequate access for sludge lance equipment as described in U.S. Pat. No. 8,238,510 entitled STEAM GENERATOR DUAL HEAD SLUDGE LANCE AND PROCESS LANCING SYSTEM which issued on Aug. 7, 2012. The disclosure of U.S. Pat. No. 8,238,510 is hereby incorporated by reference herein in its entirety. Further, other steam generators have openings in the range of two inches to four inches which limits the size and effectiveness of sludge lance tooling. Typically for the smaller openings only a single nozzle is utilized and requires opposing jets from the working jets to offset the reaction forces and minimize excessive deflection of the lance. Typically, the reaction force from a single jet is approximately 8-10 LBF and with multiple jets a significant load can be introduced at the exit of the lance. Additionally, the opposing balance jets double the high pressure water flow requirement and introduce excess fluid in the steam generator. The excess fluid must be removed and can decrease cleaning effectiveness if it remains on the tubesheet surface.

[0061] In general this disclosure relates to steam generators and more particularly to a sludge lance for removing sludge deposits from tube sheets of steam generators, in particular, nuclear steam generators using a dual nozzle sludge lance through an opening as small as two inches in diameter. In at least one aspect, when using a sludge lance having dual nozzles, the lancing time and pumping requirements may be reduced by approximately 50% as compared to with a single nozzle with balance jets. In at least one aspect, the dual nozzle sludge lance can be supported in a cantilever configuration in order for the jet reaction vertical force to, at least partially, oppose the gravitational force acting on the lance. Further, the horizontal forces (i.e., lateral forces) oppose each other and essentially cancel which allows the lance to be properly positioned relative to the tube gaps. Further, in various aspects, a rotational drive configuration for the dual nozzle sweep provides a compact envelope while maintaining accuracy. Further, in various aspects during assembly/disassembly of the lance extensions (i.e., rails) the rotational drive shafts passively lock and unlock to maintain alignment. In various aspects, means are provided to accurately align the sludge lance parallel and in line with the tube gaps between the tubes of the steam generator.

[0062] Due to lack of present capability, the sludge lance of this disclosure may be used in Embalse, Argentina, a model CANDU 600 steam generator. Upon review of other steam generators it may directly to apply to others, particularly in France. In at least one aspect, the sludge lance of this disclosure incorporates Westinghouse Stellar lancing technology.

[0063] FIG. 1 illustrates a partial cross sectional view of a steam generator 100 comprising a plurality of tubes 110 arranged in a tube bundle 120 and held together by a plurality of plates (not shown). In at least one aspect, the plurality of plates comprise a plurality of tube support plates and at least one tube sheet (not shown). The tube sheet both holds the tubes in place and is the pressure boundary between the primary (pressurized water) and secondary (lower pressure water). In at least one aspect, the tubesheet is at the lowest elevation in secondary side of the steam generator 100 where most of the sludge is typically deposited during operation. In any event, the cross-section of FIG. 1 is taken just above the tubesheet. In at least one aspect, the plurality of tube support plates comprise a plurality of holes which hold the plurality of tubes 110 in position within the steam generator 100. In various aspects, there may be one or more than one tube support plate vertically positioned relative to the tubes 110 to hold the tubes 110 in position.

[0064] Further to the above, the steam generator 100 further comprises an elongate central tube lane 150 defined intermediate the plurality of tubes 110. Further, an annulus 155 is defined intermediate the tubes 110 and an inner wall 190 of the steam generator 100. During operation of the plant, water outside of tubes 110 is converted to steam leaving residue between the tubes 110, on the tubes 110, on the tubesheet, and/or on a tube support plate structure (not shown). Typical access for sludge lancing is through the 0 hand hole 140 or a 180 hand hole 160 shown in FIG. 1. Typically, the lance is indexed at the tube gaps along the tube lane 150. When traversing to each index position, the lance will direct high pressure fluid towards the tubesheet. At each tube gap, the lance will then sweep the directed fluid beginning at the tube lane 150 and then outward toward annulus 155. Typically, additional fluid is injected along the annulus 155 to move the contaminants towards a 90 hand hole 170 or a 270 hand hole 180 where the fluid is removed from the steam generator 100 with suction.

[0065] FIGS. 2 and 3 illustrate a sludge lance system 1000 comprising a sludge lance 1100, a mount 7, and an index drive unit 6. The sludge lance 1100 comprises a head assembly 1, a plurality of rails extending proximally from the head assembly 1, an oscillator manifold 10 extending proximally from the plurality of rails 2, and an oscillator assembly 5 extending from the oscillator manifold 10. FIGS. 2 and 3 illustrate the sludge lance 1100 passing through the zero degree hand hole 140 of the steam generator 100. It should be understood that the sludge lance system 1000 can also be positioned relative to the steam generator 100 such that the sludge lance 1100 passes through the 180 degree hand hole 160 shown in FIG. 1. In FIGS. 2 and 3, three rails 2 are positioned intermediate the oscillator manifold 10 and the head assembly 1. In various aspects, the head assembly 1 is attached to one or more than one rail assembly 2 which rigidly position the head assembly 1 relative to the steam generator 100. In any event, the head assembly 1 comprises a plurality of nozzles 15a, 15b attached thereto for ejecting lancing fluid.

[0066] Further to the above, the index drive unit 6 constrains the longitudinal rails 2 both vertically and horizontally and advances and retracts the sludge lance 1100 relative to the steam generator 100. Further, the oscillator assembly 5 provides the rotational drive for the nozzles 15a, 15b of the head assembly 1. In at least one aspect, the drive unit 6 comprises a plurality of first rollers 6a engaged with a top face 2a of the rail 2 and a plurality of second rollers 6b engaged with a bottom face 2b of the rail 2 (see FIG. 3). The plurality of first rollers 6a and the plurality of second rollers 6b are configured to advance the head assembly 1 along the elongate tube lane 150 by advancing one or more rails 2 along a longitudinal axis LA (see FIG. 2).

[0067] Further to the above, the rail assemblies 2 transport the lancing fluid to the head assembly 1. Specifically, lancing fluid is introduced into a rotary quick connect 4 and passes through the oscillator manifold 10 and into one of the rail assemblies 2. The rotary quick connect 4 permits free rotary motion for the connected hose about axis AA shown in FIG. 2. Further, a pointer 8 on the drive unit 6 is adjusted during the alignment process to register with alignment marks 9 on each of the rails 2.

[0068] Further to the above, the sludge lance 1100 is attached to the steam generator by way of a mount 7 that provides a ridged interface between the steam generator 100 and the index drive unit 6. The mount 7 is fixed to the outside of the steam generator 100 and supports the index drive unit 6. Further, the mount 7 provides means to adjust the position of the lance 1100 relative to the steam generator 100, the hand hole opening 140, and the steam generator tube bundle 120. In various aspects, the oscillator 5, index drive 6, and mount 7 may be of the types described in U.S. Pat. No. 9,920,925 entitled STEAM GENERATOR SLUDGE LANCE APPARATUS which issued on Mar. 20, 2018. The disclosures of U.S. Pat. No. 9,920,925 is hereby incorporated by reference herein in its entirety. In at least one aspect, the sludge lance 1100 is a cantilever sludge lance, i.e., supported by the mount 7 and index drive unit 6 at its proximal end and unsupported at its distal end.

[0069] Referring primarily to FIGS. 4-6, the head assembly 1 comprises a body portion 1a comprising a housing 13 and a nozzle guide 14 extending distally from the housing 13. The head assembly 1 further comprises a first nozzle body 12a and a second nozzle body 12b. The first nozzle body 12a comprises a plurality of first nozzles 15a and the second nozzle body 12b comprises a plurality of second nozzles 15b. The first nozzles 15a are configured to emit lancing fluid along first flow paths FFP and the second nozzles 15b are configured to emit lancing fluid along second flow paths SFP (see FIG. 7).

[0070] Further to the above, a central vertical plane CVP is defined by the body portion 1a as shown in FIGS. 5 and 7. The first nozzle body 12a is positioned on a first lateral side 14a of the central vertical plane CVP and the second nozzle body 12b is positioned on a second lateral side 14b of the central vertical plane CVP. Further, the first nozzle body 12a is rotatable relative to the body portion 1a about a first longitudinal axis FLA and the second nozzle body 12b is rotatable relative to the body portion 1a about a second longitudinal axis SLA (see FIG. 5). Further, FIG. 4 illustrates the nozzles 15a, 15b pointing in a downward direction DD and FIG. 7 illustrates the nozzles 15a, 15b pointing horizontally outward from the central vertical plane CVP (i.e., the nozzles 15a, 15b are a mirror image about the central vertical plane CVP). In other words, the nozzles 15a, 15b have been rotated 90 upward from the orientation in FIG. 4 to the orientation in FIG. 7. Similarly, the nozzles 15a, 15b are point in the downward direction in FIG. 3 and the nozzles 15a, 15b are pointing horizontally outward in FIG. 2.

[0071] In use, pressurized fluid is injected into a split port 11 of housing 13 which splits the flow into two and feeds the fluid into the first nozzle body 12a and the second nozzle body 12b. A cross-section of the split port 11 is shown in FIG. 8 and the split port 11 is shown in hidden lines in FIG. 7. Further, housing 13 supports the nozzle guide 14 and associated bearings to rotatably support the first and second nozzle bodies 12a, 12b relative to the body portion 1a. The nozzle guide 14 is positioned relative to the housing 13 by way of dowel pins 32 (FIG. 9) and is attached to the housing 13 by screws 31 (FIG. 10). Further, referring primarily to FIG. 5, the nozzle bodies 12a, 12b comprise flat lateral sides so as not to encroach on the width of the head assembly 1 when passing through the hand hole 140.

[0072] Referring primarily to FIGS. 7-9, the pressurized fluid for each nozzle body 12a, 12b enters from split port 11 and is directed downward into two annuli 16 defined on either side of the central vertical plane CVP between the nozzle bodies 12a, 12b and the housing 13. A seal plug 33 (see FIG. 9) is installed after fabrication of vertical flow ports 33a to maintain the fluid pressure boundary. From annuli 16, the fluid enters and travels through an offset port 17 defined in each of the nozzle bodies 12a, 12b. Fluid then subsequently flows from the offset ports 17 into the nozzles 15a, 15b. In at least one aspect, the nozzles 15a, 15b may be of the types described in U.S. Pat. No. 8,646,416 entitled MINIATURE SLUDGE LANCE APPARATUS which issued on Feb. 11, 2014. The disclosure of U.S. Pat. No. 8,646,416 is hereby incorporated by reference herein in its entirety. The nozzles 15a, 15b provide highly collimated fluid flow for sludge lance 1100. Further, the offset ports 17 are offset from the nozzle rotational axes (i.e., the first longitudinal axis FLA and the second longitudinal axis SLA). This provides clearance for the nozzles 15a, 15b to sweep (i.e., rotate) while maintaining a small space envelope. The head assembly 1 further comprises leak limiting high pressure seals 19 (see FIGS. 7 and 9) to minimize rotational friction. Further, excess seal leakage passes through rear port 20 (FIG. 9) and front port 21 (FIG. 7).

[0073] One potential issue with reducing the rotational space envelope of the nozzle bodies 12a, 12b is the need for low friction bearings to permit the desire rotation of the nozzle bodies 12a, 12b relative to the body portion 1a. Referring primarily to FIGS. 7 and 9, the distal end of each of the nozzle bodies 12a, 12b is supported by a ball bearing 22 with sufficient load capability. However, a commercially available ball bearing for the rear of the nozzle bodies 12a, 12b will likely have an inside diameter greater than the outside diameter of the high pressure seal 19. In other words, the outside diameter of a commercial ball bearing and supporting structure of approximately 1 inch or greater will not permit the space envelope to pass through a 2 inch steam generator opening. One potential solution to this problem is to utilize a split cage needle roller bearing 23 to support each of the proximal ends of the nozzle bodies 12a, 12b as shown in FIGS. 7 and 9. The split cage needle roller bearing 23 provides the radial support for the nozzle bodies 12a, 12b with a small radial envelope. Typically for ball bearings, the material of the balls and mating races must be of sufficient hardness (typically around Rc 60) to preclude failure. However, use of the roller bearing 23 has significantly lower contact stress such that no hardened races are required thus reducing the radial envelope of the bearing as the rollers directly contact the nozzle body 12a, 12b and surrounding housing 13.

[0074] Further to the above, FIGS. 11-13 illustrate the split cage needle roller bearing 23. The bearing 23 comprises a plurality of rollers 26 and is defined by two cages 24 that are held together by four pins 25. FIG. 11 shows only one of the cages 24 of the bearing 23 without the rollers 26 for clarity. The cages 24 of the bearing 23 provide separation of rollers 26 for reduced friction. The split cage design of the bearing 23 permits installation about a smaller outside diameter shaft as compared to a commercial ball bearing. In at least one aspect, the bearing 23 is located at the intersection of offset ports 17. Further, low pressure seals 27 (FIGS. 7 and 9) protect the split cage needle roller bearing 23 by retaining grease and providing a barrier for exterior contaminants.

[0075] Referring primarily to FIG. 9, the head assembly 1 further comprises a seal ring assembly 28 containing two low pressure seals 29 which direct any leakage from the rear high pressure seal through the rear port 20. Each seal ring assembly 28 also comprises a bushing 30 which axially restrains the nozzle bodies 12a, 12b in conjunction with a ball bearing 22 (see FIG. 9). Bushing 30 also minimizes radial deflection at the rear of the nozzle bodies 12a, 12b.

[0076] As discussed above, in various aspects, the head assembly 1 is attached to a plurality of rail assemblies 2 as shown in FIGS. 2 and 3. FIGS. 14-23 illustrate one of the rail assemblies 2. In various aspects, multiple rails 2 can be attached together as described in U.S. Pat. No. 8,646,416. Further, in various aspects, one rail 2 is attached to another rail 2 by screws 34 that extend distally from the rail 2. The screws 34 are engaged with threaded holes 34a in the proximal end of another rail 2. Further, the screws 34 are retained by screw retainers 36 (see FIGS. 14 and 19). A pair of spring pins 37 secure each screw retainer 36 (see FIG. 20). Each rail 2 is accurately aligned to another rail 2 by way of dowel pins 35 which are received in holes 35a in the proximal end of another rail 2. Pressurized fluid flows through a port 40 defined in each rail 2. The flow port 40 is sealed within each rail 2 with an O-ring 39 (see FIG. 18). Referring primarily to FIG. 28, one of the rails 2 is also attachable to the head assembly 1 by way of the screws 34. FIG. 28 illustrates a single rail 2 attached to the head assembly 1 intermediate the oscillator manifold 10 and the oscillator assembly 5. However, as discussed above, multiple rails 2 may be attached together and then attached to the head assembly 1, the oscillator manifold 10, and the oscillator assembly 5.

[0077] Further to the above, in at least one aspect, the pair of rail attachment screws 34 and the rail 2 cross sectional geometry permit lance configurations to extend more than 10 feet which permits installation and lancing from a single hand hole in instances where there may be space limitations on the opposite hand hole. U.S. Pat. No. 8,646,416 further describes the alignment marks 9, recesses 38 (see FIG. 17) used to positively index a lance assembly at the tube gaps, the tapered keyed coupling of each drive shaft 41a, 41b, and the drive shaft bearings 42 and 43.

[0078] Further to the above, each rail 2 comprises a pair of drive shafts 41a and 41b housed therein (see FIGS. 15, 16, and 20). When more than one rail 2 is attached, the drive shafts 41a, 41b within each rail are operably engaged. Further, when one or more than one rail 2 is attached to the head assembly 1, the drive shafts 41a, 41b are operably engaged with the nozzle bodies 12a, 12b. For example, FIG. 28 illustrates one rail 2 attached to the head assembly 1. As shown in FIG. 30 the drive shaft 41b is operably engaged with the rotatable second nozzle body 12b. Similarly, the drive shaft 41a is operably engaged with the rotatable first nozzle body 12a. The drive shafts 41a, 41b within each rail 2 are utilized to rotate the nozzle bodies 12a, 12b simultaneously and in opposite directions, as described in greater detail herein.

[0079] Further to the above, in at least one aspect, the above described dual drive shaft configuration solves a potential size problem that exists when trying to place multiple gears in the head assembly 1. In other words, the dual drive shaft arrangements described herein permit placing the rotational drive for the nozzle bodies 12a, 12b outside of the steam generator 100 where more space is available. In addition, with two drive shafts, less than 50% of the torque is required for each drive shaft which reduces torsional deflection and rotational position errors of the nozzle bodies.

[0080] Further to the above, when coupling one or more rails 2 together, a male flat 52 (see FIG. 20) at the distal end of each drive shaft 41a, 41b of one of the rails 2 must rotatably align with a corresponding female flat 53 at the proximal end of the drive shafts 41a, 41b of another one of the rails 2. Further, when coupling the distal end of one or more than one rail 2 to the head assembly 1, the male flat 52 on the distal end of each of the drive shafts 41a, 41b must rotatably align with a corresponding female flat 53b of a coupler 53a attached to each of the nozzle bodies 12a, 12b (see FIGS. 7 and 30). Further, when coupling one of the rails 2 to the oscillator manifold 10, the female flats 53 on the proximal ends of each of the drive shafts 41a, 41b must rotatably align with corresponding male flats 59a on a first shaft 59 and male flat 63a on a second shaft 63 housed within the oscillator manifold 10 (see FIG. 31). The connection between the drive shafts 41a, 41b of the rail 2 to the oscillator manifold 10 is described in greater detail below.

[0081] Referring primarily to FIG. 20, each rail 2 comprises bearings 42, 43 positioned intermediate the drive shafts 41a, 41b which rotatable support the drive shafts 41a, 41b relative to the rail 2. Each rail drive shaft 41a, 41b is free to rotate on bearings 42, 43. Because each rail drive shaft 41a, 41b is free to rotate on bearings 42 and 43, the rotational orientation of the flats 52, 53 of the drive shafts 41a, 41b must be visually confirmed and manually adjusted if required. Due to the work environment, proper rotational alignment of the drive shafts 41a, 41b may be difficult. One solution to this problem is a lock mechanism 200 (see FIG. 20) which locks the orientation of the drive shafts 41a, 41b relative to the rail 2 prior to attaching the rail 2 and unlocks the drive shafts 41a, 41b when the rails 2 are joined together and/or when the rails 2 are joined to the oscillator manifold 10. In other words, the drive shafts 41a, 41b are rotationally lockable relative to the rail 2 prior to attaching the rail 2 to the head assembly 1 and/or to the oscillator manifold 10 during assembly of the sludge lance 1100. Upon coupling of the rail 2, the lock mechanism 200 freely releases the rail drive shafts 41a, 41b permitting them to rotate. In at least one aspect, freely releasing the drive shafts 41a, 41b upon attachment reduces friction induced torsional deflection of the drive shafts 41a, 41b and decreases the torque requirement for nozzle body 12a, 12b rotation. The lock mechanism 200 is discussed in greater detail below.

[0082] Referring primarily to FIGS. 20-25, each rail 2 comprises two locking mechanisms 200, i.e., one lock mechanism 200 corresponding to each of the drive shafts 41a, 41b respectively. Each lock mechanism 200 comprises a lock pin 44, a set screw 51, a spring plunger 47, a compression spring 48, a lock cam 45, and bushings 46. Further, FIGS. 20 and 21 illustrate the rail 2 prior to attachment with the drive shafts 41a rotationally locked relative to the rail 2. To lock the orientation of the drive shafts 41a relative to the rail 2, the compression spring 48 acts on the spring plunger 47 which forces the lock cam 45 proximally. Referring primarily to FIGS. 24 and 25, the lock pin 44 comprises angled grooves 44a defined therein on either side of the lock pin 44. Further, the lock cam 45 comprises lock cam arms 45a extending distally. The lock cam arms 45a of the lock cam 45 are received in the angled grooves 44a of the lock pin 44. As such, prior to attaching the rail 2, the lock cam 45 is biased proximally by the spring plunger 47 which biases the lock pin 44 in the downward direction DD (see FIG. 20). Further, when the lock pin 44 is biased downward, the lock pin 44 engages a flat 50 on the drive shaft 41a to rotatably secure the drive shaft 41a relative to the rail 2. Similarly, the other drive shaft 41b can be rotationally secured to the rail 2 by way of another lock mechanism 200 having another lock pin 44 that engages another flat 50 on the drive shaft 41b (see FIG. 21).

[0083] FIGS. 22 and 23 illustrate the configuration when the drive shafts 41a, 41b are released and free to rotate. Specifically, to unlock the locking mechanism 200 the lock cam 45 is translated distally (i.e., toward the lock pin 44 as shown in FIG. 22). As the lock cam 45 moves toward the lock pin 44, the lock cam arms 45a of the lock cam 45 will drive the lock pin 44 in the upward direction UD and disengage the lock pin 44 from the flat 50 of the drive shaft 41a. Further, the other lock pin 44 of the other lock mechanism 200 is disengaged from the drive shaft 41b in the same manner.

[0084] Further to the above, when two rails 2 are attached together, the lock cams 45 at the interface between the two rails 2 will move toward the lock pins 44 to disengage the lock pins 44 from the drive shafts 41a, 41b of the distal most rail. However, the drive shafts 41a, 41b of the proximal most rail will remained engaged by the lock pins 44 owing to the lock cams 45 of the proximal most rail remaining biased away from the lock pins 44 after the rails are attached together. As discussed above, when two rails are attached together, the drive shafts 41a, 41b of both rails are engaged with each other. As such, when the lock mechanism 200 of the proximal most rail remains engaged with its respective drive shafts 41a, 41bthe drive shafts 41a, 41b of both rails will remain rotationally locked. The drive shafts 41a, 41b of the two rails are rotationally released when the proximal most rail is attached to the oscillator manifold 10. Specifically, when the proximal most rail is attached to the oscillator manifold 10, the lock cams 45 of the proximal most rail will move toward the lock pins 44 to disengage the lock pins 44 from the drive shafts 41a, 41b of the proximal most rail. As such, all of the drive shafts 41a, 41b of all of the rails of the entire assembly are now released and free to rotate. It should be understood that the design of the rails 2 and lock mechanisms 200 permits two or more rails to be attached to one another with their drive shafts 41a, 41b rotationally locked until the proximal most rail is attached to the oscillator manifold 10.

[0085] Further to the above, in at least one aspect, only one rail 2 is attached to the head assembly 1. In such an instance, the drive shafts 41a, 41b of the rail 2 are released when the rail 2 is attached to the oscillator manifold 10 as shown in FIG. 30. In any event, it should be appreciated that when all components of the lock mechanisms 200 are installed to the rail 2, that the entire lock mechanism 200 is constrained within the rail 2 to prevent loose parts.

[0086] Further to the above, the set screws 51 preclude contaminants from entering around the lock pins 44. In at least one aspect, due to the high stress on the lock cam arms 45a that engage the lock pin 44, the lock cam 45 and lock cam arms 45a may comprise a high strength stainless steel, such as 17-4 PH, for example. To reduce sliding friction of the lock cam 45, the pair of split bushings 46 are concentrically engaged with the lock cam 45. In at least one aspect, the lock pin 44, the bushings 46, and the spring plunger 47 are fabricated from a bearing grade polymer such as Delrin, Delrin af, or Torlon. Further, threaded holes 54 are provided on the lock pin 44, the lock cam 45, and the spring plunger 47 to assist in assembly and disassembly of the lock mechanism 200.

[0087] FIGS. 26-28 illustrate the head assembly 1, the rail 2, the oscillator assembly 5, and the oscillator manifold 10. Only one rail 2 is shown for simplicity. Referring primarily to FIG. 26, pressurized fluid from the swivel connector 4 passes through a manifold port 55 defined in the oscillator manifold 10 and is coupled to the rail port 40. As discussed above, the fluid passes through the rail port 40 and into the split port 11 in the head assembly 1 where it is distributed into the offset ports 17 of the nozzle bodies 12a, 12b and into the nozzles 15a, 15b. Further, rotation for the nozzle bodies 12a, 12b is achieved through a miter gear set in oscillator assembly 5. In various aspects, the oscillator assembly 5 may be similar to those described in U.S. Pat. No. 9,920,925.

[0088] As discussed above, rotation for the drive shafts 41a, 41b of the rail 2 is performed simultaneously and in opposite rotational directions. Further, an axial load and axial translation is applied to each drive shaft 41a, 41b to maintain the drive couplings in intimate contact for elimination of backlash at the joints. FIGS. 31 and 32 illustrate the rail 2 attached to the oscillator manifold 10 which is attached to the oscillator assembly 5. In at least one aspect, the oscillator manifold 10 is a transmission that converts a single rotational input from the oscillator assembly 5 into to two rotational outputs to drive the drive shafts 41a, 41b of the rail 2, as discussed in greater detail below.

[0089] Oscillator assembly 5 provides a single rotational input to the oscillator manifold 10 by way of a rotary shaft 58 (see FIG. 31). The rotary shaft 58 is slidably coupled to the first shaft 59 of the oscillator manifold 10 by way of a square 60 or spline. The first shaft 59 is also slidably and rotationally coupled to a first gear 61 of the oscillator manifold 10 by way of a square or spline which rotates a second gear 62 in the opposite direction. The second gear 62, having a similar square or spline interface, provides rotation to the second shaft 63. Both the first gear 61 and the second gear 62 are supported by a set of ball bearings 64.

[0090] In use, when the rotary output shaft 58 is rotated in the counter clock-wise direction CCW shown in FIGS. 31 and 32, the first shaft 59 will rotate in direction CCW (i.e., the same direction) and the second clockwise in shaft 63 will rotate direction CW (i.e., the opposite direction). As such, the first rotary drive shaft 41a of the rail 2 will rotate in direction CW resulting in rotation of the first nozzle body 12a in the first direction FD (see FIG. 5). Further, the second rotary drive shaft 41b of the rail 2 will rotate in direction CCW resulting in the rotation of the second nozzle body 12b in the second direction SD opposite the first direction FD (see FIG. 5). It should be understood that rotation of the rotary output shaft 58 in the clockwise direction CW will result in the first nozzle body 12a rotating in the second direction SD and the second nozzle body 12b rotating in the first direction FD opposite the second direction SD. As such, the first nozzle body 12a and the second nozzle body 12b rotate in opposite directions in response to a given rotation of the rotary output shaft 58 of the oscillator assembly 5. In various aspects, rotation of the nozzle bodies 12a, 12b is synchronized to maintain the first flow paths FFP and the second flow paths SFP mirrored about the central vertical plane CVP. In at least one aspect, orienting the first flow paths FFP and the second flow paths SFP in this manner balances out the forces acting on the head assembly 1 when fluid is emitted through the nozzles 15a, 15b.

[0091] In at least one aspect, the rotational travel of the oscillator assembly 5 is limited to +90 degrees. Referring to FIG. 29, a dowel pin 56 of the oscillator assembly 5 is illustrated. The dowel pin 56 moves when the rotary output shaft 58 of the oscillator assembly 5 is rotated. When the dowel pin 56 reaches a travel limit at either position 57 shown in FIG. 29, high torque and rotation stoppage is sensed by the control system in order to reset the home position. Owing to the relationship between the rotary output shaft 58 of the oscillator assembly 5 and the nozzle bodies 12a, 12b described above, the rotational travel of the nozzle bodies 12a, 12b can also be limited to +90 degrees. In other words, in at least one aspect, the nozzle bodies 12a, 12b are only rotatable between the horizontal orientation (FIG. 7) and the downward orientation (FIG. 4).

[0092] In at least one aspect, to provide flexibility during assembly in the field, the oscillator assembly 5 can be mounted to the oscillator manifold 10 rotated 180 degrees from the configuration in FIG. 31. In such a configuration, the output shaft 58 of the oscillator assembly 5 will be engaged with the second shaft 63. To achieve this flexibility, the output shaft 58 is recessed distance A from surface 65 permitting engagement with either the first shaft 59 or the second shaft 63 of the oscillator manifold 10. Additionally, the end of each shaft 59, 63 is recessed a distance B from surface 65 permitting clearance to mount the oscillator 5 in either orientation.

[0093] Further to the above, the configuration for maintaining the axial load and translation for the drive shaft 41a is shown in FIG. 30 and described herein. It should be understood that the same configuration exists to maintain the axial load and translation of the second drive shaft 41b of the rail 2 and the second shaft 63 of the oscillator manifold 10. As previously described, rotation of the output shaft 58 is slidably coupled to the first shaft 59 of the oscillator manifold 10 by way of the square 60 or spline. A square or spline coupling is also used to rotationally couple the first shaft 59 to the first gear 61. The front of each shaft 59, 63 of the oscillator manifold 10 is concentrically restrained toward the distal end of the oscillator manifold 10 with a split bushing 66. The proximal end of the shafts 59, 63 are concentrically restrained with the first gear 61 and the second gear 62, respectively. The shafts 59, 63 can translate +X (see FIG. 30) to compensate for manufacturing tolerances of the rails 2, manufacturing tolerances of the shafts 41a, 41b, 59, 63, and the interfaces between the shafts 41a, 41b, 59, 63 (e.g., the couplings).

[0094] Further to the above, in order to eliminate, or at least reduce, backlash at the tapered coupling of each shaft 41a, 41b, 59, 63, an axial force is applied to all of the drive shafts. Specifically, a compression spring 67 biases a spacer 68 proximally and biases the split bushing 66 distally. The Spacer 68 is axially restrained by the gear 61 and the ball bearing 64. In at least one aspect, the ball bearing 64 transfers the load to the oscillator manifold 10 with minimal rotational friction. The net resultant compression spring force is in the distal direction against the split bushing 66 which imparts a load in the distal direction on the first shaft 59 of the oscillator manifold 10 and the first drive shaft 41a of the rail 2 until restrained by the ball bearing 22 at the distal end of the head assembly 1. A similar configuration is utilized to eliminate, or at least reduce, backlash for the second shaft 63 of the oscillator manifold 10 and the second drive shaft 41b of the rail 2.

[0095] FIG. 33 is a plan view of a sludge lance 1100 that is similar to the sludge lance 1100 except for the difference discussed herein. Specifically, the sludge lance 1100 has been fitted with a swing arm assembly 70 at its distal end (i.e., instead of the head assembly 1) and a pointer assembly 71 at its proximal end (i.e., instead of the oscillator manifold 10 and oscillator assembly 5). The sludge lance 1100 of FIG. 33 is configured for alignment of the nozzle jets to tube gaps 72. For effective cleaning, the nozzle jets must accurately index to each tube gap and the lance 1100 must index parallel to the tube lane 150. For alignment, the swing arm assembly 70 and the pointer assembly 71 are attached to one or more rail assemblies 2. In at least one aspect, the swing arm assembly 70 and the pointer assembly 71 are similar to those disclosed in U.S. Pat. No. 9,920,925. In various aspects, the swing arm assembly 70 and the pointer assembly 71 can be coupled to either of the drive shafts 41a, 41b of the rails 2 depending on the specific location of the tubes 110 relative to the hand hole 140. FIG. 39 illustrates a swing arm 73 of the swing arm assembly 70 and a pointer 74 of the pointer assembly 71 operably attached to the drive shaft 41a of the rail 2. In use, when the swing arm 73 of the swing arm assembly 70 is positioned perpendicular to the centerline of the tubes 110, the rails 2 are moved distally until the front edge of the swing arm 73 contacts the outside diameter of one of the tubes 110. At this time, the pointer 8 on the drive unit 6 is adjusted to register with the alignment marks 9 (see FIG. 3) on the rails 2.

[0096] FIG. 34 is a plan view of the sludge lance 1100 configured to alignment the rails 2 parallel and centered to the tube lane 150. After the pointer 8 on the drive unit 6 is adjusted to register with the alignment marks 9 on the rails 2, movement to every other alignment mark 9 places the swing arm 73 at a given tube location. The swing arm 73 is then rotated to contact the tube outside diameter which provides an angular displacement of the swing arm 73 at the pointer assembly 71. The rail assembly 2 is further indexed to other tube locations where the angular displacement of the swing arm 73 is noted. If required, angular adjustment of the drive unit 6 is performed to position the rail assemblies 2 parallel and centered to the tube lane 150. When parallel and centered, the pointer 8 readings will have little variation and be close to zero. After the rail assemblies 2 are parallel and centered to the tube lane 150, slight adjustment to the index location may be required.

[0097] FIGS. 35-38 illustrates a single rail 2 configured for alignment with the swing arm 73 and a pointer 74 of the pointer assembly 71 oriented in position for assembly to the rail 2. As shown in FIGS. 39 and 40, a plurality of V-shaped grooves 75 in the swing arm assembly 70 orient the swing arm 73 in position by engaging a spring loaded ball 79 located on the swing arm 73. Specifically, a vertical groove 75a holds the swing arm 73 in an assembly configuration illustrated in FIGS. 35-37. Further, the angled groove 75b holds the swing arm 73 in an insertion configuration illustrated in FIGS. 40 and 41. When the swing arm 73 is in the insertion configuration, the swing arm 73 is within the constraints of the rail outline to facilitate insertion of the rail 2 through the drive unit 6. Further, a horizontal groove 75c holds the arm in an alignment configuration as shown in FIGS. 42 and 43. During alignment of the swing arm 73 to the tube gaps, the swing arm 73 is held horizontally using the groove 75c. Further, there is no engagement between the swing arm 73 and any of the grooves 75 when the swing arm 73 is used to measure the distance from the rail 2 to the outside diameter of a given tube 110 as shown in FIGS. 44 and 45.

[0098] Various aspects of the present disclosure include, but are not limited to, the aspects listed in the following numbered clauses.

[0099] Clause 1A sludge lance system for cleaning a tube bundle of a steam generator. The steam generator comprises at least one hand hole opening which provides access to an elongate central tube lane within the tube bundle. The elongate central tube lane defines a longitudinal axis. The sludge lance system comprises a mount positioned outside the steam generator, an index drive supported by the mount, and a sludge lance movable along the longitudinal axis of the elongate central tube lane by the index drive. The sludge lance comprises a proximal end, a distal end, a longitudinal rail, a manifold extending proximally from the longitudinal rail, an oscillator assembly extending from the manifold, and a distal head extending distally from the longitudinal rail. The oscillator assembly comprises a rotary output shaft. The distal head comprises a body portion, a first nozzle body, and a second nozzle body. The first nozzle body is positioned on a first lateral side of the body portion. The first nozzle body comprises a first plurality of nozzles. The first nozzle body is rotatable relative to the body portion about a first longitudinal axis in a first direction in response to a rotation of the rotary output shaft of the oscillator assembly. The second nozzle body is positioned on a second lateral side of the body portion opposite the first lateral side. The second nozzle body comprise a second plurality of nozzles. The second nozzle body is rotatable relative to the body portion about a second longitudinal axis in a second direction in response to the rotation of the rotary output shaft of the oscillator assembly. The second direction is opposite the first direction.

[0100] Clause 2The sludge lance system of Clause 1, wherein each of the plurality of first nozzles are to emit fluid along a first flow path, wherein each of the plurality of second nozzles are to emit fluid along a second flow path, and wherein the first flow paths and the second flow paths are mirrored about a central vertical plane of the distal head.

[0101] Clause 3The sludge lance system of Clause 2, wherein rotation of the first nozzle body and the second nozzle body is synchronized to maintain the first flow paths and the second flow paths mirrored about the central vertical plane.

[0102] Clause 4The sludge lance system of Clauses 1, 2, or 3, wherein the sludge lance is solely supported by the mount and the index drive.

[0103] Clause 5The sludge lance system of Clauses 1, 2, 3, or 4, wherein the sludge lance is a cantilever sludge lance supported by the mount and the index drive.

[0104] Clause 6. The sludge lance system of Clauses 1, 2, 3, 4, or 5, wherein the sludge lance is unsupported at the distal end.

[0105] Clause 7The sludge lance system of Clauses 1, 2, 3, 4, 5, or 6, wherein the index drive is operably engaged with the rail and prevents horizontal and vertical movement of the rail, and wherein the index drive is to advance the distal head along the elongate central tube lane by advancing the rail along the longitudinal axis.

[0106] Clause 8The sludge lance system of Clauses 1, 2, 3, 4, 5, 6, or 7, wherein the index drive comprises a plurality of first rollers engaged with a top face of the rail and a plurality of second rollers engaged with a bottom face of the rail, and wherein the plurality of first rollers and the plurality of second rollers are to advance the distal head along the elongate central tube lane by advancing the rail along the longitudinal axis.

[0107] Clause 9The sludge lance system of Clauses 1, 2, 3, 4, 5, 6, 7, or 8, wherein the rail comprises a first drive shaft operably engaged with the first nozzle body and a second drive shaft operably engaged with the second nozzle body, and wherein the first drive shaft and the second drive shaft are operably engaged with the rotary output shaft of the oscillator assembly.

[0108] Clause 10The sludge lance system of Clause 9, wherein the manifold comprises a transmission to convert the rotation of the rotary output shaft of the oscillator assembly to rotation of the first drive shaft and the second drive shaft in opposite directions.

[0109] Clause 11The sludge lance system of Clause 9 or 10, wherein the first drive shaft and the second drive shaft of the rail are rotationally lockable relative to the rail prior to attaching the rail to the manifold during assembly of the sludge lance.

[0110] Clause 12The sludge lance system of Clause 11, wherein the first drive shaft and the second drive shaft are rotationally unlocked upon attachment to the manifold during assembly of the sludge lance.

[0111] Clause 13A sludge lance system for cleaning a tube bundle of a steam generator. The steam generator comprises at least one hand hole opening which provides access to an elongate central tube lane within the tube bundle. The elongate central tube lane defines a longitudinal axis. The sludge lance system comprises a mount positioned outside the steam generator, an index drive supported by the mount, and a sludge lance movable along the longitudinal axis of the elongate central tube lane by the index drive. The sludge lance comprises a proximal end, a distal end, a longitudinal rail and a distal head extending distally from the longitudinal rail. The distal head comprises a body portion, a first nozzle body, and a second nozzle body. The body portion defining a central vertical plane. The first nozzle body is positioned on a first lateral side of the central vertical plane. The first nozzle body comprises a first plurality of nozzles. The first nozzle body is rotatable relative to the body portion about a first longitudinal axis. The second nozzle body is positioned on a second lateral side of the central vertical plane opposite the first lateral side. The second nozzle body comprise a second plurality of nozzles. The second nozzle body is rotatable relative to the body portion about a second longitudinal axis. Each of the plurality of first nozzles are to emit fluid along a first flow path. Each of the plurality of second nozzles are to emit fluid along a second flow path. The first flow paths and the second flow paths are mirrored about the central vertical plane.

[0112] Clause 14The sludge lance system of Clause 13, wherein rotation of the first nozzle body and the second nozzle body is synchronized to maintain the first flow paths and the second flow paths mirrored about the central vertical plane.

[0113] Clause 15The sludge lance system of Clause 13 or 14, wherein the sludge lance is solely supported by the mount and the index drive.

[0114] Clause 16The sludge lance system of Clauses 13, 14, or 15, wherein the sludge lance is unsupported at the distal end.

[0115] Clause 17The sludge lance system of Clauses 13, 14, 15, or 16, wherein the index drive is operably engaged with the rail and prevents horizontal and vertical movement of the rail, and wherein the index drive is to advance the distal head along the elongate central tube lane by advancing the rail along the longitudinal axis.

[0116] Clause 18The sludge lance system of Clause 13, 14, 15, 16, or 17, wherein the sludge lance further comprises an oscillator assembly, wherein the rail comprises a first drive shaft operably engaged with the first nozzle body and a second drive shaft operably engaged with the second nozzle body, and wherein the first drive shaft and the second drive shaft are operably engaged with a rotary output shaft of the oscillator assembly.

[0117] Clause 19The sludge lance system of Clause 18, wherein the first nozzle body and the second nozzle body are rotatable in opposite directions about their longitudinal axes in response to a rotation of the rotary output shaft of the oscillator assembly.

[0118] Clause 20The sludge lance system of Clause 18 or 19, wherein at least one of the first drive shaft and the second drive shaft is rotationally lockable relative to the rail.

[0119] All patents, patent applications, publications, or other disclosure material mentioned herein, are hereby incorporated by reference in their entirety as if each individual reference was expressly incorporated by reference respectively. All references, and any material, or portion thereof, that are said to be incorporated by reference herein are incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as set forth herein supersedes any conflicting material incorporated herein by reference and the disclosure expressly set forth in the present application controls.

[0120] The present invention has been described with reference to various exemplary and illustrative aspects. The aspects described herein are understood as providing illustrative features of varying detail of various aspects of the disclosed invention; and therefore, unless otherwise specified, it is to be understood that, to the extent possible, one or more features, elements, components, constituents, ingredients, structures, modules, and/or aspects of the disclosed aspects may be combined, separated, interchanged, and/or rearranged with or relative to one or more other features, elements, components, constituents, ingredients, structures, modules, and/or aspects of the disclosed aspects without departing from the scope of the disclosed invention. Accordingly, it will be recognized by persons having ordinary skill in the art that various substitutions, modifications or combinations of any of the exemplary aspects may be made without departing from the scope of the invention. In addition, persons skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the various aspects of the invention described herein upon review of this specification. Thus, the invention is not limited by the description of the various aspects, but rather by the claims.

[0121] Those skilled in the art will recognize that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as open terms (e.g., the term including should be interpreted as including but not limited to, the term having should be interpreted as having at least, the term includes should be interpreted as includes but is not limited to, etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases at least one and one or more to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles a or an limits any particular claim containing such introduced claim recitation to claims containing only one such recitation, even when the same claim includes the introductory phrases one or more or at least one and indefinite articles such as a or an (e.g., a and/or an should typically be interpreted to mean at least one or one or more); the same holds true for the use of definite articles used to introduce claim recitations.

[0122] In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of two recitations, without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to at least one of A, B, and C, etc. is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., a system having at least one of A, B, and C would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to at least one of A, B, or C, etc. is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., a system having at least one of A, B, or C would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that typically a disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms unless context dictates otherwise. For example, the phrase A or B will be typically understood to include the possibilities of A or B or A and B.

[0123] With respect to the appended claims, those skilled in the art will appreciate that recited operations therein may generally be performed in any order. Also, although claim recitations are presented in a sequence(s), it should be understood that the various operations may be performed in other orders than those which are described, or may be performed concurrently. Examples of such alternate orderings may include overlapping, interleaved, interrupted, reordered, incremental, preparatory, supplemental, simultaneous, reverse, or other variant orderings, unless context dictates otherwise. Furthermore, terms like responsive to, related to, or other past-tense adjectives are generally not intended to exclude such variants, unless context dictates otherwise.

[0124] It is worthy to note that any reference to one aspect, an aspect, an exemplification, one exemplification, and the like means that a particular feature, structure, or characteristic described in connection with the aspect is included in at least one aspect. Thus, appearances of the phrases in one aspect, in an aspect, in an exemplification, and in one exemplification in various places throughout the specification are not necessarily all referring to the same aspect. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more aspects.

[0125] As used herein, the singular form of a, an, and the include the plural references unless the context clearly dictates otherwise.

[0126] Directional phrases used herein, such as, for example and without limitation, top, bottom, left, right, lower, upper, front, back, and variations thereof, shall relate to the orientation of the elements shown in the accompanying drawing and are not limiting upon the claims unless otherwise expressly stated.

[0127] The terms about or approximately as used in the present disclosure, unless otherwise specified, means an acceptable error for a particular value as determined by one of ordinary skill in the art, which depends in part on how the value is measured or determined. In certain aspects, the term about or approximately means within 1, 2, 3, or 4 standard deviations. In certain aspects, the term about or approximately means within 50%, 200%, 105%, 100%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.05% of a given value or range.

[0128] In this specification, unless otherwise indicated, all numerical parameters are to be understood as being prefaced and modified in all instances by the term about, in which the numerical parameters possess the inherent variability characteristic of the underlying measurement techniques used to determine the numerical value of the parameter. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter described herein should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0129] Any numerical range recited herein includes all sub-ranges subsumed within the recited range. For example, a range of 1 to 100 includes all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 100, that is, having a minimum value equal to or greater than 1 and a maximum value equal to or less than 100. Also, all ranges recited herein are inclusive of the end points of the recited ranges. For example, a range of 1 to 100 includes the end points 1 and 100. Any maximum numerical limitation recited in this specification is intended to include all lower numerical limitations subsumed therein, and any minimum numerical limitation recited in this specification is intended to include all higher numerical limitations subsumed therein. Accordingly, Applicant reserves the right to amend this specification, including the claims, to expressly recite any sub-range subsumed within the ranges expressly recited. All such ranges are inherently described in this specification.

[0130] Any patent application, patent, non-patent publication, or other disclosure material referred to in this specification and/or listed in any Application Data Sheet is incorporated by reference herein, to the extent that the incorporated materials is not inconsistent herewith. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

[0131] The terms comprise (and any form of comprise, such as comprises and comprising), have (and any form of have, such as has and having), include (and any form of include, such as includes and including) and contain (and any form of contain, such as contains and containing) are open-ended linking verbs. As a result, a system that comprises, has, includes or contains one or more elements possesses those one or more elements, but is not limited to possessing only those one or more elements. Likewise, an element of a system, device, or apparatus that comprises, has, includes or contains one or more features possesses those one or more features, but is not limited to possessing only those one or more features.