Super large tonnage detachable hook

Abstract

The present invention discloses a super large tonnage detachable hook. The hook comprises: a hook rod, a hook shaft, a hook body, a spherical roller bearing, and a thrust spherical roller bearing. The hook also contains a connection component which connects the hook rod to the hook body. The split-type self-locking sleeve is integrally connected to the hook rod via the hook hoop holder. Meshing of the sleeve with the toothed sleeve of the hook rod is adopted to transmit the load, and the bearing capacity is greatly improved compared with the traditional screw connection. The hook of the present invention can withstand the downward and upward bi-directional load, which solves the problem that the traditional hook is prone to damage once it hits the ground. The hook is forged with 30CrNiMo8, which can lift an extremely large weight of more than 5,000 tons.

Claims

1. A super large tonnage detachable hook, comprising a movable pulley group, a hook rod, a hook shaft, a hook body, a spherical roller bearing and a thrust spherical roller bearing, wherein the detachable hook further comprises an embracing-type hoop holder assembly which connects the hook rod and the hook body and comprises a split-type sleeve, and a hoop holder set beneath the thrust spherical roller bearing; the hoop holder is fixedly connected to the hook rod via the split-type sleeve.

2. The super large tonnage detachable hook according to claim 1, wherein the hook body comprises two or more hook claws.

3. The super large tonnage detachable hook according to claim 1, wherein the hook rod and the hook body are each forged, heat treated, machined separately and then assembled together employing a bearing.

4. The super large tonnage detachable hook according to claim 3, wherein the hook rod and the hook body are integrally forged employing high-strength alloy steel 30CrNiMo8.

5. The super large tonnage detachable hook according to claim 1, wherein the embracing-type hoop holder assembly further comprises a bottom cover which engages the split-type sleeve to fix the hoop holder.

6. The super large tonnage detachable hook according to claim 1, wherein a groove is provided at a lower portion of the hook rod whereat the hoop holder is connected therewith, a bump corresponding to the groove is provided on the split-type sleeve, and the groove and the bump constitute a load bearing pair.

7. The super large tonnage detachable hook according to claim 1, wherein a central oil filling hole is provided at bottom of the hook rod for refueling from the bottom so that oil enters inside of the thrust spherical roller bearing via an oil groove for effective lubrication and increased service life of the thrust spherical roller bearing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is an assembly graph for a super large tonnage detachable hook disclosed by the present invention

(2) FIG. 2 is a schematic diagram of assembling structure of the super large tonnage detachable hook disclosed by the present invention

(3) FIG. 3 is a side view of FIG. 2

(4) FIG. 4 is a front view of a super large tonnage detachable hook disclosed by the present invention

(5) FIG. 5 is a top view of a super large tonnage detachable hook disclosed by the present invention

(6) FIG. 6 is a schematic diagram of the hook shaft of a super large tonnage detachable hook disclosed by the present invention

(7) FIG. 7 is a schematic diagram of the structure of the embracing-type hoop holder assembly of a super large tonnage detachable hook disclosed by the present invention

(8) FIG. 8 is a schematic diagram of the hook rod of a super large tonnage detachable hook disclosed by the present invention (a): front view, (b): side view

(9) FIG. 9 is a schematic diagram of the split-type self-locking sleeve of the super large tonnage detachable hook disclosed by the present invention (a): front view, (b): top view

(10) FIG. 10 is a three-dimensional view of the assembly process of the super large tonnage detachable hook.

(11) Reference signs in the drawings are designated as follows:

(12) 1: hook beam, 2: hook shaft, 3: hook rod, 4: hook retaining chain, 5: lock plate, 6: spherical roller bearing, 7: hook body, 8: thrust spherical roller bearing, 9: embracing-type hoop holder assembly, 10: bottom cover, 11: grease nipple, 13: chamfer, 21: sliding bearing, 22: shaft-end baffle, 31: hook rod head, 32: hook installation hole, 33: central oil hole, 34: hook rod tooth, 35: non-rotating groove, 36: hook rod shoulder, 71: hook tip, 72: chain lock hole, 91: split-type self-locking sleeve, 92: hoop holder, 93: bolt, 101: chain bracket, 103: stop block, 701: first hook claw, 702: second hook claw, 703: third hook claw, 704: fourth hook claw, 901: sleeve groove.

EMBODIMENTS

(13) The present invention will be further described hereinafter by elaborating a preferable embodiment with reference to FIG. 1-10.

(14) As shown in FIG. 1, a super large tonnage detachable hook disclosed by the present invention comprises a hook beam 1, a hook shaft 2, a hook rod 3, a hook retaining chain 4, a chain bracket 101, a sealing ring 102, a bearing cover 5, a hook body 7, a spherical roller bearing 6 arranged above the hook body 7, a thrust spherical roller bearing 8 arranged beneath the hook body 7, an embracing-type hoop holder assembly 9 arranged beneath the thrust spherical roller bearing 8, a bottom cover 10, a grease nipple 11, and an stop block 103. A bearing cover and an anti-groove jumping device which can rotate along with the hook body are provided on the spherical roller bearing 6.

(15) The hook beam 1 can be respectively connected to a movable pulley group, and each end of the connecting beam 1 is respectively connected with a movable pulley frame employing a pin shaft. A pin hole is provided at a middle portion of the hook beam 1, and the hook beam is connected with the hook shaft via the pin hole to connect the two movable pulleys so that the hook beam can be mounted with a lifting hook with a larger lifting capacity. FIG. 2 shows the detachable hook of the present invention with a single hook, the lifting capacity of which can be as high as 5,000 tons and above.

(16) The hook beam 1 adopts a semi-closed box structure, and the two ends of the hook shaft 2 adopt fixing shafts to avoid the connection of a shaft-locked plate which moves axially. This structure facilitates the assembling of the lifting hook.

(17) As shown in FIG. 4-5, the hook body 7 comprises two or more claws, four preferably. FIG. 5 shows the hook body 7 with four claws: a first hook claw 701, a second hook claw 702, a third hook claw 703, and a fourth hook claw 704. For the convenience of assembling, two claws can satisfy the requirement of lifting capacity. The probable stress concentration area at the bearing installation part undergoes special treatment. At the corner of the bearing mounting surface, the method of digging a Chamfer 13 is employed instead of the common rounded transition method, guaranteeing a smooth process for assembling bearing, as well as avoiding the problem of early cracking at this part of traditional detachable hooks. The whole bearing part of the hook is integrally forged, including the hook tip 71 and the hook body 7, modifying the welded structure of the hook tip and hook body of traditional hooks, and solving the problem that the hook tip is separated from the hook body under the pulling force of the wire rope of the stable hook during the offshore operation.

(18) As shown in FIG. 6, the hook shaft 2 is mounted above the hook rod 3 for steadier fixing and displacement avoiding. A sliding bearing 21 is provided at the connecting part between the hook shaft and the hook rod and a shaft-end baffle 22 is provided at the two ends of the hook shaft.

(19) The embracing-type hoop holder assembly 9 is employed to fixedly connect the hook rod 3 and the hook body 7. As shown in FIG. 7, the embracing-type hoop holder assembly 9 comprises a split-type self-locking sleeve 91 and a hoop holder 92 arranged beneath the thrust spherical roller bearing 8; wherein the split-type self-locking sleeve 91 is fixedly connected to the hook rod 3 by the hoop holder 92, thereby achieving the lifting capacity of several thousand tons. In some embodiments, the embracing-type hoop holder assembly 9 further comprises a bottom cover 10 employed to engage with the split-type self-locking sleeve 91 to fix the hoop holder 92.

(20) As shown in FIG. 8, an installation hole 32 is arranged on the rod head 31 for installing the hook shaft 2. A sliding bearing 21 is installed between the installation hole 32 on the upper portion of the hook rod 3 and the hook shaft 2, thereby guaranteeing the smooth right-and-left swinging of the lifting hook during operation, expanding the utilization scope of the lifting hook, reducing the horizontal force exerting on the hook rod 3, and enhancing the operation security thereof. A central oil hole 33 is arranged at the bottom of the hook rod 3 to refuel from the bottom so that oil enters the inside of the thrust bearing via the oil groove and an effective lubrication is achieved, thereby guaranteeing the service life of the bearing. A groove 34 is provided at a lower portion of the hook rod 3 where the hoop holder 92 is connected, a shoulder (as shown in FIG. 7) corresponding to the groove 34 is provided on the split-type self-locking sleeve 91, and the groove and the shoulder constitute a load bearing pair.

(21) The shoulder 36 above the hook rod 3 engages with the chain bracket 101 to ensure axial positioning, and transmits the vertical upward load to the chain bracket 101 through the hook body, and then to the shoulder on the hook rod and further to the connecting shaft when the hook lands on the ground, so as to ensure that the inner and outer rings of the thrust bearing will not be separated and that the bearing will not be damaged due to the reverse force. Thus, the problem that the traditional hook can only bear the downward load is solved. Further, the detachable hook of the present invention is suitable for special work requirements that the hook may need to enter the water and land during offshore operation.

(22) A rubber seal ring 102 is employed between the rotating and non-rotating parts, to prevent sea water or salt mist at sea from entering the inside of the hook bod, thereby protecting the bearing and extending the bearing life, to adapt to the special environmental conditions of offshore construction.

(23) The bottom cover 10 can also protect the fueling nozzle (i.e. the central oiling hole 33), and the grease nipple 11 in the middle portion of the bottom cover 10 can facilitate oil filling. The traditional detachable hooks are lubricated with oil from the side cover, and the oil quickly runs out from the gap of the cover, resulting in poor lubrication effect.

(24) A stop block 103 is installed on the bottom cover 10, which engages with a non-rotating groove 35 at the bottom of the hook rod 3 to stop the rotation of the hook rod, thereby ensuring that the hook body can rotate when the lifting parts need to be adjusted.

(25) The hoop holder 92 used to fix the split-type self-locking sleeve 91 is smooth and conical in shape for convenient hoisting in the installation process, and four threaded holes are set on the outside of the hoop holder which can be installed with four bolts 93 and used as hoisting points when necessary.

(26) The split-type self-locking sleeve 91 of the present invention is easy to install, and needs to be fixed only by the hoop holder and the bottom cover 10. Furthermore, only two shoulders are needed to constitute a load bearing pair with the two grooves of the hook rod, achieving a lifting capacity of several thousand tons. Compared with a traditional detachable hook using threaded connection, such a structure is simple and compact, with large loading capacity, easy to process, and convenient for assembling and dissembling.

(27) As is shown in FIG. 10, assembling of the detachable hook of the present invention is as follows: (a) the hook rod 3 is lifted vertically, (b) the hook body 7 is installed starting from bottom to top, (c) the hoop holder 92 is installed starting from bottom to top, (d) the split-type self-locking sleeve 91 is installed on the hook rod teeth 34, (e) the hoop holder 92 is put down to compress the split-type self-locking sleeve 91, and the chain bracket 101 is installed, (f) it is completed after the hook beam 1 is installed.

(28) The hook rod and the hook body of the detachable hook of the present invention are separately forged, heat treated, and machined, and then assembled ensemble employing a bearing, thereby solving the problems of huge structure and machining difficulty of integral hooks, and avoiding the problems of large amount of post-machining after integral forging and the waste of materials.

(29) In some embodiments, the hook rod, hook body, sleeve, and hoop holder are integrally forged separately employing a high-strength alloy steel 30CrNiMo, which must simultaneously satisfy the DIN-EN10250-3 “Alloy Special Steel” standard and the classification society's provisions on the impact toughness of forging materials at a low temperature, thus meeting the special requirements of offshore operations. The basic properties of the material are listed in Table 1 and Table 2.

(30) TABLE-US-00001 TABLE 1 Steel Grade and Chemical Compositions Name of Steel C Si Mn P.sub.max S.sub.max Cr Mo Ni V Name Value % % % % % % % % % 30CrNiMo8 1.6580 0.26-0.34 <0.40 0.3-0.6 0.035 0.035 1.8-2.2 0.3-0.5 1.8-2.2 \

(31) TABLE-US-00002 TABLE 2 Mechanical Properties in the State of Quenching and Tempering Breaking Impact Energy A.sub.min % Elongation KV.sub.min J Name of Steel Yield Strength Tensile Strength Longitudinal Transverse Longitudinal Transverse Name Value R.sub.emin N/mm.sup.2 R.sub.emax N/mm.sup.2 L TR L TR 30CrNiMo8 1.6580 590 800 12 8 40 20

(32) Compared with the commonly used hook materials DG20Mn, 35CrMo, 20CrMnMo, etc., 30CrNiMo8 has high strength and good performance, and can meet the special requirements of offshore construction. When 30CrNiMo8 is employed for the manufacturing of super tonnage integral hooks, the weight of the hook can be reduced, the overall performance of the hook can be better ensured, and the active load acting on the entire floating crane and the lifting vessel can be reduced, thereby the cost of the entire crane vessel can be reduced.

(33) The detachable hook of the present invention is integrally forged employing high-strength alloy steel. Compared with a cast hook, the forged hook has compact structure, few defects, high strength, and no residual slag during casting, thereby eliminating the risk of early cracking caused by casting. The detachable hook of the present invention is formed by machining after integral forging, and the dimensional accuracy is high. Moreover, compared with the traditional carbon gauging and sanding method, the process does not damage the heat treatment layer on the hook surface, and can avoid heat-treated cracks on the hook surface, which guarantees the heat-treated property of the hook surface; the strength of the hook body and the hardness of the hook surface are also ensured, and wear of the hook surface due to insufficient hardness during use can be avoided, and the service life of the hook is prolonged.

(34) In summary, the detachable hook of the present invention is integrally forged by high-strength alloy steel, with large lifting capacity of a single hook, high strength and good fatigue performance. It innovatively applies the connecting method of embracing-type hoop holder assembly, hoop holder and hook rod teeth to replace the thread connecting used by traditional hooks, to realize high bearing capacity, low processing difficulty and easy assembly. For the first time, the rubber seal ring is used on the detachable hook to prevent sea water or salt mist from entering the inside of the hook body under certain pressure, i.e. in certain water depth, to protect the bearing and prolong the bearing life. The unique two-way force transmission system enables the hook to transfer the reverse load to the hook shaft through the hook frame and the hook rod when the hook lands and reserve force occurs and when the hook mainly bears the downward lifting load, to avoid the separation of the thrust bearing and the damage to the bearing. The present invention thus solves various shortcomings and deficiencies in existing hooks, meeting the requirements in various adverse working conditions of offshore operation of large tonnage lifting hooks.

(35) Although the present invention has been described in detail by the preferable embodiments thereof, it should be understood that the foregoing description should not be construed as limiting. Various modifications and alterations of the present invention will be apparent to those skilled in the art. Therefore, the scope of the invention shall be defined by the appended claims.

(36) So far, the present invention has been exemplified by the aforementioned embodiments. Without violating the spirit and principle of the present invention, those skilled in the art can modify the technical scheme of the above embodiments or replace their technical features, and all modifications, alterations and improvements shall fall within the scope of power protection of the invention.