Device for treating metal workpieces with cooling gas

Abstract

In order to achieve an increase in energy efficiency and a faster quenching of the workpieces, a device according to the invention is proposed for the treatment of metallic workpieces with cooling gas, comprising a horizontally arranged cylindrical housing (1) with at least one closable opening for the introduction and extraction of the workpieces to be treated, with a quenching chamber (2) located inside the housing (1) for receiving the workpieces to be treated, with two high-performance fans (5 and 6) arranged laterally and outside the quenching chamber (2) for guiding a cooling gas through the quenching chamber (2) and with two heat exchangers (11 and 12) for cooling the cooling gas, that heat exchanger (11 or 12) is respectively associated with a high-performance fan (5 or 6) and that closable guide devices (17 or 18) are arranged above and below the quenching chamber (2).

Claims

1. A device for the treatment of metallic workpieces with cooling gas, comprising a horizontally arranged cylindrical housing (1) with at least one closable opening for the insertion or extraction of the workpieces to be treated, with a quenching chamber (2) lying within the housing (1) for receiving the workpieces to be treated, with two fans (5 and 6) arranged laterally and outside the quenching chamber (2) for guiding a cooling gas through the quenching chamber (2) and with two heat exchangers (11 and 12) for cooling the cooling gas, characterized in that a respective heat exchanger (11 or 12) is positioned to receive the cooling gas from one of the fans (5 or 6) and that movable gas flow guide devices (17 and 18) are arranged above and below the quenching chamber (2), wherein the movable gas flow guide devices each comprise a guide box (19, 20) and a guide element (21, 22), said guide boxes being connected to each other by connecting struts (27, 28), said guide boxes being movable by a traversing unit for opening or closing suction openings (29) for each fan (5, 6), one of said suction openings being positioned above and laterally next to the quenching chamber (2) and another of said suction openings being positioned below and laterally next to the quenching chamber, whereby the gas flow guide elements (21, 22) are operable to.

2. The device according to claim 1, characterized in that the heat exchangers (11 and 12) are ring-shaped.

3. The device according to claim 2, characterized in that each ring heat exchanger (11 or 12) surrounds an impeller (9 or 10) of the associated fan (5 or 6).

4. The device according to claim 1 characterized in that each guide box (19 or 20) has two side walls (23 and 24), between which guide plates (25) are arranged, which form guide channels (26) for guiding the cooling gas.

5. The device according to claim 4 characterized in that a traversing path of the guide boxes (19 and 20) is dimensioned such that the suction openings (29) are closed by the side walls (23 and 24) of one of the guide boxes (19, 20) when the guide channels (26) are opened by the other guide box (20, 19).

6. The device according to claim 1 characterized in that the guide elements (21 and 22) are fastened on the inside of the housing (1).

7. The device according to claim 6 characterized in that each guide element (21 or 22) is configured v-shaped in cross-section, that the surface of the guide box (19 or 20) facing the guide element (21 or 22) is designed such that guide boxes (19 or 20) whose guide channels (26) are closed abut the guide element (21 or 22).

Description

SHORT DESCRIPTION OF THE DRAWING

(1) For further explanation of the invention, reference is made to the drawing, in which several different embodiments are shown in simplified form. It shows:

(2) FIG. 1 shows a cross-section through a device constructed according to the invention for treating metallic workpieces,

(3) FIG. 2 shows a longitudinal section in a perspective view of the device according to FIG. 1,

(4) FIGS. 3a to c show individual positions of the guide boxes to achieve a flow reversal of the cooling gas.

DETAILED DESCRIPTION OF THE DRAWING

(5) The device according to the invention comprises a cylindrical, single-walled, horizontal housing 1, on the at least one of the end face of which, not shown here, a door or a slider is provided for closing.

(6) The quenching chamber 2 is centrally located within the housing 1, the quenching chamber being bounded at its two longitudinal sides by baffles 3 and 4. In the quenching chamber 2, two laterally arranged backing strips are provided, on which the workpieces to be quenched are deposited. These backing strips leave open a maximum flow cross-section to the workpieces. The quenching chamber itself is in this case dimensioned such that it encloses the workpieces to be quenched as closely as possible.

(7) Laterally next to the quenching chamber 2, two horizontally arranged fans 5 and 6 are provided, the drive motors 7 and 8 of which (only partially visible) are connected via gas-tight flange connections directly to the housing 1. The drive shafts of the two fans are arranged in alignment with each other. The impellers of the high-power fans 5 and 6 are designated 9 and 10. The fans 5 and 6 are configured as high-performance fans.

(8) A ring heat exchanger 11 and 12 is attached in each case to the impellers 9 and 10. These ring heat exchangers can be constructed in one or more parts, round or crescent-shaped. The ring heat exchangers are constructed in four parts in the illustrated embodiment. A baffle housing, not shown here, for the low pressure loss guidance of the cooling gas is arranged around the heat exchangers.

(9) In each case, an intake tract 13 and 14 is located between the two baffles 3 and 4 and the suction region of the fans 5 and 6, which intake tract is limited on the side of the fan 5 and 6 by an inner partition plate 15 and 16.

(10) Above and below the quenching chamber 2, a guide device 17 and 18 is provided on the entire width and length of the quenching chamber. Each guide device 17 and 18 comprises a guide box 19 and 20 and an associated guide element 21 and 22. The guide elements 21 and 22 are formed v-shaped in cross-section and rigidly fastened to the inside of the housing 1.

(11) Each guide box 19 and 20 has closed side walls 23 and 24. Guide plates 25 are arranged in each guide box 19 and 20 parallel and perpendicular to the side walls 23 and 24 so that honeycomb rectangular guide channels 26 (FIG. 2) are formed for the cooling gas. The guide plates 25 are designed such that they correspond in cross-section (FIG. 1) to the shape of the guide elements 21 and 22.

(12) Both guide boxes 19 and 20 are connected to each other by lateral connecting struts 27 and 28. These connecting struts are arranged so as to allow a nearly lossless flow connection from the quenching chamber to the intake tracts 13 and 14. A traversing unit, not shown, makes it possible to move the two guide boxes, as will be further explained below.

(13) FIG. 2 shows a perspective longitudinal section through the device according to the invention. Here, on the one hand, the construction and the arrangement of the guide channels 26 can be seen very clearly and, on the other hand, one of the four suction openings 29 of the intake tract 14. It is located above the quenching chamber 2. A further suction opening, not shown, is located below the quenching chamber. The intake tract 13 has corresponding suction openings.

(14) Furthermore, FIG. 2 shows the arrangement of shielding plates 30, which are arranged above and below, on the front side and the rear side of the quenching chamber 2 and extend from these to the inside of the housing 1. This prevents cooling gas from flowing in this by bypassing the cooling channels 26 of the front side and back side of the quenching chamber. This ensures that the quenching chamber 2 is always only flowed through vertically.

(15) The quenching chamber 2 is loaded through the front opening by means of an external device with a batch of workpieces that has been previously heated in a separate device and optionally carbonized. The quenching chamber 2 is unloaded either through the front opening or through a rear opening, if it is a continuous quenching chamber.

(16) In FIGS. 1 and 2 and 3a, the cooling gas flows through the quenching chamber from bottom to top. This is indicated by a flow arrow 31. For this purpose, the guide device 17 is located in its upper end position, i.e., the upper guide box 19 abuts its guide element 21. As a result, its guide channels 26 are closed and therefore can not be flowed through. At the same time, the lower guide box 20 is spaced from its guide element 22, such that its guide channels 26 can be flowed through freely. The two upper suction openings 29 are released to the two intake tracts 13 and 14 by this position of the two guide elements 17 and 18, while the side walls 23 and 24 of the lower guide box 20 close the lower two suction openings 29.

(17) The cooling gas heated by the hot workpieces in the quenching chamber is therefore divided and suctioned by the two upper suction openings 29 into two partial flows, led to the two high-performance fans 5 and 6 and pushed by them radially through the ring heat exchangers 11 and 12, wherein it is cooled. It then flows through the spiral guide housing running around the ring heat exchangers 11 and 12 and, via the guide element 22, deflected by the lower guide box 20 from below into the quenching chamber 2. The two partial flows of the cooling gas are brought together again before and in the guide box 20. The guide channels 26 align the flow of the cooling gas vertically again.

(18) If the flow direction of the cooling gas is now to be reversed (contrary to the flow direction in FIGS. 1, 2 and 3a), the traversing device for the two guide boxes 19 and 20 is activated. This shifts the guide boxes from their upper position (FIG. 1, 2, 3a) via a central position (FIG. 3b), in which both guide boxes are removed from their guide elements, to the lower position (FIG. 3c). In this position, the guide channels 26 are closed in the lower guide box 20 by the guide element 22. At the same time, the upper suction openings 29 are closed by the side walls 23 and 24 of the upper guide box 19, while the lower suction openings 29 are released to the intake tracts 13 and 14. Since the upper guide box 19 is now positioned away from its guide element 21, the guide channels 26 are opened in this guide box 19.

(19) The cooling gas thus now flows via the two lower suction openings 29 into the intake tracts 13 and 14. From there it flows on via the impellers 9 and 10 of the high-performance fan 5 and 6 radially through the ring heat exchangers 11 and 12. Via the spiral guide housing, now recooled cooling gas now flows vertically down through the quenching chamber 2, after which the two partial flows had been previously deflected by the guide element 21 and had been guided and directed together by the guide channels 26 in the guide box 19. This is illustrated in FIG. 3c by the flow arrow 32.

(20) As a result of this simple adjustment of the guide devices 17 and 18, a flow reversal of the cooling gas is rapidly achieved if it requires the contour of the workpieces to be quenched.

LIST OF REFERENCE NUMBERS

(21) 1 housing 2 quenching chamber 3 side wall of 2 4 side wall of 2 5 fan 6 fan 7 drive motor of 5 8 drive motor of 6 9 impeller of 5 10 impeller of 6 11 ring heat exchanger 12 ring heat exchanger 13 intake tract of 5 14 intake tract of 6 15 inner partition plate of 13 16 inner partition plate of 14 17 upper guide device 18 lower guide device 19 guide box of 17 20 guide box of 18 21 upper guide element 22 lower guide element 23 side walls of 18, 19 24 side walls of 18, 19 25 guide plates in 18, 19 26 guide channels 27 connecting struts 28 connecting struts 29 suction openings 30 shielding plates 31 flow arrow 32 flow arrow