CN1004016B - Cylindrical casing of a turbomachine - Google Patents

Abstract

The utility model relates to a cylindrical casing of a turbine, on which there are serrations (14) protruding outwards on the pressure cover (7), and corresponding serrations (12) protruding toward the inner space (11) on the casing (1). In order to seal the housing (1), the cover (7) is pushed into the housing (1) and then turned at an angle, whereby every other serration (12, 14) engages with each other. After the pressure cover (7) is installed in the shell, the elastic seal (20) is installed, and the seal (20) is compressed by a detachable flange ring (21) fixed on the shell (1). . This simple design allows the cover (7) and housing (1) to be small in size, and the seal (20) can be replaced without removing the cover (7).

Description

Cylindrical casing of a turbomachine

The invention relates to a cylindrical housing for a turbomachine, for example a centrifugal pump or a compressor, the end of which is closed by a pressure cover. Resilient seals, such as flat rubber pads or "O" rings and metallic "C" rings, are provided around the separation gap between the housing and the pressure cap to seal the interior space of the machine, and a flange is fitted around the outer edge of the pressure cap.

In one known design, the housing or the housing which normally seals the machine housing from the drive end, in particular the housing of the pump housing or the pressure cover, is flanged and fastened to the housing by means of screws which can withstand large tensile forces and possibly nuts. The design of the housing cover with a resilient flat gasket or "O" gasket (Swiss Pat.562,405) between the cover and the housing to seal against outward pressure requires a protruding flange on the housing cover to which the tension screw is attached and the housing is larger and the entire cover must be removed to replace the seal.

Us patent 3,874,814 shows a barrel compressor with a cylindrical housing, in particular with an end cap. The housing has an internal annular groove for receiving a clamp formed by a first combination of shear keys formed of four parts held together by a ring key or flange ring which is screwed to the end cap.

The end cap, provided with a radial "O" ring, is inserted axially into the housing and retained by the circumferentially spaced shear keys. This design is very complicated and requires a great deal of effort to disassemble and assemble — such as when replacing the "O" ring. In addition, these radial "O" rings are exposed and can be damaged significantly when the cap is inserted into the housing.

It is therefore an object of the present invention to provide a simple, convenient and small size housing and cover arrangement in which the seal can be removed without removing the cover.

The present invention solves this problem by: the end face of the cartridge housing, to which the pressure cap is fitted, has radially inwardly projecting teeth with holes for insertion of the pump, the diameter of the pressure cap matching the inner diameter formed by the teeth of the housing and having outwardly projecting teeth which are circumferentially distributed and dimensioned to ensure that the cap can be fitted into the housing, and the flange ring surrounding the pressure cap is fitted to the end face of the housing by means of an intermediate radially and axially resilient seal, such as a rubber "O" ring or a metal "C" ring.

In the new design, the saw teeth of the housing overlap with the saw teeth of the cover by turning the pressure cover so that the saw teeth couple to withstand the hydraulic pressure. The radial and axial sealing rings, which are pressed by the flange ring, are inserted after the drawer assembly comprising the rotor, the stator and the housing cover is inserted into the housing and the cover just mentioned is rotated, ensuring the sealing of the pump. Thus, firstly, the new design does not require a raised flange and a large amount of tension of the screws, so that the pressure cap and the housing can be made smaller than before, and secondly, the risk of damaging the sealing ring is prevented. Furthermore, the removal of the pressure cap is no longer necessary when the seal is removed due to leakage.

If holes are made in some of the saw teeth of the pressure cover, the assembly of the rotor, stator and pressure cover into a drawer-type assembly can be facilitated by screwing bolts into the holes in the stator of the pump.

Furthermore, the axial through-holes in the saw-teeth of the housing allow the pressure between their teeth to be released when the lid is removed from the housing. Every other tooth can be brought into tight engagement with each other by means of the pressure of the hydraulic medium before they are released from each other by rotating against each other.

The invention will be more precisely described below with reference to an embodiment with the attached drawings:

fig. 1, which is a view taken roughly from the middle plane of the casing or pressure cover, shows a detail of an actual cylindrical pump casing.

Fig. 2, an end view of the cylindrical housing as seen from the right in fig. 1, with the drawer assembly removed.

Fig. 3, the stator and rotor are removed from an end view of the pressure cap in the opposite direction to fig. 2 and looking from the left.

In addition to the shaft 2 and one of the rotors 3 and the pressure relief piston 4 mounted thereon, the cylindrical housing (fig. 1) has a stepped housing 5 and a stator 6 on its last step, which cylindrical housing is closed from the right in fig. 1 by a housing cover 7 (or pressure cover) which accommodates an open pressure compensation tube 8. In the inner space near the axis of the pressure cover 7, a pressure relief bushing 9 surrounds the pressure relief piston 4, and a sliding sealing ring 10 is schematically shown. In the region of the open shell end, at the edge of the interior space 11 of the shell 1, as shown in fig. 2, there are distributed teeth which project radially inwards and which are distributed uniformly over the circumference at a distance from one another 12. Every second tooth 12 is provided with an eccentrically arranged hole 13 for connection to a pressure pipe of a hydraulic system, not shown, as described above, whereby the tooth 12 is removed from the tooth 14 of the pressure cover 7 when it is removed (the tooth 14 being behind the tooth 12 in the assembled state).

The teeth 14 of the pressure cap are distributed along the outer circumference to project outwards, and the diameter of the cap is adapted to the inner diameter formed by the saw teeth of the housing. The teeth 12 and 14 are shaped and positioned to cooperate with each other so that the teeth 14 of the pressure cap 7 can enter the housing from between the teeth 12, and, after releasing the pressure cap 7 from the stator 5, 6, the teeth 14 can be turned by a rotation, in this case by pi/8, to the back of the teeth 12.

The teeth 14 are also perforated with a series of through holes 15 through which bolts 16 (fig. 1) are screwed when the rotors 2, 3, 4, stators 5, 6, 9 and pressure cover 7 are assembled together as a drawer-type assembly. To secure the lid 7 to the drawer assembly, bolts 16 are screwed into threaded holes 18 in a fishplate 17, which fishplate 17 is located on the stator 6 on the last step. Naturally, after the assembly is placed in, and before the above-described rotation method is used to engage every other tooth 12 and 14 with each other, the bolt 16 is not tightened.

For the axial and radial sealing of the interior 11, annular grooves 19 are formed on the outer circumference of the pressure cover 7 and on the housing end face, in which "O" rings are inserted as elastic seals. The sealing surface for the co-operation with the "O" ring is formed by a flange ring 21 which closes the gap between the housing 1 and the pressure cover 7, which is placed on the housing 1 and fastened by screws 22 in threaded holes 23.

The positioning pins 25, which are fixed in the holes 24 (fig. 2) on the end face of the casing, ensure that the cover 7 is always in the same correct position with respect to the casing 1 after each removal and re-installation, and thus the correct assembly position of the flange ring 21 with respect to the casing 1, and that the relative position of the cover 7 and the flange ring 21 is adjusted by means of wedges 26, which are placed in corresponding cut-outs of these two parts.

Claims (4)

1. A cylindrical casing of a turbine, having a pressure cover at one end thereof and a flange ring sleeved on the outer edge of the pressure cover, wherein the present invention is characterized in that a serration (12) protruding inwards is provided in a hole (11) for assembling the pressure cover (7) at one end of the cylindrical casing (1), the diameter of the pressure cover (7) matches the inner diameter formed by the casing serration (12), the pressure cover has serrations (14) protruding outwards, the serrations (12, 14) are arranged in the circumferential direction and their dimensions ensure that the pressure cover (7) can be fitted into the cylindrical casing (1), and the flange ring (21) is fixed to the end face of the cylindrical casing (1) via an intervening radial and axial elastic seal (20), such as an elastic "O" ring or a metal (C) ring. 2. A cylindrical housing according to claim 1, characterised in that at least some of the teeth of the pressure cover are bored with axial through holes. 3. A cylindrical housing according to claim 2, characterized in that the pressure cover (7) and the stator (5, 6) of the machine are formed into a drawer-type assembly by means of bolts (16) passing through the holes (15) on the serrations (14) of the pressure cover, thereby facilitating assembly. 4. A cylindrical housing according to claim 1, wherein at least some of the housing teeth are bored with axial through holes.

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