JP2022035865A - Screw fluid machine - Google Patents

Abstract

To improve the disassembling workability of a screw fluid machine that has a non-separation type bearing even in an item change screw rotor.SOLUTION: A screw fluid machine is equipped with a compressor casing 2 that stores a male rotor 40 and a female rotor 50 that are screw rotors, a discharge casing 3 connected with the compressor casing 2, and a separation type bearing and a non-separation type bearing rotatably supporting the screw rotor inside the compressor casing 2 and the discharge casing 3. Sleeves 14 and 16 are provided between a rotor shaft of the screw rotor and the non-separation type bearing, and the sleeves 14 and 16 are removed from the rotor shaft, thereby extracting the non-separation type bearing together from the discharge casing.SELECTED DRAWING: Figure 2

Description

The present invention relates to a fluid machine including a screw rotor.

As a screw fluid machine, there are screw compressors that compress the suction gas to generate compressed gas, screw pumps that pressurize and convey the suction liquid, and screw expanders that expand the inflowing compressed gas to generate rotational force. It has been known.

For example, a general screw compressor has a structure in which a screw rotor housed in a casing rotates and a volume formed from a tooth groove of the casing and the screw rotor is reduced to compress a gas.

As for the shape of the screw rotor, a screw rotor whose rotor specifications such as pitch and tooth profile cross-sectional shape are invariant (hereinafter, specification invariant screw rotor) is generally known, but a rotor such as pitch change and tooth profile cross-sectional shape change is generally known. There is also a screw rotor whose specifications have changed (hereinafter referred to as a screw rotor whose specifications have changed). For example, Patent Document 1 discloses a screw compressor equipped with a pitch change rotor. These specification-changing screw rotors can shorten the seal line and increase the discharge area compared to general specification-invariant screw rotors, so that it is possible to provide an energy-efficient fluid machine. ..

International Publication No. 2017/0755555

The screw rotor receives a load in the outer diameter direction of the rotor (hereinafter, radial load) and a load in the rotor axial direction (hereinafter, thrust load) from the compressed gas. The bearing that rotationally supports the screw rotor is installed in the casing so as to receive these radial load and thrust load, but in order to receive the thrust load, a ball bearing is installed on either the suction side or the discharge side. Has become common.

Since the inner and outer rings of the ball bearing are non-separable and are attached by tightening to the screw rotor shaft, it is necessary to use screws or hydraulic pressure when disassembling, but the above-mentioned specification change screw The rotor has problems in terms of operation such as disassembly workability. Specifically, in the case of a specification-immutable screw rotor, since the male and female screw rotors can move freely in the direction of the rotor axis, it is possible to remove the screw rotor by applying pressure separately for male and female during disassembly work. In the case of a specification change screw rotor, the male and female screw rotors cannot be moved separately in the rotor axial direction, so when disassembling, it is necessary to apply pressure to both male and female screw rotors at the same time to remove them, which is a special method for disassembling. Jig is required.

In the screw compressor equipped with the pitch change rotor described in Patent Document 1, the bearing configuration is not disclosed, and the improvement of disassembly workability is not considered.

It is an object of the present invention to provide a screw fluid machine having improved disassembly workability of a screw fluid machine having a non-separable type bearing even in a specification change screw rotor.

To give an example, the present invention has a compressor casing containing a male rotor and a female rotor which are screw rotors, a discharge casing connected to the compressor casing, and a screw rotor inside the compressor casing and the discharge casing. In a screw fluid machine equipped with a separate type bearing and a non-separable type bearing that rotationally supports the screw rotor, a sleeve is provided between the rotor shaft of the screw rotor and the non-separable type bearing, and the non-separable type bearing is provided by removing the sleeve from the rotor shaft. Also has a configuration that can be taken out from the discharge casing together.

According to the present invention, it is possible to improve the disassembly workability of a screw fluid machine having a non-separable type bearing.

It is a rotor axial sectional view of the screw compressor main body which carries the general specification invariant screw rotor. It is a rotor axial sectional view of the screw compressor main body which mounted the specification change screw rotor in Example 1. FIG. It is a block diagram of the sleeve in Example 1. FIG. It is a rotor axial sectional view of the screw compressor main body which mounted the specification change screw rotor in Example 2. FIG. It is a block diagram of the hydraulic sleeve in Example 2. FIG.

Hereinafter, examples of the present invention will be described with reference to the drawings.

First, a screw fluid machine equipped with a general specification invariant screw rotor will be described by taking a screw compressor as an example.

FIG. 1 is a rotor axial sectional view of a screw compressor main body equipped with a general specification invariant screw rotor. In FIG. 1, the compressor main body 1 including the compressor casing 2 containing the male rotor 4 and the female rotor 5 which are invariant specification screw rotors and the discharge casing 3 is connected to either the male rotor 4 or the female rotor 5. It is driven by a motor (not shown), and the gas is sucked in by the rotation of the motor. The sucked gas is sucked into a volume formed by each of the male and female rotors, the compressor casing 2, and the discharge casing 3, and as the volume decreases, the gas is compressed and the pressure rises.

When the gas is compressed, the male rotor 4 and the female rotor 5 receive a reaction force from the gas and receive a radial load and a thrust load. The bearings that rotate and support the screw rotor are the male rotor suction side bearing 6 and the female rotor suction side bearing 10 on the compressor casing 2 and the discharge casing 3 side, respectively, and the male rotor discharge side so as to receive these radial loads and thrust loads. The bearing 7 and the female rotor discharge side bearing 11 (hereinafter referred to as the discharge side bearings 7 and 11) are arranged. Here, in order to receive the thrust load, the structure is such that a non-separable ball bearing is installed on either the suction side or the discharge side of the gas. A separate bearing will be installed on the other side.

When ball bearings are arranged on the discharge side bearings 7 and 11, the presser plate 8 is arranged to prevent the discharge side bearing 7 from being pulled out from the shaft portion of the male rotor 4 during the operation of the compressor. The presser plate 8 is fastened to the male rotor 4 with a presser bolt 9. Similarly, in order to prevent the discharge side bearing 11 from being pulled out from the female rotor 5, a presser plate 12 is arranged, and the presser plate 12 is fastened to the female rotor 5 with a presser bolt 13.

When the compressor body 1 is disassembled for periodic bearing replacement, the discharge side bearings 7 and 11 are ball bearings, that is, non-separable bearings, so that the male rotor 4 and the female rotor 5 are the discharge casing 3. And is integrated via the discharge side bearings 7 and 11.

Since the rotor shafts of the male rotor 4 and the female rotor 5 and the discharge side bearings 7 and 11 are attached by tightening, they are disassembled by pushing out the male rotor 4 and the female rotor 5 using screw or hydraulic pressure. .. Specifically, first, the discharge casing cover 37 is removed from the discharge casing 3, the screw that fastens the compressor casing 2 and the discharge casing 3 is removed, and then the two screw holes into which the presser bolts 9 and 13 are inserted. By alternately tightening the two screws, which are disassembly jigs, according to the position, the discharge casing 3 and the discharge side bearings 7 and 11 are collectively removed from the male rotor 4 and the female rotor 5.

As described above, in the specification invariant screw rotor, the male and female screw rotors can be moved separately in the rotor axial direction, so that the male rotor 4 and the female rotor 5 can be individually disassembled. However, in the case of the specification change screw rotor, the male and female screw rotors cannot be moved separately in the rotor axial direction, so that the male rotor 4 and the female rotor 5 push out both at the same time for disassembly using pressure by screws or hydraulic pressure. There was a problem that it could not be easily disassembled because a special jig was required.

Therefore, the present embodiment for solving the above problems will be described below.

FIG. 2 is a rotor axial sectional view of a screw compressor main body equipped with a specification change screw rotor in this embodiment. In FIG. 2, the same reference numerals are given to the parts common to those in FIG. 1, and the description thereof will be omitted. In FIG. 2, the compressor main body 100 has a male rotor 40 and a female rotor 50 which are specification change screw rotors. Then, sleeves 14 and 16 are provided between the rotor shafts of the male rotor 40 and the female rotor 50 and the discharge side bearings 7 and 11, and the presser bolts 9 and 13 are provided in order to prevent the sleeves 14 and 16 from being pulled out. Is fastened to the male rotor 4 and the female rotor 5. Further, in order to prevent the discharge side bearings 7 and 11 from being pulled out from the sleeves 14 and 16, the structure is fixed by the bearing nuts 15 and 17.

3A and 3B are configuration views of sleeves 14 and 16 in this embodiment, where FIG. 3A is a perspective external view and FIG. 3B is an axial sectional view. As shown in FIG. 3, the sleeves 14 and 16 have a bolt fixing hole 31 for fixing the presser bolts 9 and 13, and two bearing extraction screw holes 32 on the same plane and on the same circumference. The number of screw holes 32 for extracting bearings may be at least two or more on the same circumference. Reference numeral 33 is a threaded portion for connecting the bearing nuts 15 and 17. Further, in the sleeves 14 and 16, the diameter of the end portion 34 coming to the bearing inner ring side of the sleeves 14 and 16 is larger than that of the other portions so as to be applied to the shoulder portion of the bearing inner ring of the discharge side bearings 7 and 11. ..

The disassembling operation of the compressor in this embodiment will be described below.

When disassembling the compressor body 100, first, the presser bolts 9 and 13 and the bearing nuts 15 and 17 are removed. Next, the bearing extraction screw is attached to the bearing extraction screw hole 32 provided in the sleeves 14 and 16. Then, by screwing the bearing extraction screw evenly, the sleeves 14 and 16 are moved so as to be removed from the rotor shaft by the action of the screw, and can be extracted from the discharge casing 3 together with the discharge side bearings 7 and 11. This makes it possible to easily disassemble the compressor body 100 without the need for a special jig for simultaneously extruding the male rotor 40 and the female rotor 50.

In this embodiment, as shown in FIG. 3B, the sleeves 14 and 16 have a structure such that they are applied to the shoulders of the bearing inner rings of the discharge side bearings 7 and 11, but the bearing inner ring has a structure. It does not matter if the shape does not cover the shoulder. In this case, the rotor shafts of the male rotor 40 and the female rotor 50 and the sleeves 14 and 16 need to be fast-fitted, and the discharge side bearings 7 and 11 and the sleeves 14 and 16 also need to be fast-fitted. The pulling force required to pull out the and 16 is larger than in the case of a structure such as that applied to the shoulder portion.

Further, in the present embodiment, the sleeves 14 and 16 are mounted on the specification changing screw rotor, but even if the sleeves 14 and 16 are mounted on the specification invariant screw rotor, the disassembly workability can be similarly improved.

Further, in this embodiment, the sleeves 14 and 16 are provided between the rotor shafts of the male rotor 40 and the female rotor 50 and the discharge side bearings 7 and 11, but the non-separable type bearings are arranged on the suction side. If this is the case, a structure in which a sleeve is provided between the rotor shaft and the suction side bearing may be used.

Further, in this embodiment, the rotor shafts of the male rotor 40 and the female rotor 50 are provided with sleeves 14 and 16, but neither is always necessary, and a structure in which a sleeve is provided on either one may be used. ..

Further, although the twin screw compressor is described in this embodiment, it may be a single screw compressor, a multi-rotor screw compressor, or the like.

As described above, according to the present embodiment, the bearing can be pulled out by removing the sleeve without requiring a special jig for disassembling the screw compressor having the non-separable type bearing. , A screw compressor with easy disassembly workability can be provided.

FIG. 4 is a rotor axial sectional view of a screw compressor main body equipped with a specification change screw rotor in this embodiment. In FIG. 4, the same reference numerals are given to the parts common to those in FIG. 2, and the description thereof will be omitted. In FIG. 4, the compressor body 110 differs from FIG. 2 in that the compressor main body 110 replaces the sleeves 14 and 16 with a hydraulic sleeve between the rotor shafts of the male rotor 40 and the female rotor 50 and the discharge side bearings 7 and 11. 18 and 20 are provided, and bushes 19 and 21 are used to prevent the hydraulic sleeves 18 and 20 from being pulled out, and the structure is fixed to the male rotor 4 and the female rotor 5 by the holding bolts 9 and 13. ..

5A and 5B are configuration views of hydraulic sleeves 18 and 20 in this embodiment, where FIG. 5A is a perspective external view and FIG. 5B is an axial sectional view. As shown in FIG. 5, the hydraulic sleeves 18 and 20 are provided with the hydraulic groove 36, and the hydraulic sleeve 18 is formed by injecting oil into the hydraulic groove 36 using a hydraulic jig and pressurizing the oil. And 20 have a structure that moves in the axial direction. Reference numeral 35 is an O-ring insertion groove for preventing oil leakage.

The disassembling operation of the compressor in this embodiment will be described below.

By injecting oil into the hydraulic grooves 36 provided in the hydraulic sleeves 18 and 20 using a hydraulic jig and pressurizing them, the hydraulic sleeves 18 and 20 move axially so as to be removed from the rotor shaft. However, the hydraulic sleeves 18 and 20 can be pulled out from the discharge casing 3 together with the discharge side bearings 7 and 11. This makes it possible to easily disassemble the compressor body without the need for a special jig.

As described above, according to the present embodiment, as in the first embodiment, the bearing can be pulled out by removing the sleeve without requiring a special jig for disassembling the non-separable type bearing. It is possible to provide a screw compressor that is easy to disassemble.

Although the examples have been described above, the present invention is not limited to the above-mentioned examples, and includes various modifications. For example, each of the above embodiments has been described in detail in order to explain the present invention in an easy-to-understand manner, and the present invention is not necessarily limited to the one including all the components described above. Further, it is possible to replace a part of the configuration of a certain embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of a certain embodiment. Further, it is possible to add / delete / replace a part of the configuration of each embodiment with another configuration.

1, 100, 110: Compressor body 2: Compressor casing 3: Discharge casing 4, 40: Male rotor 5, 50: Female rotor, 6: Male rotor suction side bearing, 7: Male rotor discharge side Bearings, 8, 12: Presser plate, 9, 13: Presser bolt, 10: Female rotor suction side bearing, 11: Female rotor discharge side bearing, 14, 16: Sleeve, 15, 17: Bearing nut, 18, 20: Hydraulic sleeve, 19, 21: Bush, 31: Bolt fixing hole, 32: Bearing extraction screw hole, 33: Thread cutting part, 34: End, 35: O-ring insertion groove, 36: Hydraulic groove, 37: Discharge casing cover

Claims (7)

A compressor casing containing a male rotor and a female rotor which are screw rotors, a discharge casing connected to the compressor casing, and a separate bearing that rotationally supports the screw rotor inside the compressor casing and the discharge casing. And in screw fluid machines with non-separable casings
A sleeve is provided between the rotor shaft of the screw rotor and the non-separable type bearing, and the non-separable type bearing can be pulled out from the discharge casing together by removing the sleeve from the rotor shaft. A screw fluid machine characterized by that. In the screw fluid machine according to claim 1,
The sleeve has a screw hole, and the sleeve can be removed from the rotor shaft by screwing a screw into the screw hole, and the non-separable type bearing can be taken out from the discharge casing together with the sleeve. Screw fluid machine. In the screw fluid machine according to claim 1,
The sleeve has a hydraulic groove, and by injecting oil into the hydraulic groove and pressurizing the sleeve, the sleeve can be removed from the rotor shaft and the non-separable bearing can be pulled out from the discharge casing together with the sleeve. A screw fluid machine characterized by that. In the screw fluid machine according to claim 1 or 2.
The sleeve is a screw fluid machine characterized in that the diameter of the end portion that comes to the bearing inner ring side so as to cover the shoulder portion of the bearing inner ring of the non-separable type bearing is larger than that of other portions. In the screw fluid machine according to claim 2,
The sleeve is fastened to the screw rotor with a presser bolt and is fastened to the screw rotor.
The sleeve is a screw fluid machine having a threaded portion and having a structure for preventing the non-separable type bearing from being pulled out from the sleeve by fastening a bearing nut to the threaded portion. In the screw fluid machine according to claim 3,
A screw fluid machine characterized in that the sleeve is fastened to the screw rotor with a presser bolt using a bush. In the screw fluid machine according to any one of claims 1 to 6.
The screw rotor is a screw fluid machine characterized by being a specification-changing screw rotor in which rotor specifications such as pitch and tooth profile cross-sectional shape are changed.

Images