JPH0423190B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a cooling device for a discharge piping system of a compressor, and particularly to an aftercooler of an oil-free compressor.
This invention relates to a compressor discharge piping system cooling device suitable for simplifying systems after the compression outlet, such as check valves and air coolers.

[Prior Art] In a conventional oil-free screw compressor, the air in the discharge side piping is released into the atmosphere during no-load startup, and the pressure is maintained in the discharge pipe by the vacuum pressure on the suction side. It is well known that the compression ratio is increased to prevent the temperature of the discharged air from rising abnormally.

First, a conventional cooling means for a discharge piping system of a compressor will be explained with reference to FIGS. 6 and 7.

FIG. 6 is a block diagram of an aftercooler employed in a conventional oil-free screw compressor, and FIG. 7 is a schematic cross-sectional view of a conventional shell-and-tube cooler.

The device shown in Figure 6 is described in Japanese Patent Application Laid-Open No. 59-93985, and there is one in which the check valve and aftercooler are integrated, but the air cooler (not shown) is installed separately. ing.

In FIG. 6, 6A is a check valve provided at the top of the aftercooler shell 16A, 18A is a cooling pipe constituting the aftercooler, and the compressed air that has flowed into the aftercooler shell 16A is
It is cooled by exchanging heat with the cooling water flowing through the cooling pipe 18A.

Further, the shell-and-tube type cooler shown in FIG. 7 has a configuration in which an air cooler and an aftercooler are integrated.

That is, in FIG. 7, 6B is the cover 25.
17B is a cooling pipe for the air cooler, 18B is a cooling pipe for the aftercooler,
Each of these cooling pipes is arranged within the shell 16B,
It is fixed to tube plates 19B at both ends of the shell.

Cooling water flows in the shell 16B to cool the compressed air in each of the cooling pipes 17B and 18B.

[Problems to be Solved by the Invention] In the above-mentioned aftercooler shown in FIG. 6, since the air blowing cooler is installed separately, extra equipment arrangement space is required. In addition, since the air is configured to circulate within the shell 16A of the aftercooler,
Unless you use stainless steel etc. for shell 16A,
There is a problem that rust gets mixed into the discharged air.

On the other hand, in the shell-and-tube cooler shown in FIG. 7, the check valve 6B is installed inside the cover 25, so maintenance of the check valve 6B takes time.

In addition, the cooling pipes 17B and 18B are straight pipes with shell 1
Since it is fixed to the tube plate 19B at both ends of 6B,
It is difficult to absorb thermal expansion of the cooling pipes, and water leaks easily from the joints due to thermal stress applied to the joints between the tube plate 19B and the cooling pipes 17B and 18B, resulting in a lack of reliability. Furthermore, since the check valve 6B is installed vertically, there is a problem that the movement of the valve plate tends to become unstable.

The present invention has been made to solve the problems of the prior art described above, and aims to integrate the equipment configuration, simplify the discharge piping system of the compressor, save space, and facilitate maintenance. It is an object of the present invention to provide a cooling device for a compressor discharge piping system that can ensure reliability.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the compressor discharge piping system cooling device according to the present invention includes a check valve connected to the discharge side of the compressor, A compressor comprising an air discharge cooler that cools the air in the discharge piping that is to be discharged to the atmosphere when the compressor is started with no load, and an aftercooler that cools the compressed air that is to be supplied to the demand side when the compressor is started with a load. In the discharge piping system device, the cooling pipes for the blast cooler and aftercooler are provided in the same shell, and the header connected to the shell is partitioned into four chambers, and each of the blast cooler and aftercooler is divided into four chambers. A communication hole is provided between two adjacent chambers through which the cooling pipe passes, and the above-mentioned check valve is installed in this communication hole, and the remaining two of the four chambers communicate with the cooling pipe of the air discharge cooler. The other chamber is connected to the air discharge pipe, and the other chamber communicating with the cooling pipe of the aftercooler is connected to the compressed air pipe on the demand side.

In addition, the shell is arranged so that its longitudinal direction is horizontal, and each cooling pipe of the air cooler and aftercooler in this shell is a U-shaped tube, and the upper part of the U-shaped tube is compressed. air inlet side,
The lower part of the U-shaped tube is connected to the outlet side of the compressed air.

[Operation] The cooling operation of the compressor discharge piping system by the above-mentioned technical means will be explained.

The air discharged from the compressor (compressed air) first enters chamber A of the four chambers of the head shown in FIG. 1, which will be described later. Room A and room D communicate with each other via a blow-off cooler cooling pipe 17 shown in FIG. When the operation starts, the air release valve opens and the air upstream from the check valve passes through the air air cooler cooling pipe 17.
It is cooled by exchanging heat with the cooling water flowing inside the shell and released into the atmosphere. At this time, the check valve prevents the air from chamber B onwards from flowing back into chamber A, ensuring no-load operation of the compressed air.

On the other hand, during load operation, the air release valve closes and air enters the adjacent chamber B from chamber A through the check valve.
It passes through the aftercooler cooling pipe 18 shown in FIG. 3, enters the cooled chamber C, and is supplied to the demand side.

[Example] Hereinafter, each example of the present invention will be described with reference to FIGS. 1 to 5.

FIG. 1 is a longitudinal cross-sectional view of a header portion constituting a discharge piping system cooling device according to an embodiment of the present invention;
2 is a sectional view taken along the line X-X in FIG. 1, FIG. 3 is a longitudinal sectional view of the cooler section connected to the header in FIG. 1, and FIG. 4 is another embodiment of the present invention. FIG. 5 is a system diagram showing the overall configuration including the piping system of a general two-section oil-free screw compressor.

First, in Fig. 5, 1 is a 1-stage compressor, 2 is a 2-stage compressor, and 3 is a 1-stage compressor 1 and a 2-stage compressor 2.
Intercooler installed in the discharge piping system between
is an aftercooler provided in the discharge piping system of the two-stage compressor 2, 5 is an air discharge cooler provided in the discharge piping system of the two-stage compressor 2, 6 is a check system, and 7 is the first-stage compressor 1
8 is an air cylinder, 9 is a discharge valve, 10 is a silencer, 11 is a suction filter, 12 is a discharge pipe, 13 is a discharge from the discharge cooler 5 to the discharge valve 9. Air discharge piping for piping system, 1
4 is a compressed air piping on the demand side.

The air that has passed through the suction filter 11 is pressurized by the first-stage compressor 1, cooled by the intercooler 3, and then sucked into the second-stage compressor 2. The air further pressurized by the two-stage compressor 2 passes through a check valve 6, is cooled by an aftercooler 4, and is discharged through a compressed air pipe 14 on the demand side.

On the other hand, capacity control is performed by opening and closing the suction throttle valve 7, and during no-load operation, the discharge valve 9 is opened at the same time as the suction throttle valve 7 is closed. In this embodiment, an air cylinder 8 is used to open and close these two valves. When the air release valve 9 opens, the air between the suction throttle valve 7 and the check valve 6 passes through the air air cooler 5 and is emitted to the atmosphere via the silencer 10.

The air discharge cooler 5 is pressurized by the two-stage compressor 2 to 150
It is provided to cool the air that has reached a high temperature of ~200°C and release it into the atmosphere, and to prevent parts used in the air release valve 9, such as rubber sheets (not shown) in particular, from being exposed to the high-temperature air. .

The configuration of the cooler in one embodiment of the present invention is shown in the third example.
As shown in the figure.

In FIG. 3, a shell 16 is provided with an inlet 16a and an outlet 16b for circulating cooling water, and the shell 16 is arranged so that its longitudinal direction is horizontal. Reference numeral 17 denotes a cooling pipe for an air cooler arranged outside forming a U-shaped pipe from the upper part to the lower part of the shell 16 (hereinafter referred to as an air cooler cooling pipe); 18 refers to an inner side of the air cooler cooling pipe 17; ,
Cooling pipes 19 for aftercoolers (hereinafter referred to as aftercooler cooling pipes) arranged in U-shaped tubes in the second and third stages in FIG. 3 are fixed to the side of the shell, and each cooling pipe is This is a tube plate that supports the tubes.

Next, according to FIGS. 1 and 2, the tube sheet 1
The configuration of the header 15 attached to the header 9 will be explained.

As shown in FIGS. 1 and 2, inside the header 15 there are 4
It is divided into two rooms, A, B, C, and D from the top. The A chamber includes a compressed air inlet 15 a connected to the discharge pipe 12 , and the A chamber and the D chamber communicate with each other via an air discharge cooler cooling pipe 17 .

A communication hole 22 is provided between two adjacent rooms, A room and B room, to communicate these two rooms.
A check valve 6 is attached to the valve 2. That is, the check valve 6, via the gasket 23,
It is fixed by a holder 24.

A hole 20 having a diameter larger than at least the outer diameter of the check valve part (including the holder 24) is provided in the outer wall of the shell 15, which is the upper part of the check valve 6, for attaching the check valve 6 and the holder 24. A cover 21 is bolted into this hole 20.

In addition, the B chamber and C chamber are the aftercooler cooling pipe 1.
It communicates via 8. The C chamber is provided with a compressed air outlet 15c to be connected to the compressed air piping 14 on the external demand side. Further, the D chamber communicating with the air discharge cooler cooling pipe 17 is provided with an outlet 15d to be connected to the air discharge pipe 13.

Next, the operation of such a discharge piping system cooling device will be explained using the two-stage oil-free screw compressor shown in FIG. 5 as an example.

The discharge air of the two-stage compressor 2 enters the A chamber from the discharge pipe 12 through the inlet 15a of the header 15.

When each compressor enters a no-load operation, the air release valve 9 opens, and the air upstream from the check valve 6 passes through the air air cooler cooling pipe 17 as shown by the arrow and flows through the shell 16 for cooling. It is cooled by heat exchange with water, flows from the D chamber through the outlet 15d to the air release pipe 13, and is discharged to the atmosphere via the air release valve 9 and the silencer 10. At this time, the check valve 6 prevents the air from chamber B onwards from becoming A.
Prevents backflow into the room and ensures no-load operation of the compressor.

On the other hand, during load operation, the air release valve 9 is closed, and the compressed air that enters the A chamber from the inlet 15a of the header 15 passes through the check valve 6 and enters the B chamber, where it flows into the aftercooler cooling pipe as shown by the arrow. Through 18, Ciel 1
It is cooled by exchanging heat with the cooling liquid flowing through the C
The air is supplied from the chamber to the compressed air piping 14 on the demand side via the outlet 15c.

According to this embodiment, the following components are omitted compared to the conventional technology.

(1) Case that houses the check valve (2) Piping that connects the check valve and aftercooler (3) Air discharge cooler shell (4) Piping that connects the ventilation cooler and check valve (5) Air discharge Cooling water piping to the cooler Specifically, if you include the joints among the above components, more than 20 separate parts will be omitted, which is economical, and reliability is achieved by preventing leakage from connections. Improvements in performance, ease of maintenance, etc. are achieved.

Further, according to the header 15 of this embodiment, since the independent cover 21 is provided above the check valve 6,
Maintenance such as inspection and replacement of the check valve 6 can be easily performed by removing only the cover 21 and the holder 24 without removing any piping of the air system or piping of the cooling water system.

Furthermore, during check valve maintenance, it is necessary to check whether the check valve is performing its check function satisfactorily, but in the past, when the compressor was operated and the
The header 1 of this embodiment was previously determined indirectly by measuring the pressure in the part corresponding to the chamber.
According to No. 5, even if the compressor is connected to the user's line and the compressor is stopped, the cover 2
If 1 is removed, leakage (backflow) from the check valve 6 can be visually observed. Therefore, it is possible to make a reliable judgment when maintaining the check valve 6, and even if there is an abnormality in the check valve, it cannot be determined unless the check valve is operated in that condition. The advantage is that there is no need to drive in dangerous conditions.

Next, another embodiment of the present invention will be described with reference to FIG.

The cooler shown in FIG. 4 differs from the cooler shown in FIG. 3 in the arrangement of the cooling pipes. That is, as shown in FIG. 4, inside the shell 16',
Aftercooler cooling pipes 18' forming a U-shaped pipe from the upper part to the lower part are arranged on the outside, and on the inside thereof,
Air cooler cooling pipes 17' forming a U-shaped tube are arranged.

The header connected to such a shell 16' is
Although not particularly shown, the air discharged from the compressor is made to flow into chamber B of the four chambers in the header shown in FIGS. The chamber C is connected to the air release pipe 13 on the air release valve side, and the D room is connected to the compressed air pipe 14 on the demand side.

In this way, it is possible to perform exactly the same operation as in the previously described embodiment, and the same effects can be expected. In addition, since the length of the ventilation cooler cooling pipe 17' can be freely selected, The temperature of the air after passing through the wind cooler cooling pipe 17' can be arbitrarily designed, and a unique effect is brought about which is advantageous in cases where it is desired not to generate condensate at the outlet of the wind cooler.

In each of the above-mentioned embodiments, an example of a two-stage oil-free screw compressor was explained, but the present invention is not limited to this. This cannot be prevented from being applied to other compressors within the expected range.

[Effects of the Invention] As described above, according to the present invention, the equipment configuration is integrated, the compressor discharge piping system is simplified, space is saved, and maintenance is facilitated, and reliability is improved. It is possible to provide a compressor discharge piping system cooling device that can be secured.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a header portion constituting a discharge piping system cooling device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line X-X in FIG. 1, and FIG. 1st
Vertical sectional view of the cooler section connected to the header in the figure, No. 4
5 is a longitudinal sectional view of a cooler section according to another embodiment of the present invention, FIG. 5 is a system diagram showing the overall configuration including the piping system of a general two-stage oil-free screw compressor, and FIG. FIG. 6 is a block diagram of an aftercooler employed in a conventional oil-free screw compressor, and FIG. 7 is a schematic cross-sectional view of a conventional shell-and-tube cooler. 2... Two-stage compressor, 6... Check valve, 9... Discharge valve, 12... Discharge piping, 13... Discharge piping, 14
... Compressed air piping, 15 ... Header, 15a ...
Inlet, 15c, 15d...Outlet, 16,1
6'...Ciel, 17, 17'...Blowout cooler cooling pipe, 18, 18'...Aftercooler cooling pipe, 2
0... hole, 21... cover, 22... communicating hole.

Claims (1)

[Scope of Claims] 1. A check system connected to the discharge side of the compressor, a blower cooler that cools the air in the discharge pipe to be discharged to the atmosphere when the compressor is started with no load, and a load on the compressor. In a compressor discharge piping system cooling device comprising an aftercooler that cools compressed air to be supplied to the demand side at startup, each cooling pipe of the air discharge cooler and the aftercooler is provided in the same shell, and the cooling pipes of the aftercooler are provided in the shell. The header to be connected is divided into four chambers, and among these four chambers, a communication hole is provided between two adjacent chambers that communicate with each cooling pipe of the air cooler and aftercooler, and the above-mentioned check valve is inserted into this communication hole. At the same time, among the remaining two chambers of the four chambers, the other chamber communicating with the cooling pipe of the air discharge cooler is used as the air discharge pipe, and the other chamber communicating with the cooling pipe of the aftercooler is used as the demand side compression pipe. A compressor discharge piping system cooling device, characterized in that it is configured to be connected to an air piping. 2. In what is stated in claim 1,
The shell is arranged so that its longitudinal direction is horizontal, and each of the cooling pipes of the air cooler and the aftercooler in this shell is a U-shaped tube, and the upper part of the U-shaped tube is on the inlet side of the compressed air. . A discharge piping system cooling device for a compressor, characterized in that a lower part of the U-shaped pipe is communicated with an outlet side of compressed air. 3 In what is stated in claim 1,
A cooling device for a discharge piping system of a compressor, characterized in that the header has a hole in its outer wall that is larger than the outer diameter of the check valve part, and a cover is attached to the hole.