JPS62676A - Pulsation damper for reciprocating gas compressor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pulsation damper for a reciprocating gas compressor, particularly a π filter type pulsation damper.

[Prior Art] In the case of a reciprocating gas compressor, pulsations occur in the gas line due to the reciprocating motion of the piston. Pulsation in the gas line causes pipe vibration and must be prevented. A pulsation damper is used to reduce this gas pulsation.

Depending on the load, reciprocating gas compressors can be operated at 100% load, compressing gas in forward and backward motions, or at 50% load, compressing gas only in forward motion, depending on the load conditions. The generated pulsation components differ.

Therefore, the natural frequency of the pulsation damper is 100'
In case of X load, in case of 50% load (machine side vibration frequency is 10
It must also be able to cope with the situation (which is 1/2 compared to the case of 0%).

A π filter type pulsation damper is one example of a pulsation damper for preventing pulsation in a gas line of a reciprocating gas compressor.

A conventional π filter type pulsation damper (hereinafter referred to as π filter type damper) is shown in FIG.

The center of the tank 1 is partitioned by a partition wall 2, and the compartments 3 and 4 defined by the partition wall 2 are communicated with each other by a choke tube 5. Compressed gas flows into one compartment 3 and passes through the choke tube 5. It reaches the other compartment 4 and flows out from the other compartment 4. The compressed gas is pulsated by this process of inflow, passage through the choke tube 5, and outflow.

In this case, the vibration characteristics of the π filter type damper are as shown in FIG. 3, and have a natural frequency fh. Therefore, the specifications of the π filter type damper are determined so that the operating frequency f 2 satisfies f ≧2fhC.

By the way, the natural frequency f1 can be found using the following formula, where a
; Sound speed S: Choke tube cross-sectional area L: Choke tube length V: Tank volume.

[Problems to be Solved by the Invention] When trying to cope with the pulsations at 50% load and 100% load of a reciprocating gas compressor using the conventional π filter type damper described above, the operating frequency at 50% load As mentioned above, is 1/2 of the operating frequency at 100% load, so the specifications of the π film type damper must be such that it can suppress pulsation at 50% load.

Therefore, compared to the case where the specifications of the π filter type damper are determined so as to be effective for pulsation at 100% load, it is necessary to reduce the cross-sectional area of the choke duplex S so that the natural frequency becomes 1/2, or to reduce the cross-sectional area of the tube It is necessary to lengthen the length L or increase the tank volume V.

However, if the cross-sectional area S is made smaller, there is a problem that the pressure loss when passing through the choke tube at 100% load increases and the compressor performance deteriorates, so it is not possible to lengthen the choke tube L and increase the tank volume V. There is a problem that production costs increase.

[Means for Solving the Problems] The present invention is intended to solve the above-mentioned problems, and divides the inside of the tank into partitions 2 by partition walls, and connects both compartments with a renovated choke duplex, so that the required choke The tube is equipped with an on-off valve.

[For use] The choke tube on-off valve is closed as appropriate, the total cross-sectional area of the choke tube and the length of the choke tube are changed, and the natural frequency of the pulsation damper is changed depending on the load condition of the compressor.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a first embodiment, in which 6 represents a π filter type damper and 12 represents a compressor.

Is tank 1 a bulkhead? It is divided into 2 separate rooms 3 and 4 by
Communication is provided by a large-diameter choke tube 8 and a small-diameter choke tube 9 of the same length. Each of the choke tubes 9 and 10 has a midway portion exposed to the outside of the tank, and diaphragm type on-off valves 10 and 11 are provided in this exposed portion.

The branch chamber 4 and the compressor 12 are connected by a conduit 13. The compressor 12 is equipped with a suction valve 16.17 that is opened and closed by a pneumatic unloader 14-15, and a discharge valve 18.19 that communicates with the discharge pipe 25.
The cooperation between the discharge valves 18 and 19 and the piston 20 compresses the gas and delivers it to the compartment 3.

The on-off valve 10 and the unloader 14 are connected by a pneumatic actuation line 21, and the on-off valve 11 and the unloader 15 are connected by a pneumatic actuation line 22, and each actuation line 2L22 receives a capacity adjustment signal a.

It is equipped with solenoid valves 23, 24 driven by b.

The cross-sectional area S i of the choke tubes 8 and 9.

From equation (1) above, S2 has a natural frequency of fh100%=
It is determined that 4S+ = 32 so that 2 fR is 50%.

When the compressor 12 is operated at 100% load, the on-off valve 11 is opened by operating the solenoid valve 24, and the solenoid valve 2 is opened.
The on-off valve 10 is opened by the operation in step 3. In this state 1
00% load operating frequency f. is twice as large as the unique dynamic fa, and it functions as a damper.

The suction valves 16 and 17 are connected to the unloader 14 by solenoid valves 23 and 24 so as to be opened and closed in response to the movement of the piston 20.
, 15 are driven.

Next, when operating the compressor 12 at 50% load, the on-off valve 11 is opened by operating the solenoid valves 23 and 24, and the on-off valve 10 is opened.
is closed. In this state, compared to the case of 100% load,
Driving motion frequency f. is 1/2, so it still effectively functions as a damper.

Note that during 50% load operation, the suction valve 16 is open all the time.

FIG. 2 shows a second embodiment, in which choke tubes 8 and 9 have the same length but different cross-sectional areas, and on-off valves 10 and 11 are provided at the end faces of the choke tubes 8 and 9. .

In this embodiment as well, 50% load and 100% load can be handled by selectively opening and closing the on-off valves 10 and 11.

Furthermore, various embodiments of the present invention have been prepared, and the choke tubes 8 and 9 shown in FIG. , at 100% load, both may be fully opened and the cross-sectional area may be set such that the required performance is achieved.

Furthermore, the lengths of the two choke tubes may be different while maintaining the same cross-sectional area.

Also, both the choke tube length and cross-sectional area may be varied.

Furthermore, there may be three or more choke tubes.

[Effects of the Invention] As described above, according to the present invention, the tank volume can be increased by 100% with a simple mechanism without increasing the pressure loss.
Pulsation during load operation and pulsation during 50% load operation can be suppressed.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of a first embodiment of the present invention, FIG. 2 is a schematic explanatory diagram of a second embodiment of the same, and FIG. 3 is an explanatory diagram of a conventional example. 1 is a tank, 2 is a partition wall, 3 and 4 are 9 to 9, 8 and 9 are choke tubes, and 10.11 is an on-off valve.

Claims (1)

[Claims] 1) A pulsation reciprocating gas compressor characterized in that the interior of the tank is partitioned into a partition 2, the two partitions are communicated through a plurality of choke tubes, and the required choke tubes are provided with on-off valves. damper.