CN100425839C - Single-unit two-stage screw refrigeration compressor set and using method therefor - Google Patents

Abstract

The single machine dual screw compressor comprises a main motor (5) connecting with the machine through a coupler, air absorbing filter connecting with the machine's absorbing opening, exhaust of the middle cooling machine connecting with the high and low pressure joint pipe of the machine through middle filter, its exhaust connecting with the oil extractor, with a branch of the shell pass of the middle cooling machine connecting its tube pass, and the oil extractor connecting with the oil cooler. It can replace dual screw cooling compressor for low temperature cooling. It has eliminated a set of oil extractor, oil cooler, main motor with great reduction of cost. It is compact, with small land occupation and convenient for delivery and packing.

Description

Single-unit two-stage screw refrigeration compressor unit and its application method

technical field

The invention relates to a brand-new single-machine two-stage screw refrigeration compressor unit and an application method thereof, belonging to the technical field of refrigeration.

Background technique

The screw refrigeration compressor in the low-temperature refrigeration system operates under the condition of large pressure ratio and large pressure difference. Using a single-stage screw unit will greatly reduce the refrigeration efficiency and reduce the reliability of the compressor. Considering economy and reliability, a two-stage screw refrigeration system has appeared, which uses two screw refrigeration compressors as high and low pressure compressors respectively, and the refrigerant is compressed to an intermediate pressure through the low pressure compressor, and then combined with the The medium-temperature and medium-pressure refrigerant gas from the intercooler is mixed into the high-pressure machine for secondary compression. Due to the reduction of pressure ratio and pressure difference between high and low pressure compressors, the working conditions of the compressor are improved, and the unit cooling capacity is increased due to the supercooling of the high-pressure liquid from the condenser by the intercooler, which improves the refrigeration coefficient of the entire system. However, from the perspective of initial investment, it is obvious that the cost of two dual-stage units is higher than that of a single-stage unit, and the large size of the unit greatly restricts the application of the dual-stage system.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, and provide a brand-new single-machine two-stage screw refrigeration compressor unit and its application method. The technical problem to be solved is to not only bring into play the energy-saving advantages of the above-mentioned two-stage matching system, but also save costs to the greatest extent.

The technical solution adopted by the present invention to solve its technical problems is as follows:

A single-unit two-stage screw refrigeration compressor unit, including an oil pump, suction filter, coupling, main motor, oil separator, intercooler, oil cooler, console, oil filter and intermediate filter, single unit double One-stage screw refrigeration compressor; the two driving rotors of the high-pressure stage and low-pressure stage of the single-unit two-stage screw refrigeration compressor are connected by a built-in coupling. The high-pressure stage of a single-unit two-stage screw refrigeration compressor includes a high-pressure stage energy indicator, a high-pressure stage oil piston, and a high-pressure stage energy regulating slide valve connected in sequence, and also includes a high-pressure stage suction end seat, a high-pressure stage body, a high-pressure stage female rotor, A high-pressure male rotor and a high-pressure exhaust end seat, wherein the high-pressure female rotor and the high-pressure male rotor are installed in a high-pressure shell composed of a high-pressure suction end seat, a high-pressure body, and a high-pressure exhaust end seat; The low-pressure stage of a single-unit two-stage screw refrigeration compressor includes a low-pressure stage energy regulating slide valve, a low-pressure stage oil piston, and a low-pressure stage energy indicator connected in sequence, and also includes a low-pressure stage suction end seat, a low-pressure stage body, and a low-pressure stage female rotor. The low-pressure stage male rotor and the low-pressure stage exhaust end seat, wherein the low-pressure stage female rotor and the low-pressure stage male rotor are installed in the low-pressure stage shell composed of the suction end seat, the low-pressure stage body, and the low-pressure stage exhaust end seat.

The main motor is connected to the single-unit two-stage screw refrigeration compressor through a coupling, the suction filter is connected to the suction port of the single-unit two-stage compressor, and the outlet pipe of the intercooler is connected to the single-unit two-stage screw refrigeration compressor through the intermediate filter. The high and low pressure stage connecting pipes are connected, the exhaust port of the single-unit two-stage screw refrigeration compressor is connected with the oil separator, the shell side of the intercooler has a shunt connected with the tube side of the intercooler, and the oil separator is connected with the oil cooler connected.

The main motor inputs power to the single-unit two-stage screw refrigeration compressor through the coupling, and the low-temperature and low-pressure steam from the low-pressure system enters the low-pressure stage of the single-unit two-stage screw refrigeration compressor for compression after passing through the suction filter. The medium-temperature and medium-pressure gas from the machine is mixed and enters the high-pressure stage of the single-unit two-stage screw refrigeration compressor to be compressed again into high-temperature and high-pressure gas, enters the oil separator, and is discharged after oil-gas separation in the oil separator.

The high-pressure liquid from the liquid receiver enters the shell side of the intercooler, and leads out to the tube side of the intercooler after throttling and decompression. stage exhaust mixed; the remaining part enters the evaporator after supercooling; the refrigerating machine oil in the oil separator is cooled by the oil cooler and filtered by the oil filter, and part of it enters the single-machine two-stage screw refrigeration compressor under the action of pressure difference The low-pressure stage rotor cavity, the other part is pressurized by the oil pump and enters the rotor cavity of each stage through the compressor bearing, shaft seal and balance piston; the refrigerating machine oil in the rotor cavity is mixed with the inhaled steam and then is pumped by the single-machine two-stage screw refrigeration compressor The low pressure stage and high pressure stage are compressed and enter the oil separator for oil and gas separation.

Compared with the prior art, the present invention has the following positive effects: (1), each component is organically integrated into a unit through mutual connection, which makes the structure compact and occupies a small area, which is convenient for transportation and installation. (2) The single-unit two-stage screw refrigeration compressor is a whole composed of two compressors, and there is only one power input end, so the components of the unit are reduced by a set of oil separator and oil cooler compared with the conventional two-stage screw unit , motor, greatly reducing the cost. (3) Most of the components of the single-unit two-stage screw refrigeration compressor are borrowed from two single-stage screw refrigeration compressors. The components have a high degree of commonality, which is suitable for mass production and is also conducive to reducing design investment.

Description of drawings

Fig. 1 is a schematic structural diagram of a single-unit two-stage compressor unit of the present invention.

Fig. 2 is a schematic side view of the single-unit two-stage compressor unit of the present invention.

Fig. 3 is a view along the direction A of Fig. 2 .

Fig. 4 is a schematic structural diagram of a single-unit two-stage screw refrigeration compressor in the present invention.

FIG. 5 is a cross-sectional view along line A-A of FIG. 4 .

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings.

As shown in Figures 1, 2, and 3, the single-unit two-stage screw refrigeration compressor 1 and the main motor 5 are installed on the oil separator 7, the oil cooler 12 is installed on the side support of the oil separator 7, and the intercooler 11 is installed On the oil cooler 12 , a console 13 is mounted on the compressor mount of the oil separator 7 . All components form a single-unit two-stage screw refrigeration compressor unit according to the internal connection of the process. The drive rotors (male rotors) of the two separate high and low-pressure screw refrigeration compressors are connected to transmit power through the built-in coupling 24, making it a single-unit two-stage screw refrigeration compressor, and the power is input from the low-pressure stage male rotor.

The main motor 5 is connected to the single-unit two-stage screw refrigeration compressor 1 through the coupling 4, the suction filter 2 is connected to the suction port of the single-unit two-stage compressor 1, and the air outlet pipe of the intercooler 11 is connected to the The high and low pressure stage connecting pipes of the single-unit two-stage screw refrigeration compressor 1 are connected, the exhaust port of the single-unit two-stage screw refrigeration compressor 1 is connected with the oil separator 7, and the shell side of the intercooler 11 has a shunt connected with the intercooler. The pipe side is connected, and the oil separator 7 is connected with the oil cooler 12 .

The single-unit two-stage screw refrigeration compressor shown in Figure 4 and Figure 5 is the core component of this unit. Its main components are: high-pressure stage energy indicator 16, high-pressure stage oil piston 17, high-pressure stage suction end seat 18, high-pressure stage Energy adjustment slide valve 19, high-pressure stage body 20, high-pressure stage female rotor 21, high-pressure stage male rotor 22, and high-pressure stage exhaust end seat 23 form high-pressure stage. Low-pressure stage suction end seat 26, low-pressure stage body 27, low-pressure stage energy regulating slide valve 25, low-pressure stage female rotor 28, low-pressure stage male rotor 29, low-pressure stage exhaust end seat 30, low-pressure stage oil piston 31, low-pressure stage energy Indicator 32 constitutes the low pressure stage. The low-pressure stage male rotor 29 is connected to the high-pressure stage male rotor 22 through the built-in coupling 24 and transmits driving force thereto. The high-pressure stage female rotor 21 and the high-pressure stage male rotor 22 and the low-pressure stage female rotor 28 and the low-pressure stage male rotor 29 respectively mesh with each other, rotate according to a certain transmission ratio, and form working chambers with the high-pressure stage body 20 and the low-pressure stage body 27 respectively. High-pressure stage suction end seat 18, high-pressure stage exhaust end seat 23, high-pressure stage body 20, and low-pressure stage suction end seat 26, low-pressure stage exhaust end seat 30, and low-pressure stage body 27 are provided with suction and exhaust ports respectively. mouth and oil hole. The working process of the single-machine two-stage compressor is as follows: the low-temperature and low-pressure steam enters the low-pressure stage body 27 from the low-pressure stage suction end seat 26, and the working chamber composed of the low-pressure stage female rotor 28 and the low-pressure stage male rotor 29 is compressed to the intermediate pressure. It is discharged from the exhaust end seat 30 of the low-pressure stage, and then enters the suction end seat 18 of the high-pressure stage, and is compressed into a high-temperature and high-pressure gas through the working chamber composed of the high-pressure stage body 20, the high-pressure stage female rotor 21, and the high-pressure stage male rotor 22, and passes through the high-pressure stage. Stage exhaust end seat 23 is discharged. By controlling the entry and exit of lubricating oil on both sides of the high-pressure oil piston 17 and the low-pressure oil piston 31, the pressure on both sides of the oil piston is changed to drive the high-pressure energy adjustment slide valve 19 and the low-pressure energy adjustment slide valve 25 in their respective rotor chambers. Move, thereby changing the effective working length of the rotor, and realizing the energy stepless adjustment of the high and low pressure stage compressors. The high-pressure stage energy indicator 16 and the low-pressure stage energy indicator 32 respectively indicate the energy positions of the high and low-pressure stages.

The specific structure of the single-unit two-stage screw refrigeration compressor 1 is that the two drive rotors of its high-pressure stage and low-pressure stage are connected by a built-in coupling 24; wherein, the high-pressure stage includes a high-pressure stage energy indicator 16, a high-pressure stage Oil piston 17, high-pressure stage energy regulating slide valve 19 also include high-pressure stage suction end seat 18, high-pressure stage body 20, high-pressure stage female rotor 21, high-pressure stage male rotor 22 and high-pressure stage exhaust end seat 23, wherein, the high-pressure stage The stage female rotor 21 and the high-pressure stage male rotor 22 are installed in the high-pressure stage housing composed of the high-pressure stage suction end seat 18, the high-pressure stage body 20, and the high-pressure stage exhaust end seat 23; Spool valve 25, low-pressure stage oil piston 31, low-pressure stage energy indicator 32, also includes low-pressure stage suction end seat 26, low-pressure stage body 27, low-pressure stage female rotor 28, low-pressure stage male rotor 29, low-pressure stage exhaust end seat 30. Among them, the low-pressure stage female rotor 28 and the low-pressure stage male rotor 29 are installed in the low-pressure stage casing composed of the low-pressure stage suction end seat 26, the low-pressure stage body 27, and the low-pressure stage exhaust end seat 30.

The main motor 5 inputs power to the single-unit two-stage screw refrigeration compressor 1 through the coupling 4, and the low-temperature and low-pressure steam from the low-pressure system passes through the suction filter 2 and enters the low-pressure stage of the single-unit two-stage compressor 1 for compression. Mixed with the medium-temperature and medium-pressure gas from the intercooler 11, it enters the high-pressure stage of the single-unit two-stage screw refrigeration compressor 1 and compresses it again into high-temperature and high-pressure gas, enters the oil separator 7, and is discharged after oil-gas separation in the oil separator 7 .

The high-pressure liquid from the liquid receiver enters the shell side of the intercooler 11, and leads out to the tube side of the intercooler 11 after throttling and reducing pressure. The low-pressure stage exhaust in 1 is mixed; the remainder enters the evaporator after subcooling. The refrigerating machine oil in the oil separator 7 is cooled by the oil cooler 12 and filtered by the oil filter 8, and part of it enters the low-pressure stage rotor chamber of the single-unit two-stage compressor 1 under the action of the pressure difference, and the other part is pressurized by the oil pump 9 After that, it enters the rotor cavity of each stage through the compressor bearing, shaft seal and balance piston. The refrigerating machine oil in the rotor cavity is mixed with the inhaled steam, compressed by the low-pressure stage and high-pressure stage of the single-unit two-stage screw refrigeration compressor 1, and then enters the oil separator 7 for oil-gas separation, and then circulates sequentially. The effects of suction check valve 3, exhaust check valve 6, and middle check valve 15 are to prevent reverse rotation when the unit is shut down. The effect of the oil pressure regulating valve 10 is to play the effect of regulating the pressure after the oil pump 9 .

Claims (4)

1. A single-unit two-stage screw refrigeration compressor unit, including an oil pump (9), an air suction filter (2), a coupling (4), a main motor (5), an oil separator (7), an intercooler ( 11), oil cooler (12), console (13), oil filter (8) and intermediate filter (14), are characterized in that: also include single-unit two-stage screw refrigeration compressor (1); The two driving rotors of the high-pressure stage and the low-pressure stage of the screw refrigeration compressor (1) are connected through a built-in coupling (24); , high-pressure stage energy regulating slide valve (19), also includes high-pressure stage suction end seat (18), high-pressure stage body (20), high-pressure stage female rotor (21), high-pressure stage male rotor (22) and high-pressure stage exhaust End seat (23), wherein, the high-pressure stage female rotor (21), the high-pressure stage male rotor (22) are installed on the high-pressure stage suction end seat (18), the high-pressure stage body (20), the high-pressure stage exhaust end seat ( 23) in the high-pressure stage casing; the low-pressure stage includes the low-pressure stage energy regulating slide valve (25), the low-pressure stage oil piston (31), the low-pressure stage energy indicator (32), and the low-pressure stage suction end seat (26), low-pressure stage body (27), low-pressure stage female rotor (28), low-pressure stage male rotor (29), low-pressure stage exhaust end seat (30), wherein, low-pressure stage female rotor (28), low-pressure stage male rotor The rotor (29) is installed in the low-pressure stage casing formed by the low-pressure stage suction end seat (26), the low-pressure stage body (27), and the low-pressure stage exhaust end seat (30). 2. The single-unit two-stage screw refrigeration compressor unit according to claim 1, characterized in that: the main motor (5) is connected to the single-unit two-stage screw refrigeration compressor (1) through a coupling (4), and the suction filter (2) Connected to the suction port of the single-unit two-stage compressor (1), the outlet pipe of the intercooler (11) passes through the intermediate filter (14) and the high and low pressure stages of the single-unit two-stage screw refrigeration compressor (1) The connecting pipes are connected, the exhaust port of the single-unit two-stage screw refrigeration compressor (1) is connected to the oil separator (7), and the intercooler (11) has a shunt on the shell side that is connected to the tube side of the intercooler, and the oil separator (7) is connected with oil cooler (12). 3. The method of using the single-unit two-stage screw refrigeration compressor unit according to claim 1 or 2, characterized in that: the main motor (5) is input to the single-unit two-stage screw refrigeration compressor (1) through the coupling (4) Power, the low-temperature and low-pressure steam from the low-pressure system passes through the suction filter (2) and then enters the low-pressure stage of the single-unit two-stage screw refrigeration compressor (1) for compression, and is compressed with the medium-temperature and medium-pressure steam from the intercooler (11) After the gas is mixed, it enters the high-pressure stage of the single-unit two-stage screw refrigeration compressor (1), and is compressed again into high-temperature and high-pressure gas, which enters the oil separator (7), and is discharged after oil and gas separation in the oil separator (7). 4. The method of using the single-unit two-stage screw refrigeration compressor unit according to claim 3, characterized in that: the high-pressure liquid from the liquid receiver enters the shell side of the intercooler (11), and the lead-out path is throttled and depressurized. Enter the tube side of the intercooler (11), and after evaporation, filter through the intermediate filter (14) and mix with the low-pressure stage exhaust gas in the single-unit two-stage screw refrigeration compressor (1); the remaining part enters the evaporator after supercooling; The refrigerating machine oil in the oil separator (7) is cooled by the oil cooler (12) and filtered by the oil filter (8), and part of it enters the low-pressure stage of the single-unit two-stage screw refrigeration compressor (1) under the action of the pressure difference. The other part is pressurized by the oil pump (9) and then enters the rotor chambers at all levels through the compressor bearings, shaft seals and balance pistons; the refrigerating machine oil in the rotor chamber is mixed with the inhaled steam and is refrigerated and compressed by the two-stage screw of the single machine The low-pressure stage and high-pressure stage of the machine (1) are compressed and enter the oil separator (7) for oil-gas separation.

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