CN1321318C - A kind of online test method of refrigeration capacity of compressor - Google Patents

Abstract

An on-line testing method for the cooling capacity of a compressor and the steps for its establishment, which mainly determine the compressor (2) by measuring the value of the maximum limit pressure (P) of the plugging port of the compressor (2) within a limited period of time. Whether the cooling capacity (Q) is qualified or not is realized through the steps established by the equivalent relationship with the cooling capacity (Q) test scheme specified in the national standard, the purpose is to greatly simplify the batch compressor (2) cooling capacity ( Q) Test plan. The test device (R) used in this simple and convenient online test method for cooling capacity (Q) is mainly composed of: a pipe joint device (4), a rubber gas hose (5) with a certain volume, and a force Sensitive sensor (8) and the above-mentioned pressure and time numerical display part, this method can usually complete the online test of cooling capacity (Q) of different types of compressors (2) within a period of ten seconds to tens of seconds process.

Description

A kind of online test method of refrigeration capacity of compressor

Technical field:

The invention relates to a refrigeration compressor performance test scheme and a method for establishing an equivalent test relationship with national standard requirements.

Background technique:

For compressors used in refrigeration systems, an important test item specified in the national standard is: the cooling capacity test of the compressor, see section 4.2 of the national standard GB9098-88 (fully enclosed motor for refrigerators - compressor) . In short, according to the national standard: After connecting the tested compressor to a refrigeration system facility similar to a refrigerator (much more complicated than a refrigerator) for at least tens of minutes (usually more than half an hour) of refrigeration capacity testing, Only then can the final cooling capacity test results be obtained.

It can be seen that the facilities for testing the refrigerating capacity of the compressor are quite complicated, and the testing method is also very cumbersome and takes a long time. Therefore, the sampling test rate of the refrigeration capacity items of the mass-produced compressors is generally very low. Obviously, it is impossible to implement an online refrigeration capacity test for each compressor produced in batches, which has a great impact on the quality of the compressor products. Control is disadvantageous. ------The more important the test item is, the more each compressor should be tested, this is the best policy for quality control.

For this reason, how to greatly simplify the test method of the refrigeration capacity of the compressor, and realize the online test of its refrigeration capacity test item on the production line of the compressor product, that is: to conveniently realize the refrigeration of each compressor product on the production line It is a problem that relevant technical personnel have been deliberately trying to solve by performing online rapid testing within a period of tens of seconds to tens of seconds for quantitative items.

Among them, the key to solving the above-mentioned cooling capacity online test problem is: how to start from the compressor national standard cooling capacity test program, simplify it to a simple test program that can support its online test device, and how to compare the simple test program with the national standard cooling capacity test Schemes for establishing equivalence relationships.

Invention content:

Purpose of the present invention: just in order to solve above-mentioned two big key on-line testing problems closely related.

In order to realize the purpose of the invention, it is proposed to adopt the following technologies:

A. The test setup utilized includes:

a. The pipe joint device connected to the outlet pipe of the compressor under test; b. The force-sensitive sensor (including A/D conversion device) connected to the pipe joint device through the air pipe; c. Connected to the output end of the force-sensitive sensor The data display part consists of a pressure data display (displays the measured maximum limit pressure data of the plug) and a time data display (displays the time required to reach the above measured maximum limit pressure of the plug).

B. The two test data obtained and the conditions they meet respectively at the same time:

a. Measure the value of the maximum limit pressure of the blocked port of the tested compressor: when the maximum limit pressure of the blocked port is higher than the qualified pressure critical value, then: the cooling capacity of the tested compressor is qualified; when the maximum limit pressure of the blocked port is lower than When the pressure critical value is qualified, then: the refrigerating capacity of the compressor under test is unqualified; b. The value of the time required to measure the maximum ultimate pressure of the plug: when the required time is less than or equal to the critical time, then: The refrigerating capacity of the compressor under test is qualified, and when the required time is greater than the critical time, then: the refrigerating capacity of the compressor under test is unqualified.

C. The steps to obtain the pressure critical value, that is, the step to establish an equivalent relationship with the national standard cooling capacity critical value:

a. Take at least three compressors of the same model (including qualified products and unqualified products), and test their cooling capacity according to the national standard test cooling capacity requirements; b. Then connect the exhaust pipe of each compressor to the test The devices are connected, the suction pipe of the compressor is opened in the atmospheric space, start the machine and read their maximum limit pressure data from the pressure data display; c. According to "a" and "b" in item C At least three sets of quantitative data corresponding to the measured cooling capacity and the maximum ultimate pressure of the plugging are drawn, and their "Q (cooling capacity)-P (maximum ultimate pressure of the blocking)" rectangular coordinate relationship diagram is drawn, and the cooling capacity specified in the national standard For the critical value data, mark the coordinate position of the corresponding pressure critical value on the "Q (cooling capacity)-P (maximum ultimate pressure of plugging)" graph:

D. Steps to obtain the critical time:

a. Take a standard compressor prototype whose refrigerating capacity is exactly equal to the critical value of refrigerating capacity stipulated in the national standard, and measure the critical pressure value after connecting with the test device, and then get the T0 value; or: b. Use the above " C" is similar to the method of drawing the relationship diagram of "Q (refrigeration capacity)-P (maximum ultimate pressure of plugging)", draw the relationship diagram of "Q (refrigeration capacity)-T (required time to reach P)" or draw "P (maximum ultimate pressure of plugging) - T (required time to reach P)" relationship diagram, and obtain the critical time value from it.

The characteristics and significance of the present invention: the implementation plan of the cooling capacity test project required by the national standard can be equivalent through the present invention and a greatly simplified simple test plan is obtained, which greatly facilitates the use of refrigeration The most important refrigerating capacity test project of compressor products has created conditions for its online test. ——Greatly improved the quality control of compressor products in mass production.

Description of drawings:

Fig. 1 has schematically illustrated a kind of test embodiment of the present invention indirectly characterizing the refrigeration capacity of compressor by pressure value; Fig. 2 is the detailed diagram of K in Fig. 1; Fig. 3 has illustrated " Q ( Refrigeration capacity) - P (plug maximum ultimate pressure)" relationship diagram.

1: Suction pipe open in the atmospheric space (1 atmosphere) 2: Compressor under test; 3: Exhaust pipe; 4: Pipe joint device (composed of parts 9, 10 and 11); 5: Rubber gas transmission Hose; 6: Time (second) data display; 7: Pressure (atmospheric pressure) data display; 8: Force-sensitive sensor (including A/D conversion device); 9: Elastic clip device (similar to the elastic gas nozzle clip of a bicycle pump) structure); 10: sealing rubber ring; 11: air nozzle; R: the online cooling capacity test (actually pressure test) device of the present invention (composed of parts 4, 5, 6, 7 and 8); P: plugging The highest ultimate pressure; p ₀ : the critical pressure when the cooling capacity specified by the national standard is qualified; T: the time required to reach the above "P"; T ₀ : the critical time when the cooling capacity specified by the national standard is qualified; Q: refrigeration capacity; Q ₀ : the critical value of qualified cooling capacity stipulated in the national standard.

Detailed ways:

Fig. 1 schematically shows the device for online testing of cooling capacity Q of the present invention, and the compressor 2 under test works under the condition that the suction pipe 1 and the discharge pipe 3 are in a disconnected state, reflecting that the compression and discharge capacity of the compressor 2 under test is generally It consists of two aspects:

1. The maximum limit pressure P (in atmospheric pressure) of the compressor 2 in the open circuit working state is displayed by the pressure data display 7 . At this time, the data P also represents the high and low pressure compression ratio (closely related to the cooling capacity) of the compressor 2 (atmospheric pressure at the suction end is 1). When the P is greater than or equal to the critical pressure value _P0 , the refrigerating capacity Q of the tested compressor 2 is qualified, and when the P is less than the critical pressure _P0 , the refrigerating capacity Q of the tested compressor 2 is unqualified.

2. The required time T is displayed by the time data display 6 when the pressure P displayed by the pressure data display 7 reaches the highest value after starting the machine. When the T is less than or equal to the critical time T ₀ , then: the refrigerating capacity Q of the tested compressor 2 is qualified; when this T is greater than the critical time T ₀ , the refrigerating capacity Q of the tested compressor 2 is unqualified. The size of T is different for compressors 2 of different models. For example: under the premise that the internal volumes of the exhaust pipe 4 and the air hose 5 are fixed, when the compressor 2 of the general large exhaust power model is tested, the required T data is relatively small (the volume in the above-mentioned two pipes is very small. will soon be filled with the highest pressure gas); and when the compressor 2 of the general small exhaust power model is tested, the required T is too large (the volume inside the above-mentioned two tubes will not be filled with the highest pressure gas relatively quickly ), therefore, another major use of T is to help identify compressors 2 of different exhaust power (quantity) models.

Fig. 2 illustrates a problem about the feasibility that the present invention can realize on-line test: obviously, the pipe joint device 4 that is made up of elastic clip device 9, sealing rubber ring 10 and gas nozzle 11 can be completely by an operator, with a Only one hand can be used to connect or remove the gas nozzle 11 as conveniently as pumping gas to a bicycle. This creates conditions for completing the entire on-line test of the refrigeration capacity Q of the compressor 2 (actually a side test of the pressure P) within ten seconds.

Fig. 3 has shown the key of the present invention: by five compressors of the same model (three qualified and two unqualified) through national standard implementation scheme test refrigeration capacity Q, then test refrigeration capacity Q through the present invention test implementation scheme (actually After testing the pressure P), the relationship diagram of "refrigerating capacity Q-blocking maximum limit pressure P" is drawn. Wherein, the position of the critical pressure _P0 in the figure is obtained through the correspondence relation of the critical value _Q0 of the qualified cooling capacity of the compressor 2 for this type of refrigeration specified by the national standard.

Claims (3)

1. An online test method for the cooling capacity of a compressor, It is characterized by: A. The test setup (R) utilized includes: a. The pipe joint device (4) connected to the nozzle of the exhaust pipe (3) of the compressor under test (2); b. the force-sensitive sensor (8) that links to each other with pipe joint device (4) by gas delivery pipe (5); c. a data display part that is connected to the output end of the force sensitive sensor (8) and is composed of a pressure data display (7) and a time data display (6); B. The two test data obtained and the conditions they meet respectively at the same time: a. Measure the value of the maximum ultimate pressure (P) of the blocked port of the compressor (2) under test: When the maximum limit pressure (P) of the plugging port is higher than the qualified pressure critical value (P ₀ ), then: the cooling capacity (Q) of the compressor (2) to be tested is qualified; when the maximum limit pressure (P) of the plugging port is lower than the qualified When the pressure critical value (P ₀ ), then: the refrigerating capacity (Q) of the compressor (2) under test is unqualified; b. Take the value of the time (T) required to reach the maximum limit pressure (P) of the plugging port: When the required time (T) is less than or equal to the critical time (T ₀ ), then: the cooling capacity (Q) of the measured compressor (2) is qualified; when the required time (T) is greater than the critical time (T ₀ ), Then: the refrigerating capacity of the tested compressor (2) is unqualified. 2. an on-line testing method of compressor refrigerating capacity as claimed in claim 1, It is characterized in that it consists of the following steps for obtaining the critical pressure value (P ₀ ) and the steps for obtaining the critical time (T ₀ ): C. The step of obtaining the pressure critical value (P ₀ ), that is, the step of establishing an equivalent relationship with the national standard cooling capacity critical value (Q ₀ ): a. Take at least three compressors (2) of the same model, and test their cooling capacity (Q) according to the requirements of the national standard for testing cooling capacity; b. Then connect the exhaust pipe (3) of each compressor (2) to the test device (R), open the suction pipe (1) of the compressor (2) to the atmospheric space, start the machine and start the pressure Read their plugging maximum ultimate pressure (P) data in the data display (7); c. According to the quantitative data corresponding to at least three sets of cooling capacity (Q) and the maximum limit pressure (P) of the plugging port measured by "a" and "b" in item "C", draw their "refrigerating capacity ( Q)-Blocking maximum ultimate pressure (P)" Cartesian coordinate diagram, and according to the cooling capacity critical value (Q ₀ ) data stipulated in the national standard, in the "refrigeration capacity (Q) - blocking maximum ultimate pressure (P)" curve Mark the coordinate position of the corresponding pressure critical value (P ₀ ) on the graph; D. Steps to obtain the critical time (T ₀ ): a. Take a standard compressor (2) prototype whose refrigerating capacity (Q) is exactly equal to the critical value of refrigerating capacity (Q ₀ ) stipulated in the national standard, and measure its critical pressure value (P ₀ ) after connecting it to the test device (R). ) at the same time, the critical time (T ₀ ) value can be obtained; or: b. Use the method similar to that in the above item "C" to draw the relationship diagram of "refrigeration capacity (Q) - plugging maximum ultimate pressure (P)" to draw the relationship diagram of "refrigeration capacity (Q) - required time (T)" Or draw the relationship diagram of "maximum ultimate pressure of plugging (P) - required time (T)", and obtain the value of critical time (T ₀ ) from it. 3. An online testing method for compressor cooling capacity as claimed in claim 1, characterized in that: said at least three compressors (2) of the same type should include qualified products and unqualified products.

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