QC/T 661-2019Accumulators for automotive air conditioning (English PDF)

3.1 Accumulator

The accumulator is a device that separates refrigerant liquid and gas, ensures the outflow of refrigerant gas, has a refrigerator oil return flow compressor, filters the residual impurities of the refrigerant, adsorbs the residual moisture in the refrigeration system, stores the refrigerant.

4.2 Air tightness

After testing in accordance with 5.2, the total leakage rate of the refrigerant of the accumulator shall not be greater than 2 g/y, under the condition of 2.0 MPa detection pressure.

4.3 Pressure rupture resistance

After testing in accordance with 5.3, there shall be no leakage and obvious deformation under a pressure of 2.5 MPa; there shall be no rupture under a pressure of 3.5 MPa.

4.4 Vacuum resistance

After testing in accordance with 5.4, the pressure rise shall not exceed 0.5 kPa in 30 minutes.

4.5 Internal cleanliness

After testing in accordance with 5.5, the internal impurity content shall not be greater than 2.7 mg/dm2 (internal surface area); the size of solid particle impurities shall not be greater than 0.5 mm x 0.5 mm x 1.0 mm; the length of fiber impurities shall not be greater than 1.0 mm.

4.6 Drying performance

4.6.1 After testing according to 5.6.1, the water absorption capacity of the desiccant shall not be less than 15%.

4.6.2 After testing according to 5.6.2, the residual moisture of the desiccant shall not be greater than 2.0%.

4.7 Pressure loss

After testing in accordance with 5.7, the pressure difference between the inlet and outlet shall not be greater than 15 kPa.

4.8 Effective capacity

After calculation according to 5.8, the calculated value shall not be less than the value specified in the drawing.

4.9 Oil return capability

After testing according to 5.9, the mass of the compressor refrigeration oil remaining in the accumulator shall comply with the agreement between the supplier and the buyer.

4.10 Filtering capability

After testing according to 5.10, the size of impurity particles shall not be less than 200 µm.

4.11 Liquid-gas separation capability

After testing according to 5.11, the vapor content of the outlet refrigerant shall not be less than 85%.

4.12 High temperature resistance

After testing in accordance with 5.12, the appearance shall be free of abnormal deformation or damage; the air tightness shall meet the requirements of 4.1; the internal parts shall be free of damage.

4.13 Low temperature resistance

After testing in accordance with 5.13, the appearance shall be free of abnormal deformation or damage; the air tightness shall meet the requirements of 4.1; the internal parts shall be free of damage.

4.14 Resistance to temperature alternation

After testing in accordance with 5.14, the appearance shall be free of abnormal deformation or damage; the air tightness shall meet the requirements of 4.1; the internal parts shall be free of damage.

4.15 Vibration resistance

After testing in accordance with 5.15.1 and 5.15.2, the appearance shall be free of abnormal deformation or damage; the air tightness shall meet the requirements of 4.1; the internal parts shall be free of damage.

4.16 Resistance to pressure alternation

After testing in accordance with 5.16, the appearance shall be free of abnormal deformation or damage; the air tightness shall meet the requirements of 4.1; the internal parts shall be free of damage.

4.17 Corrosion resistance

After testing in accordance with 5.17, the air tightness and pressure resistance shall meet the requirements of 4.1 and 4.2.

5.1 Requirements for measuring instruments

5.1.1 The accuracy of the temperature measuring instrument shall not be less than ±0.2 °C.

5.1.2 The accuracy of the pressure measuring instrument shall not be less than ±1% of the absolute pressure reading.

5.1.3 The accuracy of the flow measuring instrument shall not be less than ±2% of the measured value.

5.1.4 The precision of the analytical balance shall not be less than 0.1 mg.

5.1.5 The precision of filter paper is not less than 5 µm.

5.1.6 The precision of the leak detector shall not be less than 1.0 x 10^-8 Pa·m3/s.

5.2 Air tightness test

Fill the accumulator with 2.0 MPa dry helium gas, at a purity of not less than 75%. Use a helium leak detector to make detection. The pressure holding time is not less than 15 seconds.

5.3 Pressure rupture test

Under protective conditions, the accumulator is filled with liquid medium, at a temperature of 23 °C ± 5 °C; the pressure increase rate is not greater than 0.1 MPa/s; the pressure is increased to 2.5 MPa; the pressure is held for 5 minutes. After inspection, if there is no leakage or obvious deformation, continue to increase the pressure to 3.5 MPa; hold the pressure for 3 min, it shall not rupture. Then increase the pressure until the product ruptures. Record the pressure value when the rupture begins.

5.4 Vacuum resistance test

Close one end of the inlet and outlet of the accumulator. Vacuum the other end. The internal pressure drops below 0.5 kPa. Stop vacuuming, after the exhaust pipeline in front of the vacuum pump is closed. The pressure rise change is not greater than 0.5 kPa in 30 minutes.

5.5 Internal cleanliness test

Weigh the filter paper, after placing it at a temperature of 90 °C ± 5 °C for no less than 30 minutes (mA). Pour analytical grade isooctane or ethanol solvent, that is about 30% of the volume of the accumulator, into the accumulator at room temperature.

5.16 Pressure alternation resistance test

Install the accumulator on the pressure alternating test bench. The hydraulic oil temperature is 80 °C ± 2 °C. The pressure is increased from 160 kPa to 1720 kPa; then reduced to 160 kPa, which forms one cycle. The frequency is 1.0 Hz ± 0.5 Hz. Continue for 150000 cycles.

5.17 Corrosion resistance test

Simulate the actual installation status of the accumulator on the vehicle. Conduct the SWAAT salt spray test, according to ASTM G85 A3, for 20 days or the time negotiated by the supplier and the buyer.

6.1 Exit-factory inspection

According to 4.2 exit-factory inspection, the sampling plan and acceptance quality level shall be determined, by negotiation between the supplier and the buyer.

6.2 Type inspection

6.2.1 When the accumulator falls into one of the following situations, type inspection shall be carried out:

a) During new product identification;

b) After mass production, if there are major changes in materials and process structures or changes in the production site, which may affect product performance;

c) After normal mass production, one year has passed since the last type inspection;

d) When the production is resumed after more than one year of suspension.

6.2.2 Type inspection covers all test items of this standard (or is conducted as required by agreement between the supplier and the buyer). Samples are randomly selected from qualified products; the number of samples for each test item is no less than 3. It is allowed to use the same sample to conduct tests on different items that do not affect the assessment. Please refer to Table 1, for type inspection items and requirements.