SH/T 0103-2007 Determination of shear stability of polymer-containing oils — Diesel injector nozzle method

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Card type: Test method

1. Method number / full title / English title / supersession relationship

• Standard number: SH/T 0103-2007
• Chinese title: Determination of shear stability of polymer-containing oils — Diesel injector nozzle method
• English title: Standard test method for shear stability of polymer containing fluids using a European diesel injector apparatus
• Supersession relationship: supersedes SH/T 0103-1992 "Determination method for shear stability of polymer-containing oils (diesel injector nozzle method)"
• Adoption relationship: modified adoption of ASTM D6278-02 "Standard test method for shear stability of polymer-containing oils (European diesel injector nozzle equipment method)"
• Publication/implementation: published by 2007-08-01, implemented by 2008-01-01
• Responsible/ proposing body: proposed by China Petrochemical Corporation; administered by the Petrochemical Research Institute of China Petroleum & Chemical Corporation
• Drafting organizations: Dalian Lubricant Research and Development Center of PetroChina Company Limited; Petrochemical Research Institute of China Petroleum & Chemical Corporation
• Main drafters: Liu Xingye, Li Yunpeng, Yao Qifeng, Liu Honghui
• Previous versions: SH/T 0103-1992

2. Scope of application and non-applicability

• 1.1 specifies a method for determining the shear stability of polymer-containing oils, using a European diesel injector nozzle tester to determine the kinematic viscosity loss of polymer-containing oils at 100℃. The viscosity loss reflects the degree of degradation of the polymer under the shearing action of the nozzle.
• 1.2 involves certain hazardous materials, operations and equipment, but it is not intended to address all safety issues associated with them; users should establish appropriate safety and protective measures before use and determine applicable management systems.
• 5.3 This method cannot predict the viscosity loss produced under different equipment and different conditions of actual use; only when polymer degradation in actual use is mainly caused by mechanical shearing does the test result have a certain correlation with actual use.
• Not applicable: no other explicit statement of non-applicability is provided in the available source.

3. Method principle

• 4 Method summary: when a polymer-containing oil passes through a diesel injector nozzle at a certain shear rate, degradation of the polymer molecules is caused; the degradation leads to a decrease in the kinematic viscosity of the test sample, and the percentage viscosity loss is used to express the mechanical shear stability of the polymer-containing oil.
• 5.1 This method evaluates the percentage viscosity loss of polymer-containing oils caused by polymer degradation in a high-shear nozzle apparatus; the effects of heat and oxidation on the test are very small.

4. Reagents and materials (purity / preparation)

• 7.1 Diesel engine fuel injection pump calibration oil: meets the requirements of GB/T 8029, used to adjust the opening pressure of the diesel injector nozzle valve system.
• 7.2 Reference oil: RL-34, used to ensure that when the instrument is adjusted within the specified pressure range, the viscosity loss value is within the specified range.
• 10.6.19 Note: suitable break-in oils include fully formulated 15W-40 heavy-duty engine oil.
• Other purity and preparation requirements: not provided in the available source.

5. Apparatus and equipment

• 6.1 Diesel injector nozzle shear stability tester: see Figures A.1 to A.3 in Annex A; it consists of a reservoir, a dual-piston pump with an electric drive, an atomization chamber with a diesel injector nozzle, and a liquid cooling device; the ambient temperature of the installation area is 20℃ to 25℃. The equipment outline is described in Figure A.1.
• 6.1.1 Reservoir: as shown in 7 of Figure A.1, open at the top, with a volume of about 250 mL, an inner diameter of 42 mm, and calibrated in volume units. The reservoir is installed together with an internal distribution plate (4 in Figure A.1). A watch glass with a serrated edge of diameter 40 mm is used as the standard distribution plate to help make the circulating oil sample form turbulent flow. The temperature is measured with a thermometer suspended in the center of the reservoir; the bottom of the thermometer should be installed at 10 mm to 15 mm above the oil outlet (requires confirmation against the source standard (source-text extraction): the source text reads "large 19mm~15mm"); other temperature measuring devices may also be used. At the oil outlet, a connecting piston with a conical outer diameter and an orifice diameter of 8 mm is installed (8 in Figure A.1). The plastic tube connected to the pump suction inlet (10 in Figure A.1) is used to connect the connecting piston at the reservoir outlet and the pump inlet.
• 6.1.2 Piston injection pump (11 in Figure A.1): model Bosch PE 2-A-9QD-300/3 S2266 (requires confirmation against the source standard (source-text extraction)); this pump is installed together with a stroke counter (15 in Figure A.1), a pump vent screw (14 in Figure A.1), and a pump flow rate adjusting screw (12 in Figure A.1).
• 6.1.3 Injection pump (13 in Figure A.1): driven by a three-phase motor, at a speed of 925 r/min ±25 r/min.
• 6.1.4 Injection pump outlet: connected to the atomization chamber by a high-pressure-resistant steel pipe. To reduce the formation of bubbles, the atomization chamber (2 in Figure A.1, with detailed illustration in Figure A.2) is designed so that the sample fills the chamber from the nozzle during the test. A drain pipe equipped with a switch (3 in Figure A.1) is used to reduce contamination from the previous test during cleaning of the system. The diesel injector nozzle used is a Bosch DN 8 SP type pintle injector, batch number 0434 200 012, installed on a Bosch KD 43 SA 53/13 or Bosch KD 43 SA 53/15 type nozzle holder; the nozzle holder includes a filter cartridge.
  • Note: ASTM D6278-02 requires nozzle holder model Bosch KD 43 SA 53/15; considering that DIN 51382 and CEC L-14-A-93 still require the use of Bosch KD 43 SA 53/13 type holders, and that instruments in use in China basically also use Bosch KD 43 SA 53/13 type holders, this standard specifies that both types of holders may be used.
  • Note: to avoid damage to precision components of the fuel injection device (such as pins and sleeves in the pump and nozzle valve assembly), maintenance work on the equipment should be carried out by experts in the field of diesel injection pumps or with reference to the factory service manual.
  • Note: if the filter cartridge becomes clogged during the test, it will cause an abnormal increase in the pressure gauge reading; when this occurs, the filter cartridge should be replaced.
• 6.1.5 Pressure sensing device (18 in Figure A.1): it may be a glycerin-filled pressure gauge or an electrically controlled, digital pressure display; it should be separated from the pipeline by installing a pressure buffer or needle valve so as to appropriately eliminate pressure fluctuations. The pressure device should be pressure-tested periodically to ensure its accuracy.
• 6.1.6 Cooler (5 in Figure A.1): used to maintain the specified temperature of the test sample (at the reservoir outlet). The cooler is a glass vessel with an external cooling jacket structure, and the heat transfer surface is spherical. The outer diameter of the cooler is about 50 mm, the diameter of the heat transfer surface is about 25 mm, and the length of the cooler is about 80 mm. The position of the oil distribution plate in the reservoir should be above the cooler to ensure sufficient contact between the sample and the cooling surface. The cooler discharges the sample through a three-way stopcock (6 in Figure A.1, the same as the three-way stopcock on the reservoir). In addition, the cooler should be installed together with a device capable of adjusting flow rate.
• Annex A (normative annex) Diesel injector nozzle shear stability tester, Figures A.1 to A.3.

6. Recommended operating conditions

• Ambient temperature: 20℃ to 25℃ (6.1, 10.6.1).
• Sample temperature: measured at the reservoir oil outlet, maintained between 30℃ and 35℃ (10.6.11, 11.2.9).
• Pump speed: 925 r/min ±25 r/min (6.1.3).
• Flow rate: 170 mL/min (10.6.8).
• Pump operating time: 60 s ±1 s (10.3.13).
• Calibration pressure range: 13.0 MPa to 18.0 MPa (3.2, 10.6.17, 10.6.18).
• Nozzle opening pressure: new or uncalibrated nozzles are adjusted to 13.0 MPa (10.1.1); calibrated nozzles are adjusted to the pre-calibrated pressure, but it must be between 13.0 MPa and 18.0 MPa (10.1.1).
• Preheating: before calibration with RL-34 reference oil, a preheating operation of 30 min is required; set the stroke counter to shut off the machine at 30n strokes, then start the pump; the preheating process is required only for the first calibration of the day (10.4).
• Calibration interval: calibration should be performed on the same day as the test sample and before testing the test sample; after 420 cycles of testing or calibration, or after seven days, the instrument must be recalibrated with RL-34 reference oil (10.7).
• Number of test strokes: 230n (11.2.5).
• Other conditions: not provided in the available source.

7. Sampling and sample preparation

• 9.1 Each test requires approximately 2600 mL of sample (requires confirmation against the source standard (source-text extraction): the source text reads "2600mL.").
• 9.2 Before the sample is added to the test apparatus, it should be uniform in appearance at room temperature and free of any visible insoluble matter.
• 9.3 Before the test, water and insoluble matter should be removed from the sample; otherwise, clogging of the filter cartridge and damage to the nozzle may occur; clogging of the filter cartridge can be observed through an instantaneous increase in pressure, and insoluble matter entering the shear zone will shorten the service life of the nozzle.
• Other sampling and preparation: not provided in the available source.

8. Analytical procedure

• 10 Calibration
  • 10.1 Adjust the nozzle
    • 10.1.1 If a new or uncalibrated nozzle is used, the positions of the nozzle holder and nozzle should be appropriately adjusted. Use diesel engine fuel injection pump calibration oil and a nozzle tester to adjust the nozzle, ultimately making the nozzle opening pressure 13.0 MPa. If the nozzle has already been calibrated with RL-34 reference oil, adjust the nozzle opening pressure to the pre-calibrated pressure, but it must be between 13.0 MPa～18.0 MPa.
    • 10.1.2 Install the nozzle and nozzle holder on the test apparatus; the nozzle should be tightly mounted on the atomization chamber to prevent leakage of the sample around the outer surface of the nozzle.
  • 10.2 Measure the residual dead volume (Ves)
    • 10.2.1 The volume of sample remaining in the system that cannot be discharged refers to the volume between the three-way stopcock at the outlet of the liquid storage tank and the nozzle orifice (1 in Figure A.1). If the dead volume is known, proceed according to clause 10.3. The dead volume does not include the volume of the atomization chamber.
    • 10.2.2 When measuring the residual dead volume, start the pump and drain the sample from the previous test.
    • 10.2.3 Remove the high-pressure line and drain the sample; remove the piston at the end of the pump circuit and discharge the sample remaining in the pump; open the atomization chamber and discharge the sample therein.
    • 10.2.4 Reassemble the system and close all oil outlets. The three-way stopcock at the coolant outlet should be connected to the liquid storage tank below it, and the three-way stopcock at the outlet of the liquid storage tank should be connected to the pipe connected to the pump suction inlet.
    • 10.2.5 Add 170 mL RL-34 reference oil to the liquid storage tank and observe the liquid level. Start the pump and run for a few minutes until the sample is completely detached and there are no suspended bubbles.
    • 10.2.6 Drain the sample in the atomization chamber into a beaker, then pour it back into the liquid storage tank below. Loss of the drained sample will cause errors in the calculation of Ves. Allow the system to drain sample 20 mL, and remove air from the connecting pipe between the liquid storage tank and the pump.
    • 10.2.7 Observe the change in liquid level in the liquid storage tank and compare it with the liquid level recorded in 10.2.5. Calculate the change in residual volume, which is Ves.
      • Note: Tests have shown that the dead volume is approximately 15 mL～30 mL. When the sample in the atomization chamber is not drained back to the liquid storage tank or the pipe connected to the pump suction inlet is too long, the measured dead volume may exceed this range.
    • 10.2.8 Calculate the test sample volume Vn as the difference between 170 mL and Ves.
  • 10.3 Clean the apparatus, set the instrument, and adjust the pump stroke
    • 10.3.1 Drain the residual sample from the previous test through the oil drain pipe, and drain the sample from the cooler and the liquid storage tank through the two three-way stopcocks into suitable containers.
    • 10.3.2 After the sample is completely drained, keep the switch on the oil drain pipe of the atomization chamber open, adjust the three-way stopcock at the cooler outlet to drain the residual sample in the cooler into the waste oil cup. Adjust the three-way stopcock at the outlet of the liquid storage tank to close the oil drain pipe, but it should be opened toward the pump suction direction through the connecting pipe between the liquid storage tank and the pump. Add 50 mL RL-34 reference oil to the liquid storage tank.
      • Note: 10.3.2～10.3.7 are two separate cleanings of the instrument with 50 mL sample to remove residual sample from the previous calibration or test. In the above steps, the atomization chamber switch and the three-way stopcock at the cooler outlet should be opened toward the direction of flow to the waste oil cup.
    • 10.3.3 Remove air from the line by adjusting the pump vent screw and manually compressing the pipe connected to the pump suction inlet.
    • 10.3.4 Set the stroke counter so that the pump has enough time to discharge the sample from the liquid storage tank.
    • 10.3.5 Start the pump and observe the liquid level change in the liquid storage tank. When the sample in the liquid storage tank is completely drained but the pipe connected to the pump suction inlet is still full of sample, stop the pump.
    • 10.3.6 Add at least 50 mL RL-34 reference oil to the liquid storage tank for the second time, start the pump until the sample in the liquid storage tank is completely drained while the pipe connected to the pump suction inlet is still full of sample, then stop the pump.
    • 10.3.7 After the sample is completely drained, close the atomization chamber switch, and adjust the three-way stopcock at the cooler outlet so that the sample flows through the cooler and enters the liquid storage tank.
    • 10.3.8 Remove the thermometer or temperature sensor from the liquid storage tank.
      • Note: The thermometer and related components will affect the accurate measurement of the liquid storage tank volume, so when accurate measurement of the sample volume is required, they should be removed. A thermocouple or temperature sensor may also be used instead of a thermometer.
    • 10.3.9 Add at least Vn + 30 mL of RL-34 reference oil to the liquid storage tank.
    • 10.3.10 Close the atomization chamber switch, and adjust the three-way stopcock at the cooler outlet so that the sample flows through the cooler and enters the liquid storage tank.
      • Note: During the third cleaning and subsequent test procedures, the oil drain pipe switch of the atomization chamber should always be kept closed.
    • 10.3.11 Remove air from the apparatus by manually compressing the pipe connected to the pump suction inlet or adjusting the pump vent screw.
    • 10.3.12 Record the reading of the stroke counter.
    • 10.3.13 Use a stopwatch or other timing device to time; the pump operating time is 60 s ±1 s.
    • 10.3.14 Measure the number of strokes per minute n, the difference between the stroke counter reading after the pump has run 60 s ±1 s and the reading recorded in 10.3.12.
    • 10.3.15 Set the stroke counter to stop at 3n, that is, the pump should run 3 min. Use a timing device to observe the stroke counter to determine whether the value of n is correct. Start the pump and let the sample circulate until the set value of the stroke counter.
    • 10.3.16 After the sample is completely drained, adjust the sample volume in the liquid storage tank to determine that the sample volume is the same as Vn.
    • 10.3.17 Set the stroke counter to 0.5n.
    • 10.3.18 Adjust the three-way stopcock at the cooler outlet so that after the pump starts, the sample can be stored in the cooler.
    • 10.3.19 Start the pump. When the pump stops and the sample is completely drained, subtract the sample volume then in the liquid storage tank from Vn.
    • 10.3.20 If the difference is within the range of 1/2Vtot ±2.5 mL (Vtot = Vn + Ves), proceed to clause 10.4.
    • 10.3.21 If the difference between the sample volume in the liquid storage tank and Vn is not within the range of 1/2Vtot ±2.5 mL, drain the sample in the cooler into the oil storage tank, adjust the pump stroke via the pump flow rate adjusting screw, and repeat the above steps starting from 10.3.16.
  • 10.4 Preheating: Before calibration with RL-34 reference oil, a preheating operation of 30 min is required. Set the stroke counter to shut down the machine at 30n strokes, then start the pump. Note: The preheating process is only required for the first calibration of the day.
  • 10.5 Drain residual sample: Open the atomization chamber switch to drain the sample from the previous test, adjust the three-way stopcock at the outlet of the liquid storage tank so that all the sample in the liquid storage tank is drained into the waste oil cup. After the sample is completely drained, adjust the three-way stopcock to close the oil outlet and position the opening toward the pump suction inlet.
  • 10.6 Calibrate with RL-34 reference oil
    • 10.6.1 Confirm that the ambient temperature (room temperature) is between 20℃～25℃.
    • 10.6.2 Add at least 50 mL RL-34 reference oil to the liquid storage tank. Adjust the three-way stopcock at the cooler outlet so that the sample flows through the cooler into the waste oil cup, and open the atomization chamber switch. Start the pump until the sample in the liquid storage tank is completely drained but the pipe connected to the pump suction inlet is still full of sample.
    • 10.6.3 Remove air from the line by manually compressing the connecting pipe between the pump and the liquid storage tank. If necessary, the pump vent screw may also be adjusted.
    • 10.6.4 Add at least 50 mL RL-34 reference oil to the liquid storage tank again, start the pump until the sample in the liquid storage tank is completely drained but the pipe connected to the pump suction inlet is still full of sample.
    • 10.6.5 Close the atomization chamber switch, adjust the three-way stopcock at the outlet of the liquid storage tank so that the opening is connected toward the pump suction inlet, and maintain the position of the three-way stopcock at the cooler outlet so that the next first 50 mL RL-34 reference oil can be drained into the waste oil cup.
    • 10.6.6 Add at least Vn + 30 mL of RL-34 reference oil to the liquid storage tank.
    • 10.6.7 Start the pump. When the sample liquid level in the liquid storage tank drops by 50 mL, stop the pump. After the sample is completely drained, readjust the three-way stopcock at the cooler outlet so that the subsequent sample can flow directly into the liquid storage tank.
    • 10.6.8 Set the stroke counter to automatically shut off the pump at 30n. The flow rate is 170 mL/min.
    • 10.6.9 If necessary, adjust the sample volume in the liquid storage tank to Vn.
    • 10.6.10 Place the temperature measuring device into the liquid storage tank, then start the pump.
    • 10.6.11 After 10 min, adjust the flow rate of the cooling water to keep the sample temperature between 30℃～35℃, with the temperature measured at the oil outlet of the liquid storage tank. Approximately 10 min of test time is required before the temperature stabilizes.
    • 10.6.12 After approximately 10 test cycles, record the pressure gauge reading; read the glycerin pressure gauge to 0.1 MPa, and the electronic pressure measuring device to 0.01 MPa.
      • 10.6.12.1 The pressure measuring device must be periodically subjected to pressure measurement to ensure its accuracy.
    • 10.6.13 After 30 cycles, the pump stops; open the atomization chamber switch and let the sample flow into the waste oil cup. Open the three-way stopcock at the outlet of the liquid storage tank, drain the initial 10 mL～15 mL sample to flush the oil outlet pipe, then collect the remaining sample into the sample cup. After the sample is completely drained, close the three-way stopcock.
    • 10.6.14 Remove the thermometer or temperature sensor probe.
    • 10.6.15 Use the method of GB/T 265 to measure the kinematic viscosity of RL-34 reference oil at 100℃ before shearing, and simultaneously measure the kinematic viscosity of RL-34 reference oil at 100℃ after shearing in clause 10.6.13. The same viscometer should be used when measuring kinematic viscosity.
    • 10.6.16 Calculate the viscosity loss value V (mm²/s) using formula (1): V = V1 - V2 (1). Where: V1— kinematic viscosity of the sample before shearing at 100℃, mm²/s; V2— kinematic viscosity of the sample after shearing at 100℃, mm²/s.
    • 10.6.17 The V of the RL-34 reference oil should be between 2.75 mm²/s and 2.85 mm²/s (after the test with 10 min, the pressure gauge reading should be between 13.0 MPa and 18.0 MPa). After obtaining a qualified test result, take the pressure recorded in 10.6.12 as the calibration pressure for the test.
    • 10.6.18 When the pressure gauge reading recorded in 10.6.12 is between 13.0 MPa and 18.0 MPa, if V is less than 2.75 mm²/s, increase the pressure gauge pressure; if V is greater than 2.85 mm²/s, decrease the pressure gauge pressure. When adjusting the pressure, first open the dust cover of the nozzle holder, loosen the lock nut, and turn the adjusting screw to adjust the valve system opening pressure. Then tighten the lock nut and install the dust cover. The nozzle and nozzle holder do not need to be removed from the apparatus. Continue testing the RL-34 reference oil until the calibration result is qualified.
      • Note: During the entire process, the dust cover must be tightened. If it is not tightened, oil leakage may occur around the outside of the nozzle apparatus, which will reduce some of the mechanical shearing process of the oil sample and thereby significantly affect the precision of the test. This situation can be monitored by a pressure recorder or electronic pressure measuring device, because if oil leakage occurs, the pressure will drop significantly when the sample passes through the nozzle.
    • 10.6.19 When V is greater than 2.85 mm²/s, and the pressure is only 13.0 MPa, a fully formulated engine oil may be used as a break-in oil to break in the nozzle. The stroke counter may be adjusted to the minimum test time of 8 h instead of 30 min. Then test again with the RL-34 reference oil, starting from clause 10.5. Continue the pretreatment and measure the new nozzle until the calibration requirements in 10.6.17 are met.
      • Note: Suitable break-in oils include fully formulated 15W-40 heavy-duty engine oil.
    • 10.6.20 When V is less than 2.75 mm²/s, and the pressure has reached 18.0 MPa, the nozzle should be replaced and the calibration procedure should be carried out again.
      • Note: Before calibrating a new nozzle, it is recommended to first break it in with break-in oil for at least 4 h.
  • 10.7 Calibration interval: Calibration should be performed on the same day as the sample to be tested and before testing the sample to be tested. After the instrument has undergone 420 cycles of testing or seven days after calibration, it must be recalibrated with RL-34 reference oil.
• 11 Test procedure
  • 11.1 Adjust the sample flow rate: Turn on the atomization chamber switch and drain the sample from the previous test. Adjust the three-way stopcock at the cooler outlet so that the sample drains into a suitable waste oil cup. Then adjust the three-way stopcock at the liquid storage tank outlet, close the drain pipe, and connect the pipe connected to the pump suction inlet.
    • 11.1.1 Add at least 50 mL of sample.
    • 11.1.2 Manually drain the air from the connecting pipe and the hose connected to the pump suction inlet. If necessary, the pump vent screw may also be adjusted.
    • 11.1.3 Start the pump until the sample in the liquid storage tank is drained, but the pipe connected to the pump suction inlet remains filled with sample.
    • 11.1.4 Add at least 50 mL of sample again to the liquid storage tank, start the pump until the sample in the liquid storage tank is drained again, but the pipe connected to the pump suction inlet remains filled with sample.
    • 11.1.5 When the sample is completely drained, turn off the atomization chamber switch and adjust the three-way stopcock at the cooler outlet so that the sample can flow through the cooler and enter the liquid storage tank.
    • 11.1.6 Add Vn + 30 mL of sample to the liquid storage tank.
    • 11.1.7 Adjust the pump vent screw and manually compress the pipe connected to the pump suction inlet to drain the air from the pipeline.
    • 11.1.8 Set the stroke counter to 3n, start the pump, and let the sample circulate until the stroke counter automatically shuts down the machine.
    • 11.1.9 Adjust the liquid level in the liquid storage tank to Vn by draining excess sample or adding sample (if necessary).
    • 11.1.10 Set the stroke counter to 0.5n.
    • 11.1.11 Adjust the three-way stopcock at the cooler outlet so that the sample can be stored in the cooler after the pump is started.
    • 11.1.12 Start the pump; when the pump stops, subtract the sample volume then in the liquid storage tank from Vn.
    • 11.1.13 When the difference is within the range of 1/2Vtot ±2.5 mL, proceed to clause 11.2.
    • 11.1.14 If the difference between the sample volume in the liquid storage tank and Vn is not within 1/2Vtot ±2.5 mL, adjust the pump stroke using the pump flow rate adjusting screw, drain the sample in the cooler into the liquid storage tank, and restart the test from 11.1.6.
  • 11.2 Drain the sample: Keep the atomization chamber switch in the off state. Drain the sample in the cooler into the waste oil cup, then reset the three-way stopcock at the cooler outlet so that the sample can flow into the liquid storage tank. Then adjust the three-way stopcock at the liquid storage tank outlet to drain the sample into the waste oil cup, and readjust the three-way stopcock at the liquid storage tank outlet so that the opening direction faces the pump suction inlet pipeline.
    • 11.2.1 Keep the atomization chamber switch in the off state. Reset the three-way stopcock at the cooler outlet so that the first 50 mL of sample can be drained into the waste oil cup.
    • 11.2.2 Add at least Vn + 30 mL of sample to the liquid storage tank.
    • 11.2.3 Manually compress the pipe connected to the pump suction inlet to drain the air in the apparatus. If necessary, the pump vent screw may also be adjusted.
    • 11.2.4 Start the pump; when the liquid level in the liquid storage tank drops by 50 mL, turn off the pump. When the sample is drained, readjust the three-way stopcock at the cooler outlet so that the subsequent sample can flow directly into the liquid storage tank.
    • 11.2.5 Set the stroke counter to automatically shut down the machine at the required number of strokes (230n).
    • 11.2.6 Adjust the volume of the sample in the liquid storage tank to Vn.
    • 11.2.7 Place a thermometer or temperature sensor into the liquid storage tank.
    • 11.2.8 Start the pump.
    • 11.2.9 Adjust the cooling water flow rate to control the temperature of the sample at the liquid storage tank oil outlet between 30℃ and 35℃. Note: At this time there is no pressure display, because the displayed pressure may differ from the pressure value recorded in the previous calibration.
    • 11.2.10 After the test has gone through 30 cycles and the pump stops, turn on the atomization chamber switch and drain the sample into the waste oil cup; adjust the three-way stopcock at the liquid storage tank outlet to drain the initial 10 mL to 15 mL of sample as waste oil to flush the drain pipe; then collect the remaining sample into a sample cup and remove the thermometer or sensor.
    • 11.2.11 Use GB/T 265 to determine the kinematic viscosity at 100℃ of the sample before and after shearing.

9. Qualitative and quantitative determination and calculation formulas

• 12.1 Use formula (2) to calculate the percentage viscosity loss of the sheared sample (PVL):
  • PVL = (V1 - V2) / V1 × 100% (2)
  • Where: V1— kinematic viscosity of the sample before shearing at 100℃, mm²/s; V2— kinematic viscosity of the sample after shearing at 100℃, mm²/s.
• 10.6.16 Viscosity loss value V = V1 - V2 (1), where: V1— kinematic viscosity of the sample before shearing at 100℃, mm²/s; V2— kinematic viscosity of the sample after shearing at 100℃, mm²/s.
• 3.3 Viscosity loss: the difference between the 100℃ kinematic viscosity of the sample before and after shearing.
• 3.4 Percentage viscosity loss: the viscosity loss value defined in clause 3.3 divided by the 100℃ kinematic viscosity of the sample before shearing, expressed as a percentage.
• 3.2 Calibration pressure: the pressure gauge pressure recorded when the pressure gauge shows a pressure within the range of 13.0 MPa to 18.0 MPa and the decrease in 100℃ kinematic viscosity of the RL-34 reference oil after shearing is within the range of 2.75 mm²/s to 2.85 mm²/s.

10. Precision

• 14.1 Precision: judge the reliability of the test results according to the following provisions (95% confidence level).
  • 14.1.1 Repeatability: the difference between two consecutive determination results obtained by the same operator using the same instrument under the same operating conditions on the same sample shall not exceed 1.05%.
  • 14.1.2 Reproducibility: the difference between two independent determination results obtained by different operators in different laboratories on the same sample shall not exceed (original value missing, requires confirmation against the source standard (source-text extraction)).
• 14.2 Bias: all test results are determined relative to the reference oil, so this standard does not establish bias.

11. Report

• 13 The report shall include at least the following information:
  • 13.1 Calibration pressure, MPa;
  • 13.2 Kinematic viscosity of the sample before shearing at 100℃, mm²/s;
  • 13.3 Kinematic viscosity of the sample after shearing at 100℃, mm²/s;
  • 13.4 Percentage viscosity loss calculated in clause 12.1 (PVL).

12. Referenced documents

• GB/T 265 Petroleum products—Determination of kinematic viscosity and calculation of dynamic viscosity
• GB/T 8029 Calibration oil for diesel engine fuel injection pumps
• CEC L-14-A-93 Determination of mechanical shear stability of lubricating oils containing polymers
• DIN 51382 Determination of shear stability of lubricating oils containing polymers by the diesel nozzle method
• ASTM D6278-02 Standard test method for shear stability of polymer-containing oils (European diesel nozzle apparatus method) (modified adoption)

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick-reference questions and answers