GB/T 12541-2023Motor vehicles passing capacity test method (English PDF)

4.1 General Rule

4.1.1 Vehicle preparation and test meteorological conditions shall comply with the stipulations of GB/T 12534.

4.1.2 The amount of wear on the tread pattern of the test vehicle shall not exceed 1/5 of the original thread height.

4.1.3 When the same model has different tyre models, the vehicle equipped with tyres with the smallest diameter shall be selected for the test.

4.1.4 Adjust the tyre pressure of the test vehicle to the pressure value required by design, when equipped with adjustable pressure tyres, in accordance with the manufacturer's design requirements, adjust to the appropriate pressure.

4.1.5 For vehicles equipped with adjustable suspension, adjust the test vehicle to the suspension state required by the manufacturer.

4.1.6 The test vehicle shall be loaded in accordance with the maximum design total mass, axle load and wheel load specified by the manufacturer.

4.2 Measurement Parameters and Accuracy The measurement parameters and accuracy are shown in Table 1.

5.2.1.3 If there is no special requirement from the manufacturer, adjust the vehicle to the maximum design total mass state.

5.2.2 Vertical obstacles

5.2.2.1 The vehicle can drive up / down the vertical obstacles in forward gear and up / down the vertical obstacles in reverse gear.

5.2.2.2 Place the manual transmission in the lowest forward gear / reverse gear. If there is an auxiliary transmission gear, place it also in the lowest forward gear. Place the automatic transmission in the forward gear / reverse gear (or in accordance with the manufacturer's design requirements) and adjust the all-wheel drive vehicle to the all-wheel drive state.

5.2.2.3 When driving on a vertical obstacle, drive the vehicle at a speed not greater than 5 km/h, until the wheels approach the vertical obstacle, then, brake and stop, keep the gear unchanged, release the brake pedal, select an appropriate throttle opening, and drive forward / reverse on the vertical obstacle.

5.2.2.4 When driving down a vertical obstacle, drive the vehicle at a speed not greater than 5 km/h, until the wheels approach the vertical obstacle, then, brake and stop, keep the gear unchanged, appropriately adjust the brake pedal force, and slowly drive forward / reverse down the vertical obstacle.

5.2.2.5 Observe the movement of the vehicle and whether its components are in contact or collide with terrain facilities, or interfere with each other during the process of passing the vertical obstacle.

5.2.2.6 During the process of the vehicle passing the vertical obstacle, if the vehicle, except the wheels, does not contact or collide with the vertical obstacle, or there is no inter-component interference, and in the parking inspection after passing, there is no collision damage of components, damage or looseness of connectors, and abnormal operation of the assembly, etc., then, vertical obstacles with other parameters can be chosen; repeat 5.2.2.2 ~ 5.2.2.5, until reaching or approaching the maximum value that can be passed; record the passing conditions in the corresponding record table (see Table B.3).

5.2.2.7 During the process of the vehicle passing the vertical obstacle, if the vehicle, except the wheels, does contact or collide with the vertical obstacle, or there is inter-component interference, or if there is a failure in passing, or in the parking inspection after passing, there is collision damage of components, damage or looseness of connects, and abnormal operation of the assembly, etc., after analyzing the causes and recovering the vehicle to the normal state, in accordance with Appendix C, re-select the height of the vertical obstacle and in accordance with 5.2.2.2 ~ 5.2.2.6, re-conduct the test.

5.2.3 Convex ridges, horizontal ditches, road ditches, craters and twisted roads

5.2.3.1 Place the manual transmission in the lowest gear, and if there is an auxiliary transmission gear, place it also in the lowest gear. Place the automatic transmission in the forward gear (or in accordance with the manufacturer's design requirements), and adjust the all-wheel drive vehicle to the all-wheel drive state.

5.2.3.2 Drive the vehicle at a speed not greater than 5 km/h, until the front wheels approach the corresponding terrain, then, brake and stop, keep the gear unchanged, release the brake pedal, select an appropriate throttle opening, pass the corresponding terrain facilities, and observe the movement of the vehicle and whether its components are in contact with or collide with the terrain facilities, or whether there is inter-component interference during the process of passing the corresponding terrain.

5.2.3.3 During the process of the vehicle passing the terrain, if the vehicle, except the wheels, does not contact or collide with the terrain facilities, or there is no inter-component interference, and in the parking inspection after passing, there is no collision damage of components, damage or looseness of connectors, and abnormal operation of the assembly, etc., then, terrain facilities with other parameters can be chosen; repeat 5.2.3.1 ~

5.2.3.2 until reaching or approaching the maximum value that can be passed; record each test condition in the corresponding record tables (see Table B.4 ~ Table B.8).

5.2.3.4 During the process of the vehicle passing the terrain, if the vehicle, except the wheels, does contact or collide with the terrain facilities, or there is inter-component interference, or if there is a failure in passing, or in the parking inspection after passing, there is collision damage of components, damage or looseness of connects, and abnormal operation of the assembly, etc., after analyzing the causes and recovering the vehicle to the normal state, in accordance with Appendix C, re-select the parameters of the terrain and in accordance with 5.2.3.1 ~ 5.2.3.3, re- conduct the test.

5.2.3.5 In accordance with the manufacturer's requirements, during the twisted road test, the vehicle can be stopped and start again when the diagonal wheels are at the highest point of the twisted road, and record the vehicle starting.

5.2.4 Wading pools

5.2.4.1 Place the manual transmission in the lowest forward gear, and if there is an auxiliary transmission gear, it shall be selected in accordance with the manufacturer's requirements. Place the automatic transmission in the forward gear (or in accordance with the manufacturer's design requirements), and adjust the all-wheel drive vehicle to the all-wheel drive state.

5.2.4.2 In accordance with the technical requirements for wading specified by the vehicle manufacturer, check and adjust the technical condition of the vehicle. Electric passenger cars shall satisfy the wading requirements specified in GB 38032, and other electric vehicles shall satisfy the wading requirements specified in GB 18384.

5.2.4.3 Steadily drive at an initial speed of no more than 10 km/h into a wading pool with a selected depth, and drive for at least 500 m. If the pool distance is less than 500 m, the test shall be repeated, so that the cumulative wading distance is not less than 500 m, and the total test time, including the vehicle outside the pool, shall be less than 20 min.

5.2.4.4 After the vehicle passes the wading pool, if there is no water ingress in the cab, luggage compartment, air filter element, carbon tank and various oil fluids, the starter, clutch, brake system, bottom guard, electrical accessories and instruments are normally working, and the insulation resistance of the electric vehicle is normal, the depth of the wading pool can be adjusted, repeat 5.2.4.1 ~ 5.2.4.3, until reaching or approaching the maximum value that can be passed. Record the wading depth, passing time, passing distance and passing conditions in the corresponding record table (see Table B.9).

5.2.4.5 During the wading process, if the engine flames out, or water enters the cab, luggage compartment, air filter element, carbon tank and various oil fluids after the vehicle passes the wading pool, the starter, clutch, brake system, bottom guard, electrical accessories and instruments are abnormally working, and the insulation resistance of the electric vehicle is abnormal, after analyzing the causes and recovering the vehicle to the normal state, in accordance with Appendix C, re-select the depth of the wading pool and in accordance with 5.2.4.1 ~ 5.2.4.4, re-conduct the test. During the wading process, if the engine flames out, it is not suitable to start again, and it can be dragged out of the wading pool. If the manufacturer has a demand for re-start verification, it can also be implemented in accordance with the actual requirements.

5.2.5 Side slopes

5.2.5.1 Place the manual transmission in the lowest gear, and if there is an auxiliary transmission gear, it shall be selected in accordance with the manufacturer's requirements. Place the automatic transmission in the forward gear (or in accordance with the manufacturer's design requirements), and adjust the all-wheel drive vehicle to the all-wheel drive state.

5.2.5.2 Park the vehicle on the junction near the side slope.

5.2.5.3 After starting, pass the side slope at a constant speed of not greater than 10 km/h. The heading direction of the vehicle shall be parallel to the direction of the side slope road surface, and respectively drive forward and backward once.

5.2.5.4 If the vehicle does not appear to slide down the side slope or roll over, or the instrument does not issue a failure warning during the driving, side slopes with other parameters can be chosen. Repeat 5.2.5.1 ~ 5.2.5.3, until reaching or approaching the maximum gradient that can be passed. Record the side slope gradient, side slope length, passing time and passing conditions in the corresponding record table (see Table B.10).

5.2.5.5 If the vehicle has a tendency to slide down the side slope or roll over, or the instrument issues a failure warning during the driving, after analyzing the causes and recovering the vehicle to the normal state, in accordance with Appendix C, re-select the side slope, and in accordance with 5.2.5.1 ~ 5.2.5.4, re-conduct the test.

5.2.6 Ramps

5.2.6.1 The vehicle can drive up / down the ramps in forward gear and up / down the ramps in reverse gear. Tanalpham 100%

---the maximum gradeability; alpha1

---the actual angle of gradient during the test, expressed in (); Ga

---the maximum design total mass of the vehicle, expressed in (kg); i1

---the lowest gear overall speed ratio; i2

---the actual overall speed ratio; Ga1

---the actual total mass of the vehicle, expressed in (kg); f

---the rolling resistance coefficient, generally take 0.01.

5.3.1 Test preparation

5.3.1.1 In accordance with the manufacturer's design requirements, and Appendix D, select the soft ground test site; before the test, the vehicle shall be thoroughly warmed up.

5.3.1.2 In the selected test site, divide the predicted road section and the measurement road section, with each section not less than 20 m, and mark them.

5.3.1.3 The test vehicle shall be equipped with instruments and equipment, such as: wheel tachometer, speedometer and engine tachometer, etc.

5.3.1.4 Place the manual transmission gear in the lowest forward gear (except for rolling resistance coefficient and rut depth measurement). If there is an auxiliary transmission gear, place it also in the lowest forward gear. Place the automatic transmission in the forward gear (or in accordance with the manufacturer's design requirements) and adjust the all-wheel drive vehicle to the all-wheel drive state.

5.3.1.5 Adjust the vehicle to the maximum design total mass state.

5.3.2 Rolling resistance coefficient and rut depth

5.3.2.1 Park the test vehicle on the predicted road section and place the transmission in neutral.

5.3.2.2 The tractor is connected to the test vehicle through a drawbar and a tension gauge. Keep the height of the drawbars at both ends of the test vehicle and the tractor consistent, and coincide with the vertical plane of the longitudinal centerline of the test vehicle.

5.3.2.3 The tractor tows the test vehicle at a speed not greater than 5 km/h to pass the measurement road section at a constant speed. Collect the vehicle speed and towing force (F).