Bedienungsanleitung Operating Instructions. ZF-Servotest 600. ZF Lenksysteme GmbH D Schwäbisch Gmünd Telefon (07171) 31-0 Fax (07171)

Transcription

1 Bedienungsanleitung Operating Instructions ZF-Servotest 600 ZF Lenksysteme GmbH D Schwäbisch Gmünd Telefon (07171) 31-0 Fax (07171)

2 Table of Contents ZF-Servotest 600 Operating Instructions 1. Functional characteristics Representation of operating elements Technical data Hydraulic circuit diagram Description Connecting the Servotest to the steering system Hydraulic circuit schematic Functional testing of steering gear and pump Pump test Maximum pressure test Flow rate test Q- min Constant flow measurement Q- max Steering gear test Testing the hydraulic steering limiters Maximum pressure test Leakage oil measurement Testing the return to neutral of the control valve Checking the play Maintenance

3 Functional Characteristics 1. Functional characteristics 1.1 Representation of operating elements Throttle valve 2 Pressure sensor 3 Volume sensor 4 Temperature sensor 5 Ball cock 6 Flow control valve 7 Presure relief valve 8 Inlet connection M 22x1.5-15L 9 Outlet connection M 22x1.5-15L 10 Tank connection M 18x1.5-12L 11 Measured value indicator Multi-Handy 3010 ( Multi Mobile ) Key ch1 Key ch2 for pressure p for temperature T Key ch3 for oil flow Q 20

4 Functional Characteristics 1.2 Technical data Dimensions: Weight: Volume sensor: 380 mm x 355 mm x 180 mm 17 kg 0 70 dm³/min Temperature sensor: -50 to +200 C System pressure sensor: bar Pressure relief valve: bar Indicating instrument: Prior to any startup, please refer to the operating instructions of the Hydrotechnik Multi Mobile 3010 To be noted: After the Multi Mobile was switched on by pressing the ON key, the values for pressure p, temperature T and oil flow Q are shown triple-spaced on the display. To obtain an enlarged, double-spaced display of the measurement values, a value not currently needed can be blanked by pressing the respective key: ch1 for the pressure, ch2 for the temperature or ch3 for the oil flow. To have the blanked value represented again on the Multi Mobile display, press the respective key once more. 21

5 Functional Characteristics Max. operating temperature: 90 C Operating pressure: Accessories: adjustable up to 200 bar 2 pressure hoses 2 reducers 15/12L 1 union piece 15L 1 tube 12 1 connection for hose pipe Tank 1 measuring cable Ordering ref. No.: Hydraulic circuit diagram tank 10 adjustable up to 200 bar max. inlet 9 8 gauze filter 3-way flow control valve outlet fixed setting to 210 bar 22

6 Functional Characteristics 1.4 Description The Servotest 600 is designed for the testing of power steering gears and oil pumps on the vehicle. To this end the Servotest is installed at an easily accessible place in the steering system pressure line. All tests necessary for inspection or trouble shooting can now be implemented. By means of the built-in throttle valve (1) and the pressure relief valve (7) it is possible to simulate the action of the steering valve and, thus, to test the pump. After the electronic measuring equipment was switched on, the system pressure, the temperature and the oil flow are displayed on the Multi Mobile (11). The pressure relief valve (7) is adjustable up to 200 bar. Prior to beginning any testing set the maximum pressure indicated on the type plate of the steering gear or the pump. 23

7 Connecting the Servotest to the Steering System 2. Connecting the Servotest to the steering system To be noted: The figures in brackets refer to the numbering of the operating elements and components shown in the illustration on Page 2. Disconnect the pressure line coming from the pump and connect it to the Servotest inlet (8). Connect the pressure line leading to the steering gear to the Servotest output (9). For this purpose you may use the high pressure hoses and reducers which are part of the accessories. After fitting the pressure relief valve of the steering system as described under Item 3. b), lay a hose line between the Servotest Tank connection (10) and the vehicle oil tank (see illustration on Page 6). When attaching the hose lines to the Servotest or when removing them, take care to steady the connections with an engineer s wrench. Settings prior to testing: - throttle valve (1) and pressure relief valve (7) open - ball cock (5) closed - flow control valve (6) open = graduation mark on 10 (on dot mark) To be noted: To open the valves (1,7) turn them counter clockwise and the ball cock (5) clockwise Top up the oil in the oil tank. Bleed the steering system. When doing so, please conform to the instructions in the operating, maintenance and inspection manuals of the respective steering gear type. 24

8 oil tank pump steering gear Connecting the Servotest to the Steering System 2.1 Hydraulic circuit schematic 25

9 Functional Testing of Steering Gear and Pump 3. Functional testing of steering gear and pump To be noted: For the implementation of the tests described below it is essential to make a distinction between two types of steering systems. a) The pressure relief valve is incorporated in the pump or in a separate valve ahead of the Servotest. b) The pressure relief valve is incorporated in a separate valve aft of the Servotest or in the steering gear. If the Servotest is installed as per b), the components arranged ahead of the Servotest (pump, hoses and pipes) are safeguarded against excessive pressure during the test by the pressure relief valve incorporated in the Servotest. The components incorporating a pressure relief valve can be identified by the pressure indication engraved on the type plate. Heat the oil in the steering system to the specified test temperature of 50 C. 3.1 Pump test Attention: When the throttle valve (1) and the pressure relief valve (7) are closed during testing, by no means rotate the steering wheel at the same time for otherwise pressure peaks susceptible of damaging the pump or the Servotest may occur Maximum pressure test Press the ON key to switch the Multi Mobile on. Read the maximum pressure indicated on the type plate of the pump, the steering gear or the separate pressure relief valve. Close the throttle valve (1) at engine idling speed. Close the pressure relief valve (7) until the Multi Mobile displays the maximum pressure. When pumps with incorporated pressure relief valve are tested, after reaching maximum pressure close the pressure relief valve of the Servotest further by 1 more turn. Open the Valves ( 1 and 7) To be noted: Allow maximum pressure for a short time only (at maximum 10 s) for otherwise the inner components of the pump will be heated excessively, entailing a possible early wear of these components. The permissible variation from nominal pressure may not exceed 10%. Re-open the throttle valve (1). 26

10 Functional Testing of Steering Gear and Pump Testing the flow rate Q- min. Close the pressure relief Valve (7) and continue closing the throttle valve (1) until the test pressure indicated in Table I for the respective pump type is reached. For the minimum flow rate at test speed, please also refer to Table I. For higher speeds, the minimum flow rates can be looked up in Graphs I and II. Open the throttle valve (1) and the pressure relief valve (7). The speed should not be too high for otherwise it may happen that the measurement takes place in the flow control range of the pump already. If the values specified for pressure and flow rate are not attained, the pump or the pump drive or the separate valve is/are defective. Such defects have to be eliminated before continuing the inspection work Constant flow measurement Q-max. Continue raising the engine speed until the pump flow rate remains constant despite a further increase in engine speed. The pump is now in its flow control range. For the specified value of the flow rate, please refer to the spare parts list of the respective oil pump. On pumps with a dropping characteristic, the oil flow will decrease. -> see the Technical Data of the pump 27

11 Functional Testing of Steering Gear and Pump Table I Type Test Speed Test Pressure Minimum Flow Rate dm³ / min , , , , , , (*1) , , , , , , (passenger cars) , (commercial veh.) , , , (8,5 cm³/rev.) (9 cm³/rev.) , ,2 Circuit I ,0 Circuit II max. speed max. speed ,3 +0,3 0,3+0,3 0,3+0, For pump type 7682, the minimum flow rate and the test pressure depend on the nominal pressure. Test speed: 500 min -1. Nominal pressure Test pressure Minimum flow rate 65 bar 50 bar 4,2 dm³ / min 85 bar 65 bar 4,0 dm³ / min 95 bar 75 bar 3,9 dm³ / min 110 bar 90 bar 3,7 dm³ / min (*1) Model at the Training Room, with rotor set 7672! 28

12 pump speed min -1 Functional Testing of Steering Gear and Pump Graph I o Minimum values oil flow 29

13 pump speed min -1 Functional Testing of Steering Gear and Pump Graph II o Minimum values oil flow 30

14 Functional Testing of Steering Gear and Pump 3.2 Steering gear test Testing the hydraulic steering limiters For the setting values, please refer to the ZFLS Operating, Maintenance and Inspection Instructions or to vehicle manufacturers instructions Maximum pressure test Between the wheel lock stop components, insert thrust pieces of a thickness of approx. 15 mm which are designed such that the steering motion is stopped approx. ½ to ¾ steering wheel turn before reaching the end stop. Attention: Tools under pressure may be ejected avoid any direct visual contact with the tool. Depending on the axle version it may be necessary to use a special thrust piece specified by the vehicle manufacturer. To be noted: Thrust pieces must only be used for steering gears with hydraulic steering limiters. Close the pressure relief valve (7) and rotate the steering wheel to the right until reaching the stop, then pull it to the right for abt. 5 s, applying a force of N (10-20 kp). Repeat this measurement in the opposite (LH) direction of rotation. In steering systems with pressure relief valve at the pump and at the steering, the throttle valve (1) must be closed, that the display pressure is 20 Bar lower than the max. Value of the pressure relief valve at the steering. Only after this, the max. Pressure of the pressure relief valve of the pump can be measured. If it is found in this test that the oil pressure varies by more than 10% from the result of the maximum pump pressure test or from the nominal pressure shown on the type plate, the amount of leakage oil is too high or the pressure relief valve is defective....eliminate the defect 31

15 Functional Testing of Steering Gear and Pump Leakage oil measurement - For steering systems to para. 3.a) Pressure relief valve ahead of the Servotest Place thrust pieces of a thickness of approx. 15 mm on the wheel lock stop screws. Attention: Tools under pressure may be ejected avoid any direct visual contact with the tool. Depending on the axle version it may be necessary to use a special thrust piece specified by the vehicle manufacturer. To be noted: Thrust pieces must only be used for steering gears with hydraulic steering limiters. Open the throttle valve (1) and the pressure relief valve (7) and rotate the steering wheel in one direction until reaching the stop, then pull at the wheel for a short time (max. 5 s), applying a force of N (10-20 kp) to make sure the steering valve is fully closed. Repeat the test in the opposite direction of rotation of the steering wheel. - For the permissible leakage oil values please refer to Table II on Page For steering systems to para. 3.b) Pressure relief valve aft of the Servotest Place thrust pieces of a thickness of approx. 15 mm on the wheel lock stop screws. Remarks Attention and To be noted as above. Open the pressure relief valve (7) completely, close the throttle valve (1) and close the pressure relief valve (7) again far enough to cause a back pressure to build up which is 30 bar lower than the nominal pressure indicated on the type plate. Open the throttle valve (1) again. Rotate the steering wheel in one direction until reaching the stop, then pull at the wheel for a short time (max. 5 s), applying a force of N (10-20 kp) to make sure the steering valve is fully closed. Repeat the test in the opposite direction of rotation of the steering wheel. - For the permissible leakage oil values please refer to Table II on Page 34. If it is found that the leakage rate in one direction of rotation is higher than permitted either the steering limiting valve or internal sealing components are defective. If the leakage rate is too high in both directions, the pressure relief valve (7) or the internal sealing components may be defective. 32

16 Functional Testing of Steering Gear and Pump Additional leakage oil measurement on ZF Servocom steering gears Press the ON key to switch the Multi Mobile on. On ZF-Servocom steering gears, following the conventional leakage oil measurement as described under para.s a) or b) above, the leakage oil must be measured at a reduced oil flow and under the same conditions as described under para.s a) or b) above. Notes for the operation of the Servotest 600 when measuring the leakage oil on ZF- Servocom steering gears: In all tests, with the exception of this leakage oil measurement at reduced oil flow, the flow control valve (6) is fully open (graduation mark on 10 (on the dot mark)) and the ball cock (5) is closed. How to proceed to reduce the oil flow: For steering systems to para. 3. a) - Open the ball cock (5) - Close the pressure relief valve (7) - Close the throttle valve (1) until a pressure of bar is available - Close the flow control valve (6) until the oil flow is reduced to dm³/min - Open the throttle valve (1) again Next, carry out the test as described in para For steering systems to para. 3. b) - Open the ball cock (5) - Open the pressure relief valve (7) - Close the throttle valve (1) - Set the pressure relief valve (7) at a pressure 20 bar lower than the steering gear nominal pressure - Open the throttle valve (1) until a pressure of bar is available - With the flow control valve (6) set the oil flow to dm³/min - Fully open the throttle valve (1) Next, carry out the test as described in para

17 Functional Testing of Steering Gear and Pump Table II Type Leakage rate dm³/min ZF column-type power steering gears ZF rack and pinion power steering gears Types 7830 and 7847 with 150 bar ,5 1,5 2, ,0 0,7 ZF recirculating ball power steering gears ZF Servocom power steering gears ZF semi-integral power steering gears circuit II / * 7401 circuit II * * ,8 3,0 3,2 1,2 2,0 2,5 1,0 2,0 2,5 2,5 3,5 2,5 2,0 1,5 2,5 4,0 * Steering gear with valve sleeve > 24 dm³/min = leakage rate 4.0 dm³/min This table indicates standard values. For more detailed values, for instance for Servotronic type steering gears, please refer to the respective ZFLS Operating, Maintenance and Inspection Instructions. 34

18 Functional Testing of Steering Gear and Pump Testing the return to neutral of the control valve Press the ON key to switch the Multi Mobile on. Flow control valve (6) is closed, graduation mark on position 10 (on the dot mark Ball cock (5) is closed. While having a close look at the display, rotate the steering wheel to the left and to the right to raise the circulation pressure to approx. 20 bar. Each time the steering wheel is released slowly, the display reading must drop to its lowest original value. If this is not so, check the steering column for ease of operation. To this effect please refer to the ZFLS Operating, Maintenance and Inspection Instructions or to the respective vehicle manufacturers instructions. If despite a smooth operation of the steering column the lowest original position cannot be attained, the control valve of the steering is defective and the steering box has to be replaced Checking the play Additional tools are required to check the play. In this connection please refer to the notes in the ZFLS Operating, Maintenance and Inspection Instructions for the respective steering gear types. 35

19 Maintenance 4. Maintenance The design of the Servotest 600 tester enables easy operation and maintenance. No special knowledge is required. Whenever you start the Multi Mobile 3020 by Hydrotechnik, make sure you conform to manufacturer s operating instructions. 36