1、SURFACE VEHICLERECOMMENDED PRACTICEJ1374SEP2014Issued 1985-05Revised 2014-09Superseding J1374 MAY1985Hydraulic Cylinder Rod Seal Endurance Test ProcedureRATIONALEThis Standard is revised to clarify definitions and incorporate ISO 4406 as reference for fluid cleanliness1. SCOPEApplies to hydraulic se
2、als used to seal the rods of hydraulic cylinders which are components of Off-Road Self-Propelled Work Machines defined in SAE J1116.1.1 PurposeTo establish an endurance testing and reporting procedure for reciprocating cylinder rod hydraulic seals to provide a basis for seal comparison.2. REFERENCES
3、2.1 Applicable DocumentsThe following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply.2.1.1 SAE PublicationsAvailable from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001,
4、 Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.SAE J1116 Categories of Off-Road Work MachinesSAE J1176 External Leakage Classifications for Hydraulic SystemsSAE J1276 Standardized Fluid for Hydraulic Component Tests_SAE Technical Standards Board Rules provide t
5、hat: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.”S
6、AE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions.Copyright 2014 SAE InternationalAll rights reserved. No part of this publication may be reproduced, stored in a retrieva
7、l system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE.TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)Tel: +1 724-776-4970 (outside USA)Fax: 724-776-0790Email: CustomerServi
8、cesae.orgSAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedbackon this Technical Report, please visithttp:/www.sae.org/technical/standards/J1374_201409SAE INTERNATIONAL J1374 Revised SEP2014 Page 2 of 72.1.2 ISO PublicationsAvailable from American National Standards Institute,
9、25 West 43rd Street, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org.ISO 4406 Hydraulic Fluid Power Fluids - Method for coding the level of contamination by solid particles3. DEFINITIONS3.1 STROKEThe maximum distance traveled in one direction by the rod.3.2 RETRACT STROKEWith reference to a
10、 single rod hydraulic cylinder, the movement of the cylinder rod into the cylinder.3.3 EXTEND STROKEWith reference to a single rod hydraulic cylinder, the movement of the cylinder rod out of the cylinder.3.4 CYCLEThe movement of the piston and rod from its starting point and return to its original p
11、osition for a specified test stroke length.3.5 RATED PRESSUREThe continuous duty operating pressure specified by the seal manufacturer.3.6 LEAKAGE RATEThe amount of leakage per number of cycles. This is specified in units of mL/1000 cycles (in3/1000 cycles) and mL/kilometers (in3/ft).3.7 PRIMARY TES
12、T SEALRod seal set which has high pressure applied during the retract stroke.3.8 SECONDARY TEST SEALRod seal which has high pressure applied during extend stroke.SAE INTERNATIONAL J1374 Revised SEP2014 Page 3 of 74. TEST EQUIPMENT AND TEST PARAMETERS4.1 Test Equipment4.1.1 Test FluidFluid shall be p
13、er SAE J1276 unless otherwise specified.NOTE: For low temperature option on test procedure, a low temperature fluid should be used.4.1.2 Test ApparatusA standard cycle test set up is shown in Figures 1 and 2, and an optional cycle test set up for overrunning load is shown in Figures 2 and 4.If a rod
14、 wiper seal is used to facilitate gathering leakage, it shall not contribute to sealing of the chamber. Seal gland dimensions and surface finish shall be as specified by seal supplier.4.1.3 Test RodSurface Finish Ra 0.20 Pm 0.40 Pm (8 microinch 16 microinch) hard chrome plated and polished. Inductio
15、n hardening is optional. With each new seal test, use a new rod or one that has been re-plated and polished. If rod finish in proposed application differs, test should be made with surface finish of the application.4.2 Test Parameters4.2.1 Contamination Level OF Test FluidThe maximum contamination l
16、evel of the test fluid shall not exceed ISO 4406 Code -/17/14.4.2.2 Accuracy of MeasurementThe accuracy of measurements, unless otherwise stated, shall be;Temperature 3 C, Pressure 2%, Leakage 2%, Time 2%, and Length 2%.4.2.3 Stroke300 mm 5 mm (12 in 0.2 in) or as agreed upon between user and suppli
17、er.4.2.4 Rod Speed0.30 m/s 0.03 m/s (60 fpm 6 fpm) or as agreed upon between user and supplier.SAE INTERNATIONAL J1374 Revised SEP2014 Page 4 of 7FIGURE 1 - TYPICAL TEST SETUP FOR CYLINDER ROD SEAL ENDURANCE TESTFIGURE 2 - ROD SEAL TEST CHAMBER (TYPICAL)4.2.5 Pressure-stroke Cycle ProfilePressurized
18、 to 110% of rated pressure for retract portion of stroking cycle.The pressure rise-rate shall be 100 MPa/s 20 MPa/s. (14 500 psi/s 2900 psi/s.) The peak pressure overshoot shall not exceed 120% of rated pressure. Pressure during the extend portion of the stroking cycle shall not exceed 310 kPa (45 p
19、si). Rod movement in each direction shall not start until the pressure stabilizes within + 2.5%.SAE INTERNATIONAL J1374 Revised SEP2014 Page 5 of 7FIGURE 3 - TYPICAL PRESSURE-STROKE CYCLE4.2.6 Fluid TemperatureThe temperature of the fluid shall be measured in the test chamber and is to be 105 C 3 C
20、(221 F 5 F) for 80% of the test and 30 C 3 C (86 F 5 F) for 20% of the test. Other temperatures could be used as specified by the seal supplier, depending on material and test fluid.4.2.7 Test DurationThe test shall run for 500 000 cycles or until maximum leakage rate of the test seal is exceeded.4.
21、2.7.1 The number of samples tested of each seal shall be a minimum of four.FIGURE 4 - TYPICAL PLOT OF DATA PRESENTATIONSAE INTERNATIONAL J1374 Revised SEP2014 Page 6 of 7FIGURE 5 - TYPICAL TEST ARRANGEMENT FOR CYLINDER ROD SEAL WITH OVER-RUNNING LOAD5. TEST PROCEDURE5.1 Standard Test5.1.1 For 80 000
22、 cycles, operate at a temperature of 105 C 3 C (221 F 5 F) and then for 20 000 cycles, operate at a temperature of 30 C 3 C (86 F 5 F) measured per paragraph 4.2.5. The stroke, rod speed, and pressure cycles shall be per paragraph 4.2.5.1.2 Perform step 5.1.1 five times.5.1.3 Leakage MeasurementsThe
23、 leakage from the seals shall be collected continuously during the test. Record leakage every 20 000 cycles (maximum) in units of mL/1000 cycles (in3/1000 cycles) and mL/kilometers (in3/ft).5.2 Optional Tests5.2.1 Static Leakage5.2.1.1 A static leakage measurement should be made at 100 000, 300 000
24、and 500 000 cycles.SAE INTERNATIONAL J1374 Revised SEP2014 Page 7 of 75.2.1.2 Static Leakage ProcedureDisconnect test chamber from pressure source and external actuating force. Establish a fluid level at 70 mm to 120 mm(2.75 in to 4.75 in) above outer diameter point at the top of rod seal with stand
25、 pipe open to atmosphere, with the oil and test chamber at 21 C + 3 C (70 F + 5 F) and test stationary, measure leakage for a 24 hour period. The leakage should be recorded in units of mL (in3).5.2.2 Cycle Test for Cylinders with an Over-Running Load During the Retract Stroke5.2.2.1 Test ProcedureRu
26、n the standard test 5.1 with the pressure profile per paragraph 5.2.2.2.5.2.2.2 Pressure ProfileOn the extend stroke of the test rod, pressurize the test chamber to 110% of rated pressure of the seal. On the retract stroke of the test rod, the pressure in the test chamber should be lowered to a 580
27、mm 680 mm (23 in 27 in) of Hg vacuum. (See Figure 4 - Primary seal is under vacuum during retract stroke).5.2.3 Cold Soak Cycles Test5.2.3.1 After 20% of the standard test 5.1 (100 000 cycles) has been completed, cold soak test set up to -40 C (-40 F)maximum for 48 hours. Operate test per paragraphs
28、 4.2.2, 4.2.3, and 4.2.4 for 100 cycles measuring leakage rate. (NOTE: Special low temperature fluid should be used for this portion of the test.) Temperature of test fluid can rise to a maximum of -18 C (0 F) during these cycles. Other temperatures could be used as agreed upon by manufacturer and d
29、epending on material.6. PRESENTATION OF DATA6.1 Record leakage as measured per 5.1.3.6.2 Plot data per Figure 3.6.3 Record all dimensions of seal, cavity, and rod including rod and cavity surface finish before and after test.6.4 Record optional test parameters if used.7. NOTES7.1 Marginal IndiciaA c
30、hange bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only.PREPARED BY THE SAE CTTC C1, HYDRAULIC SYSTEMS COMMITTEE
