1、 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 1 of 2 NAVISTAR, INC. CEMS (CORPORATE ENGINEERING MATERIAL SPECI
2、FICATION) NUMBER: CEMS BT-21 TITLE: Hydraulic Performance Test CURRENT ISSUE DATE: August 2009 WRITTEN/REVIEWED BY: Materials Engineering APPROVED BY: Materials Engineering SUPERSEDES ISSUE OF: October 2001 PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRENT REVISION This specification may
3、involve hazardous materials, equipment, and procedures. This specification does not purport to address all of the safety issues associated with its use. The user is responsible to consult appropriate safety and health practices and to determine the applicability of regulatory limits prior to use. Ch
4、ange Notice: Replaced “International Truck and Engine Corporation” with “Navistar, Inc.” per corporate directive. 1.0 SCOPE This method covers a test procedure for the determination of compatibility of combination hydraulic and transmission fluids with “O” rings used in Navistar machines. 2.0 APPARA
5、TUS 2.1 Two double acting cylinders with rods connected. 2.2 Each cylinder composed of piston taking seven “O” rings. 2.3 Two identical heads each taking three rod seal “O” rings and three tube seal “O” rings. 2.4 Each “O” ring is pressurized equally. 2.5 Piston diameter: 3 inches (76 mm). 2.6 Rod d
6、iameter: 1-1/8 inches (29 mm). 2.7 Tube and rod finished to 6 microinches (0.152 mm) AA. 3.0 MATERIAL “O” rings for test must meet the Navistar Engineering Drawing FZG-467 for Hydraulic “O” Rings. Ring Sizes: 2-5/8 x 3 x 3/16 inches (67 x 76 x 5 mm); 2-3/4 x 3 x 1/8 inches (70 x 76 x 3 mm); 1-1/8 x
7、1-3/8 x 1/8 inches (29 x 35 x 3 mm). 4.0 PROCEDURE Cylinders cycled such that on alternate strokes one cylinder loads the other. Pressure is applied to each side of each cylinder an equal length of time and is periodically switched. Test conditions are as follows: 4.1 Pressure during stroke: 1500 50
8、 psi (10.3 0.3 MPa). 4.2 Pressure at end of stroke: 1600 psi (11.0 MPa) max. 4.3 Cycle rate: 10 cpm. 4.4 Length of stroke: 12 inches (305 mm). 4.5 Length of test, 70 durometer rings: 100 hours. 4.6 Length of test, 90 durometer rings: 200 hours. 4.7 Fluid temperature: 235 to 240F (113 to 116C). 4.8 F
9、iltration: 25 mm, min. 4.9 At end of test, disassemble the cylinders and grade the “O” rings per “O” Ring Failure Classification Guide shown on page 2. NUMBER: CEMS BT-21 TITLE Hydraulic Performance Test CURRENT ISSUE DATE: August 2009 This document is restricted and may not be sent outside Navistar
10、 Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 2 of 2 5.0 REPORT Report the classification that the “O” rings meet. “O” RING FAILURE CLASSIFICATION GUIDE Condition: (listed in
11、ascending order) Classification I II III IV V A permanent set see below none noticeable sharp edge no sealing B swell or shrinkage within specifications out of specification not noticeable visually out of specification noticeable visually malfunction C hardness change within specifications out of sp
12、ecification not sealing properly brittle or cracked D pitting none noticeable excessive leakage extreme not sealing E blistering none noticeable excessive not sealing F twist or roll none indications of severe fractured G extrusion none slight excessive not sealing H wear (abrasion) none slight leak
13、age within specifications excessive not within leakage specification not sealing J material degradation not visually apparent slight excessive extreme K fracture none none surface or short and deep deep separations Classification I: Not distinguishable from new condition by any means. Classification
14、 II: Not distinguishable from new by visual inspection; however, slight material changes have occurred resulting in a change in volume or hardness. Any change will be within specifications. The “O” ring is reusable. Classification III Functioning per specifications but would not be reused in a norma
15、l rebuild because of visible damage or material change out of specifications. Classification IV Functioning; however, inspection reveals progressive damage or material degradation which would result in unit failure. Classification V: Not functioning because of extensive damage or material degradation.
