1、WORLDWIDEENGINEERINGSTANDARDSMaterial Specification GMW3056Hydraulic Brake Hose Assembly Copyright 2012 General Motors Company All Rights ReservedOctober 2012 Originating Department: North American Engineering Standards Page 1 of 301 ScopeThis specification defines the requirements for hydraulic bra
2、ke (jounce) hose assemblies. This hose assemblyis suitable for use at temperatures of -40 C to 120 C, and operating pressures up to 20.7 MPa.1.1 Material Description.1.1.1 Hose Construction.1.1.1.1 Inner Tube. The inner tube of the hose shall consist of a smooth inner rubber tube of ethylenepropylen
3、e diene monomer (EPDM) or a blend of ethylene propylene diene monomer and isobutene-isoprenerubber (EPDM-IIR). There shall be no materials in the tube compound extractable through exposure to eitherDOT 3 or DOT 4 brake fluids, as evidenced by 0 or positive values for volume change when the hose is t
4、estedto the requirements of section 3.1.3.4 for each of the two fluids, DOT 3 and DOT 4. No halogenated butylpolymer may be added to the rubber of the inner tube.1.1.1.2 Reinforcement. The reinforcement for the hose shall consist of two layers of polyvinyl alcohol (PVA) orrayon. A rubber cushion lin
5、er may be placed between the two layers of reinforcement. Alternativereinforcement materials may be considered after review and approval by the GM Materials Engineer issuingthe specification approval.1.1.1.3 Cover. The outer cover of the hose shall consist of a layer of EPDM.1.1.2 Coupling Construct
6、ion.1.1.2.1 Coupling Design. The coupling shall be designed, inserted, swaged, or crimped so that no internaltube abrasions, cuts or flaws shall result under any condition or combination of assembly componentdimensioning or tolerancing allowed by supplier production specifications, or under any cond
7、ition of rubberhose compression allowed by supplier production specifications.1.1.2.2 Corners. Sharp corners shall be avoided where the coupling contacts the tube to prevent cutting of thehose when subjected to internal pressure.1.1.2.3 Tube Insert. The tube insert must not extend past the end of th
8、e crimp shell after crimping, and theend of the tube insert must be radiused to eliminate burrs or sharp edges which might cause hose damageunder conditions of assembly vibration or pressure impulse.1.1.2.4 Damage. Damage to hose rubber or reinforcement generated by the crimping of the hose is notpe
9、rmissible under any possible production manufacturing conditions or supplier production tolerance stack-up,including variations in hose compression concentricity.1.1.2.5 Tube Collapse. Metal tube insert collapse during crimping is not permissible, except when thiscollapse is limited, predictable, co
10、ntrollable, and does not increase the potential for assembly leakage or othermalfunction.1.1.2.6 Design Restrictions. Grooves, upsets, or serrations are not permitted on the tube stem outsidediameter (OD) or on the crimp shell inside diameter (ID) except that these grooves, upsets, or serrations do
11、notcause hose cutting or other damage under any condition or combination of assembly component dimensioningor tolerancing allowed by supplier production specifications, or under any condition of rubber hosecompression allowed by supplier production specifications.1.1.2.7 Skiving, Adhesives. Skiving
12、of the hose is not permissible. Use of adhesives in the crimped joint is notpermissible.1.1.2.8 Flow Requirements. The coupling shall be designed for low flow restriction.1.1.2.9 Fluid Compatibility. All hose assemblies supplied to this specification must be compatible with thefollowing brake fluids
13、:Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3056 Copyright 2012 General Motors Company All Rights ReservedOctober 2012 Page 2 of 30x
14、 DOT 3x DOT 4x DOT 4+x DOT 4+1.1.2.10 Dimensions and Tolerances. Bulk hose shall conform to the dimensions shown in Table 1.Table 1: Bulk Hose DimensionsInside Diameter Millimeter (mm) Inch (in)3.0 1/83.2 1/84.0 3/164.5 3/164.8 3/165.0 3/161.1.3 Material Identification and Marking. To properly defin
15、e the hose, the material specification number(GMW3056) is to be referenced. The hose marking must conform to labeling requirements specifyinggovernment regulations such as United States of America Federal Motor Vehicle Safety Standard 106 (FMVSS106).For China usage, the supplier is responsible to co
16、ntact the China Quality Certificate Center for ChinaCompulsory Certificate (CCC) activities and ensure the vacuum hose/tubes meet the China CompulsoryCertificate requirements (reference CNCA-02C-063). All saleable parts shall have CCC markings after properauthorization. A copy of the certificate for
17、 the part shall be sent to GM Engineering before the Production PartApproval Process (PPAP) required date. This applies to both production parts and parts for service. Thisrequirement applies to all saleable hoses including those for service.1.2 Symbols. Not applicable.1.3 Typical Applications. Hydr
18、aulic brake (jounce) hose assemblies.2 ReferencesNote: Only the latest approved standards are applicable unless otherwise specified.2.1 External Standards/Specifications.ASTM D380 ASTM D865 ISO 36 ISO 7500-1ASTM D395 ASTM D2240 ISO 37 ISO 7619-1ASTM D412 ASTM E4 ISO 188 ISO 9227ASTM D413 CNCA-02C-06
19、3 ISO 815 SAE J1401ASTM D471 FMVSS 106 ISO 18172.2 GM Standards/Specifications.GM9698P GMW3356 GMW14872 GMW16837GME L0004 GMW14361 GMW15272 Opel 263GMW3059 GMW14362 GMW15387GMW3221 GMW14731 GMW160722.3 Additional References.x Drawing 9442997x TMC003 Material Safety Data Sheet guidance documents (ava
20、ilable at ).Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3056 Copyright 2012 General Motors Company All Rights ReservedOctober 2012 Pa
21、ge 3 of 303 Requirements3.1 Requirements on Test Specimens. Reference GMW3221.3.1.1 General Test Requirements. Ambient temperature test conditions shall be held to 23 C 5 C. Allother temperatures except 23 C 5 C shall be held to 3 C, and all pressures to -0/+690 kPa unlessotherwise noted. Where DOT
22、3 fluid is referenced for test purposes, Delco Supreme 11 or Union CarbidePM6664 meeting specification GMW16072 shall be used. Where DOT 4 fluid is referenced for test purposes,BASF HYDRAULAN 404 fluid meeting specification GMW3356 shall be used.Additional general test requirements are referenced in
23、 section 3.1.4. It is suggested that this section be readfirst before reading 3.1 through 3.4.3.1.1.1 Oil Resistance Test. See Table 2.3.1.1.1.1 Test Procedure. Six hose assembly samples at nominal hose compression are to be tested usingDOT 4 brake fluid meeting GMW3356.3.1.1.1.2 Fluid Fill and Oil
24、Immersion. The hose assembly shall be filled with brake fluid, sealed, immersed inoil according to GME L0004 and stored for 48 h at 70 C 3 C.3.1.1.1.3 Acceptance Determination. The outer diameter of the hose shall not increase more than 15% afterstorage.Table 2: Oil Resistance TestTest Requirement P
25、ass CriteriaOil Resistance of Rubber Cover 48 h at 70 qC Maximum swell shall be no more than 15%3.1.1.2 Stress-Corrosion Cracking. See Table 3.3.1.1.2.1 Test Procedure. Twelve hose assembly samples at nominal hose compression are to be exposed toan atmosphere of ammonia as the corrosive medium for 4
26、 h. The test shall be performed at a temperature of23 C r 3 C.3.1.1.2.2 Test Method. Equipment and test procedure shall be prepared in accordance with test procedureGMW14731.3.1.1.2.3 Acceptance Determination. Following examination under 7x magnification, the test piece shall befree of cracks.Table
27、3: Stress-Corrosion CrackingTest Requirement Pass CriteriaStress Corrosion Cracking 4 h at 23 C No evidence of cracks3.1.1.3 Static Ozone Test. See Table 4.3.1.1.3.1 Test Procedure. Six hose samples shall be tested. After removing any armor on the sample, bend abrake hose 360 degrees around a mandre
28、l and bind the ends. Mandrel diameter is to be 76.2 mm for 3.0 mmID hose, and 88.9 mm for 4.5 mm ID hose. In the case of a hose sample shorter than the circumference of thecylinder, bend the hose so that as much of its length as possible is in contact. The cylinder and binding shallbe made of metal
29、or materials that consume the minimum of ozone. If the hose collapses when bent aroundthe cylinder, provide for internal support of the hose by use of a metal liner.3.1.1.3.2 Hose Conditioning. Condition the hose on the cylinder for 24 h 0.5 h in ozone-free air at roomtemperature and then place it i
30、n an exposure chamber containing ozone in the proportion of100 pphm 10 pphm for 336 h 2 h. Ambient air temperature in the chamber during the test shall be40 C 2 C.3.1.1.3.3 Examination Procedure. Examine the cover of the hose for cracks under 7x magnification, ignoringthe areas immediately adjacent
31、to or within the area covered by the binding. Record whether or not cracks inthe hose are present.Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STAN
32、DARDS GMW3056 Copyright 2012 General Motors Company All Rights ReservedOctober 2012 Page 4 of 303.1.1.3.4 Acceptance Determination. No cracks shall be visible under 7x magnification.Table 4: Static Ozone TestTest Requirement Pass CriteriaStatic Ozone 336 h No cracks shall be visible after336 h of te
33、sting3.1.1.4 Dynamic Ozone Test. See Table 5.3.1.1.4.1 Test Procedure. Six hose samples shall be tested. Conduct the test per SAE J1401, 3.2.13. Testduration is to be 840 h.3.1.1.4.2 Acceptance Determination. No cracks will be visible on the hose under 7x magnification after 840 hof testing.Table 5:
34、 Dynamic Ozone TestTest Requirement Pass CriteriaDynamic Ozone 840 h No cracks shall be visible after840 h of testing3.1.2 Mechanical Requirements.3.1.2.1 Leak Test. See Table 6.3.1.2.1.1 Test Procedure. The test assembly shall be pressurized with air or an inert gas to a minimumpressure of 10.3 MPa
35、 (1494 psig), maximum pressure of 14.5 MPa (2103 psig). Pressure shall be held for aminimum of 10 s and a maximum of 25 s.3.1.2.1.2 Acceptance Determination. There shall be no evidence of leakage at the coupling or in the hosemember.3.1.2.1.3 Production Process Requirement. This test, or equivalent
36、safeguard, must be employed for 100%of production parts. The method of testing shall be determined by the manufacturer and approved by the GMMaterials Engineer issuing the Engineering Source Approval for the brake hose assembly.Table 6: Leak TestTest Requirement Pass CriteriaLeak 10.3 MPa to 14.5 MP
37、a(1495 psig to 2103 psig) No evidence of leakage3.1.2.2 Burst Test. See Table 7.3.1.2.2.1 Test Apparatus. The test apparatus shall consist of a pressure source capable of generating fluidpressure of 172 MPa/minute 69 MPa/minute (25 000 psig/minute 10 000 psig/minute), at an increasing rateand a syst
38、em in which the internal fluid pressure of the hose assembly can be controlled and measured,provision for filling the hose with water and hardware as required that is adapted to high-pressure work. Thepressure shall be obtained by a suitable means and measured with a calibrated gage. All piping andc
39、onnections shall be smooth bore with a minimum of recesses or offsets so that air may be freely removedfrom the system before running each test. The apparatus described for the expansion test may be used whenit conforms to these requirements.3.1.2.2.2 Test Procedure. Eighteen assemblies are to be te
40、sted; six at minimum hose compression, six atnominal hose compression, and six at maximum hose compression. Connect the specimen to the pressuresystem and fill completely with water allowing all air to escape. Moving the hose back and forth may facilitateremoval of air bubbles. Apply 41.4 MPa + 2.1/
41、-0 MPa (6000 psig +300/-0 psig) pressure at the rate specified inCopyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3056 Copyright 2012 Gene
42、ral Motors Company All Rights ReservedOctober 2012 Page 5 of 303.1.2.2.1 and hold for 2 minutes (+0/110 s). At the expiration of this hold period, increase the pressure at therate specified in 3.1.2.2.1 until the hose bursts. Read the maximum pressure obtained on the calibrated gageto the nearest 0.
43、7 MPa (100 psig) and record as the burst strength of the hose assembly. For hose assembliespre-conditioned by temperature or fluid exposure, the hold pressure shall be 27.6 MPa +2.1/-0 MPa(4000 psig +300/-0 psig), instead of 41.4 MPa +2.1/-0 MPa (6000 psig +300/-0 psig).3.1.2.2.3 Acceptance Determin
44、ation. There must be no leaks or blisters in the hose assembly at the holdpressure of 41.4 MPa (6000 psig) or 27.6 MPa (4000 psig). The minimum bursting pressure for new hoseassemblies shall be 78.0 MPa (11 300 psig). For hose assemblies which have been pre-conditioned per3.1.2.5, 3.1.2.9, and 3.3.2
45、.9, the minimum bursting pressure shall be 70.0 MPa (10 145 psig). For hoseassemblies which have been pre-conditioned per 3.1.2.11 and 3.3.2.6, the minimum bursting pressure shall be65.5 MPa (9493 psig). For hose assemblies which have been pre-conditioned per 3.3.1.1, the minimumbursting pressure sh
46、all be 50.0 MPa (7250 psig).No more than 50% of the samples may have a burst location within 20 mm of the crimp ferrule.Table 7: Burst TestTest Requirement Pass CriteriaBurst 78.0 MPa(11 300 psig) Minimum burst pressureBurst (3.1.2.5, 3.1.2.9, 3.3.2.9) 70.0 MPa(10 145 psig) Minimum burst pressureBur
47、st (3.1.2.11, 3.3.2.6) 65.5 MPa(9493 psig) Minimum burst pressureBurst (3.3.1.1) 50.0 MPa(7250 psig) Minimum burst pressure3.1.2.3 Volumetric Expansion. See Table 8 thru Table 11.3.1.2.3.1 Test Procedure for Ambient Temperature Condition. Six assemblies crimped at nominal hosecompression shall be te
48、sted. Hose assemblies shall be tested to the requirements of GMW16837. Eachactuation cycle, as defined in GMW16837 shall consist of pressurization from 0 MPa (0 psig) to each of the fivemeasurement pressures, 1.0 MPa (145 psig), 2.8 MPa (400 psig), 6.9 MPa (1000 psig), 10.4 MPa (1508 psig)and 20.0 M
49、Pa (2920 psig).Volumetric expansion test methods equivalent to GMW16837 may be used to meet the requirements of thistest, upon the review and approval of the test method by the GM Materials Engineer issuing the EngineeringSource Approval to the GMW3056 specification.3.1.2.3.2 Acceptance Determination for Ambient Temperature Condition. The volumetric expansion at1.0 MPa shall be equal to or less than 0.16 cm3/m (0
