1、 WORLDWIDE ENGINEERING STANDARDS General Specification GMW16883 Performance Requirements for Engine Plastic Parts Copyright 2012 General Motors Company All Rights Reserved November 2012 Originating Department: North American Engineering Standards Page 1 of 7 1 Introduction Note: Nothing in this stan
2、dard supercedes applicable laws and regulations. Note: In the event of conflict between the English and domestic language, the English language shall take precedence. 1.1 Scope. This standard includes the performance requirements of plastic parts installed directly in an engine environment whereby t
3、he applied mechanical and thermal loads are typical of those experienced in both light and heavy duty over the road automotive applications. The parts may be functional within themselves or they may be a subassembly of, or attached to, metallic, or non-metallic functional parts. Note: Additional req
4、uirements for coated or painted plastic parts (e.g., emblems, painted engine covers) are given in the relevant performance specifications; not by this specification. Note: All materials used in parts or components in contact with the air of the interior compartment must additionally conform to the i
5、nterior requirements as specified in GMW14444, Code E. 1.2 Mission/Theme. This standard provides the standard material performance requirements for engineered plastic parts for use on an engine and/or near the exhaust system. Typical applications on an engine include cam covers, oil pans, front cove
6、r rear covers, etc. This specification is intended to provide functional guidelines that enable/support the manufacturing process and control plan validation. It is not intended to specify validation requirements as they relate to product performance. 1.3 Classification. The operating characteristic
7、s of parts covered by this standard are operating continuous temperature of -40 C up to a maximum continuous temperature according to Table 1. Peak temperatures can exceed the maximum continuous temperature by 20 C. These peaks can make up 60 h in the lifetime of the vehicle. Based on the maximum co
8、ntinuous temperature in installed position on the engine or near the exhaust system, the parts are identified by Class 1 to Class 4 according to Table 1. Unless otherwise specified, all engine mounted components are expected to meet Class 3 environmental requirements with the exception of those loca
9、ted in close proximity to the engine exhaust. Table 1: Operating Temperatures Class Maximum Continuous Temperature in Degrees Celsius (C) Peak Temperature in Degrees Celsius (C) 1 +110 +130 2 +110 to +130 +130 to +150 3 +130 to +150 +150 to +170 4 +150 +165 2 References Note: Only the latest approve
10、d standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ANP 255 ISO 1817 SAE J1681 Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WOR
11、LDWIDE ENGINEERING STANDARDS GMW16883 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 2 of 7 2.2 GM Standards/Specifications. 9985010 B 040 0218 B 040 2095 GMW14444 9985670 B 040 1065 B 040 2098 GMW14914 9985809 B 040 1068 GME L0004 GMW15827 9985930 B 040 1073 GMW3059 GM
12、W16444 9986117 B 040 1095 GMW3155 HN1992 9986121 B 040 1098 GMW3221 HN2464 9986153 B 040 1370 GMW3356 L 000 0102 9986231 B 040 1990 GMW3420 L 000 0555 9986284 B 040 2030 GMW14093 L 000 0556 9986298 B 040 2071 GMW14334 2.3 Additional References. API CH-4 (contact Materials Engineer for further inform
13、ation) API CI-4 (contact Materials Engineer for further information) GM P/N Canada 89021807 GM P/N US 89021806 MATSPC (GM Materials File Database) 3 Test Preparation and Evaluation 3.1 Resources. 3.1.1 Calibration. The test facilities and equipment shall be in good working order and shall have a val
14、id calibration label. 3.1.2 Alternatives. Alternative test facilities and equipment may also be used. However, all measuring variables as specified in this standard shall be determined correctly with respect to their physical definition. 3.1.3 Facilities. Not applicable. 3.1.4 Equipment. Not applica
15、ble. 3.1.5 Test Vehicle/Test Piece. Unless otherwise specified in the relevant test method for the property concerned, either the complete component or a section therefrom shall be used for test pieces. Unless otherwise specified in the appropriate test methods, at least one test piece shall be test
16、ed. 3.1.5.1 Test pieces shall not be tested within 72 h of manufacture. 3.1.5.2 Conditioning. Unless otherwise stated in respective test procedures, all samples shall be conditioned prior to each requirement test to GMW3221, Code A. 3.1.6 Test Time. Conforming to the relevant test procedures. 3.1.7
17、Test Required Information. Conforming to the relevant test procedures. 3.1.8 Personnel/Skills. Not applicable. 3.2 Preparation. Conforming to the relevant test procedures. 3.3 Conditions. 3.3.1 Environmental Conditions. Conforming to the relevant test procedures. 3.3.2 Test Conditions. Deviations fr
18、om the requirements of this standard shall have been agreed upon. Such requirements shall be specified on component drawings, test certificates, reports, etc. 3.4 Instructions. Not applicable. 3.5 Data. Not applicable. 3.6 Safety. This standard may involve hazardous materials, operations, and equipm
19、ent. This standard does not propose to address all the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Copyright General Motors
20、Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW16883 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 3 of 7 3.7 Documentation. Sampl
21、es of components or material released to this standard shall be tested for conformity with the requirements of this standard and approved by the responsible GM department prior to the start of delivery of production level components or materials. Any change to the component or material, e.g., design
22、, function, properties, manufacturing process and/or location of manufacture requires a new release of the product. It is the sole responsibility of the supplier to provide the customer, unsolicited, with documentation of any change or modification to the product/process, and to apply for a new rele
23、ase. If not otherwise agreed to, the entire verification test shall be repeated and documented by the supplier prior to start of delivery of the modified or changed product. In some cases, a shorter test can be agreed to between the responsible GM department and the supplier. 3.7.1 Test Results. 3.7
24、.1.1 Test Report. The test report shall have the same outline and numbering as this test specification. 3.7.2 Deviation from Standard. Deviation from the requirements of this standard shall have been agreed upon. Such requirements shall be specified on the component drawings, test certificates, repo
25、rts, etc. 4 Requirements and Procedure 4.1 Raw Material Specification Conformance. The components of the assembly must be made from materials which meet the individual material specifications shown on the engineering drawing, in addition to meeting the requirements of this performance specification.
26、 Engineering qualification of an approved source is required for the material specification called out on the part drawing/math data. Only sources listed in the GM Materials File (MATSPC Database) under the material specification number per drawing callout/math data have been qualified by engineerin
27、g as meeting the requirements of this material specification. 4.2 Regrind. The percent regrind allowed per part shall not exceed the numeric value following the suffix RE-symbol. If Home Scrap regrind (scrap that is reused back into the same part) is the only type to be specified for use, the letter
28、s HS should follow the numeric regrind value. The use of regrind must not preclude the part from meeting the other specified characteristics of part performance. Furthermore, in any case, The maximum regrind content shall be limited to the percent that was validated and submitted for Production Part
29、 Approval Process (PPAP). The type of regrind must be of the same material that was validated and submitted for PPAP. The regrind must be clean, dry, and free of contamination. Examples: RE10 = 10% maximum regrind RE20HS = 20% maximum Home Scrap regrind Note: If regrind is to be used, all test parts
30、 must be manufactured with the maximum amount of regrind the supplier intends to use. 4.2.1 When this specification and RE suffix does not appear on the part print, no regrind is approved for use. 4.2.2 Not painted, laminated or plated regrind may be used without the written approval of the GM Mater
31、ials Engineering Department. 4.3 Resistance to Temperature - Humidity Cycle. Test pieces shall be assembled to jigs or forms so as to simulate as closely as possible actual service under nominal build conditions. The complete test assembly shall then be subjected to the following test cycle. Final p
32、art testing to GMW3155 is required. 4.3.1 This cycle shall be performed one time using the temperatures from Table 2. 24 h 1 h at Temperature A 4 h 0.5 h at Temperature C 72 h 1 h at Temperature B 24 h 1 h at +40 C 3 C and 93% 5% relative humidity (RH) 4 h 0.5 h at Temperature C 24 h 1 h at +22 C 3
33、C 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 GMW16883 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 4 of
34、 7 Note: Humidity paragraph required for moisture containing materials only (e.g., Polyamide and Polyester). If there are any questions concerning the material, contact the responsible GM Materials Engineer. Table 2: Test Temperatures Temperature in Degrees Celsius (C) Class A B C Class 1 +130 +110
35、-40 Class 2 +150 +130 -40 Class 3 +170 +150 -40 Class 4 Specially defined. -40 Note: Class 4 Temperatures A and B shall be defined on the part drawing/math data. 4.3.2 Requirement. Test pieces shall show no cracking, crazing, appreciable color changes, discoloration, cloudiness, blistering, objectio
36、nable shrinkage, and deformation, loss of adhesion to the substrate between layers of the composite or other changes detrimental to serviceability. Test pieces shall comply with the dimensions specified on the drawing after completion of the test. 4.4 Test for exposure to elevated temperatures while
37、 in transport to a GM assembly facility. Test pieces shall be assembled to jigs or forms so as to simulate as closely as possible actual shipping conditions of the part. They are not to be physically constrained anything more than that experienced while shipping. A minimum of one piece per mold cavi
38、ty is to be tested. The complete test assembly shall then be subjected to the following test cycle. 4.4.1 This cycle shall be performed one time with the part soaked at 100 C for 24 h. 4.4.2 Requirement. The test piece shall not exhibit changes that would be considered detrimental to engine assembly
39、 and handling. Contact Material Engineer/Design Responsible Engineer for details. Test pieces shall comply with the dimensions specified on the drawing after completion of the test and inspected at room temperature. 4.5 Resistance of Material to Heat Ageing/Oxidation Stability. Note: For Polypropyle
40、ne base materials only. All nylon materials are required to be tested at higher temperatures. See specific nylon specifications for details. 4.5.1 Parts located in the engine compartment or near the exhaust system require additional, particularly effective, stabilization to avoid the degradation by
41、oxidation of the material in hot air. Test pieces shall be exposed for 336 h 2 h for 14 days in an air circulating oven operating at +150 C 3 C. 4.5.2 Requirement. No visible indication of local discoloration and/or brittleness by material degradation. 4.6 Impact Resistance (GMW14093). Note: For par
42、ts with large plain areas, e.g., oil pans, test shall be conducted on components. If no specific area of the part is assigned on the drawing to meet the impact requirements, the part shall be tested in the thinnest section and meet these requirements. Impact resistance to GMW14093 - 3/2.5 J minimum.
43、 For components exposed to road hazard impact XX/YY J minimum, ask Design Responsible Engineer/Material Engineer for clarification. In the as-received condition. After resistance to 4.3 Temperature - Humidity Cycle. 4.7 Resistance to Fluids. All materials shall be resistant to the media they contact
44、, such as aliphatic and aromatic hydrocarbons, fuels, lubricants, oils, greases and alcohols at their places of use. Table 3 defines typical requirements for such resistance to fluids which apply or do not apply based on installation position. The part drawing/math data shall call out the applicable
45、 items. Additional fluids, if applicable, shall be noted on the part drawing/math data. 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 GMW1
46、6883 Copyright 2012 General Motors Company All Rights Reserved November 2012 Page 5 of 7 4.7.1 Standard Engine Compartment Resistance. If (standard) is specified for resistance to fluids, the following fluids will be tested: A, F, H, K, M, N, and P. Note: Other regional Original Equipment Manufactur
47、er (OEM) initial fill equivalent liquids may be used per the discretion of the approving GM Engineer. Part shall be resistant to the liquids of the region to which the part is delivered. 4.7.2 Fluids A, B, E to M, and O to Q. Test per GMW14334 - X - Rating 4, 24 h immersion time. 4.7.3 Fluids C and
48、N. Test per GMW14334 - B - Rating 4. 4.7.4 Alternative test method for parts having an extra protection coating on the side facing the engine compartment: 5 mL of the respective liquid shall be put on the side facing the engine compartment over 25 cm2. Test temperature, test time and evaluation as d
49、efined in 4.7.2 and 4.7.3 respectively. 4.7.5 Requirement. There shall be no color change, loss of bond, material degradation, or tackiness following the test. 4.8 Knit Line Strength. All injection molded parts that include features where there is a separation and rejoining of the material flow front during the molding process that results in the formation of a material knit line, shall be evalu
