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1、PPS60.8.104 Issued: 28-May-99PRODUCT PERFORMANCE STANDARDFile No. 62-0 RECORD OF CHANGES Rev. Ltr.PCN No.Date IssuedPage(s) AffectedRev. Ltr.PCN No.Date IssuedPage(s) Affected AC BD Written: T. ChristensenApproved: W. Pagac THE INFORMATION CONTAINED IN THIS DOCUMENT IS CONFIDENTIAL AND THE SOLE PROP
2、ERTY OF SNAP-ON INCORPORATED, AND MAY NOT BE REPRODUCED WITHOUT THE WRITTEN PERMISSION OF SNAP-ON INCORPORATED. SNAP-ON INCORPORATEDPage 1 of 6PRODUCT STANDARDS ZINC PLATING STANDARD ZINC PLATINGPPS60.8.104 Issued: 28-May-99PRODUCT PERFORMANCE STANDARDFile No. 62-0 SNAP-ON INCORPORATEDPage 2 of 6PRO
3、DUCT STANDARDS TABLE OF CONTENTS SectionPage 1.0 SCOPE.3 2.0 DEFINITIONS AND CLASSIFICATIONS.3 3.0 PRODUCT EVALUATION .3 3.1 Requirements.3 3.1.1 Plating Thickness.3 3.1.2 Appearance.3 3.1.3 Chromate Conversion Coatings.4 3.1.4 Product Designation.4 3.1.5 Workmanship.4 3.1.6 Tolerance.4 3.1.7 Adhesi
4、on.4 3.1.8 Corrosion Resistance .5 3.1.9 Hydrogen Embrittlement.6 3.2 Testing.6 3.2.1 Corrosion Resistance Test.6 3.2.2 Thickness .6 3.2.3 Adhesion.6 4.0 RELATED DOCUMENTS.6 ZINC PLATINGPPS60.8.104 Issued: 28-May-99PRODUCT PERFORMANCE STANDARDFile No. 62-0 SNAP-ON INCORPORATEDPage 3 of 6PRODUCT STAN
5、DARDS 1.0 SCOPE This standard covers the electrodeposition of zinc plate on metal parts for corrosion protection. It is to be used as a corporate controlling document to: (1) insure consistent performance levels, (2) provide a means by which uniform coating levels may be evaluated, and (3) assist Sn
6、ap-on manufacturing plants and suppliers applying this type of coating. All zinc plated parts are subject to the performance levels contained herein. 2.0 DEFINITIONS AND CLASSIFICATIONS Service Condition Number Indicates the severity of the intended use in accordance with SAE J207. Significant Surfa
7、ces - Unless otherwise specified, significant surfaces are all surfaces that can be touched by a sphere 19mm (0.75”) in diameter. Areas having a minimum thickness to be met shall be designated on the applicable drawing or by a suitably marked sample. 3.0PRODUCT EVALUATION 3.1Requirements 3.1.1Platin
8、g Thickness The zinc plating shall be provided in four thickness classes as follows: ClassService ConditionThickness (inches) Minimum 4SC-1 (very severe)0.0010 3SC-2 (severe)0.0005 2SC-3 (moderate)0.0003 1SC-4 (mild)0.0002 Note: (1) Thickness in excess of 0.0003 may require reduced pitch and/or majo
9、r diameters on threaded fasteners. (2)Thickness applies only too significant surfaces specified in section 3.1.2 3.1.2Appearance The appearance and color shall be as agreed upon between the purchaser and supplier using approved color standards when available. Zinc conversion coatings listed herein r
10、equire a clean commercial finish. The range of color, iridescence, opaqueness, and sheen are normally not critical unless otherwise specified by the purchaser. In the case of bright zinc plus clear finish listed herein, a clear bright appearance (also referred to as colorless) is required. ZINC PLAT
11、INGPPS60.8.104 Issued: 28-May-99PRODUCT PERFORMANCE STANDARDFile No. 62-0 SNAP-ON INCORPORATEDPage 4 of 6PRODUCT STANDARDS The zinc plating shall have one of the finishes defined as follows: TypeDescriptionFinish IAs plated without supplementary treatmentSemi-bright IIWith colored chromate conversio
12、n coatingsSemi-bright or bright IIIWith colorless chromate conversion coatingsSemi-bright or bright IVWith phosphate conversion coatingsDull 3.1.3Chromate Conversion Coatings Chromate conversion coatings are applied in various colors. The color may serve as a code or identification, besides giving c
13、orrosive protection against white corrosion products. Additional colors may be obtained by using a dye over the chromate coating. The following colors are available and shall be specified by number on the product drawing. (see section 3.1.4) -1 Transparent (Clear)-3 Yellow/Gold -2 Black-4 Olive Drab
14、 (Green) 3.1.4Product Designation All component drawings shall include the following information for a zinc plate finish specification. example:zinc plate per PPS60.8.104-1C2 PPS60.8.104-1C2Definition Thickness class (e.g. C2= Class 2; 0.0003 thickness Chromate coating color (-1 = Transparent(clear)
15、 Zinc plating standard number 3.1.5Workmanship The plating shall be smooth, continuous, uniform in appearance, and not coarse or crystalline. It shall be free from pin holes, porosity, pits, blisters, nodules and other harmful defects. Coverage shall be complete except in deep or very small diameter
16、 holes and internal threads where a deposit cannot be obtained under normal plating conditions without auxiliary electrodes. 3.1.6Tolerance Tolerances specified on drawings are for final dimensions unless otherwise indicated. When plating build-up on parts exceeds normal allowances, special allowanc
17、e in the part dimensions before plating must be made by manufacturing. 3.1.7Adhesion Coatings shall have good adhesion and show no tendencies of flaking, peeling, or brittleness when examined in accordance with Section 3.2.3, or as tested per ASTM B571. ZINC PLATINGPPS60.8.104 Issued: 28-May-99PRODU
18、CT PERFORMANCE STANDARDFile No. 62-0 SNAP-ON INCORPORATEDPage 5 of 6PRODUCT STANDARDS 3.1.8Corrosion Resistance Sample parts or test panels shall be exposed to salt spray in accordance with section 3.2.1 for the time shown in Table 3.1.8. Zinc coatings shall show no corrosion products of the base me
19、tal exhibited by red rust. The appearance of six or more red rust spots larger than 1/16 (0.06)inch diameter per one square foot shall be considered unacceptable. One or more red rust spot larger than 1/16 (0.06) inch diameter on an area of 1/6 square foot on significant surfaces visible to the unai
20、ded eye shall be considered unacceptable. Supplementary protection from corrosion can be derived from the addition of a chromate or dichromate coating. Four basic coatings are available. Each provides additional protection beyond a zinc-only plated surface. This period of protection is added to the
21、time period as specified in Table 3.1.8 for the thickness of the zinc chosen. Zinc plating with any of these supplementary treatments shall protect against the formation of white corrosion products (the breakdown of the chromate or dichromate) for the additional time period specified in Table 3.1.8.
22、 Table 3.1.8 Corrosion Resistance Requirements Resistance to Neutral Salt Spray Zinc Plating Thickness (inches) Hours to Base Metal Corrosion Hours to White Corrosion of Zinc Coating MinimumMinimumMinimum Coverage only coatingNot required 0.000236 0.000356Zinc 0.000596 0.00024812 0.00036812 Zinc and
23、 Clear Chromate 0.000510812 0.00026024 0.00038024 Zinc and Black Chromate 0.000512024 0.000213296 0.000315296 Zinc and Yellow/Gold Dichromate 0.000519296 0.0002186150 0.0003206150 Zinc and Olive Drab Chromate 0.0005246150 ZINC PLATINGPPS60.8.104 Issued: 28-May-99PRODUCT PERFORMANCE STANDARDFile No.
24、62-0 SNAP-ON INCORPORATEDPage 6 of 6PRODUCT STANDARDS 3.1.9Hydrogen Embrittlement All parts hardened to Rc 25 or higher, case hardened to any depth by any process and posing a possibility of embrittlement shall be heated within one (1) hour maximum after plating at 375- 400 degrees F for four (4) ho
25、urs to remove possible hydrogen embrittlement. This heating shall precede any supplementary treatment such as chromate conversion and shall not affect the original heat treatment of the component. The application or requirement of embrittlement relief shall be specified on the product drawing. 3.2Te
26、sting The following tests shall be performed by Snap-on manufacturing facilities, suppliers producing zinc plated components, or qualified independent test laboratories. Adequate safeguards for personnel and property shall be employed in conducting all tests. 3.2.1Corrosion Resistance Test Determina
27、tion of corrosion resistance shall be in accordance with ASTM B117. Samples shall be tested to meet the time stated in Section 3.1.7. To secure uniformity of results, Types II and III supplementary coatings should be aged at room temperature (72F 10) for 24 hours prior to salt spray. If the size and
28、 shape of the part to be tested would preclude accurate or interpretable results of this test, a test panel can be used. The test panel shall be of the same material and surface finish of the part to be tested. The test panel shall also be subjected to the same pre- plating, electroplating, and post
29、 plating cycle as the part they represent. 3.2.2Thickness Tests for coating thickness shall be conducted per ASTM B504, or one of equivalent accuracy. In cases of dispute, the referee method shall be metallographic examination. 3.2.3Adhesion Test for coating adhesion shall be conducted per ASTM B571
30、. The evaluation of adhesion can be conducted by selecting any of the tests specified in ASTM B571 unless otherwise specified on the product drawing or purchase agreement. There shall be no evidence of flaking or peeling of the coating from the substrate. 4.0 RELATED DOCUMENTS The following document
31、s were used to form a part of this specification: ASTM A 164 Electrodeposited Coatings of Zinc on Steel. ASTM A 386 Salt Spray (Fog) Testing. ASTM B 201 Recommended Practice for Testing Chromate Coatings on Zinc and Cadmium Surfaces. ASTM B 322 Recommended Practice for Cleaning Metals Prior to Electroplating. ASTM B 504 Measurement of Thickness of Metallic Coatings by the Coulometric Method. ASTM B571 Test for Adhesion of Metallic Coatings. ASTM B 633 Electrodeposited Coatings of Zinc on Iron and Steel.