1、 ENGINEERING MATERIAL SPECIFICATIONDate Action Revisions 2006 09 13 Revised Paragraph 3.4.3 added 16 hour soak A. Cockman 2004 09 20 Activated A. Cockman, J Luther Printed copies are uncontrolled Copyright 2006, Ford Global Technologies, LLC Page 1 of 4 CORROSION PROTECTIVE COATING, SILVER/SILVER GR
2、AY WSS-M21P45-A1 CORROSION PROTECTIVE COATING, BLACK WSS-M21P45-A2 1. SCOPE The materials defined by these specifications are corrosion protective coatings over steel. These coating systems provide corrosion protection and color and are intended for Spring Band Hoseclamps. These coatings are free of
3、 chromium, nickel, lead and cadmium. 2. APPLICATION These specifications were released originally for materials used for corrosion protective coatings over steel. They are intended for Constant Tension Spring Band Hoseclamps where a high level of corrosion protection is required. 2.1 SERVICE TEMPERA
4、TURE The maximum continuous service temperature resistance is 200 C. 3. REQUIREMENTS Material specification requirements are to be used for initial qualification of materials. 3.1 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must conform to the Companys Standa
5、rd Requirements For Production Materials (WSS-M99P1111-A). 3.2 LICENSEE APPLICATOR QUALITY REQUIREMENTS Applicators must follow coating manufacturer procedures and recommendations for chemical usage, equipment and processing. 3.3 MATERIAL PERFORMANCE 3.3.1 Raw Material Storage Stability The material
6、 must be capable of being stored at 23 +/- 2 C for 60 days without detrimental effect to the performance of the coated parts. 3.3.2 Cleaning Prior to coating, the parts shall be free of oil, scale, and similar foreign materials. The cleaning process shall have no detrimental effect on the substrate,
7、 including freedom from embrittlement. ENGINEERING MATERIAL SPECIFICATIONWSS-M21P45-A1/A2Printed copies are uncontrolled Copyright 2006, Ford Global Technologies, LLC Page 2 of 4 3.3.3 Curing These coatings are typically cured at 200 to 220 C. Alternative cure temperatures may be used provided mecha
8、nical properties of the clamp are not affected. Parts must be sufficiently cured at the time of packing to withstand normal handling and shipping without marring. 3.3.4 Appearance A1 Uniform silver/silver gray A2 Uniform black The coating shall be uniform in color and free from discontinuities when
9、viewed without magnification. Where part grounding is required to apply the finish the grounding point shall be on the tang of the clamp and shall not impact clamp performance. 3.3.5 Storage Life Parts supplied shall still meet the specific requirements of this specification 6 months after receipt b
10、y Ford when stored at 5 to 28 C with no direct heat or sunlight. 3.4 ADHESION 3.4.1 The cured coating shall withstand normal handling, storage and installation without flaking or peeling or other loss of adhesion. 3.4.2 Parts heated to 120 C for 60 minutes shall not exhibit blistering, peeling, flak
11、ing or coating which can be removed by a filament type tape, such as 3M No. 898-2. The testing of coating quality by salt spray and/or determination of coating thickness will be performed on parts passing the adhesion test. 3.4.3 Hoseclamps may be used in Pre-Opened, Pre-Positioned (POPP) applicatio
12、ns; these are applications where the hoseclamp is glued to the hose to assist assembly. After a 16 hour soak at a relative humidity of 95% min. the adhesion of the coating shall be sufficient to withstand a load of 34Kg applied to the tangs in a horizontal or radial direction and shall meet the foll
13、owing requirements: 3.4.3.1 There shall be no separation of the coating and substrate. 3.4.3.2 There shall be no separation between coating layers. 3.5 RESISTANCE PROPERTIES PRECONDITIONING Prior to performing the restistance tests, the finished clamps shall undergo the following procedure to simula
14、te handling and transportation damage: a) Fill a cardboard box full of clamps to be tested. (No larger than 250X250X250) b) Secure the box thoroughly to prevent it from breaking open. c) Slowly slide the box off of a surface 0.75 meters onto the floor. d) Repeat step c 30 times, alternating between
15、top, side and bottom of box. ENGINEERING MATERIAL SPECIFICATIONWSS-M21P45-A1/A2Printed copies are uncontrolled Copyright 2006, Ford Global Technologies, LLC Page 3 of 4 3.5.1 Sodium Hypochlorite Resistance The following procedure is used for new coating approvals or for in-process testing of approve
16、d coatings. New coating approvals shall use a minimum sample size of 30 clamps. After coating clamps of sizes Dn41 with the specified coating, thirty clamps shall be assembled on a PVC plastic mandrel 0.2 to 0.3 mm smaller than the full open diameter. The assembly shall be immersed in 2000 ml +/- 50
17、 ml of 4.95 - 5.05% sodium hypochlorite solution at 21 +/- 3 C, there shall be no evidence of cracking after 28 hours immersion. The Sodium Hypochlorite SCC Test Solution shall be assayed within 72 hours prior to test per the following procedure adapted from US Pharmacopeia*. Weigh accurately, in gl
18、ass flask 10 g of Sodium Hypochlorite SCC Test Solution, and dilute with 40 ml water. Add 0.4 g potassium iodide and 2 ml 6 N acetic acid, titrate the liberated iodine with 0.010 N sodium thiosulfate, adding 1 ml of starch TS as the endpoint is approached. Note, the solution is dark with a clear end
19、point, so a white background is required for an accurate end point determination. Perform a blank determination, and make any necessary correction. Each ml of 0.010 N sodium thiosulfate is equivalent to 0.3722 mg of NaOCl. *US Pharmacopeia analysis is for 4 to 6% NaOCl and has been adjusted for this
20、 dilute analysis. 3.5.2 Corrosion Resistance (FLTM BI 123-01) Hoseclamps coated to these specifications shall meet the General Requirements of WX100. Hose clamps shall be assembled on a PVC plastic mandrel 0.2 to 0.3 mm smaller than the full open diameter and shall be tested in accordance with FLTM
21、BI 123-01. The following requirements shall be met: 3.5.2.1 Hoseclamps shall be free of corrosion (equivalent to ASTM B 610 rating 6 or better) after 10 cycles. Corrosion due to touch marks on the clamp ears shall be excluded from the evaluation. 3.5.2.2 Hoseclamps shall meet the minimum clamp load
22、requirements as specified in WK902 after 40 cycles. 3.5.3 Water Resistance (FLTM BI 104-01) Shall not blister or show any signs of red rust when subjected to immersion in water for 240 hours. ENGINEERING MATERIAL SPECIFICATIONWSS-M21P45-A1/A2Printed copies are uncontrolled Copyright 2006, Ford Globa
23、l Technologies, LLC Page 4 of 4 3.5.4 Gasoline Resistance Shall not blister or show any signs of softening or dulling when subjected to immersion in current factory fill gasoline for 24 hours at 23 +/- 2 C. 3.5.5 Hot Oil Resistance Shall not blister or show any signs of softening or dulling when sub
24、jected to immersion in engine oil (SAE 10W30 per WSE-M2C903-A2 or equiv.) for 24 hours at 66 +/- 3 C. 3.5.6 Ethylene Glycol Resistance Shall not blister or show any signs of softening or dulling when subjected to immersion in a 50% solution of water and long life coolant concentrate (WSE-M97B44-B or
25、 equivalent) for 24 hours at 23 +/- 2 C. 3.5.7 Brake Fluid Resistance Shall not blister or show any signs of softening or dulling when subjected to immersion in currently approved brake fluid for 24 hours at 23 +/- 2 C. 3.5.8 Power Steering/Transmission Fluid Shall not blister or show any signs of s
26、oftening or dulling when subjected to immersion in current factory fill power steering and transmission fluid for 24 hours at 66 +/- 3 C. 3.6 COATING THICKNESS Because of the intended use on Constant Tension Spring Band Hoseclamps the coating thickness is not a significant requirement. However the c
27、oating thickness shall not inhibit other performance requirements of this specification or the installation or function of the hoseclamp. 3.7 FINISH FRICTION Finishes to these specifications shall meet the Torque/Clamping Force Performance Requirements of WZ 101 (Test Program B). Note: While WZ 101
28、is specifically for threaded fasteners, finish friction is important to the functional performance of hoseclamps to prevent hose bunching under the clamp. The coefficient of total friction (tot) of the top coat(s) shall not exceed 0.18. 4. GENERAL INFORMATION The information given below is provided
29、for clarification and assistance in meeting the requirements of these specifications. 4.1 CORROSION RESISTANCE (SAE/USCAR-1) Hoseclamps tested and evaluated in accordance with SAE/USCAR-1, typically pass a minimum of 120 hours without non-ferrous (white) corrosion and 480 hours without ferrous (red) corrosion.
