1、= = = 3535789 0274363 767 kks - i = COMMERCIAL STANDARD CS274-66 TFE-Fluorocarbon (Polytetrol fluoroethylene) Resin Sintered Thin Coatings for Dry Film Lubrication For sale by the Superintendent of Documents U.S. Government Printing Office, Washington, D.C., 20402 - Price 10 cents Provided by IHSNot
2、 for ResaleNo reproduction or networking permitted without license from IHS-,-,- W 3535789 0274362 bT3 US. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS Office of Product Standards EFFECTIVE DATE Having been passed through the regular procedures of the Office of Commodity Standards (now Office
3、 of Product Standards, Xatioiial Bureau of Standards) and approved by the acce tors hereinafter listed, this Commercial Standard is issued by the U.E. Department of Commerce, effective January 20,1966. JOHN T. COSXOR, Secretary. COMMERCIAL STANDARDS Commercial Standards are developed by manufacturer
4、s, distribu- tors, and users in cooperation with the Office of Product standards of the National Bureau of Standards. Their purpose is to establish uality criteria, standard methods of test, rating, certification, and Tabeling of manufactured commodities, and to provide uniform basis for fair compet
5、ition. The adoption and use of a Commercial Standard is voluntary. However, when reference to a Commercial Standard is made iii con- tracts, labels, invoices, or advertising literature, the provisions of the standard are enforceable through usual legal channels as a part of the sales contract. Comme
6、rcial Standards originate with the proponent industry. The sponsors may be manufact.urers, distributors, or users of the specific product. One of these three elements of industry submits to the Office of Product Standards the necessary data to be used as the basis for developing a standard of practi
7、ce. The Office by means of assembled conferences or letter referenda, or both, assists the sponsor group in arriving at a tentat.ive standard of practice and thereafter refers it to the other elements of the same industry for approval or for construc- tive criticism that will be helpful in making an
8、y necessary adjustments. The regular procedure of the Office assures continuous servicing of each Commercial Standard through review and revision whenever, in the opinion of the industry, changing conditions warrant such action. SIMPLIFIED PRACTICE RECOMMENDATIONS Under a similar procedure the Offic
9、e of Product Standards coop- erates wit.h industries in the establishment of Simplified Practice Rec- ommendations. Their purpose is to eliminate avoidable waste through the establishment of standards of practice for sizes, dimensions, vari- eties, or other characteristics of specific roducts; to si
10、mpli aging practices; and to establish simplged methods of per orming specific tasks. ? The initial printing of Commercial Standard CS274-86 was made possible through the cooperation of The Society of the Plastics Industry, Inc., in securing copies for its members. P303LEM HARD COPY Provided by IHSN
11、ot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. 3515789 O274163 53T , 1- 2788 Commercial Standard CS274-66 TFE-FLUOROCARBON (POLYTETRAFLUOROETHYLENE) RESIN SINTERED THIN COATINGS FOR DRY FILM LUBRICATION (Effective January 20,19661 i. PURPOSE 1.1 The purpose of th
12、is Cammercial Standard is to establish a na- tional standard of quality for the information and guidance of pro- ducers, distributors, and users; to promote understanding between buyers and sellers; to provide a basis for fair competition among producers; to gire the (3oiisumer confidence in the qua
13、lity of the product, and to provide means for identifying ooat.ings of polytetra- fluoroethyleiie (referred to herein as TFE-fluorocarbon resin coat- ings) produced in conformance with this st.andard. 2. SCOPE 2.1 This standard establishes t.lie requirements and methods of test for the material, thi
14、ckness, workmanship, and properties of TFE- fluorocarbon resin coatings 0.001 inch or less in *thickness for the pur- pose of dry film lubrication. Methods of marking and indicating compliance with this standard are included. 2.2 Coatings complying with this standard will have an inherent coefficien
15、t of kinetic friction of less than 0.1 when applied to suffi- ciently hard substrates and sintered nt a temperature in excess of 630“ F. (See Appendix A1.5) 3. REQUIREMENTS 3.1 Material.-The TFE-fluorocarbon coating shall be composed of materials suitable for roducing a finish to meet the requiremen
16、ts ing shall be free from burrs, pits, fins, and other surface defects detri- mental to the operation of the making system as a dry film lubricant. 3.2 Workmanship.-The coat.hig shall be uniform, free from cracks, sags, runs, heavy edges, and incomplete coverage, and shall be completely heat fused.
17、The surface of the coating shall ,be free of foreign inclusionsor entrapped debris. 3.3 Thickness.-The coating shall have a maximum t.hickiieSs of 0.001 inch when measured in accordance with 4.3.1. 3.4 Roughness.-The coatin roughness shall not exceed 90 micro- inches when measured in accor 3 ance wi
18、th 4.3.2. 3.5 Adhesion.-The coat.ing adhesion to the substrate shall be satis- factory as determined by the method described in 4.3.3. 3.6 Interfacial tension.-The minimum acceptable contact angles shall be greater than 90 for water, 81“ for methylene iodide, and 35“ for n-hexadecane. (Pure smooth T
19、FE exhibits 108O, 88O, and 46O re- 3 of this standard. The su L trate, prior to t.he application of the coat- _ PROSLEM tiARD COPY Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- W 3515787 0274164 476 W s ectively for these fluids.) Coatings failing
20、 to meet either of the coating shall be applied. The interfacial tension of the coating shall be determined by the met.hod described in 4.3.4. 3.7 Continuity.-The continuity of t,he coating shall be determined by the method described in 4.3.5. Cracks visible at a magnification of 20 x shall be cause
21、 for rejection. a g ove requirements shall be removed and replaced. KO corrective 4. METHODS OF TEST 4.1 Sampling.-Samples shall be taken at random from each lot. of TFE-coated items to determine its conformance with this standard. The tests described in 4.3 are nondest.ructive when performed on sat
22、isfactory TFE-coatings. Inspection.-The TFE-coated items shall be visually inspected to verify their compliance with the requirements specified in 3.2 of this standard. 4.3 Tests.- 4.3.1 Thickness.-The coating thickness when applied to flat mag- netic substrates shall be determined in several locati
23、ons on the coated specimen in accordance with the requirements of Method 6181 of Fed- eral Test Method Standard No, 141.l For nonmagnetic substrates a gage such as the “Dermitron” or equivalent, may be used? 4.3.2 Roughness,-The maximum surface roughness of the coated items shall be determined by vi
24、sual comparison with cornparison roughness specimens or with a Profilometer, Brush Surfindicator or equivalent, using three specimens. Failure of any specimen to meet the r uirement of 90 microinches maximum shall be cause for rejec- 4.3.3 Adhesion.-The adhesion of the coating to the substrate shall
25、 be determined on three specimens using a Shore Durometer Tester Type A instrument. The tester shall be placed on the coating of the sub- strate and ressed down firmly to force the spring-loaded flattened conical pro E e inward to the maximum load. The tester shall then be slid over the coating in t
26、he direction of the longer dimensions of the instrument. Visible ploughing or detachment of the coating from any specimen shall be cause for rejection of the lot. NOTE: Care should be exercised to avoid scratching the specimen. All feather edges on the probe of the instrument should be carefully rem
27、oved, if present. 4.2 tion 7 o the lot. ICopies of Federal Test Method Standard No. 141 Paint Varnish, Lac uer and Related Natcrlals * Methods of Inspection Sam ling an8 Testing, may be obtaqned. from the General Servies Administration Regin 3 Bedera1 Supply Service Buring Divislon. General Services
28、 Re onal Omce Building, Wahington, D.C at $3 per cops. 2 Available from therefore? the use of such coating is limited to substrate materials capable of withstanding such exposure. Low melting metals, solders and platings are a11 affected by the required thermal exposure. Copper and copper containing
29、 alloys are reactive at the required sintering temperature and therefore do not exhibit as good adhesion of TFE coatings as do ferrous metals. Also some metals may be degraded in mechanical properties by the metallurgical effects introduced by the thermal exposure. A1.3 Primer coatings.-The use of p
30、rimer coatings containing proprietary ingredients to improve adhesion and impede corrosion is optional. Such ingredients often react with contaminated substrate 6 to advantage where ot.her requirements B etermine their usage. Provided by IHSNot for ResaleNo reproduction or networking permitted witho
31、ut license from IHS-,-,-W 3515789 O274167 LB5 W _I_ 27P2 P3OEtEM HARD COPY I materials to produce undesirable staining of the sintered fhish. For example, fingerprints often produce brown staining of primer coats. However, under some conditions a random mottling of primer coatin s strate material wi
32、stli no other effect than that of appearance. Where color differences or stainin of top coats occur there should be a pre- sumption that either the kishing material lias deteriorated or that the nisli was applied to a contaminated surface. AL4 Surface roughness.-The surface roughness of thin TFE coa
33、tings is influenced by the roughness of the substrate and by the method of application. Surface roughness of the substrate lias an effect on the adhesion of the TFE film, the durability of the film as a lubricant and on the coefficient of friction. It lias been determined that o timum performance of
34、 lubricating TFE films is obtained blasted to a siiTface roughness not exceefing 90 microinches. $he use of rougher finishes will decrease life expectancy of the lubricating film and the use of uery smooth glossy finishes will increase th Co. Plastics Department, Wilmington, Del. Dynamatic Division,
35、 Eaton Manufacturing Co., Kenosha, Wis. Eastern Industries Division, Laboratory for Electronics, Inc., Hamden, Conn. Edgerton, Germeshausen 8: Grier, Inc., Bedford, Nass. Enflo Corporation, Maple Shade, N.J. Ethylene Corporation, Murray Hill, N.J. Falls Hollow Staybolt Co., Metal Coating Division, C
36、uyahoga Falls, Ohio Fluoro-Plastics, Inc., Philadelphia, Pa. Fluorocarbon Company, The, Palo Alto, Calif. Froehling however, such signature indicates an intention to follow the standard, where practicable, in the production, distri- bution, or consumption of the article in question. 3. The Departmen
37、ts responsi1ity.-The major function, performed by the Department of Commerce in the voluntary establishment of Commercial Standards on a nationwide basis is fourfold : First, to act as an unbiased coordi- nator to bring all interested parties together for the mutually satisfactory adjustment of trad
38、e standards ; second, to supply such assistance and advice as past experience with similar programs may suggest ; third, to canvass and record the extent of acceptance and adherence to the standard on the part of producers, distributors, and users ; and fourth, after acceptance, to publish the stand
39、ard for the information and guidance of buyers and sellers of the commodity. 4. Anmuncmt.-When the standard has been endorsed by a satisfactory majority of production or consumption in the absence of active, valid opposition, the success of the project is announced. If, however, in the opinion of th
40、e standing committee or of the Department of Commerce, the support of any standard is inadequate, the right is reserved to withhold publication. U.S. GOVERHHEXT PRINTING OFFICL:19EE -. 2795 PROL.EM HARD COPY Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
