MSS SP-98-2015 Protective Coatings for the Interior of Valves Hydrants and Fittings.pdf

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1、 MSS SP-98-2015 Protective Coatings for the Interior of Valves, Hydrants, and Fittings Standard Practice Developed and Approved by the Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. 127 Park Street, NE Vienna, Virginia 22180-4602 Phone: (703) 281-6613 Fax: (703) 281-6

2、671 E-mail: standardsmsshq.org www.msshq.org MSS STANDARD PRACTICE SP-98i This MSS Standard Practice was developed under the consensus of the MSS Technical Committee 112 and the MSS Coordinating Committee. The content of this Standard Practice is the resulting efforts of competent and experienced vo

3、lunteers to provide an effective, clear, and non-exclusive standard that will benefit the industry as a whole. This MSS Standard Practice describes minimal requirements and is intended as a basis for common practice by the manufacturer, the user, and the general public. The existence of an MSS Stand

4、ard Practice does not in itself preclude the manufacture, sale, or use of products not conforming to the Standard Practice. Mandatory conformance to this Standard Practice is established only by reference in other documents such as a code, specification, sales contract, or public law, as applicable.

5、 MSS has no power, nor does it undertake, to enforce or certify compliance with this document. Any certification or other statement of compliance with the requirements of this Standard Practice shall not be attributable to MSS and is solely the responsibility of the certifier or maker of the stateme

6、nt. “Unless indicated otherwise within this MSS Standard Practice, other standards documents referenced to herein are identified by the date of issue that was applicable to this Standard Practice at the date of approval of this MSS Standard Practice (see Annex B). This Standard Practice shall remain

7、 silent on the validity of those other standards of prior or subsequent dates of issue even though applicable provisions may not have changed.” By publication of this Standard Practice, no position is taken with respect to the validity of any potential claim(s) or of any patent rights in connection

8、therewith. MSS shall not be held responsible for identifying any patent rights. Users are expressly advised that determination of patent rights and the risk of infringement of such rights are entirely their responsibility. In this Standard Practice, all text, notes, annexes, tables, figures, and ref

9、erences are construed to be essential to the understanding of the message of the standard, and are considered normative unless indicated as “supplemental”. All appendices, if included, that appear in this document are construed as “supplemental”. Note that supplemental information does not include m

10、andatory requirements. U.S. customary units in this Standard Practice are the standard; the SI (metric) units are for reference only. This Standard Practice has been substantially revised from the previous 2012 edition. It is suggested that if the user is interested in knowing what changes have been

11、 made, that direct page by page comparison should be made of this document. Non-toleranced dimensions in this Standard Practice are nominal unless otherwise specified. Excerpts of this Standard Practice may be quoted with permission. Credit lines should read Extracted from MSS SP-98-2015 with permis

12、sion of the publisher, Manufacturers Standardization Society of the Valve and Fittings Industry. Reproduction and/or electronic transmission or dissemination is prohibited under copyright convention unless written permission is granted by the Manufacturers Standardization Society of the Valve and Fi

13、ttings Industry Inc. All rights reserved. Originally Approved: 1987 Originally Published: June 1987 Current Edition Approved: April 2015 Current Edition Published: July 2015 MSS is a registered trademark of Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Copyright , 20

14、15 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.A. MSS STANDARD PRACTICE SP-98ii TABLE OF CONTENTS SECTION PAGE 1 SCOPE 1 2 DEFINITIONS . 1 3 AFFIDAVIT OF COMPLIANCE 2 4 COATINGS FOR DRINKING WATER SERVICE 2 5 SURFACE PREPARATION 2 6 COATING APPLIC

15、ATION . 2 7 COATING SYSTEM QUALIFICATION . 3 8 QUALIFICATION TESTING . 3 9 PRODUCTION TESTING . 4 10 SPECIAL TESTING 4 11 INSPECTION AND REJECTION . 4 12 SHIPPING, HANDLING, AND STORAGE PRECAUTIONS . 4 ANNEX A Holiday Testing Equipment and Procedures 5 B Referenced Standards and Applicable Dates 6 M

16、SS STANDARD PRACTICE SP-981 1. SCOPE 1.1 This Standard Practice covers the material, application, and performance requirements for liquid or powder interior coatings for valves, hydrants, and fittings. In addition, this Standard Practice covers equipment used to conduct holiday tests on coatings. Th

17、ese coatings are applied to interior ferrous surfaces of valves, hydrants, and fittings intended for use in water, drinking water, or reclaimed and wastewater systems where corrosion protection is specified. 1.2 Where it is necessary, because of the application process or purchase requirements, the

18、coating may also be specified for exterior use, with recognition that performance parameters may vary from those specified for interior use because of differences in exposure conditions. 1.3 This Standard Practice does not cover the following: 1.3.1 Special coatings agreed to by the purchaser and th

19、e manufacturer. 1.3.2 Coatings for special service conditions such as salt water, acid, high temperature, etc. 1.3.3 Internal areas of fire hydrants that are downstream of the main valve. 2. DEFINITIONS Under this Standard Practice, the following definitions shall apply: 2.1 Application The method b

20、y which the coating material is applied or deposited on the valve, hydrant, fitting, or component part thereof. Methods of application may include, but are not restricted to, the following: a) Powder coating material may be applied using a fluidized bed or an electrostatic spray system. The method u

21、sed requires a preheating or post-heating process. b) Liquid coating material may be applied by air, airless, or electrostatic spray, by brush, or other methods. 2.2 Coating A material applied on the interior surfaces of a valve, hydrant, fitting, or component part thereof, meeting the requirements

22、of this Standard Practice. 2.3 Coating Applicator The party, who may or may not be the manufacturer of the valves, valve components, hydrants, hydrant components, or fittings who applies a coating that meets the requirements of this Standard Practice. 2.4 Coating Manufacturer The producer or manufac

23、turer of the liquid or powdered coating material. 2.5 Coating System Those materials and procedures used to coat a valve, hydrant, fitting, or a component part thereof. 2.6 Disbondment A loss of adherence between a protective coating and the metal substrate. 2.7 Ferrous Surface The surface of a valv

24、e, valve component part, hydrant, hydrant component part, or fitting made from gray iron, ductile iron, or ferritic steel. 2.8 Holiday A void or discontinuity in the non-conductive coating which can be detected visually or electrically. 2.9 Holiday Test A non-destructive test to electrically determi

25、ne the presence, if any, of voids or holidays in a coating. 2.10 Inspector The representative of the purchaser authorized to inspect on behalf of the purchaser to determine whether the requirements of this Standard Practice are met. 2.11 Liquid Coating Material A single or multiple component, homoge

26、neously mixed material applied in liquid form that provides a heat-activated or chemically cured coating. 2.12 Manufacturer The party producing the valves, hydrants, fittings, or component parts thereof, which are coated in accordance with this Standard Practice. PROTECTIVE COATINGS FOR THE INTERIOR

27、 OF VALVES, HYDRANTS, AND FITTINGS MSS STANDARD PRACTICE SP-982 2.13 Powder Coating Material A material applied in powder form that provides a heat-activated or chemically cured coating. 2.14 Purchaser The party entering into a contract or agreement to purchase coated valves, hydrants, fittings, or

28、component parts thereof, according to this Standard Practice. 2.15 Reclaimed Water Wastewater that becomes suitable for beneficial use as a result of treatment. 2.16 Wastewater A combination of the liquid and water-carried waste from residences, commercial buildings, industrial plants and institutio

29、ns, together with any groundwater, surface water, and storm water that may be present. 3. AFFIDAVIT OF COMPLIANCE 3.1 The manufacturer, if required by the Purchase Order, shall furnish an affidavit of compliance stating that the coating of the valves, hydrants, or fittings conforms to the applicable

30、 requirements of this Standard Practice. 4. COATINGS FOR DRINKING WATER SERVICE 4.1 Coatings for drinking water service shall not contain coal tar and shall comply with one or more of the following requirements (as applicable): a) Formulated from materials deemed acceptable in the U.S. Food and Drug

31、 Administration (FDA) Chapter of Title 21 of the U.S. Code of Federal Regulations on Indirect Food Additives, Subsection 175.300, entitled “Resinous and Polymeric Coatings”. b) NSF 61, Drinking Water System Components Health Effects. c) The Safe Drinking Water Act; as Amended (40 C.F.R. 141; U.S. EP

32、A). 5. SURFACE PREPARATION 5.1 Visual Examination Prior to surface preparation, each valve, valve component, hydrant, hydrant component, or fitting to be coated shall be visually inspected for cleanliness and surface profile recommended for immersion service by the coating manufacturer. 5.2 Surface

33、Preparation Surface preparation shall provide the surface profile that is recommended by the coating manufacturer for immersion service. 6. COATING APPLICATION 6.1 Powder coating materials may be applied to preheated components using a fluidized bed, pneumatic spray system, or an electrostatic spray

34、 system. The method used may require a post-heating process. 6.2 Liquid coating materials may be applied by air, airless, electrostatic spray, brush, or by electrophoretic deposition. 6.3 The protective coating, whether a liquid or powder material, shall be applied to interior ferrous surfaces in co

35、nstant contact with water, drinking water, or reclaimed and wastewater. Unless otherwise required by the Purchase Order, the protective coating may be applied to any exterior ferrous surfaces of valves, hydrants, and fittings at the manufacturers option. 6.4 Certain surfaces may be left uncoated pro

36、vided that the anticipated corrosion of these areas will not interfere with the effective performance of the valve, hydrant, or fitting. These surfaces include, but are not limited to, interior machined surfaces, bearing surfaces, mating surfaces of gaskets or other elastomeric stem seals; interior

37、dry-barrel hydrant surfaces above the shoe; interior wet-barrel hydrant surfaces below the upper barrel; corrosion-resistant surfaces such as stainless steel and copper alloys; and other surfaces that, if coated, would impair the effective performance and operation of the valve, hydrant, or fitting.

38、 MSS STANDARD PRACTICE SP-983 6.5 Special consideration may be necessary on the protective coating thickness for machined surfaces, bearing surfaces, mating surfaces and joint dimensions of valve, hydrant, and fitting end connections to maintain a functional product. 7. COATING SYSTEM QUALIFICATION

39、7.1 The coating materials and procedures that the manufacturer uses for coating valves, hydrants, fittings, and or component parts thereof, shall be qualified in accordance with this Standard Practice. 7.1.1 If coating material composition or application procedure parameters are modified to be outsi

40、de the tolerance range of the original composition or parameters, the modified coating materials and or procedures shall be qualified in accordance with this Standard Practice. 7.2 The manufacturer shall maintain certificates of compliance from the coating manufacturer that the coating materials mee

41、t the requirements of Section 4.1 of this Standard Practice. 8. QUALIFICATION TESTING 8.1 Test Coupons The coating material shall be applied to the test coupons approximately 4 in. (100 mm) square. For each subsequent test (i.e., Section 8.1.1 to 8.1.5), a separate coated coupon shall be used. The t

42、est coupons shall be made of the same material, shall be the same thickness, and the surface roughness shall be similar to the product that is to be coated. The test coupons shall be coated on all surfaces with the same thickness of protective coating material that is to be applied to the valve and

43、hydrant components, or fittings, and it shall have the same surface preparation and application procedure that is to be used to coat the valve, hydrant, or the fitting. The coating shall be fully cured before testing. 8.1.1 Distilled Water Immersion Test A coated test coupon shall be scribed with a

44、sharp instrument through the coating material, down to the metal surface of the coupon for the maximum length possible. The minimum scribed mark shall be an “X” that is 3 in. (75mm) wide by 3 in. (75 mm) tall. The coated and “scribed” test coupon shall be immersed in distilled water at a temperature

45、 of 150 F (65.6 C) for 90 days. Following exposure, the test coupon is to be visually examined. There shall be no evidence of disbondment, undercutting, or blistering of the coating. 8.1.2 Sodium Chloride Immersion Test A coated test coupon is immersed in a sodium chloride solution (2% by weight) at

46、 a temperature of 158 F 2 F (70 C 1 C) for 90 days. Following exposure, the test coupon is to be visually examined. There shall be no evidence of disbondment, undercutting, or blistering of the coating. 8.1.3 Potassium Biphthalate Immersion Test A coated test coupon is immersed in a potassium biphth

47、alate solution (pH 4) at a temperature of 158 F 2 F (70 C 1 C) for 90 days. Following exposure, the test coupon is to be visually examined. There shall be no evidence of disbondment, undercutting, or blistering of the coating. 8.1.4 Sodium Carbonate Immersion Test A coated test coupon is immersed in

48、 a sodium carbonate solution (pH 10) at a temperature of 158 F 2 F (70 C 1 C) for 90 days. Following exposure, the test coupon is to be visually examined. There shall be no evidence of disbondment, undercutting, or blistering of the coating. 8.1.5 Direct Impact Test No cracking of the coating materi

49、al under the indentor of the impact apparatus described in ASTM D2794 shall be visible without magnification, after a direct impact of 20 inch-lbf (2.26 J) is applied near the center of the surface of the test coupon. Only that section of ASTM D2794 describing the impact apparatus shall be applicable to this Standard Practice. MSS STANDARD PRACTICE SP-984 9. PRODUCTION TESTING 9.1 All coated surfaces shall be examined before assembly and where practical, after assembly. 9.2 Tests described in Sections 9.2.1 and 9.2.2 shall be performed on an ongoing basis, a