1、 MSS SP-112-2010 Quality Standard for Evaluation of Cast Surface Finishes Visual and Tactile Method Standard Practice Developed and Approved by the Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. 127 Park Street, NE Vienna, Virginia 22180 Phone: (703) 281-6613 Fax: (70
2、3) 281-6671 e-mail: infomss-hq.org www.mss-hq.org MSS STANDARD PRACTICE SP-112i This MSS Standard Practice was developed under the consensus of the MSS Technical Committee 304 and the MSS Coordinating Committee. The content of this Standard Practice is the result of the efforts of competent and conc
3、erned volunteers to provide an effective, clear, and non-exclusive specification that will benefit the industry as a whole. This MSS Standard Practice is intended as a basis for common practice by the manufacturer, the user, and the general public. The existence of an MSS Standard Practice does not
4、in itself preclude the manufacture, sale, or use of products not conforming to the Standard Practice. Mandatory conformance is established only by reference in a code, specification, sales contract, or public law, as applicable. “Unless otherwise specifically noted in this MSS Standard Practice, oth
5、er standards documents referred to herein are identified by the date of issue that was applicable to this Standard Practice at the date of issue of this Standard Practice. See Annex A. This Standard Practice shall remain silent on the applicability of those other standards of prior or subsequent dat
6、es of issue even though applicable provisions may not have changed. References contained herein which are bibliographic in nature are noted as supplemental in the text.” By publication of this Standard Practice, no position is taken with respect to the validity of any potential claim(s) or of any pa
7、tent rights in connection 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 notes, annexes, table
8、s, and figures are construed to be essential to the understanding of the message of the standard, and are considered part of the text unless noted as “supplemental“. All appendices, if included, that appear in this document are construed as “supplemental“. Supplemental information does not include m
9、andatory requirements for this Standard Practice. Substantive changes in this 2010 edition are “flagged” by parallel bars as shown on the margins of this paragraph. The specific detail of the change may be determined by comparing the material flagged with that in the previous edition. U.S. customary
10、 units in this Standard Practice are the standard; (SI) metric units are for reference only. Non-toleranced dimensions in this Standard Practice are nominal, and, unless otherwise specified, shall be considered “for reference only”. Any part of this Standard Practice may be quoted. Credit lines shou
11、ld read Extracted from MSS SP-112-2010 with permission of the publisher, Manufacturers Standardization Society of the Valves and Fittings Industry, Inc. Reproduction is prohibited under copyright convention unless written permission is granted by Manufacturers Standardization Society of the Valve an
12、d Fittings Industry Inc. Originally Approved: January 1993 Originally Published: March 1993 Current Edition Approved: September 2010 Current Edition Published: December 2010 Copyright , 1993, 1999, 2010 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.
13、A. MSS STANDARD PRACTICE SP-112ii FOREWORD One of the MSS Cast Surface Comparators, as described in Section 4 and Figure 1, is included with the purchase of the printed version of this Standard Practice because it is a necessary and normative part of the Standard Practice. However, the Comparator is
14、 a “necessary and normative” part of the Standard Practice whether purchased in printed form or electronically. Those purchasing this Standard Practice electronically may submit a receipt to MSS within 30 days of payment and receive a Comparator at no charge. Additional MSS Cast Surface Comparators
15、may also be purchased via our web site or home office. MSS STANDARD PRACTICE SP-112iii TABLE OF CONTENTS SECTION PAGE PURPOSE . 1 1 SCOPE 1 2 DEFINITIONS . 1 3 CAST SURFACE FINISH . 1 4 MSS CAST SURFACE COMPARATOR . 1 5 PROCEDURE 2 6 ACCEPTANCE OR REJECTION . 2 FIGURE 1 MSS CAST SURFACE COMPARATOR .
16、 3 ANNEX A Referenced Standards and Applicable Dates . 4 1 PURPOSE a) To establish an easy “sight and feel“ method for the quality evaluation of cast surface finishes. b) To make available a Cast Surface Comparator with MSS surface rating numbers 1 through 10, to be used to monitor surface finish by
17、 a visual and tactile method. c) To provide guidance on surface finish by “sight and feel“ to minimize misunderstanding which may occur between purchaser and manufacturer. 1. SCOPE 1.1 This surface quality Standard Practice provides criteria for the visual and tactile evaluation of cleaned AS-CAST s
18、urface finishes of components manufactured from castings. 1.2 This Standard Practice and its supporting MSS Cast Surface Comparator may be applied to surfaces formed by any casting method. 1.3 This Standard Practice provides visual and tactile criteria for evaluating casting surface finish and textu
19、re, which can be used to develop an acceptable quality level. 1.4 Cast surfaces on materials such as gray iron, ductile iron, bronze, and malleable iron may be compared with the use of this Standard Practice; however, it is not the intention of this Standard Practice to limit comparisons to only the
20、se types of materials. 1.5 This Standard Practice does not apply to machined surfaces or those surfaces that are intended to be machined. 1.6 This Standard Practice is limited to “sight and feel“ by comparison without measurement. Luster and color are not part of this Standard Practice. 1.7 This Sta
21、ndard Practice is not intended for use on those castings where burn-in, slag, scabs, etc. so distort the surface that the comparator cannot be used and the casting may be rejected for other causes. 2. DEFINITIONS Refer to ASME B46.1, “Surface Texture (Surface Roughness, Waviness, and Lay)”. 3. CAST
22、SURFACE FINISH 3.1 General There are many methods of measuring cast surface finishes to establish a criteria for quality acceptance limits. These are primarily by measurement or pictures. See the references listed in Annex A of this Standard Practice for other inspection methods; including ASTM A802
23、, MSS SP-53, MSS SP-55, and MSS SP-93. 3.2 Cast Surface finishes involve texture, roughness, waviness, lay and flaws. For definitions and other actual measurement methods for various surface irregularities refer to ASME B46.1 or any of the other referenced standards. 3.3 The casting method and mater
24、ial used will influence the surface roughness. Consideration must be given to the actual acceptable surface finish and its final function. A mutual agreement should be made between purchaser and manufacturer. 3.4 The degree of roughness forms the criteria of this Standard Practice. Through the use o
25、f the MSS Cast Surface Comparator and its 10 three-dimensional surfaces, an acceptable cast surface finish can be agreed upon. 4. MSS CAST SURFACE COMPARATOR 4.1 The MSS Cast Surface Comparator is an economical, convenient “pocket size“ QUALITY STANDARD FOR EVALUATION OF CAST SURFACE FINISHES VISUAL
26、 AND TACTILE METHOD 2 Comparator for inspection and quality acceptance of cast surface finishes. 4.2 The MSS Cast Surface Comparator was designed and manufactured using actual representative samples of cast surfaces. Numbers were then assigned to establish the degree of roughness. 4.3 Neither optica
27、l magnifiers nor measuring instruments are required to perform the surface inspection. It is a visual and tactile method. 4.4 The MSS Cast Surface Comparator is a three dimensional representation of AS-CAST surface finishes with numbers ranging from 1 through 10. The surface texture roughness of a s
28、urface which needs to be qualified is rated by means of comparison to the MSS Cast Surface Comparator. Visual and tactile comparisons can be made by using this Surface Comparator. See Figure 1 for an illustration of the MSS Cast Surface Comparator. 4.5 Casting surface roughness acceptance levels can
29、 be established through the use of the MSS rating numbers 1 through 10, regardless of casting method and/or material. A comparison can be designated by an acceptable MSS number and/or range between numbers. The lower the MSS number, the smoother is the surface finish. 5. PROCEDURE 5.1 General The qu
30、ality acceptance level should be established by prior agreement of the customer and manufacturer and be based on the intended use and function of the casting. Requirements for some areas of the castings may be for cosmetic appearance, rather than function. The MSS number selected can either be a max
31、imum or a minimum. The cast surface finish required can also be designated as between two MSS numbers. It may be desirable to establish different MSS numbers for different areas of a casting. This is based on whether the entire casting should have the same general surface smoothness requirement or i
32、f certain areas are more or less critical than others. 5.2 Cleanliness The cast surface to be inspected should be clean and free of dirt, oil, loose sand, or other foreign material that would impair an accurate determination of the surface finish. 5.3 Surface Evaluation Place the MSS Cast Surface Co
33、mparator near the surface to be inspected. By “sight and feel”, compare the casting surface to the comparator surface, utilizing the quality acceptance level established in Section 5.1. Luster and color should not be a consideration; only roughness. 6. ACCEPTANCE OR REJECTION Based on the surface ev
34、aluation in Section 5 and an agreed upon surface roughness level, the cast part shall be accepted or rejected. 3 SMOOTH ROUGH DEGREE OF SURFACE FINISH MATERIAL: Molded Durable Plastic - 1/8“ Thick Color: Gray FIGURE 1 MSS CAST SURFACE COMPARATOR (FOR VISUAL AND TACTILE INSPECTION) 4 ANNEX A Referenc
35、e Standards and Applicable Dates This Annex is an integral part of this Standard Practice and is placed after the main text for convenience. Standard Name Description ASME; ANSI/ASME B46.1-2009 Surface Texture (Surface Roughness, Waviness, and Lay) ASTM A802/A802M-95(2006) Standard Practice for Stee
36、l Castings, Surface Acceptance Standards, Visual Examination MSS SP-53-1999 (R 2007) Quality Standard for Steel Castings and Forgings for Valves, Flanges, and Fittings and Other Piping Components Magnetic Particle Examination Method SP-55-2006 Quality Standard for Steel Castings for Valves, Flanges,
37、 Fittings, and Other Piping Components Visual Method for Evaluation of Surface Irregularities Note: The updated edition of SP-55 (to be published in 2011) was also reviewed during the revision of this SP-112-2010 and accepted as being compatible with this Standard Practice. The usage of the revised
38、SP-55-2011 is preferred. SP-93-2008 Quality Standard for Steel Castings and Forgings for Valves, Flanges, Fittings, and Other Piping Components Liquid Penetrant Examination Method Publications of the following organizations appear in the above list: ASME American Society of Mechanical Engineers Thre
39、e Park Avenue New York, NY 10016-5990 ASTM ASTM International 100 Bar Harbor Drive, P.O. Box C700 West Conshohoken, PA 19428-2959 MSS Manufacturers Society of the Valve and Fittings Industry, Inc. 127 Park Street, N.E. Vienna, VA 22180-4602 Listing of MSS Standard Practices TITLE SP-6-2007 Standard
40、Finishes for Contact Faces of Pipe Flanges and Connecting-End Flanges of Valves and Fittings SP-9-2008 Spot Facing for Bronze, Iron and Steel Flanges SP-25-2008 Standard Marking System for Valves, Fittings, Flanges, and Unions SP-42-2009 Corrosion Resistant Gate, Globe, Angle and Check Valves with F
41、langed and Butt Weld Ends (Classes 150, 300 however, the contents of these SPs are now part of newly revised SP-58-2009. MSS is an ANSI-accredited American National Standards developer. A number of former MSS Standard Practices have been adopted and published by other developers as American National
42、 Standards. In order to maintain a single source of authoritative information, MSS has withdrawn its Standard Practices in such cases. Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. 127 Park Street, N.E., Vienna, VA 22180-4620 (703) 281-6613 Fax # (703) 281-6671 MSS-IHS SP-112-2010
