PFI ES-39-2008 FABRICATING TOLERANCES FOR GROOVED PIPING SYSTEMS《沟槽管道系统预制公差》.pdf

1、PFI Standard ES-39 (Reaffirmed - September 2010) FABRICATING TOLERANCES FOR GROOVED PIPING SYSTEMS Prepared by Pipe Fabrication Institute Engineering Committee All PFI Standards are advisory only. There is no agreement to adhere to any PFI Standard and their use by anyone is entirely voluntary. Copy

2、right by PIPE FABRICATION INSTITUTE Dedicated to Technical Advancements and Standardization in the Pipe Fabrication Industry Since 1913 USA 511 Avenue of Americas, # 601 New York, NY 10011 CANADA 655, 32ndAvenue, # 201 Lachine, QC H8T 3G6 WEB SITE www.pfi-institute.orgPFI Standard ES-39 (Reaffirmed

3、- September 2010) ES-39 FABRICATING TOLERANCES FOR GROOVED PIPING SYSTEMS PFI does not endorse, approve, or recommend any specific product by issuance of this standard. METRIC CONVERSIONS The conversion of quantities between systems of units involves a determination of the number of significant digi

4、ts to be retained. All conversions depend upon the intended precision of the original quantity and are rounded to the appropriate accuracy. Pipe sizes together with applicable wall thicknesses are not shown with metric equivalents. The SI (metric) values where included with the customary US values i

5、n this Standard are the rounded equivalents of the US values and are for reference only. Metric units were derived utilizing the following conversion factor: Conversion Factor inches to 25.4 millimeter 1. Scope 1.1 This standard covers general pipe shop fabricating tolerances for prefabricated groov

6、ed piping assemblies. 2. Linear Tolerances 2.1 The tolerances on linear dimensions (intermediate or overall) apply to the face to face, face to end, and end to end measurements of fabricated straight pipe and headers; center to end or center to face of nozzles or other attachments; or center to face

7、 of bends; as illustrated on Fig. 1. These tolerances are not accumulative. 2.2 Linear tolerances on “A” are 1/8“ (3.0mm) for sizes 10“ and under, 3/16“ (5.0mm) for sizes 12“ through 24“ and 1/4“ (6.0mm) for sizes over 24“ through 36“. 2.3 Linear tolerances on “A” for sizes over 36“ are subject to t

8、olerances of 1/4“ (6.0mm), increasing by plus or minus 1/16“ (2.0mm) for each 12“ in diameter over 36“. 2.4 Due to the cumulative effects of tolerances on fittings or flanges, when joined without intervening pipe segments, deviations in excess of those specified in paragraph 2.2 and 2.3 may occur. 3

9、. Groove Dimensions and Tolerances 3.1 Grooves used to join piping assemblies with mechanical pipe joint couplings may be rolled or cut, as specified by the purchasers engineer, and in accordance with the coupling manufacturers recommendations. Grooves for ductile iron pipe and other metallic pipe m

10、eeting iron pipe size (IPS) dimensions shall comply with ANSI/AWWA C606-04, AWWA “Standard for Grooved and Shouldered Joints”. 3.2 Manufacturers of mechanical pipe joint couplings offer proprietary grooved systems for Carbon Steel, Stainless Steel, Copper, Aluminum and PVC pipe. The groove dimension

11、s required for these proprietary systems may vary from the ANSI/AWWA C606-04 dimensional standard. Consult the coupling manufacturer for proper equipment and dimensional requirements. 3.3 The outside diameter pipe shall be within the coupling manufacturers recommended tolerances. 3.4 Maximum pipe ov

12、ality should not vary by more than 1% for standard weight pipe or thinner. PFI Standard ES-39 (Reaffirmed - September 2010) 3.5 The pipe outside diameter, groove diameter and pipe end flare shall be verified to assure proper fit of the pipe joint coupling. A calibrated vernier periphery measuring ta

13、pe is the recommended method for checking these dimensions. Measuring instruments shall be calibrated to a recognized standard. 3.6 The selection of the proper roll grooving machine, groove rolls or cutting knives, and pipe stops shall be compatible with the pipe size and type of material being groo

14、ved and in accordance with the manufacturers recommendations. When other equipment is used, it will be the fabricators responsibility to ensure that all dimensions and recommendations mentioned in this standard are met to insure proper installation. 3.7 Groove tolerances that vary from referenced ab

15、ove, those given above, shall be subject to agreement between the Purchaser and the Fabricator. PFI Standard ES-39 (Reaffirmed - September 2010) END PREPARATION FORGROOVE SHALL NOTDEVIATE FOR INDICATEDPOSITION BY MORE THAN1/32“ (1.0mm) ACROSSTHE PIPE END.FOR BENDING TOLERANCE, MINIMUMRADIUS AND MINIMUM TANGENT SEE PFI STANDARD ES-24TOLERANCES ON DIMENSIONS WHICH DONOT INCLUDE PIPE SEGMENTS ARE TO BEBASED ON MANUFACTURES SPECIFICATIONSFOR FITTINGS OR FLANGES INVOLVED.(SEE PARAGRAPH 2.4)“A“A“A“A“A“A“FIGURE 1APPLICATION OF PIPE FABRICATION TOLERANCES