Since the primary version of the AWWA Standard C207 was printed in 1952, AWWA flanges have commonly been utilized in waterworks, wastewater, slurry, plant piping, and other gentle responsibility purposes. Pressure ratings for AWWA flanges vary from the class B flange rated at 86 psi to the category F flange rated at 300 psi. The AWWA C207-01 commonplace describes two varieties of slip-on flanges, ring sort and hub sort that may be used interchangeably if the dimensions given in the standard are used. The standard additionally describes blind flanges. Flanges described within the AWWA C207-01 tables are intended to be used with steel pipe, fittings or appurtenances meeting the necessities of ANSI/AWWA C200, ANSI/AWWA C208, ASTM A134, ASTM 139, or other equivalent requirements. It’s further supposed that these flanges be connected by welding in accordance with AWWA C207-01 Sec.4.3.Pressure Ratings
As per AWWA C207-01 Sec. 1.3, the stress rankings listed for AWWA Class B, D, E and F flanges are for circumstances and temperatures customary in water utility companies. If you beloved this article and you simply would like to be given more info with regards to mechanical steel (https://rspcb.safety.fhwa.dot.gov/) nicely visit our web page. The strain scores for the flange needs to be based on the design of the maximum operating strain plus the anticipated certain pressure. Test pressures shouldn’t exceed 125 % of the rankings. Flange design is predicated on pressure concerns, not for stresses induced by exterior moments when pipe acts as a beam. The tables of the AWWA C207-01 standard have been developed using a design stress of 16,000 psi for the working strain design.Flange Material
As per AWWA C207-01, Sec 4.1, flanges shall be made from seamless forgings, cut from plate as a single piece, welded bar rings or segmented and welded plates as per C207-01 Sec 4.2.4.
Forgings shall meet the minimum necessities or ASTM A105 or A181.
Steel plate or bar used within the manufacture of flanges shall meet the next requirements:
1. Tensile power = 50,000 psi (345 mpa) (min.)
2. Yield strength = 32,000 psi (221 mpa) (min.)
3. Carbon = 0.29 % (max.)
4. Phosphorous = 0.04 percent (max.)
5. Sulfur = 0.05 p.c (max.)
Plate steel designations that may meet the beforehand listed necessities embody but will not be restricted to the following designation: 1. A362. A516, grade 60, 65, and 70
Pacific Coast Flange Inc will provide mill test reports exhibiting conformance to the physical and chemical necessities for mechanical steel all flanges ordered.Flange Facing
As per AWWA C207-01 Sec 4.2.2, all AWWA flanges shall be flat-faced with out projection or raised area of face. Either a serrated concentric or serrated spiral finish having from 24 grooves per inch to 470 grooves per inch shall be used. The slicing device employed shall have an approximate 0.06 inch or bigger radius. The resultant floor finish shall have a 250 to 500-uin. roughness.Drilling Templates
As per AWWA C207-01 Sec. 4.2.3 drilling templates are in multiples of 4 so that fittings may be make to face any quarter. Bolt holes shall straddle the center line, besides the place special mating situations exist and shall be drilled 1/8 in. (3.2mm) larger in diameter than the nominal diameter of the bolt, except on flanges larger that eighty four inches (2,100mm) diameter, bolt holes shall be drilled 3/16 inches (4.8mm) bigger than the nominal bolt diameter. Bolt holes could also be over drilled by a further 1/8 in (3.2mm) to accommodate insulators or to facilitate alignment with the mating flange.