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Product Material Standard
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Product Material Standard

The unique,C-shape,pressure responsive gaskets design has been the heart of the grooved systems since its inception,Relying on compound compression set and the initially flared design,the gasket seals on the dimension of the pipe movement noted,while sealing under both pressure and vacuum,The manufacture and test is to ASTM D2000 and UL 157 quality controlled with test of hardness strength,strength at break,elongation at break
change in hardness,change in strength at break,change in elongation at break,and low temperaure compression set available rubber compounds now include the standard gasket EPDM for water (2300F/+1100C)and nitrile compound gasket for oil services (to+1800F/+820C). Specila gasket include fluoroelastomer,neoprene,silicone ,white nitrile and epichlorohydrin Each gasket is traceable by being marked with manufacturing date,fomula code and operator's code,During assembly,the gasket is slightly stretched over the pipe ends,applying the natural compression of the angles lips as well as the resiliency of the entire gasket body It is important to note that grooved coupling gaskets always should be lubricated on the lips and the outside back before assembly,Assembly of the coupling housing over the gasket mates it closely to the gasker back,fully encasing the gasket with backbone of ductile iron,With the bolt pads fully tightened this adds additional compressive force without full compression leaving the natural resiliency as an active acaling force within the jount,The full compression leaving the natural resiliency as an active sealing force within the joint The full encasement of the gasket prevents any extursion of the rubber under high pressure.

  ANSI/NSF Standard 61 is a National Standard that was developed to establish minimum requirements for the control of potential adverse human health effect form products which contact drinking water.Its primary focus is on contaminants or impurities which may be imparted indirectly to potable water.Please note that material that do not come inderect contact with potable water do not require evaluation.The sealing material as established by ANSI/NSF 61 are "Cold"which is limited to -29.2ºF(-340C) Maximum and "Hot" which is limited to +230ºF(1200C) Maxinum.
 Coupling Housings
Stainless Steel:It is made of stainless steel with good mechanical properties(such as high strength,toughness and ductility)and the material has tensile strength not below 600Mpa(N/mm2)and elongation not below 15%,withstands high-pressure and high-impact of pipeline generated by several disadvantageous factors highly resists and absorbs vibration It is able to normally run under conditions requiring good mechanical properties The housing's material standard is according to Materials Engineering Association Of the United States Standard ASTM A351.
 Bolts and Nuts
The bots and nuts secure the entire joint together, The bolts are not taking the primary load, nor are they functional in the sealing process, The bolts hold the coupling housings into the grooves and contain the gasket, Once tightened, the bolts require no further tightening, There are no torque specifications for most grooved coupling as with flange bolts. The plated bolt head is an oval neck track bolt configuration conforming to openings in the housing bolt pads, This permits tightening the nuts from one side without a backup wrench. The standard stainless steel bolts are Type 316 Grade B8M Class 2 stainless steel to ASTM A-193, Stainless steels are susceptible to galling, which occurs when two of the same metals are rubbed together under a load, such as in the area of the thread contact between the bolt and nut at high torque,It iS common practice that when using stainless steel hardware to apply and anti—seize lubricant to the bolt to prevent galling, The carbon steel bolts conform to ASTM A-183 minimum tensile 110, 000 PSI providing identifiablestrength.

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