D4020 is just the material spec for extrusion materials, not for pipe. It does not provide physical properties information requirements such as hydrostatic design base (HDB), tensile strength, etc. to determine the wall thickness required for pressure containment. Is there such a standard...
The simplest solution is to select a valve that is NSF 61 certified.
Check the following NSF website for the product.
http://info.nsf.org/Certified/PwsComponents/index.asp?standard=061
B31.3 para 345.2.3 (b) stated:
"Flanged joints used to connect piping components and subassemblies that have previously been tested, and flanged joints at which a blank or blind is used to isolate equipment or other piping during a test, need not be leak tested in accordance with para. 345.1"...
It depends on what code you are building to.
donf gave you the B31.3 requirement.
AWWA C207 required that "minimum bolt length shall be the sum of the mating flange maximum thicknesses, the gasket, and the depth of the nut plus 1/2" before torquing."
B31.1 does not allow miter in steam pipe.
Para 104.3.3 (A.3)stated that miters may be used only if "The contained fluid is nonflammable, nontoxic, and incompressible, except for gaseous vents to atmosphere"
Since steam is a ompressible fluid, if follows that miter is NOT permitted.
The standard of the pipe you are specifying (e.g. ASTM A53, A106, etc) has paragraphs about pipe lengths.
For example, section 17 of ASTM A106 stated:
17.1.1 The lengths required shall be specified in the order,
and
17.1.2 No jointers are permitted unless otherwise specified.
17.1.3 If definite...
First, you cannot use A240 for pipe. Para 123.1.1 (B) of B31.1 stated:
"A material conforming to a specification for which
allowable stresses are not listed in Appendix A is acceptable provided its use is not specifically prohibited by this Code Section and it satisfies one of the following...
Use a HDPE flange adaptor(http://www.kwhpipe.ca/pdfs/IPS_Flange_Adapters.pdf)
and a metal backing flange
(http://www.kwhpipe.ca/pdfs/IPS_Ductile_Iron_Flange.pdf)
All these metal backing flanges have bolt pattern that match ANSI flanges.
The piping code is the document you need. Each piping code has different methods of calculating pressure limitations. Since your pipeline is built to B31.8, that is the document you should use. Specifically, Section 841 of B31.8.
In addition, you need to know more about the pipe than just...
