ASME PCC-1:2000 pdf download CUIDELINES FOR PRESSURE BOUNDARY BOLTED FLANGE JOINT ASSEMBLY
1 SCOPE
The bolted flange joint assembly (BFJA) guidelines described in this document apply to pressure-bound- ary flanged joints with ring-type gaskets that are entirely within the circle enclosed by the bolt holes and with no contact outside this circle.’ By selection of those features suitable to the specific service or need, these guidelines may be used to develop effective joint assembly procedures for the broad range of sizes and service conditions normally en- countered in the process industries.
2 INTRODUCTION A BFJA is a complex mechanical device; therefore, BFJAs that provide leak-free service are the result of many selectiondactivities having been rnade/per- formed within a relatively narrow band of acceptable limits. One of the activities essential to leak-free performance is the joint assembly process.
The guide- lines outlined in this document cover the assembly elements essential for consistent leak-tight perform- ance of otherwise properly designedkonstructed BFJAs. It is recommended that written procedures, incorporating the features of these guidelines that are deemed suitable to the specific application under consideration, be developed for use by the joint assemblers.
3 QUALIFICATION The user or his designated agent should provide, or arrange to have provided, as appropriate, essential training and qualification testing of the joint assem- blers who will be expected to follow procedures developed from this Guideline.
Qualification of the selected joint assembly procedure may be appropriate for critical applications.
Appendix A provides some notes on qualifying flanged joint assemblers.
Appendix B provides a recommended flanged joint assembly procedure qualification test.
4 EXAMINATION OF “WORKING” SURFACES Clean and examine all “working” surfaces before assembly is started.
(a) Examine the gasket contact surfaces of both joint flanges for appropriate surface finish (see Ap- pendix C) and for damage to surface finish such as scratches, nicks, gouges, and burrs. Indications running radially across the facing are of particular concern. Report any questionable imperfections for appropriate disposition.
(b) Check gasket contact surfaces of both joint flanges for flatness, both radially and circumferen- tially. Report any questionable results. Appendix D provides a recommendation for flatness tolerance.
c) Examine bolt’ and nu threads and washer faces of nuts for damage such as rust, corrosion, and burrs; replace questionable parts. If separate washers’ are scored or cupped from previous use, replace with new through-hardened washers (sur- face-hardened washers are not suitable). Previously used bolts should be thoroughly cleaned (such as wire brushing) before being reused.