ASME PCC-1-2010 pdf download

ASME PCC-1-2010 pdf download.Guidelines for Pressure Boundary Bolted Flange Joint Assembly.
(a) Verify that the gasket complies with the dimen- sional (O.D., I.D., thickness) and material specifications. (b) Position the gasket to be concentric with the flange I.D., taking suitable measures to ensure that it is ade- quately supported during the positioning process. No portion of the gasket should project into the flow path. (c) Ensure that the gasket will remain in place during the joint assembly process; a very light dusting of spray adhesive on the gasket (not the flange) may be used. Particular care should be taken to avoid adhesive chem- istry that is incompatible with the process fluid or could result in stress corrosion cracking or pitting ofthe flange surfaces. Do not use tape strips radially across the gasket to hold it in position. Do not use grease. 7 LUBRICATION OF “WORKING” SURFACES 5 Lubrication reduces the coefficient of friction and results in less required torque to achieve a given tension, improves the consistency of achieved load from bolt to bolt within the joint, and aids in the subsequent disas- sembly of the fasteners. The reference torque values for new, coated bolts/ nuts shown in Table 1M/Table 1 do not consider lubrica- tion other than that provided by the bolt/nut coating [see Note (2) of Table 1M/Table 1]. When reusing coated bolts or if lubricant is applied to new or reused coated bolts,the NutFactorwill change andtherefore thetorque values should be adjusted accordingly (refer to Appendix K). Do not apply either approved lubricant or unapproved compounds to the gasket or gasket-contact surfaces; protect against inadvertent application to these surfaces. (a) Ensure that the lubricant is chemically compatible with the bolt/nut/washer materials and the process fluid. Particular care should be taken to avoid lubricant chemistry thatcould contribute to stress corrosion crack- ing, galvanic corrosion, oxygen auto-ignition, etc. (e) For new coated bolts and nuts (see Notes to Table 1M/Table 1), free running nut checks as described in (c) are required; however, lubricant application as described in (d) should be limited to the second and subsequent tightening operations since the coating pro- vides sufficient lubrication for the first tightening. (1) The reference torque values for new, coated bolts/nuts shown in Table 1M/Table 1 do not consider lubrication other than that provided by the bolt/nut coating[see Note (2) ofTable 1M/Table 1]. Whenreusing coated bolts or if lubricant is applied to new or reused coated bolts, the Nut Factor will change and therefore the torque values should be adjusted accordingly (refer to Appendix K). (f) While it is recognized that the inherent lubricity of new coated bolts results in less torque being required during the first tightening operation to achieve a given level of tension in the bolt (see Table 1M/Table 1), the major long-term value of coated bolts is to protect against corrosion of the exposed threads and to mini- mize break-out and nut-removal torque, thereby pro- moting ease of joint disassembly [see section 15, and Note (3) of Table 1M/Table 1]. (g) Do not apply either approved lubricant or unap- proved compounds to the gasket or gasket-contact sur- faces; protect against inadvertent application to these surfaces. 8 INSTALLATION OF BOLTS Install bolts and nuts so they are hand-tight with the marked ends of the bolts and nuts located on the same side of the joint and facing outward to facilitate inspec- tion; thensnug up to 15 N·m (10 ft-lb) to 30 N·m (20 ft-lb), but not to exceed 20% of the Target Torque (see section 12). If nuts do not hand tighten, check for cause and make necessary corrections. 8.1 Bolt/Nut Specifications Verify compliance with bolt and nut specifications [materials, diameter, length of bolts, thread pitch, and nut thickness equal to the nominal bolt diameter (heavy hex series nuts)].