7.10　Blow-off valve，Equalizer valve on top

General Items

7.10.1　The joint face between valve seat and valve petal shall be checked with a feeler gauge before installation of blow-off valve，equalizing valve on top，the sealing conditions shall meet the requirements in the design documents.And it shall meet the requirements in Appendix F when not specified.

Check quantity:full check.

Check method:check the installation quality records，check with a feeler gauge.

7.10.2　The packing（backing）seal on flange face between valve and pipe shall meet the requirement in the design documents.They shall be closely contacted.The flange and connecting bolt shall be installed according to current national standard GB 50235 Code for Construction and Acceptance of Industrial Metallic Piping.

Check quantity:random check for 2 sets.

Check method:observe and check with a feeler gauge or steel rule.

7.10.3　The allowable installation deviation of blow-off valve，equalizing valve shall meet the requirements in Table 7.10.3.

Check quantity:full check.

Check method:see Table 7.10.3.

Table 7.10.3　Allowable installation deviation of blow-off valve，equalizing valve on top（mm）