6.4　Bedding Trough，Mixed Trough

Ⅰ　Dominant Item

6.4.1　Welding quality shall meet requirements of design technical document；if not required in design technical document，it must meet requirements of IV class weld seam quality in current national standard GB 50236 Code for Construction and Acceptance of Field Equipment and Industrial Pipe Welding Engineering.

Check quantity:spot check 20% of weld seam length.

Inspection method:to inspect，to check weld seam with gauge.

6.4.2　For trough with sensors，trough must not directly be installed on sensors.

Check quantity:to check all.

Inspection method:observation.

Ⅱ　General Item

6.4.3　Tolerance for installation of bedding trough and mixed trough shall meet requirements in Table 6.4.3.

Check quantity:to check all.

Inspection method:see Table 6.4.3.

Table 6.4.3　Tolerance for installation of bedding trough and mixed trough