4.4　Auxiliary Pipeline and Equipment

4.4.1　Before the alloy steel pipelines and pipe fittings in boiler proper scope are in service，carry out spectrum reviewing one by one，and material marks shall be carried out.

4.4.2　The installation of pipelines and auxiliaries in boiler proper scope shall be in accordance with the following requirements:

1　The machining and installation of all kinds of pipes，supports，and hangers set up in site shall be in accordance with the following requirements:

1）The pipelines shall be overally planned with reasonable and simple layout，drain gradient and of artistic process.The pipe expansion arrangement shall meet the requirement of expansion direction and capacity；

2）The supports and hangers shall be reasonably arranged and fixed installed，the heat expansion of the pipe shall not be affected.

2　The installation of boiler blowdown and drainage water pipelines shall be in accordance with the following requirements:

1）Drain gradient of at least 0.2% shall be set up for pipe installation，and the free heat compensation shall be realized，and the heat expansion of drum，headers，and pipes shall not be affected；

2）The blowdown and drainage water pipes of difference pressure grades shall not be connected to the same header；

3）The connecting of blowdown pipe and header shall be carried out after the internal header is cleaned；

4）The blowdown and drainage pipes shall be unblocked.

3　The installation of sampling system shall be in accordance with the following requirements:

1）The installation direction of the samplers shall be correct；

2）The sampling cooler shall be installed as per design documentation，and carry out checking to the tightness of heat exchanging pipes before installation is carried out.

4　When installing steam exhaust pipes，the heat expansion clearance shall be available for free expansion of drum，header，and pipe；the supports and hangers of steam exhaust pipes shall be fixed.Weight of the steam exhaust pipe of safety valve shall not be imposed on the safety valve；

5　The inspection and preparation of pipes and auxiliaries in boiler proper scope shall comply with the related regulations of Chapter 7 of this code；

6　The throttling equipment shall be installed after the pipe chemical cleaning，flushing，and purging are completed.

4.4.3　The installation，commissioning and acceptance of the source component and gauges shall comply with the related regulations of Chapter 9 of this code.

4.4.4　The inspection and installation of valves shall comply with the related regulations of Chapter 7 of this code.

4.4.5　The safety valve installation shall be in accordance with the following requirements:

1　Except particular regulations by the equipment technical documentation，the disassembly checking should not be carried out；when installation，guarantee the correctness of medium flow and discharging direction，the regulation direction shall be convenient to operate；

2　Before installing safety valves，the pressure and the tightness shall be adjusted and regulated，carry out locking or leading sealing to the qualified safety valves；

3　The regulation and adjustment of boiler safety valves shall meet the relevant requirements of the current professional standard Boiler Safety Technical Supervision Administration Regulation TSG G0001.

4.4.6　The installation of de-ashing rapping system shall be in accordance with the following requirements:

1　The auxiliaries of de-ashing rapping system shall be completed，whose specification and type shall comply with the regulation of design documentation；

2　The moving parts are flexible；

3　Rapping test can be carried out after the installation of de-ashing rapping system is finished.