This standard specifies the technical requirements for manufacturing the finned tubes (panels) by welding plain tube and flat steel.
This standard is applicable to the fabrication and inspection of the finned tubes (panels) welded with plain tube and flat steel along the longitudinal direction.
The reprocessing of finned tubes (panels) afterward, such as their fabrication and their assembling with the header tank, all shall be fabricated and inspected according to the relevant regulations specified in their relevant standards.
2 Normative References
JB3375 "Receiving Acceptance of Materials for Boiler Construction"
JB1612 "Technique specification for Hydraulic Test of Boiler"
JB/T 1615 "Technique Specification for Painting and Packaging of Boiler"
JB 1611 "Technical Specifications for the Manufacturing of Boiler Tube"
JB 4420 "Welding Technique Evaluation of Boiler"
JB 1613 "Welding Technique Specification for Boiler Pressure Parts"
3 Technical Requirements
3.1 The adoption of the materials of tubes and flat steel for manufacturing finned tubes (panels) shall be in accordance with those specified in the relevant technical documents as well as the requirements of the design drawing. The materials must go through procedures according to the relevant regulations.
3.2 The steel tubes and welding materials used for manufacturing the finned tubes (panels) must be inspected by the inspection department according to the relevant regulations specified in JB 3375, and those non-inspected materials or rejected one in the inspection shall not be put into production.
3.3 All the flat steel used for manufacturing finned tubes (panels) must be with the material quality guarantee (or material quality certificate).
3.4 The splicing of the tubes used for manufacturing the finned tubes (panels) shall be in accordance with the relevant regulations specified in JB 1611.
3.5 Before welding, the surface of the steel tubes and flat steel shall be cleaned off the oil stain and rust, and their mutual welding positions must be clean and bright.
3.6 The tubes and flat steel must be carried out with qualification of welding procedure (the ratio-frequency welding must be with Welding Procedure Specification) according to the relevant regulations specified in JB 4420 before the welding, and those accepted ones can be welded.
3.7 The welders who have passed the relevant examination are able to take in charge of the welding work of finned tubes (panels); the expert technicians shall take in charge of the welding work when adopting the ratio-frequency welding, and they shall implement the welding procedure specification strictly in operation and note the duty records as required.
3.8 The defects on individual finned tubes (panels) shall be repaired by qualified welders with manual electric arc welding according to the rewelding procedure that is qualified through evaluation.
