Regarding the welding scope for the welder certification program.

Based on the information you provided, the welder holds a certificate for GTAW (Gas Tungsten Arc Welding) – FeⅣ-6FG-12/57-Fefs-02/10/12. This information indicates the welder’s welding techniques, materials, location, and other details. - GTAW refers to gas-tungsten arc welding, which is a common welding method suitable for many different types of materials. - FeⅣ: This should refer to the material used for welding; Fe generally denotes iron or carbon steel. - 6FG: This should refer to the welding position; 6FG generally denotes vertical upward welding and horizontal welding. - 12/57: This might be the welding parameters or specifications. - Fefs: This might refer to the type of workpiece or structure being welded. - 02/10/12: This may refer to other welding parameters or specific requirements. Overall, welders do indeed possess the ability to weld iron or carbon steel materials vertically upward and horizontally. However, whether it is possible to weld the fillet welds between the heat exchanger and the tube sheet, as well as the suitability of the 19*2/25*3 specification, needs to be determined based on actual process requirements, welding locations, and welding parameters. I suggest that you consult specific welding technicians or refer to relevant welding specifications and standards to make a decision. .

Referencing this table, the rated diameter is 57, with the minimum diameter for welded parts being 25; therefore, a diameter of 19 is outside the specified range.

The outer diameter of the welded 19-inch pipe is as shown in the diagram above; it involves a welding task for pipes with a small diameter. Also, this certificate applies to iron and stainless steel; for those workpieces with specifications of 19 or 25, the material category must also be the same

The weldable specification range is on Floor 3, and the materials are on Floor 4.

The welds between the heat exchange tubes and the tube sheet are fillet welds, so they are completely suitable

TSG Z6002－2010 Detailed Rules for Assessing Welders of Special Equipment: For low-carbon steel FeⅠ, low-alloy steel FeⅡ, chromium-molybdenum steel, ferritic steel, martensitic steel, as well as austenitic steel and austenite-ferrite duplex steel FeⅣ, except that FeⅣ cannot be replaced, welders qualified to work with materials of a higher grade can also weld materials of a lower grade. The test pieces are applicable to welds and weld locations of welded components. The tube sheet corner joint test piece 6FG can be welded in all positions; welding is possible as long as the welding method and material remain consistent. However, for tube sheet joints made of the first three materials, manual arc welding cannot be used for welding. For details, see TSG Z6002－2010 Guidelines for the Assessment of Welding Operators for Special Equipment

6FG is 45-degree tube sheet welding