These systems require very high-quality weld joints, with emphasis placed on obtaining a smooth inside surface to avoid contaminant traps and on all the normal structural requirements for welded joints. Stainless steel, such as 316L, is used to provide corrosion resistance against attack by the process chemicals or the cleaning procedures. Specifications for the exact tolerances to be applied to tubing for fusion weld end preparations have not been universally accepted and are, in general, established by in-house welding procedures.
Allowable burr depends on the welding procedure and the specific application requirements.
When deburring is allowed, care must be taken to avoid generating chamfers on either the ID or OD of the tube, which can cause excessive suck back in the weld zone. Advantages and disadvantages of the procedures and the machine tools are as follows. Part Off Cutting. This is for very flat and square ends with precise bevel angles. Achieving a burr-free cut on the ID of the tube is difficult without a second operation.