Stainless steel pipes for regenerative thermal oxidizer – RTO facilities at Exxon Mobil. The material is certified and PMI-tested (Positive Material Identification) on account of the refinery industries’ extremely rigid requirements for documentation, traceability and inspections. All welding is carried out under welding procedure specifications and qualifications. Non-destructive testing and approvals are done by TÜV, MTL and DEKRA.