Preheat, post-weld heat treatment, hydrogen bake-out and refractory dry-out — in the shop or on the unit — run to the code of construction, with every thermocouple on a calibrated chart and the inspection to close it out.
Heating that the code, the welder and the inspector all agree on — one team, one record.
Stress relief of welds and repairs to the code of construction — ASME VIII UW-40 / UCS-56, B31.3 para. 331, B31.1 para. 132 — with hold temperature, time at temperature and heating / cooling rates set from the P-number and thickness, not from habit.
Preheat held and verified before and during welding per the WPS and the code, so the procedure that was qualified is the procedure that gets welded.
Low-temperature soak of in-service steel before welding or repair to drive off dissolved hydrogen and prevent cracking — planned from the service and the material, recorded end to end.
Controlled dry-out and cure of new or repaired refractory in fired heaters, reactors and transfer lines per the refractory manufacturer's schedule, with the API 936 inspection alongside.
Local circumferential heat treatment of piping welds with the soak and gradient bands worked out for the joint, including the tight windows chrome-moly and P91 demand.
Heat treatment for NBIC and API 510 / 570 repairs and alterations, with the PWHT record ready for the R-stamp or the inspector's file.
How the heat is put in, how it is controlled, and what the record has to show.
Ceramic-pad heaters in controlled zones for local PWHT, preheat and bake-out — the workhorse for piping welds, nozzles and vessel seams.
Fast, even heating of thick-wall piping and heavy sections where uniformity through the wall matters.
Insulated enclosures and gas burners for whole vessels, headers and skids that cannot go to a fixed furnace.
Thermocouples attached where the code says, control and monitor points separated, calibrated chart recorders with the traceable record on every cycle.
A heat-treatment procedure for each job: material and P-number, thickness, hold temperature and time, rates, soak and gradient bands, thermocouple layout — signed before the first pad goes on.
ASME VIII (UW-40, UCS-56), ASME B31.3 (331) and B31.1 (132), ASME IX (QW-407), AWS D1.1 preheat, NBIC Part 3 for repairs, API 510 / 570 for in-service, API 936 for refractory. The edition invoked by your contract governs.
Hardness checks and the post-PWHT NDT the code or the client requires — done by the same team, attached to the same record.
Every cycle closes with the chart, the thermocouple map, the procedure and the sign-offs in one package — the page the inspector and the auditor actually ask for.
Four rules, kept on every job. They are why the reports hold up.
Every temperature in the record traces to a thermocouple on a calibrated recorder. If it was not measured, it is not on the chart.
Hold temperature, time at temperature and rates come from the code of construction, the P-number and the thickness — never from what worked last time.
Preheat, interpass and PWHT are essential variables of the welding procedure. We run what the qualified procedure says, and the record shows it.
Every cycle and every hold point carries the name and time of the person who did it. A cycle is either closed with its chart or it stays open, on the list.
A heat-treatment package you can hand to the inspector, the AI or the auditor.
| Procedure | code · P-No · thickness · cycle |
| Thermocouple map | control & monitor points |
| Chart record | calibrated · every cycle |
| Hold & rates | as run vs. as required |
| Hardness | after treatment, where required |
| Post-PWHT NDT | attached to the weld |
| Deviations | listed, dispositioned |
| Sign-offs | name and time, every one |
The same AssetSentry™ record system our inspection side runs on — so the heat-treatment package lands next to the weld it treated.
Tell us what you have — a repair that needs PWHT, a heater going back on line, a shop with a stress-relief backlog, a P91 weld — and we will come back with a cycle and a price.
Oklahoma-based. The heat-treatment side of an inspection team led by an API certified inspector. PHD Consulting, Inc.