Furmanite On-Site Field Post Weld Heat Treatment (PWHT) services are used frequently in the following applications.

• Pressure Piping
• Boiler and Vessel Repairs
• Nozzle Installations
• Caustic Service Piping
• Caustic Service Vessels

WHY USE POST WELD HEAT TREATMENT (PWHT)?

Post Weld Heat Treating Produces the following results:

Relaxation of Residual Stresses Relaxation of Thermal Stresses Tempering (Softening) Removal of Diffusible Hydrogen

POST WELD HEAT TREATMENT (PWHT) AND TEMPERING (SOFTENING)

Tempering Welds Improve Weld Characteristics including:

Resistance to Brittle Fracture by Producing a more ductile and stronger weld and Heat Affected Zone Minimize The Risk H2S Stress Cracking & Other Failures Created by Equipment Being in Harsh Service Environment, Such as: Alkylation Units Caustic Service

POST WELD HEAT TREATMENT AND RESIDUAL STRESSES

• Risk of Several Major Causes of Failure:
  • Brittle Fracture
  • Stress Cracking
  • Corrosion Cracking
  • Fatigue
• Tensile Residual Stress Can Act Alone or Interact With Service Stress To Promote Cracking.
• Dimensional Stability after Machining is increased.
  • Internal stress imbalance is eliminated

FURMANITE HEAT TREATMENT ENGINEERING SERVICES

Furmanite provides the following heat treatment engineering support services:

Structural Integrity Analysis Tower weight and wind load analyses per ASCE Bullet saddle support per Zick Analysis Heat Transfer Analysis Pipe flow heating thermal power requirements Temperature gradient determination Thermal finite element analysis (FEA) Vessel/pipe thawing power requirements Vessel heating thermal power requirements Engineered Thermal Process Procedures In accordance with ASME / API / AWS / NBIC / AAR codes AutoCAD drawings of thermocouple and heater location Custom procedures per client requirements Custom Equipment Design and Manufacture Gas combustion furnaces Electric resistance furnaces Multi-zone power and control (PLC) consoles