Pre and Post Weld

Furmanite’s Pre and Post Weld Heat Treatment Services

With over 75 years of developing cutting edge technology, Furmanite is a name you can trust for all of your on-site engineered service needs. We have developed the most sophisticated and reliable Heat Treatment Equipment available for your next Pre or Post Weld Heat Treatment (PWHT) project. Combine our advanced equipment technology with the best trained and most knowledgeable Heat Treatment Technicians in the field today and you have a winning combination that delivers quality results on time and under budget.

On-Site Field Heat Treatment Technology

Furmanite Pre and Post Weld Heat Treatment (PWHT) equipment and services offer the following advantages:

• Reduced Manpower Requirements
• Safe and Sophisticated Record Keeping
• Improved Reliability
• Meets Welding Code Requirements
• Stress Relieving will minimize Weld Cracking, fatigue, and failure
• Temper Welds to improve ductility and minimize hydrogen sulfide stress cracking
• Remove Hydrogen from Welds to decrease the possibility of HAZ and / or weld metal cracking

Local Pre and Post Weld Treatment Services

With over 1400 employees and 70 field operations offices located across 6 continents, Furmanite has the ability to meet all of your pre and post weld heat treatment needs. Our highly skilled technicians and advanced technology equipment are available for deployment in your area. We pride ourselves on providing the highest level of service and attention to detail that every project deserves.

Furnanite Quality Assurance

• Furmanite is an NUPIC Approved 10CFR 50 Appendix B Supplier and is a member of the Nuclear Industries Assessment Committee (NIAC).
• Furmanite’s Quality Assurance Program consists of the following manuals:
• QA Manual to Nuclear & ISO 9000 format
• QA Procedures and Forms
• Standard Procedure Manual
• Training Program
• Measurement and Calibrations
  • NIST Traceable
  • NUPIC Approved Calibration Supplier
  • Onsite Pre & Post Calibration
• Procedures to applicable Industry Codes
• ASME BPVC Sections I, III, VIII and XI
• ASME B31.1 and B31.3
• API, NBIC

Furmanite’s capability

• High velocity combustion gas trains with variable output (100,000 to 10million BTUs per hour)
• Extensive Burner sizes available from ½ million to 10 million BTUs
• 15 gas trains manufactured to date
• We own and operate two furnace facilities Sulphur (Louisiana) 6’ x 6’ x 10’ Clute (Texas) over 40’ x 7’ x 7’
• We can build temporary furnaces around most structures and work pieces

Pre Heat treatment

Thermal stresses occur as molten weld pools cool at which point cracking can occur both during and after welding. Moreover, the colder parent or base metal resists the inevitable contraction of the weld metal. In some instances heavy wall materials and aluminum alloys with higher thermal conductivity can act as a heat sink, drawing heat away from a weld and cooling at an accelerated rate. If moisture is present at a welded joint, the high heat of the welding arc will break the water down into its elements, hydrogen and oxygen. The hydrogen by-product easily dissolves into the weld metal and causes weld porosity during weld solidification. During and after completing of the welding process, both the weld pool and the heat affected zone (HAZ) can harden and crack when cooling at a rapid pace. Pre heat treatment is used to prepare the base metal work area so as to improve the integrity of the weld or machining process by raising the temperature gradually thereby improving ductility in advance of the work taking place. This enables the higher temperature area to respond more effectively to the weld or machining process.

THE BENEFITS OF PRE HEAT TREATMENT

• Reduces the levels of thermal stress
• Compensates for high heat loss
• Minimizes the rate of weld hardening
• Reduces the porosity of the weld
• Reduces hydrogen cracking
• Improves micro structure of heat affected zones

Post Weld Heat treatment (PWHT)

Welding and machining induces changes in the chemical/mechanical properties of the base material which could result in distortion, cracking and misalignment (of precision machined holes, for instance). To minimize this affect, controlled heat treatment is undertaken to lower the temperature gradually over a defined period to reduce the stress within the heat affected zone as well as the area immediately adjacent to it, thereby reducing metal hardness and improving ductility across the worked on area. By uniformly heating the base metal (pipe, vessel, etc) to a sufficiently high temperature, just below the metal transformation temperature range, then reducing the temperature over a prolonged, controlled period (dependent on material thickness), the base metal can return to the normal operating temperature and the pre-stressed state.

THE BENEFITS OF POST WELD HEAT TREATMENT

• Relaxes residual stresses
• Relaxes thermal stresses
• Tempers the metal
• Removes diffusible hydrogen
• Metallurgical structure is improved
• Strength and life of the material is enhanced

Pre and post weld treatment has a role to play in normalizing pipes, pressure vessels, reformers, boiler headers, boiler heater tubes, steel mill rollers, furnaces and other critical plant and equipment. It is of particular benefit in start-ups following outages, stabilizing welding and mechanical work. 

Combustion

Furmanite’s Combustion Heat Treatment Services

With over 75 years of developing cutting edge technology, Furmanite is a name you can trust for all of your on-site technical service needs. We own and operate the most advanced and dependable fleet of Heat Treatment Equipment available for use in the field today. Combine our advanced equipment technology, the best trained and most knowledgeable Heat Treatment Technicians, and strategic locations of our field service centers and you have a combination that delivers quality results on time and under budget.

On-Site Field Heat Treatment Technology

Combustion Services and Refractory Dry Outs

• Refractory Dry Outs Give Your Linings
• Improved Refractory Strength
• Refractory Separation Eliminated
• Removal of Mechanical Water
• Minimize Explosive Spalling
• Avoid Thermal Stress

Improved Refractory Strength

• Near 1000 Degrees F Ceramic Bonding Takes Place.
• High Velocity Burners Apply High Pressure and Heat
• This Ensures Cross-Sectional Ceramic Bonding.
• Increasing Refractory Strength, Resulting in Increased Service Life.

Refractory Separation Eliminated

Proper Dry Out Ensures That Dual Component Linings Will Not Experience Sagging or Separation from Anchored Refractory By:

• Utilizing hot, cold, and intermediate thermocouples.
• Ensures proper through wall temperature gradients.
• 1000 degrees f, ceramic bonding takes place.

Removal of Mechanical Water

Refractory Heated too Quickly or Unevenly May:

• Lock moisture in, causing shortened refractory life.
• Proper Dry Out
• Removes mechanical water at closely controlled temperatures below 600 degrees F.

Minimize Explosive Spalling

Controlled Dry Out Will:

• Slowly & safely, force mechanical and chemical water from
• the refractory lining.
• Avoiding pressure buildup and explosive spalling.

Avoid Thermal Stress

Controlled Dry Outs Prevent

• Minute cracking
• Thermally induced stress which weakens the refractory.

Industries Requiring Refractory Dry Outs

• Steel Mills
• Aluminum
• Foundry
• Glass
• Cement
• Ceramic
• Refineries
• Chemical Plants
• Power Plants