Heat treatment is a process to achieve the required physical and mechanical properties for which the part will be used.. Heat treatment is a metallurgical application for relieving the stress after welding, hardening and softening the material according to requirement for its end use. There are many types of heat treatment processes that are in practice namely annealing, tempering and quenching, case hardening, precipitation hardening, post weld heat treatment, preheating etc.
Interface Technical Inspection has been providing all kind of heat treatment techniques as per the demand of the clients to meet their procedural requirements.
When welding some base materials and for some service conditions, preheating and/or post weld heat treatment may be a requirement. These types of thermal treatments are generally required in order to ensure suitable weld integrity and will typically prevent or remove undesirable characteristics in the completed weld. Any form of heat treatment is costly since it demands extra equipment, extra time, and extra handling. For these reasons, heat treatment should only be undertaken after careful consideration of the advantages it may offer. In certain cases heat treatment will be mandatory, as with heavy sections of low alloy steels, whereas in other cases, it will be a justifiable precaution against early failure in service.
Preheating During Welding provides the following benefits:
- Reduces the levels of thermal stress.
- Provides compensation for high heat losses.
- Minimizes the rate of weld hardening.
- Reduced porosity in the weld.
- Reduced hydrogen cracking.
- Improved microstructure of heat affected zone.
Post Weld Heat Treatment Services(PWHT)
Post Weld Heat Treatment Services is defined as the stress relieving method after welding to improve the mechanical and chemical properties of welds. There are different ways of performing PWHT like local heat treatment and furnace heat treatment. We have skilled and highly experienced personnel available to perform Heat Treatment.
Machining and/or Welding induce stresses in parts. The bigger and more complex the part, the more the stresses. These stresses can cause distortions in the part in long term. If the parts are
clamped in service,then cracking could occur. Also whole locations can change causing them to go out of tolerance. For this reason, stress relieving is often necessary.