The hallmark of NVI’s approach to heat treatment is flexibility. We can provide heat treatment onsite as well as offsite. Thanks to the strength of our engineering staff, we can combine both approaches, designing customized solutions offsite for deployment onsite. This flexibility can save clients time and money.
Welding is a prime source of residual stress in metals because it induces rapid thermal expansion and contraction in a localized area. It is important to relieve residual stress because it reduces the fatigue life of the metal and can cause buckling and stress corrosion cracking. This is particularly dangerous in situations when the metal is subsequently exposed to high temperatures and pressures.
The most common way to relieve residual stress is through post-weld heat treatment. This entails heating the weld, holding it at temperature, and then following with controlled cooling. This process helps return the metal to its original grain structure, making it more flexible and ductile.
NVI performs on-site heat treatment services with furnaces ranging from 4 feet to 46 feet and localizing units up to 24 zones – expandable upon request. Units are fully self-contained with quite pack generation. Heat treatment services include pre-heating, post weld heat treatment, annealing, hardening, refractory bake out and quenching.
- Mobile Onsite Capabilities
NVI’s self-contained mobile units are generator-powered and include all control equipment, enabling us to perform heat treatment services anywhere. In cases where there is a high density of welds, we can also transport small furnaces or bring furnace panels onsite and bolt them together in the most appropriate configuration. These approaches, which rely on NVI’s offsite engineering capacity, can substantially reduce a client’s inspection costs.
- Offsite Furnaces
For clients, the most cost-effective option is to bring their welds to NVI facilities where there are permanent heat treatment furnaces. We can also create custom furnaces for clients onsite.