Preheating in Welding Induction Heating Systems

Heating Equipment

Induction Heating

The right system for your heating needs

Why Induction Heating?

Induction heating is easy to set up, offers a fast time-to-temperature, and delivers exceptional heating efficiency, accuracy, and uniformity in part temperature. In addition, induction offers safety benefits compared to open flame and resistance heating methods.


  • Preheating and maintaining weld temperature
  • Hydrogen bake-out
  • Post-weld heat treatment (PWHT) up to 1450° F
  • Shrink-fit processes
  • Various other applications which requires heating


  • Oil and Gas
  • Structural
  • Power plants
  • Petrochemical/Refineries
  • Process/Power Piping
  • Pressure vessels
  • Shipyards
  • Mining

Plate Induction Heating

Infrared Plate Induction Heating
This highly efficient technology uses non-contact heating to induce heat electromagnetically rather than using a propane torch or resistant heating.  With induction, the part becomes its own heating element, heating from within.  This makes induction very efficient since little heat is lost in the process.
Time to temperature is dramatically faster than flame or resistance heating -- reducing cycle time. Setup and tear down times are quick and unlike flame or resistance, induction allows continuous heating and fabrication.
Induction heating lowers operational costs because reaching target temperatures is dramatically faster, resulting in reduced consumable costs and labor expenses. In addition, it eliminates the expense of fuel gases, fire watch personnel, and heating subcontractors.
Quality IconProvides exceptional joint temperature uniformity.  Induction eliminates the inconsistencies and quality issues associated with flame or resistance heating.
Welders are not exposed to open flame, explosive gases, and hot elements associated with flame and resistance heating.  Induction’s method of heat transfer results in a cooler environment that reduces operator fatigue and improves work conditions.  

Compare Induction, Flame and Resistance Heating Methods

20 minutes or less per joint. Teardown time is fast, as induction tools can immediately be moved to the next joint without cooldown time.
Approximately 3 hours per joint. Teardown times are also lengthy, as crews must first wait for the heating equipment to cool.
20 minutes or less per joint
Up to 3 hours, depending on part/material size and thickness
Up to 3 hours, depending on part/material size and thickness
Thorough and even heat profile
Subject to hot and cold spots
90% efficient
Much heat lost to air; reheating needed after breaks and off hours
Marginal heat lost to air
Tools do not heat up; no toxic byproducts or noise
  • Risks burn injuries, fires and explosions
  • Excessive noise levels
  • Toxic, combustible byproducts
  • Ceramic pads are as hot as the work surface, bringing risk of burn injuries
  • Damaged/incorrectly used heating tools bring risk of electric shock
  • Inhaling insulation fibers/particles is a health hazard
  • Delivers strong return on investment
  • Electricity cost: $5/hr
  • Induction air-cooled cables and air-cooled quick wraps are ruggedly constructed for repeatable uses
  • Fuel cost: $50/hr
  • Fire-watch personnel must often be hired
  • Preheating contractors can charge up to $2,000 per joint, and final project costs often exceed original bid pricing
  • Requires installation of electrical infrastructure
  • Ceramic pads require frequent replacement
  • Used insulation is considered hazardous waste; proper disposal is costly

When Preheating Before Welding, How to Choose the Right Equipment

Air-cooled cables, a new heating tool for induction, deliver flexibility and efficiency for welding preheat.
Read More

Induction Heating Cuts Preheat Time, Provides Localized/Uniform Heat Treatment and Documents the Process for Swartfager Welding, Inc.

Induction heating proves safer, faster and more efficient than other heating methods such as a torch or an oven for Pennsylvania fabricators.
Read More

Welding Preheat Time Reduced in Lambeau Field Structural Steel Project

Induction heating delivers more consistent heating while improving productivity and safety in structural welding applications.
Read More

Miller's ProHeat™ 35 Induction Heating System Improves Preheat Time and Quality, Improves Productivity for Mechanical Contractor

Through induction heating Topp's Mechanical has found a solution that meets and exceeds the quality standards of its heat treatment applications while also providing strong operational benefits, including faster time-to-temperature, consistent heating throughout the entire part, easier to apply/wrap heat, greater reliability and lower consumable costs, more efficient use of labor, and improved...
Read More

Welding With Induction Heating Improves Consistency and Saves Time

Using an induction heating system for welding preheat and post-weld stress relief can save time and improve productivity.
Read More

The Pride of Big Prairie, Ohio

Pride of the Hills Manufacturing of Big Prairie, Ohio is largely sustained by what sits hundreds and thousands of feet beneath those hills: shale gas. Set in the heart of Marcellus and Utica Shale country, Pride of the Hills has grown with the region's shale gas production boom. As a manufacturer of oil and gas production equipment, the company has grown and evolved with increased production level...
Read More

Heat Parts Faster and More Consistently with Induction Heating

Induction heating provides great consistency in heating, faster time to temperature of the part, ease of use and safety in operation.

Miller Induction Heating - How it Works

This introduction to induction heating in welding applications will explain how it works and what it is.

Miller Induction Heating - Where it Works

Learn more about applications for induction heating.

Go Beyond Flame Heating: ProHeat™ 35 Induction Heating System

Flame means problems with temperature consistency and safety. Solve them with a Miller ProHeat 35 Induction Heating System.

The Lambeau Episodes 5: Induction Heating in Structural Steel Applications

Miron Construction used Miller induction heating throughout the Lambeau Field expansion project.

Topp's Mechanical: Induction Heating

Miller visits with Topp's Mechanical to discuss their use of Miller's induction heating technology in the ProHeat 35.

Induction Heating Cuts Preheat Time, Provides Uniform Heating for Swartfager Welding, Inc.

Swartfager Welding has turned to induction heating with ProHeat 35 for many of its preheating, interpass temperature control and stress relieving applications.

Induction Heating Proves Easy to Use for Topp's Mechanical

Miller visits with Topp's Mechanical to discuss their use of Miller's induction heating technology found in the ProHeat 35.

Topp's Mechanical: Induction Heating and Welding P1 Headers

Miller visits with Topp's Mechanical to discuss their use of Miller's induction heating technology found in the ProHeat 35.