Compact High Frequency Welder - Inductotherm Group India

Compact High Frequency Welder

The Thermatool Compact Solid State Welder provides a great solution for those older tube mills with limited tube diameter ranges while benefiting the producer in terms of reliability, compact layout, safety and supportability. This simplified and compact design fits the traditional DC power supply into the RF Generator cabinet, making this welder the logical choice for a cost effective installation. The Compact welder is ideal for quick retrofitting on existing mills when replacing obsolete vacuum tube welders. All the reliability of a standard Thermatool CFI Solid-State HF Welder, with a small footprint.

As the only global induction heating and welding manufacturer specializing in tube and pipe welders, Thermatool provides the widest range of HF Welders available.

All of our welders are based on the High Frequency or “HF” welding process that we developed almost 60 years ago and have led the way ever since. With its Current-Fed Inverter (CFI) design, our welding equipment range gives you the capability to successfully weld almost any metal you want – efficiently and economically.

We supply equipment needed to weld carbon and stainless steel, brass, copper, and aluminum, as well as exotic alloys, such as boron steel and HSLA, AHSS, and Trip Steels.



Plot No. SM-6, Road No.11 Sanand-II, Industrial Estate, BOL Village, Sanand Ahmedabad- 382170


  • Simple compact design with a small footprint. Ideal for quickly retrofitting or for existing mills when replacing older vacuum tube welders.
  • High-frequency, high-power capacitor bank delivers stable power with safer low voltage to minimize arc-overs and enhance reliability.
  • Fully equipped with a low ripple DC filter that produces a smoother output. This results in high quality welds with minimum ID and OD weld beads reducing wear on scarfing tools and downtime.
  • Ideal for limited OD range tube with induction capability up to 300 kW.
  • Short circuit proof CFI power supply technology ensures reliable operation through coil arc-overs and minimizes trip-outs.
  • Water-cooled, high frequency module pairs minimize total power loss and reduces time required for maintenance. Compact, efficient and rugged high output MOSFET power modules cleanly convert DC voltage to high frequency AC voltage.
  • Utilizes nearly all of the same components as the industry standard CFI model. Parts are stocked and available immediately.
  • Protective cover keeps weld leads clean of mill scale and welding debris. All doors are completely sealed with high quality gaskets, thus eliminating contamination.
  • Doors are fitted with lift-off hinges for easy access.
  • Available with Thermatool induction coils or contact assemblies providing the highest reliability, energy efficiency, highest yield and uptime.

Tech Specs

Power Range Up to 300 kW
Output Frequency 300 kHz + 15%
Diameter Range Limited (0.5-5”) OD
Induction Coils Standard
HF Contact Welding Yes
Dual Induction Contact No
Weld Tables Single, 2, 3
AutoMatch™ Electronic
Speed Power Control Yes
Tachometer Upon request
Efficiency > 85%
Power Factor 0.95
Ripple ~2
WeldScan No
ThermaView No
ThermaSure No


Induction Coils
Thermatool offers a comprehensive range of induction coils, designed specifically for use with Thermatool solid-state HF induction welders. Manufactured from high conductivity copper, quality inspected and coated for long life, there are numerous types and sizes available to satisfy every application. Many of these models are available for immediate delivery from stock.

Whether you are producing carbon steel, stainless steel, copper, brass, aluminum or galvanized tubing, Thermatool has the induction coil to meet your specific needs. Our comprehensive range of induction coils fully supports the entire range of Thermatool welders with power ratings from 50 kW to 2 MW and operating frequencies ranging from 150 kHz to 800 kHz and variable frequency.

For special coil requirements, Thermatool engineers are pleased to review the possibility of a custom coil design/build.

Thermatool offers an extensive range of impeders to satisfy a very diverse range of tube and pipe welding applications. Whether your mill produces small diameter/thin wall tubing or large diameter/heavy wall API line pipe, Thermatool supplies a complete selection for you. The proper choice of impeder, correctly installed, will play a major part in achieving maximum welding efficiency. It should also be noted that as the performance of all ferromagnetic materials is a function of temperature, it is critically important that the ferrite core is kept as cool as possible during the tube welding process. Ideally, the temperature of the coolant flowing through an impeder should not exceed 25°C. Thermatool also supplies booster pumps for these demanding applications.

Modern tube mills that operate at higher line speeds have created demand for impeders that deliver superior performance. Such enhanced performance can only be achieved by using the very best ferrites available. A growing number of tube and pipe producers worldwide choose Thermatool ferrites in order to optimize the performance of their mills. Thermatool offers four different types of ferrites which can be cut to length, if required. Contact us today to learn more!