Isothermal Furnace Liners


Design Flexibility

can be fabricated for sub-ambient and cryogenic operation


Extremely Reliable

provide a uniform temperature working environment


Cost-Effective and Simple to Install

no moving parts

Isothermal Furnace Liners (IFLs) are ring-shaped liquid metal heat pipes that provide a uniform temperature working environment. IFLs from Boyd Corporation save time and energy while maximizing productivity, by achieving isothermal wall temperature. With no moving parts, the IFL is simple to install, provides design flexibility and is extremely reliable and cost-effective. Unlike probes, the IFL does not depend on heat transfer paths connecting to surrounding walls or the outside environment.

In most applications, Boyd IFLs provide a single uniform temperature zone using a single heater and controller. For multiple, individually controlled zones or step changes in temperature profile, two or more IFLs may be used in series. Temperature adjustment is a simple one-step process and frequent profile measurements are not necessary.

The superior temperature uniformity provided by Isothermal Furnace Liners is required in exact processes such as semiconductor crystal growth, thermocouple and temperature calibration, vapor deposition, black body radiators, concentrated solar receivers and more. IFLs are well suited for process tubes and laboratory furnaces in chemical processing and research applications. Measured spatial temperature variation in an IFL is less than 10mK and in many cases may exceed the sensitivity of available measurement techniques.

Standard IFLs for operation to 1,600°C are available in a range of sizes to fit conventional furnace bores for horizontal or vertical application. Custom IFLs can be fabricated for sub-ambient and cryogenic operation. The size and geometry of the IFL can be customized to any application.

The Isothermal Processing Vessel (IPV) is an extension of the Isothermal Furnace Liner, which has been supplied to semiconductor crystal growers and calibration laboratories since 1971.

Request a Quote

Key Industries


  • Semiconductor Crystal Growth
  • Vapor Deposition
  • Thermocouple and Temperature Calibration
  • Equipment Calibration Laboratories
  • Read More…


  • Concentrated Solar Receivers
  • Black Body Radiators
  • Read More…

    Related Products

    Have questions? We're ready to help!