Underheated Furnace Technology Increases Foundry Efficiency


Pyrotek's Michael Machado and Tomáš Mazálek working with a furnace operator at PUNCH Powerglide foundry in Strasbourg, France.

With hundreds of installations in both low-pressure and high-pressure applications, Pyrotek's underheated holding furnaces help foundries around the world meet the market and customer demands for higher quality metal. It’s a technology Pyrotek advanced; understanding the need for higher metal quality to make lighter and thinner castings for aerospace, automotive, and other industries where strong, light-weight parts are critical. We also recognize the never-ending pursuit of reduced operational costs.

“We understand the current state and the future of aluminium casting and the requirements for lighter and thinner castings, resulting in the need for high metal quality,” says Dusty Ousley, Pyrotek’s US Foundry Division Sales Manager. “We also know the demands to reduce operational costs.”

Standard underheated furnaces, with submerged heating elements, deliver valuable benefits such as a 25–30 percent reduction in energy consumption compared with top-heated designs.

Top-mounted heat elements create higher atmospheric temperatures in the holding chamber, resulting in oxide generation. A thick oxide layer insulates the top of the bath, not allowing the heat to transfer to the metal properly. This increases the temperature of the heating elements and decreases furnace energy efficiency. Additionally, the resulting oxide growth will damage the furnace body and heating elements.


Pyrotek underheated furnace in use at PUNCH Powerglide.

“The underheated design offers greater metal cleanliness due to reduced oxide generation,” Ousley says. With a heat source fully immersed oxide production is minimized in the holding chamber.

Another advantage of Pyrotek’s underheated holding furnace is it takes up less space, which leads to energy savings.

“When horizontal underheating is used, a smaller overall footprint can be used,” Ousley says. “This allows for reduced floor space and aluminium surface area, resulting in less exposure to open air and less oxidation of the surface.”

A smaller exposed surface area results in more homogenous metal temperature throughout the entire bath.

“Overall, this results in energy savings,” he says.

Underheated furnaces also ensure versatility for use in gravity, low-pressure, and high-pressure applications.

Furnace7 blur

Pyrotek underheated furnace at GIFA 2019.

Technology Advantages

  • Reduced maintenance and lower operational costs
  • High-quality alloy
  • More accurate regulation of alloy
  • Efficient conductive heat and promotion of convection currents
  • Filtration and degassing capability
  • Minimal aluminium-oxide buildup on furnace walls
  • A 6− to 8−year service life

Specific Pyrotek Benefits

  • Further energy savings
  • Experienced engineering and maintenance teams positioned globally
  • Turnkey delivery possible, including casting machine with partner companies
  • Heater elements with extended service life
  • High-quality thermocouples
  • Smaller footprint on plant floor
  • Safe working environment

INFOGRAPHIC: The drawings below depict different views and information regarding underheated furnace technology.

Gravity open Furnace top correctGravity open Furnace side

Low Pressure Furnace side

Posted in Insight Newsletter, Article.

Tags: Engineering Services, Foundry.