Diff-Therm Platen Heaters for Vacuum Diffusion Pumps

28 Hayward St., Ipswich, MA 01938
Tel: 1-978-356-9844, Fax: 1-978-356-9846
www.DaltonElectric.com

We are an authorized distributor for Dalton Electric Heating Company, Inc., who began manufacturing Diff-Therm Diffusion Pump Heaters in 1958. Today, Diff-Therm heaters are the replacement heater of choice for vacuum OEM diffusion pump users.

The Diff-Therm heater is a combination of high-quality, tubular heating elements and grey iron castings (platens and rings) swaged together under 50 tons per square inch pressure. For over twelve years of service to the vacuum industry in the United States and Canada, these heaters have been the industry standard for long life, for uniformly distributed process heat, and for efficient power generation.

Dalton Electric Heating manufactures stock Diff-Therm heaters for 2" through 48" Diffusion Pumps in over 100 combinations of electrical ratings and casting sizes. They also manufacture Diff-Therm heaters in custom casting dimensions and electrical ratings for use on obsolete and foreign-made pumps.

In summary, Diff-Therm heaters provide you with...

• Easy heater selection;
• Timely deliveries;
• Easy installation;
• Superior process heating;
• Longer heater life.

They are the proven, industry standard.

Illustrations 1 and 2 below tell the story of Diff-Therm's performance superiority over other, bolt-on Diffusion Pump heaters. Dalton manufactures tubular heating elements using only high purity magnesium oxide, nickel chrome resistance wire and stainless steel terminals for internal components. Special filling equipment and methods compact the magnesium oxide inside and around the resistor helix to extreme density which, coupled with swaging, gives Diff-Therm heating elements high dielectric strength and efficient internal heat conduction. These properties are then maximized as the heating elements are further compacted by being swaged into undercut grooves in the Diff-Therm castings. This process locks the heating elements into con-tact with the castings, creating uniform heat conduction into the castings along the entire length of the grooves.

The surface of a Diff-Therm casting, which will be in contact with the Diffusion Pump boiler plate, is machined to a flat, smooth finish. When the assembled heater is bolted onto the Pump, heat is conducted efficiently and uniformly into the boiler plate for a steady vaporization of the Pump fluid.

Illustration 1

Illustration 2

Selection Chart:

	Platen Number 2/9D		Platen Number 4D		Platen Number 5D
	Platen Number 3/2D		Platen Number 4/2D		Platen Number 5/5D
	Platen Number 3/3D		Platen Number 4/9D		Platen Number 6D
	Platen Number 6/5D		Platen Number 7/3D		Platen Number 10R
	Platen Number 6/9D		Platen Number 8R		Platen Number 10/9D
	Platen Number 7D		Platen Number 8/2R		Platen Number 11D
	Platen Number 12D		Platen Number 15R		Platen Number 12/3 RI (typical)
	Platen Number 14R		Platen Number 16/8R

Selector Index:

1. Dill-Therm Heaters originally designed for Diffusion Pumps of these manufacturers.
2. Radii listed above are measured between apex of the angle formed by extending Platen sides to a point and outside edge of Platen (see illustrations).
3. "Inside" and "Outside" relate terminal locations to the Platen perimeters. The angles listed are between the terminals and the surfaces of the Platens.

Copyright © 1997-2001 Dalton Electric Co., Inc. All Rights Reserved. Used with permission of Dalton Electric Co., Inc.