Starbar® Type RR
The Type RR is the standard Starbar® element. A high-density self-bonded silicon carbide element, type RR is available in a large range of diameters and lengths. This type of element is available in the following cold end types:
- One Piece RR -- The cold ends are impregnated with silicon metal to reduce their resistance. This type is highly stable at temperatures up to 1700°C (3100°F).
- Three Piece RR -- Features welded-on low resistance cold ends (LRE) which run cooler than any one-piece cold ends. Therefore, they are more energy efficient. Maximum temperature 1425°C (2600°F)
Starbar® Type TW
The type TW element is a higher density element, used in a corrosive atmosphere or where normal RR type elements do not provide acceptable service life. The TW element has a density 10 to 12% higher than normal RR elements. This higher density results in slower oxidation and aging, which yields longer element life. The dimensions and electrical properties of the TW element are similar to those of the RR element. Therefore, a TW element may be interchanged directly for an RR element. The TW element due to its higher density is more prone to thermal shock. Maximum temperature is 1425°C (2600°F).
Starbar® Type DB
One of the earliest heating element designs, the enlarged cold ends of the Dumbbell style element were originally made oversized to increase cold end cross section, lowering electrical resistance, thereby lowering cold end operating temperature. Modern Dumbbell Starbars®, by contrast, employ an advanced technology to keep the terminal ends cool by virtue of the decreased resistivity of the lower resistance cold end material used in the manufacturing process. Oversize cold ends are therefore no longer necessary. RR Starbars® can be substituted for Dumbbell Starbars®. The old style resistance ratio was 1:3, whereas the new DB and RR resistance ratio is 1:15. Maximum temperature is 1425°C (2600°F).
Starbar® Type RA
The right angle (RA) element has the electrical characteristics of the RR element. The cold ends are attached perpendicular to the hot zone. The horizontal portion is the hot zone. The RA is normally installed with the cold ends through the roof of the furnace. For maximum temperature up to 1425°C (2600°F).
Starbar® Type U
The U type Starbar® is manufactured by taking two carefully-matched SiC rods and uniting them with a silicon carbide bridge. These elements provide for wiring both terminals from one side of the furnace. Ideal for drop-through designs, radiant tube systems or where one element will not span the heating chamber. For maximum performance up to 1425°C (2600°F).
Starbar® Type W
Identical to the U type, except with three matched SiC rod sections for three-phase service. For maximum temperature up to 1425°C (2600°F).
Starbar® Type WDB - for Float Glass Production
Star performers in float glass production type W three phase Starbars® are comprised of high-purity, high-density, silicon carbide grains that are self bonded through recrystallization at elevated temperatures. Sintering at temperatures in excess of 2200°C provides a structural density of 2.50 grams per cubic centimeter. Such high structural density results in Starbars® of maximum strength and minimum porosity, with an extremely slow aging characteristic. For maximum temperature up to 1425°C (2600°C).
Starbar® Type SE
This high-density silicon carbide element is spiral-cut to increase the resistance of the hot zone. This element is designed for wiring at both ends. For maximum temperature up to 1650°C (3000°F).
Starbar® Type TSE
The TSE Starbar® has a thin wall construction and an internal diameter open from end to end. The large internal diameter makes this Starbar® useful for tube furnace applications. For maximum temperature up to 1650°C (3000°F).
Starbar® Type SER
This high-density double-spiral element is cut so as to place both electrical terminations on the same end of the element. They are supplied with the terminal assembly attached. Type SER Starbars® are used where furnace design or dimensions preclude wiring from both sides of the furnace. This type is ideal for blind holes and insertion in tubes. For maximum performance up to 1650°C (3000°F).
Starbar® Type TSR
This tube-type spiral-cut element features a thinwall construction. The element interior can be used as the furnace chamber. Similar to type SER, the TSR has a terminal assembly at one end. For maximum performance up to 1650°C (3000°F).
Starbar® Type SEU
This high-density element has both electrical connections on one end. The hot section and the cold end have a double slot cut along its length. The cold end is larger in diameter than the hot section therefore it operates cooler. This element can be made in longer lengths than the SER Starbar®. The resistance values range from the RR type element of equivalent size to the SER type. For maximum temperature up to 1650°C (3000°F).
Starbar® Straps
The braided aluminum terminal straps are available in 25, 50, 100 and 200 amperage ratings. They are available in three primary styles.
Starbar® Clamps
Stainless-steel terminal clamps are used to hold the aluminum straps in contact around the circumference of the Starbars®. The aluminum strap and terminal clamp should be installed at the very ends of the Starbar®. Expansion tools are available for installation and removal of the T type clamps.
Starbar® Terminal Gasket Assembly
Terminal gasket assemblies, consisting of two ceramic fiber washers, one steel washer, and a spring can be used as an alternative to packing ceramic fiber insulation around the Starbar®.
Starbar® Terminal Tubes
Starbar terminal tubes are recommended to protect the furnace wall insulation and provide a constant clearance. Zircon and alumina tubes are available.
For more information, including detailed technical specifications, on Starbar® products, please contact us or visit I Squared R's Starbar® homepage.
