SGR(SCR,SEU) Type Silicon Carbide Heating Elements
SGR(SEU) type silicon carbide heating elements This high-density SGR double-spiral silicon carbide heating element is cut so as to place both electrical terminations on the same end of the element.
This high-density SGR(SCR) double-spiral silicon carbide heating 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. SGR (SCR) type silicon carbide heater is 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 can up to 1500 deg C.
Made of special high-density reaction-bonded silicon carbide, the SGR (SCR) double-spiral silicon carbide heating element is a tube with both electrical connections on one end. The hot zone is formed by cutting a slot, which reduces the cross sectional area over which the current flows, resulting in higher resistance than the cold end. The cold end is formed by cutting two longitudinal slots along the length of the tube and is made of LRE (low resistance end) material and in most cases is larger in diameter.
The SGR element is supplied with a ceramic collar cemented to the cold end. The cold end of the SGR (SCR) element is flame sprayed with aluminum for a distance of about two inches. Flat, braided-aluminum straps are held in compression with a stainless steel clamp to this metalized area. The clamp is electrically insulated from the flat braid with high temperature insulation. The aluminum braid is ten inches long and holes are provided for easy connection to the power supply.
The electrical resistance of the SGR(SEU) can be customized by varying the spiral width. SGR(SEU) double- spiral silicon carbide heating element can range from high resistance to low resistance. The electrical resistance can be as high as the SER (spiral element with return) and as low as the RR (rammed type) non-spiral double- spiral silicon carbide heating element. There are further limits based on the size of the SGR(SEU) .
SGR(SEU) double-spiral silicon carbide heating element are described by giving the overall length, the heating section length, and the diameter. As an example, SGR(SEU) 45 x 30 X 1-1/4 is a SGR(SEU) double-spiral silicon carbide heating element, 45" overall length, 30" hot zone, and 1-1/4" hot zone outer diameter. In metric, SGR(SEU) 1143 X 762 x 32 is a SGR(SEU) double-spiral silicon carbide heating element, 1143 mm overall length, 762 mm hot zone and 32 mm hot zone outer diameter. 
