DB(GC) SiC heating elements
Description:
Type DB Dumbbell - (Enlarged Cold End) - Silicon Carbide SiC Heating Elements One of the earliest heating element designs, the enlarged cold ends of the DB type SiC heating element were originally made oversized to increase cold end. One of the earliest heating element designs, the enlarged cold ends of the DB type SiC heating element were originally made oversized to increase cold end cross section, lowering electrical resistance, thereby lowering cold end operating temperature. Modern DB by contrast, employ an advanced technology to keep the terminal ends cool by virtue of the decreased resistity of the lower resistance cold end material used in the manufacturing process. Oversize cold ends are therefore no longer necessary. DB SiC heater can be substituted for Dumbbell STA. The old style resistance ratio was 1:3, whereas the new DB SiC heater resistance ratio is 1:15. Maximum temperature is 1600 deg C.
One of the earliest heating element designs, the enlarged cold ends of the Dumbbell style element were originally made oversized to increase cold end cross section, lowering electrical resistance, thereby lowering cold end operating temperature.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 DB SiC heater, 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. Non-dumbbell (ED type) can be substituted for Dumbbell SiC heater. lmprovements in the cold-end-to-hot-zone resistance ratio between the original DB and new DB SiC heater have been dramatic. The old style resistance ratio was 1:3, whereas the new DB and ED resistance ratio is a minimum of 1:15.
The first several inches of the cold ends are metalized with aluminum to provide a low-resistance contact surface. Electrical connections are made using flat aluminum braids, held in compression to the cold end circumference by stainless steel spring clamps.
DB SiC heater are described by giving the overall length, the heating section length, the hot zone outer diameter and the cold end outer diameter. 
