Coil heaters and cable heaters are heating elements formed from straight, uncoiled segments of heating cable. Forming straight cables into patterns increases the surface area and heat transfer capability, but also requires increased energy and watt density. Most coil heaters and cable heaters operate on AC voltages. Some include a grounding wire or provide distributed wattage arrangements to concentrate heat distribution. Coil heaters and cable heaters can be configured with different termination options. For example, electrical connections can be made via a plug configuration and protected by a terminal box interface. Armor cable, metal braids, and flexible conduits are used to protect insulated leads.  

There are a variety of shapes and sizes for coil heaters and cable heaters. Some devices are straight, square, or rectangular. Others are round, coiled, spiral wound, or star wound. Spiral wound heaters are used to generate high temperatures in restricted areas. Star wound cables are offset coils inserted into pipes or ducts to create a turbulent flow in air or fluid. In terms of measurements, coil heaters and cable heaters vary according to coil inner diameter, outer diameter, length, and width. Some devices encase the coil or cable to protect it from damage and to maximize heat transfer. In other devices, the coil or cable includes an internal temperature detector such as a thermocouple.

Coil heaters and cable heaters are heating elements formed from straight, uncoiled segments of heating cable. Forming straight cables into patterns increases the surface area and heat transfer capability, but also requires increased energy and watt density. Most coil heaters and cable heaters operate on AC voltages. Some include a grounding wire or provide distributed wattage arrangements to concentrate heat distribution. Coil heaters and cable heaters can be configured with different termination options. For example, electrical connections can be made via a plug configuration and protected by a terminal box interface. Armor cable, metal braids, and flexible conduits are used to protect insulated leads.  

There are a variety of shapes and sizes for coil heaters and cable heaters. Some devices are straight, square, or rectangular. Others are round, coiled, spiral wound, or star wound. Spiral wound heaters are used to generate high temperatures in restricted areas. Star wound cables are offset coils inserted into pipes or ducts to create a turbulent flow in air or fluid. In terms of measurements, coil heaters and cable heaters vary according to coil inner diameter, outer diameter, length, and width. Some devices encase the coil or cable to protect it from damage and to maximize heat transfer. In other devices, the coil or cable includes an internal temperature detector such as a thermocouple.

Coil heaters and cable heaters are made from several different types of materials and typically include insulation. Sleeve, sheath, and jacket materials include aluminum, brass, copper, iron, nickel alloy, steel, and stainless steel. Insulation materials include ceramics, mica, minerals, and fiberglass. Mica is highly resistant to acids while fiberglass is impervious to many caustics. Some coil heaters and cable heaters may be fully or partially immersed in heated substances, while others are corrosion-resistant or suitable for cryogenic use. Clamping straps provide additional protection for coils and connections.

There are many applications for coil heaters and cable heaters. For example, larger devices are used in plastic injection molding machines, holding tanks, metallurgical analyzers, and pulp and paper processing. Coil heaters and cable heaters are also used in blow molding machines, oil reclamation equipment, and food and candy extruders. Smaller, localized devices are used in labeling, bag sealing, hot stamping, and packaging equipment.