Screw Plug Immersion Heaters

Screw Plug Immersion Heaters

Screw plug immersion heaters are compact heating assemblies mounted through a threaded connection in a tank or vessel. The heater bundle is attached to a threaded plug, allowing installation and removal through a matching boss or coupling. They are commonly used where a bolted flange would be unnecessarily large or where a standard threaded port is already available. The design may be suited to water, oils, and compatible industrial liquids, with element material and watt density chosen for the medium and operating conditions. Correct thread specification, immersion length, clearances, and service access are essential. In viscous liquids or poorly circulated tanks, the design must be checked to avoid local overheating; in corrosive media, both the sheath and wetted mounting parts require careful material selection. Screw plug heaters can be offered with different thread standards, terminal enclosures, thermostats, and sensor provisions depending on the application.