ABOUT
Screw Plug Heater
Screw Plug Heaters are smaller versions of Immersion Heaters in which the heater flange is replaced with a Threaded Plug. A Single or multiple tubular heating elements that fit into a thread hexagonal head are then screwed directly through a threaded coupling in the tank wall or vessel or installed process line. Screw plug heaters are an easy way to heat up solutions in smaller containers that may or may not require auto control on temperature. The Heaters can be installed either horizontally or vertically in the tank. The heater is compatible with both Single-phase as well as three-phase power supplies.
About Screw Plug Heater
The screw plug heaters are also be provided with a Thermowell, in which a temperature sensor can be installed for the Temperature monitoring and control purpose. In most of the applications, a simple thermostat will be installed inside the thermowell and pre-wired with the installed heater to ensure the heater is ON / OFF at a pre-set temperature. The Thermostat knob can be projected outside the terminal cover for easy access of the operator.
Key Features
- Efficient Heating and operation
- Easy to install
- Maintenance-friendly
- No expensive
- Environmental performance
| Sheath Material | SS, Alloy 600 series, Alloy 800 series, Hastelloy, Titanium, copper, etc |
| Power Rating | 0.1kW to 50kW |
| Screw Plug Material | CI, Carbon steel, Brass, SS, etc |
| Screw Plug NPT fittings | 1”, 1.1/4”, 1.1/2”,2”,2.1/2”, 3” (BSP/ NPT) or equivalent Metric threads |
| Voltage | 120 to 690V AC Single phase or three-phase |
| Terminal Enclosure | Safe/Hazardous |
| Control | Thermocouple, RTD, Thermostat, Digitally controlled |
Construction
1. Nickel Chromium Resistance wire for high mechanical and creep strength for maximum heater life. Nickel-Chromium resistance coil is fusion welded to the metallic terminal pins.
2. High Purity magnesium oxide fill selected for maximum dielectric strength and thermal conductivity, highly compacted for maximum heat transfer.
3. Stainless steel sheath / Inconel sheath for oxidation and corrosion resistance in a wide variety of environments and are suitable for high temperatures applications
Sheath Selection Guide
The different sheath materials used in these heaters have different watt densities and operating temperatures. While choosing the sheath material following points should be looked at
- Stainless Steel: Maximum operating temperature is 1200 °F while the maximum watt density is 120 W/in2
- Steel: Maximum operating temperature is 750 °F while the maximum watt density is 120 W/in2
- INCOLOY: Maximum operating temperature is 1600 °F while the maximum watt density is 120 W/in2
| Application | Sheath material | Screw plug material |
| Clean water, Freeze protection, hot water storage, Boiler, and water heaters, cooling towers, Solutions not corrosive to copper | Copper | steel |
| Hot water, steam boilers, mildly corrosive solutions (in rinse tanks, spray washers) | Incoloy | steel |
| Oils, Gases, Mildly corrosive liquids, stagnant or heavy oils, high temperature, low flow gas heating | Steel
| Steel |
| Process water, soap, and detergent solutions, Soluble cutting oils, demineralized or deionized water | Stainless steel | Stainless steel |
| Mildly corrosive solutions | Stainless steel | Stainless steel |
| Severe corrosive solutions, demineralized water | Incoloy | Stainless steel |
| Light Oil, Medium Oil | Steel | Steel |
| Food Equipment, Food Equipment with cut out | Incoloy | Stainless steel |
Applications
- Clean water, hot water storage, portable water, freeze protection of liquid
- Hot water, steam boilers, mildly corrosive solutions (in rinse tanks, spray washers), vapor degreasers
- Severe corrosive solutions, demineralized water, food equipment
