Screw Plug Heater

Screw Plug Heaters represent advanced compact immersion heating technology featuring precision-engineered hairpin tubular heating elements permanently welded or brazed into NPT/BSP threaded hex plugs for direct installation in tanks, vessels, and process systems. These sophisticated heating solutions are specifically designed for efficient direct immersion heating of oils, water, chemicals, and diverse process fluids where space constraints and installation simplicity are critical requirements.

High watt density up to 100 W/in² for intensive heating
Universal NPT/BSP thread installation (½″ to 4″)
Replaceable elements without tank drainage

Technical Specifications

Heating Element Materials	High-grade NiCr and FeCrAl alloy tubular coils
Sheath Construction	SS304/316/316L, Incoloy 800/825, Inconel, Copper
Plug Materials	Carbon Steel, SS304/316, Brass, Incoloy (zinc plated)
Thread Configurations	NPT and BSP threads from ½″ to 4″
Power Range	0.5 kW to 25 kW (single and three-phase)
Voltage Options	110V, 230V, 415V, 480V (single and three-phase)
Watt Density	Up to 100 W/in² (application optimized)
Maximum Operating Temperature	400°C (750°F) continuous operation
Element Length Range	50mm to 3000mm immersion depth
Insulation Type	Compacted high-purity MgO powder
Terminal Rating	IP65/IP67 weatherproof and explosion-proof options
Control Integration	Built-in thermostat, over-temp sensing, dual-element switching
Gasket Materials	PTFE, Graphite, Viton (application specific)
Certifications Available	ATEX, PESO, IECEx, UL (hazardous area approved)

Construction

Precision Hairpin Heating Element: High-performance NiCr or FeCrAl tubular coils with compacted MgO insulation in precision-drawn stainless steel or Inconel sheaths for efficient heat transfer and superior electrical isolation.
Engineered Threaded Plug Assembly: Precision-machined carbon steel, SS304/316, brass, or Incoloy hex plug with NPT/BSP threads providing leak-tight mounting and superior mechanical strength.
Professional Terminal Enclosure: IP65/67-rated weatherproof housing with high-temperature ceramic terminal block, cable gland, and optional integrated control systems for secure wiring and environmental protection.
Advanced Sealing System: High-performance PTFE, graphite, or Viton gaskets engineered for chemical resistance, temperature cycling, and leak prevention in demanding process applications.
Precision Element Mounting Collar: Engineered locknut and support assembly ensuring stable vertical or angled immersion positioning without element movement or mechanical stress.

Key Features

Direct immersion heating for maximum thermal efficiency
Replaceable heating elements without complete tank drainage
Comprehensive alloy selection for diverse chemical compatibility
Optional explosion-proof and flameproof certifications available
Rapid thermal response with uniform heat distribution
Compact design optimizing installation space requirements
Low maintenance requirements with extended operational life
Integrated temperature control and safety protection systems
Universal NPT/BSP threading for worldwide compatibility
Custom power ratings and voltage configurations available

Applications

Industrial water and oil heating tanks
Chemical process vessels and reactors
Steam generation and boiler systems
Lubrication oil conditioning systems
Food and beverage processing equipment
Pharmaceutical manufacturing vessels
Grease and solvent heating applications
Hydraulic fluid and oil reservoir heating
Power plant auxiliary heating systems
HVAC and building services equipment