Flanged Immersion Heaters


Flanged Immersion Heaters, both round flange and square flange models are a great choice for applications requiring larger wattages. Flanged immersion heaters are designed for installation into a pipe body, tank or pressure vessel using standard pipe size. These heaters are available in a wide selection of rates, sizes and sheath materials suitable for the heating requirements of water, air and other gases. Flanged immersion heaters are very efficient since all energy that is generated is dissipated directly into the medium which is being heated. All flanged heater models incorporate tubular heater construction welded or brazed into a carbon steel pipe flange. Nema 1 terminal enclosures are supplied with all standard units. Moisture resistant and explosion proof models are also available. A number of sheath materials like Titanium, Incoloy, Stainless Steel, Steel, and Copper can be used as required for specific applications.


Standard Flanged Immersion Heaters have a 150 lbs flanges but 300 lbs flanges are also available. To guarantee sheath material and watt density compatibility with material or process being heated consult NPH. All flanged immersion heaters we offer you including heaters for hazardous locations are CSA/NRTL and UL approved.

Flanged Heaters Guide | Flanged Immersion Heaters Flanged Immersion Heaters Specifications.pdf

Flanged Heaters Guide | Flanged Immersion Heaters How to Extend the Life of Your Immersion Heater-2.pdf

Flanged Heaters Guide | Flanged Immersion Heaters Flanged Immersion Heaters Wiring Diagrams.pdf

Flanged Heaters Guide | Flanged Immersion Heaters Flanged Immersion Heaters-Installation, Operation and Maintenance Instructions.pdf


Hot Water Storage Tanks

Warming Equipment

Heating & Preheating All Grades of Oil

Flanged Heaters Guide | Flanged Immersion Heaters Food Processing Equipment

Cleaning and Rinsing Tanks

Heat Transfer Systems

Process Air Equipment

Flanged Heaters Guide | Flanged Immersion Heaters Boiler Equipment

Freeze Protection of Fluids


Oil Heating Loops

Flanged Heaters Guide | Flanged Immersion Heaters Sewage Processing/Recycling/Water Purification

Caustic Solutions



Materials — Copper, steel, 304/316 stainless steel, Incoloy

Number of elements in flanges — 3, 6, 9, 12, 18, 21, 27, 36, 45 plus

Element diameter — 0.315” - 430"

Watt density — 6.5, 15, 23, 45, 75W/in2


Materials — Carbon steel, stainless steel,

Rating — 150 lb. pressure class per ANSI B16.5

Sizes — 3", 5", 6", 8" 10", 12", 14", 150 lb.

High conductivity elements —

Filled with highest purity blends of magnesium oxide refractory (MgO) compacted to rock hard density to insure maximum thermal conductivity and maximum electrical resistance, and assure long element life.

Heavy coil construction — Watt density on the heating coil is designed for low watt density operation by increasing the coil diameter and length to give maximum coil surface area and limit coil surface temperature, providing longer coil life.


Kilowatt ratings — 500 kW and above available


Materials — 316, 321, 347 stainless steel. Inconel, Incoloy

Ratings — 300 lb. up to 2500 lb., pressure classes available

Sizes — 10" , 12", 14", 16", and 18" available. Please contact NPH for

other materials or ratings.


Materials316, 321, 347 stainless steel. Inconel. Other materials available, please contact NPH

Other Features

ASME Sections I, IV, and VIII designed and certified. Baffles on elements to distribute flow. Passivation on stainless steel. Immersion lengths up to 240". Underwriters Laboratories U.L./CSA listing available. Consult NPH.


Safe operation of heaters equipped with these enclosures depends on employment of electrical wiring meeting National Electric Code and limiting maximum operating temperatures (including temperatures on outside of vessel, piping, flanges, screwplugs, enclosures and other heat conducting parts) as dictated by flammable liquids, vapors, or gases present. Approved pressure and/or temperature limiting controls must be used to assure safe operation in the event of system malfunction.

Terminal Enclosure Types

General purpose, sheet metal, (NEMA-1) painted with enamel. Moisture resistant, Nema 4X, Explosion Proof.

Grounding Connector Standard—

A solid terminal connector is standard on all NPH immersion heaters insuring positive ground and personal safety.


A thermostat protective well (thermowell) is standard on most models. This well is installed through the flange parallel with the heating elements. This 1/2" thermowell is provided for accepting a temperature sensing probe for use with a thermostat or other NPH type control system. Flexibility of the type of control can be provided to give exact process control precision to match your process needs. A contactor is needed when the line voltage and/or current exceeds the thermostat rating. Other types of controls are available where a high degree of accuracy or a more versatile control scheme is required. Electronic controls and complete control panels are easily installed. See the control Temperature Section for a complete selection.


NPH cannot warrant any electric immersion heater against failure by sheath corrosion if such failure is the result of operating conditions beyond the control of the heater manufacturer. It is the responsibility of the purchaser to make the ultimate choice of sheath material based on his knowledge of chemical composition of corrosive solution, character of materials entering the solution, and controls which he maintains on the process. * Not intended for use in hazardous locations.



Flanged Heaters Guide | Flanged Immersion Heaters Flanged Immersion Heaters Specifications.pdf

Flanged Heaters Guide | Flanged Immersion Heaters How to Extend the Life of Your Immersion Heater-2.pdf

Flanged Heaters Guide | Flanged Immersion Heaters Maximizing Heater Performance-1.pdf



Heat Calculation Examples:



Wattage Required to Heat Air flows:

Flanged Heaters Guide | Flanged Immersion Heatershttp://www.nphheaters.com/quote/industrial_process_heaters/wattage_required.pdf

Water Heating in an Insulated Tank:

Flanged Heaters Guide | Flanged Immersion Heatershttp://www.nphheaters.com/quote/industrial_process_heaters/wattage_insulated.pdf

Heating Oil in an Insulated tank:

Flanged Heaters Guide | Flanged Immersion Heatershttp://www.nphheaters.com/quote/industrial_process_heaters/wattage_heat.pdf

Wattage Required to Heat Flowing Oil:

Flanged Heaters Guide | Flanged Immersion Heatershttp://www.nphheaters.com/quote/industrial_process_heaters/wattage_oil.pdf

Common Industrial Heater Nema Enclosures Types:

Flanged Heaters Guide | Flanged Immersion Heatershttp://nphheaters.com/quote/industrial_process_heaters/technical_resource.htm

How To Order Flanged Immersion Heaters

Flange Size and Number of Elements
Pressure Class  
Flange Materials  
Sheath Material  
Enclosure Type  
"B" Dimension
Immersed length
Wattage (kw)
Voltage Phase
Thermostat Thermowell
High Limit Thermocouple Quantity



First Name Last Name
Company Name Position
Address City/State/Province
Zip/Postal Code Country
Phone Number Fax Number
Toll Free Number Email
Web Site OEM Distributor Process User
Quotation Request Required Delivery Date
have a salesperson contact me



UL Registered Firm World Wide Shipping CSA US
We Ship Our Industrial Process Heaters To OEM’s & Industry World Wide.

Inquiries & Technical Support

Telephone: 905-859-8225 Facsimile: 905-859-4691

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Toll Free: 1-877-674-9744