Screw Plug Immersion Heaters
Industrial immersion heaters are medium capacity heating units designed to heat liquids, viscous fluids, forced air and gases inside tanks, vessels and pipes. Bucan screw plug electrical immersion heaters are designed to be immersed directly into the gas or liquid being heated; since these heaters come into direct contact with the gas or liquid, heat-up times are very fast.
Immersion heaters manufactured at Bucan consist of a single or a set of tubular elements that are formed into hairpins and welded or brazed to a screw plug. The sheath material of the heating elements could be steel, copper, stainless steel or Incoloy.
The standard screw plug sizes utilized are 1”, 1 1/4, 2” and 2 1/2” and are made of steel, brass or stainless steel, depending on the application. Various types of electrical protective enclosures, built-in thermostats, thermocouples and high-limit switches can be incorporated into screw plug immersion heaters.
Immersion heaters may be used to to heat up flammable liquids or gases in industrial applications. Contact us to inquire about our explosion proof housing units.
|Screw Plug NPT size||Plug material||Standard element diameters||Maximum voltage||Phase||Heating elements material||Maximum number of elements|
|0.315"||300 V||1||COPPER STEEL
|1 1/4"||0.315"||300 V||1||2|
|2"||0.430"||600 V||1 or 3||3|
|2 1/2"||0.430"||600 V||1 or 3||
PROCESS WATER HEATING
HEATING OILS, WAX, TAR, ASPHALT, PARAFFIN
MILD ALKALINE & ACID SOLUTIONS
MAXIMUM TEMPERATURE AND SHEATH MATERIAL SELECTION TABLE
|Heater sheath||Maximum sheath temperature||Used to heat|
|Steel||7500F (4000C)||oil, hydraulic oil|
|Copper||3600F (1800C)||water, tap/municipal only|
|Incoloy 800®||15000F (8150C)||water, alkaline solutions, air, gases, radiant|
|Incoloy 840®||14000F (7600C)||air, radiant|
|Inconel 600®||16000F (8700C)||strong alkaline solutions, high temperature gases|
|Stainless steel||12000F (6500C)||de-ionized, de-mineralized, process water, some mild acids|
NEMA 4 (MOISTURE PROOF) TERMINAL BOX
BUILT-IN SINGLE OR DOUBLE POLE THERMOSTATS
PASSIVATION FOR STAINLESS STEEL AND INCOLOY HEATERS
BUILT-IN PROCESS OR HIGH LIMIT THERMOCOUPLES
SPECIAL PLUGS OR NON-STANDARD THREAD SIZES
NEMA 7 (EXPLOSION PROOF) TERMINAL BOX, PLEASE CONSULT THE FACTORY
Immersion heaters use the bulb and capillary style thermostats. These thermostats operate by the principle of expansion and contraction of a heat sensitive liquid found inside the bulb and capillary assembly, which controls the activation of an electrical switch inside the thermostat.
Thermostats in most cases open the electrical circuit when the desired temperature is attained (open on rise). The standard thermostat utilized is 25A Max, up to 240V, single-pole single-throw style with a temperature range of 10-120°C. The table below shows other ranges of thermostats that are available.
|Thermostat||Contact Operation||Temperature Range||Maximum Amps||Maximum Voltage|
|T||SPST||10 to 120 C||25A||277V|
|T1||SPST||-18 to 40C||25A||277V|
|T2||SPST||70 to 280C||25A||277V|
|T3||SPST||160 to 370 C||25A||277V|
|T4||DPST||10 to 120 C||15A||600V|
|T5||DPST||-18 to 40C||15A||600V|
|T6||DPST||70 to 280C||15A||600V|
|T7||DPST||160 to 370 C||15A||600V|
Terminal Boxes for Screw Plug Immersion Heaters
|Terminal Box Type||Fig.#||Dimension "A"||Dimension "B"||Dimension "C"||Hole Size "E"|
|NEMA 1 Terminal box||fig. 1||3 3/4" Dia.||2 3/4"||N/A||7/8" knock-out|
NEMA 1 Terminal box
with built-in thermostat
|fig. 2||3 3/4" Dia.||3 3/4"||N/A||7/8" knock-out|
|NEMA 4 Terminal box||fig. 3||3 1/2" Dia.||3 1/8"||4 1/2"||1" NPT|
NEMA 4 Terminal box
with built-in thermostat
|fig. 4||4 1/4" Dia.||5 3/16"||5 1/4"||1" 1/4" NPT|