The “L” Shaped Cast-In Heaters are typically used on square and rectangular twin screw extruder barrels in compounding and plastic
resin manufacturing applications. Due to high shear rates, which are common in this process, extreme operating temperatures and
high watt densities are frequently encountered. For these reasons MPI Morheat manufactures “L” shaped heaters in bronze or brass
alloys, which are capable of withstanding high temperatures at higher watt densities.
In the case of applications requiring lower temperatures and lower watt densities, aluminum alloys can be used. Aluminum castings
are desirable as they have greater thermal conductivity and weigh substantially less than their bronze or brass counterparts, allowing
for greater ease of installation.
For mounting purposes, the heaters can be designed with 45° flanged ear extensions that are bolted and drawn together, or can be
made with through holes machined into the casting body to bolt directly onto the barrel itself. Thermocouple and transducer holes or
other special features can be accommodated as well.
To enhance cooling capabilities, or to be used in place of integral feed screw cooling, “L” shaped heaters can be manufactured with
cast-in cooling tubes to satisfy liquid cooling requirements. This feature allows processors the ease of changing a single unit at a time,
thus representing a far less time-consuming and less expensive alternative should a cooling line become clogged or severely restricted.
– Cast-In Bronze or Brass Alloys for high temperature, high
– Flange bolt clamping arrangement or through holes in the
heater body, allowing bolt mounting directly to the barrel
– High precision machining of the inner contact surface of
the heater, yielding exceptional heat transfer to the process
– Choice of terminal protection housings
– Moisture resistant terminal housing which is available in
a variety of different styles and mounting arrangements
– Elevated temperature terminations and enclosures
– Prevents premature heater failure due to accelerated
corrosion or oxidation of terminals caused by high heater
To aid processors in reducing maintenance downtime, there
are several optional construction features to the basic “L”
shaped design that will extend the life and performance of
your Cast-In Heaters.
– Cast-In Aluminum Alloys for applications requiring lower
temperatures and less watt density
– 3/8” or 1/2” O.D. cooling tubes for liquid cooling
– Non-Exposed cooling tubes (Type RC). Eliminates cracked
and broken cooling tubes.