Sealed Mica Nozzle Heaters are hermetically sealed for liquid plastic during the manufacturing process. The connection between the heating element and the leads is protected by a special fitting made of 1 mm thick brass or stainless steel, without welding which allows a high mechanical strength in the most delicate area of the heater.
During manufacturing, the Sealed Mica Nozzle Heaters are submitted to extremely high pressure that ensures high insulation, excellent thermal exchange, lack of internal voids, perfectly smooth contact area for an optimum and uniform heat transfer to every part of the nozzle.
The Sealed Mica Nozzle Heaters are available in either Brass or Stainless Steel versions, depending on the application. It is recommended to use stainless steel nozzles where the molding or extrusion of PVC is involved as stainless steel will withstand the corrosive fumes far better.
The Sealed Mica Nozzle Heaters are a rugged product that resists very well to wearing and shocks. The inner profile is perfectly round, providing a perfect coupling with the nozzle. Size of the connecting cap is minimal, giving extremely limited overall dimensions. Power connection is performed by a Standard metal braided cable with Length of 1000 mm.
CONSTRUCTION
A thin layer of the "high" thermal conductive MI material is used to electrically insulate the element wire from the inside diameter of the heater sheath. A thicker, "low" thermal conductivity layer backs up the element wire, directing the heat inward toward the heated part. The result is more efficient heat transfer—a performance solution lowering element wire temperatures and increasing heater life.
MOUNTING
Good thermal contact between the element and metal surface to be heated is essential. It is therefore important that elements are clamped on tightly and that clamps are tightened again when the element has reached operating temperature. Correct fitment and tightening up of these heaters is critical to ensure not only excellent heat transfer but also longevity.
STORAGE & COMMISSIONING
Elements are susceptible to moisture and should be stored or used in a dry environment. It is recommended to heat up the elements gently after a prolonged period out of commission. This allows moisture to escape and prevents damage to the elements. Some temperature controllers have a “soft-start” feature, but a similar result is achieved by turning the temperature controller down initially.