ChemTec LPH Flow Switch & Closed-Loop Cooling Systems

Metal casting and plastic molding are near‐net shape manufacturing processes. Liquid material fills a die, solidifies and is ejected. A few quick finishing operations later and a precision part is ready for shipping or assembly. The key to making money though is doing this quickly. Molding and casting machines are expensive, as are the dies, so throughput and utilization must be maximized. That means chilling the filled die as fast as possible, and that takes sophisticated cooling systems.

ChemTec LPH

Cooling system on an injection molding machine.

Cooling Options

Most cooling is achieved by running cold water through the hot production tooling. As heat from the production tooling is transferred into the water, the metal or plastic begins to solidify. The faster this transfer occurs, the faster and more efficient is the production process. In the past manufacturers, might have run the warm water straight into a drain but today that’s recognized as wasteful and possibly harmful to our environment. Three superior alternatives to these types of closed-loop systems are cooling towers, water chillers and adiabatic cooling, but these methods may not always be available or cost effective.

ChemTec LPH

ChemTec LPH Flow Switch in acrylic.

ChemTec LPH Series
  • Compact size
  • Most economical
  • Close on/off differential
  • Materials: Acrylic, Brass, 316ss or Teflon

The LPH senses abnormal flow conditions with a magnetic piston suspended in the fluid stream. If the flow moves outside of set limits the magnetic field changes by a small but detectable amount. When this happens an alarm can be set or other actions taken as appropriate, such as shutting down fan motors.

For more information, call Ryan Herco Customer Service at 1.800-848-1141.


  • ChemTec LPH Series Flow Switch Data Sheet