Molecular Sieve (Foreline Trap)

These foreline traps perform as protectors for both vacuum pump and chamber. The zeolite desiccant removes hydrocarbons which backstream toward the chamber when the mechanical pump oil is at it's vapor pressure. Also, the zeolite traps water vapor and other gasses before they reach the mechanical pump and contaminate the pump oil.

Depending on the process, this can reduce the oil change frequency significantly. For maximum conductance the sieve material is contained in a suspended basket fabricated from perforated 304 stainless steel. This design provides conductance to the sieve at the top of the basket as well as around the periphery. A mid-basket baffle causes the gas to enter one-half of the basket and to exit the other half.

When initializing a trap, replacing the sieve or when base pressure cannot be achieved, the sieve should be regenerated by turning on the heater (110VAC) for 4-8 hours with the mechanical pump running with it's ballast valve open. The frequency and duration of sieve regeneration is dependent upon the kind and amount of gasses produced by the particular application.
Sieve materials may be replaced through the top port of the trap. Dump the used sieve material, replace with new, reattach the basket/end plate then perform the regeneration process outlined above.

A molecular sieve charge and regeneration heater are included with every trap. A standard trap comes with a 4" trap body, vacuum ports flange are available in NW16/ NW25/ NW40/ CF16/ CF35.

A bigger trap is also available upon request.