Metal Sieve Vacuum Traps
Coaxial Vacuum Traps
Molecular Sieve Vacuum Traps
Liquid Nitrogen Vacuum Traps
Vacuum Traps (or, Foreline Vacuum Traps) on high vacuum and ultra-high vacuum systems are placed between the high vacuum pump and the backing pump. Vacuum traps are specifically designed to preclude various contaminants from entering the vacuum pump. Types of vacuum trap media include metal sieve, molecular sieve, metal or fiberglass fiber and liquid nitrogen.
Metal Sieve Traps
Metal Sieves are used with hydrocarbons to prevent any back stream when mechanical pump oil reaches vapor pressure. Sieve Traps are manufactured out of 304 stainless steel but can be swapped for copper upon request.
Molecular Sieve Traps
Molecular Sieve traps perform two functions simultaneously. The first function is the removal of hydrocarbons that may back stream toward the chamber when desired pressure is reached. Secondly, water vapor and other gasses can be removed from the atmosphere before reaching and contaminating the pump oil. To initialize or replace the sieve, heat needs to be injected into the system to remove all imperfections caught within the system by simple turning on the heater and allowed to run for 4 hours with the ballast valve open.
Particulate traps use a polyester felt filter to trap contaminants over 10 microns at a 98% efficiency. To clean and maintain the filter, simply clean with a vacuum cleaner regularly. These are not recommended to systems exceeding 150C. Should a polyester filter not meet your needs, please contact Apex to find a more fitting filter material.
Liquid Nitrogen pumps condensed gasses in a system before they can reach and contaminate the oil. Conversely, they also ensure fumes from the oil do not contaminate the vacuum chamber. Dual-tube traps allow for the attachment to a nitrogen source so as to never have to refill the trap.