Welch DuoSeal 1400N Vacuum Pump

Welch Belt-drive vacuum pumps are known world-wide to be reliable and durable in the most demanding applications. The belt drive feature runs the pump at a lower rpm which reduces frictional wear and sound. The reduced friction also keep the oil cool which increases overall vacuum depth. The large oil reservoir dilute contaminates and keeps the internal parts well lubricated. These pumps are constructed of iron and steel (not aluminum), so they last longer than direct drive pumps, but are heavy. 

Belt-drive vacuum pump are available in three types: DUOSEAL, CHEMSTAR and CAPTURE.

1. DUOSEAL vacuum pumps are used in most common lab and industrial applications. DUOSEAL pumps are available in 6 models of two-stage vacuum pumps and 2 models of one-stage pumps.
2. CHEMSTAR pumps are designed to tolerate harsh chemical contamination with vital parts corrosion resistant and uses Welch Gold oil, a synthetic pump oil designed to resist chemical attack.
3. CAPTURE pump is used for refrigerant recovery and transfer.

Chemstar pumps have PTFE coated oil cases and Fluorelastomer gaskets and seals and are especially suited for corrosive gases. Where corrosive vapors or large quantities of condensable vapors are evolved from vacuum processing, a cold trap must be used in the connecting line to the pump. It will help prevent damage to the pump mechanism and reduce oil contamination. The cold trap, immersed in liquid nitrogen or dry ice and acetone. The refrigerant to be used depends upon the freezing point of the contaminants. A variety of cold traps are available from Goldleaf Scientific here

Manual