The Welch 2522 is a vacuum and pressure pump all-in-one and are perfect for many common laboratory vacuum applications. The 2522 produces an ultimate vacuum pressure of 110 Torr (25.6 inches of Hg), maximum positive pressure up to 100 PSI, has a 22 liters per minute (0.76 CFM) pumping speed, and includes dial pressure gauges, regulators, and moisture traps on both the vacuum low pressure and positive pressure sides of the pump.

The Welch 2522 WOB-L is a laboratory duty dry oil-free diaphragm vacuum and pressure pump all-in-one. It produces vacuum on the suction side and pressurizes those evacuated gases to positive pressure one the other side. The Welch 2522 includes both vacuum and positive pressure side regulators, dial gauges, and moisture traps. The two regulators and two gauges make it easy to meet your vacuum and pressure requirements. The vacuum regulator and vacuum dial gauge are attached to the intake port. The vacuum regulator allows the vacuum level to be set between roughly atmospheric pressure and the maximum vacuum allowed for the pump model. A moisture trap keeps water from accidentally being drawn into the unit. The pressure regulator and pressure dial gauges are attached to the discharge port. The pressure regulator allows discharge pressure to be set between atmospheric and the maximum possible for the pump model. Discharge air is filtered and noise is muffled with a filter.

The Welch 2522 WOB-L pressure and vacuum pump come with intake and discharge hose barbs which accept 1/4” ID rubber pressure and vacuum hose. Hose clamps should be used to hold the hose in place. Since the vacuum side operates in the viscous flow regime, the small diameter of the hose will generate minimal conductance loss. For best results, we recommend the length of the tubing between the chamber and the pump be kept as small as possible.

The Welch 2522 WOB-L pressure and vacuum pump come with dial gauges mounted on the regulator assemblies. The vacuum gauge gives negative pressure - that is pressure below atmospheric. The reference point for the vacuum gauge is atmospheric pressure. The pressure gauge gives pressure above atmospheric. The reference point for the pressure gauge is atmospheric pressure. Please keep in mind that atmospheric pressure tends to vary from day to day. As a result of this variability, the dial vacuum gauge will indicate slightly different maximum vacuum readings from day to day.

The pumps will handle humid air and all wetted aluminum parts are treated for corrosion protection from moisture. All other wetted parts are stainless steel. A plastic trap with a ball check valve is attached to the regulator assembly to prevent water condensate from accidentally being ingested into the pump. If there is a chance liquid may be drawn from the process under evacuation, we recommend and additional liquid trap be placed between the process and the pump. A simple liquid trap is a filtering flask. When a heavy load of water vapor is evolved from the vacuum process, a cold trap is recommended to help prevent damage to the pump mechanism. A user's manual, brochure, and catalog sections in PDF format are available for downloaded below.