Description
Welco R50 Vacuum Regulator Valve with Gauge 0-8 in Hg 0-200 mm Hg Melchior
The Welco R50 is a full-line vacuum regulator valve with an integrated dial vacuum gauge, manufactured by Melchior, Armstrong, Dessau Co. Inc. of Ridgefield, NJ. The regulator controls vacuum level through a rotary ON/OFF mechanism with clearly labeled Increase and Decrease directions on the top dial face. The attached gauge (US Gauge 23055-1) reads vacuum in dual scales simultaneously.
Specifications & What's Included
- Manufacturer: Melchior, Armstrong, Dessau Co. Inc. (Ridgefield, NJ, USA)
- Model: Welco R50
- Type: Full-Line Vacuum Regulator Valve with Integrated Gauge
- Gauge range: 0–8 in Hg (inches of mercury)
- Gauge range: 0–200 mm Hg (millimeters of mercury)
- Gauge designation: Full Line Vacuum
- Gauge model: US Gauge 23055-1
- Gauge face: White dial, dual-scale, Welco branded, Made in USA
- Body finish: Chrome-plated
- Control: Rotary valve, ON (Increase) / OFF (Decrease) vacuum
- Outlet port: Compression-style fitting on side port (visible in photos)
- Inlet connection: Threaded bottom port
- Includes: Valve body with attached gauge — no hoses or additional fittings
Applications
Vacuum regulators like the Welco R50 are used to set and maintain a precise vacuum level drawn from a central vacuum supply or vacuum pump, delivering a controlled reduced vacuum to a process or instrument. They are standard accessories in laboratory vacuum systems, vacuum chamber setups, filtration rigs, desiccator manifolds, and light industrial vacuum lines. The dual in Hg / mm Hg scale is particularly useful in scientific and laboratory environments where vacuum levels are specified in either unit. Welco regulators of this type were widely used in mid-20th-century American industrial and lab settings; the Melchior, Armstrong, Dessau Co. was a well-regarded U.S. manufacturer of gas and vacuum control equipment. Units like this remain serviceable for low-demand laboratory and vacuum chamber applications wherever a chrome-body regulator with an integrated gauge is needed.
This Welco R50 Vacuum Regulator Valve with Gauge has been inspected and appears to be in good used condition. The chrome body shows light surface wear and minor patina consistent with age and prior use. The gauge face is clean and legible — both scales (0–8 in Hg and 0–200 mm Hg) are clearly visible. The unit was pulled from a working environment where it was previously in service. Please review all photos and contact us with any questions before purchasing.
Warranty Information
Additional Information
Brand: |
Welco |
Manufacturer: |
Melchior, Armstrong, Dessau Co. Inc. |
Model: |
R50 |
MPN: |
R50 |
Type: |
Vacuum Regulator Valve with Gauge |
Gauge Model: |
US Gauge 23055-1 |
Gauge Range (in Hg): |
0–8 in Hg |
Gauge Range (mm Hg): |
0–200 mm Hg |
Vacuum Range: |
Full Line Vacuum |
Gauge Type: |
Full Line Vacuum Dial Gauge |
Control Direction: |
Increase / Decrease (ON/OFF rotation) |
Body Finish: |
Chrome-plated |
Country/Region of Manufacture: |
United States |
Manufacturer Location: |
Ridgefield, NJ, USA |
SKU: |
40999 |
Seller Notes: |
Includes attached vacuum gauge (US Gauge 23055-1). Valve body only — no hoses or fittings. |
Condition Notes: |
This Welco R50 Vacuum Regulator Valve with Gauge is in good used condition. Chrome body shows light wear and minor patina. Gauge face is clean and legible. Pulled from a working environment. Contact us with questions. |
California Prop 65 Warning: |
WARNING: This product can expose you to chemicals including lead and lead compounds, and DEHP (a phthalate), which are known to the State of California to cause cancer and birth defects or other reproductive harm. Go to P65Warnings.ca.gov |