Adapter KF-40 to Welch Vacuum Pumps (Old Style), 1374, 1397, 8851, Thread Size 1-3/4-20, Stainless Steel
These adapters are KF-25 to Welch vacuum pumps, models, 1374, 1397, & 8851, Old Style Pumps. The flange size ISO-KF NW-40 to Welch pump thread size 1-3/4-20. They are commonly used to make connections between Welch vacuum pumps and ISO-KF Flanges. The ISO-KF flanges are often called quick flange fittings because they are quick to assemble. A circumferential clamp and centering ring form the vacuum seal between the connecting flanges (please see top right figure - click to enlarge). The centering ring contains a rubber elastomer o-ring. The standard sizes for quick flange fittings are KF-10, KF-16, KF-25, KF-40, and KF-50 with flange sizes NW-10, NW-16, NW-25, NW-40, and NW-50, respectively. They are made of corrosive resistant stainless steel.
Adapter KF-40 to Welch vacuum pump (Old Style), Models 1374, 1397, & 8851
ISO-KF Flange Size: NW-40
Thread Size: 1-3/4-20 NPSM
Common Dimensions: A = 2.50 in., B = 1.375 in.
FOR OLD STYLE WELCH VACUUM PUMPS, ie.
An Old Style Pump has an oil sight glass
held in place with a bolt ring, click on far right picture for example of an old style pump.
