Tubular sightglass with floating hollow PTFE ball to prevent liquid entering vacuum pumps
Tubular sightglass with floating hollow PTFE ball to prevent liquid entering vacuum pumps

Combined Tubular/Floating Ball Check Valve

Combining a tubular sight glass with a floating ball check valve, the BFSG is made from a heavy duty borosilicate glass, with a superior corrosion and thermal performance. The glass is securely tube held between two PFA lined carbon steel flanges, while inside there are two PTFE seats – the lower one castellated and the upper one with a Chemraz® o-ring seal, and a hollow PTFE floating ball between them. The sight glass/non-return valves are used to safeguard vacuum pumps from liquid being drawn into them, which can cause them to fail.

When operating normally, the gasses will travel up past the ball and pass through the sight glass into the vacuum pump. If an issue with the process causes liquid to enter into the vacuum line, the sight glass with fill this, and the ball will float up to the seat. This prevents the water from passing into and damaging the pump. This ensures the pump is protected, while also providing a clear visual indication of the presence of liquid in the line.

To Suit ASME 150 

Dimensions
To Suit Pipework Face – Face Flange ø Raised Face ø Weight Glass
Inches Dim. A In. Dim. B In. Dim. C in. Lbs ø In. Wall In.
1 6.0 4.33 2.01 8.3 1.18 0.18
1 1/2 7.0 4.92 2.87 11.4 1.97 0.28
2 8.0 5.91 3.62 16.9 2.36 0.35
3 9.5 7.48 5.0 29.7 3.54 0.35
4 11.5 9.06 6.18 41.3 4.72 0.35

The BFSG tie rods can be adjusted without removing from the pipeline, all wetted parts are PTFE, PFA and Borosilicate Glass.