BFSG – Integral Sight Glass / Floating Ball Check Valve

The BFSG combines a tubular sight glass with a floating ball check valve, constructed from a heavy duty borosilicate glass with its superior corrosion and thermal performance. The glass is tube held securely between two PFA lined carbon steel flanges. Inside the BFSG are two PTFE seats (the lower one castellated and the upper one with a Chemraz® o-ring seal)  with a hollow PTFE floating ball trapped between them. These sight glass / non-return valves are used to safeguard vacuum pumps from failure caused through liquid being drawn into them. Under normal operation the gasses pass up past the ball and through the sight glass into the vacuum pump. If something goes wrong with the process and liquid enters into the vacuum line the sight glass fills with this and the ball floats up to the seat preventing the liquid from passing and damaging the pump. Not only is the pump protected but the sight glass gives clear visual indication of the presence of liquid in the line.

To Suit ASME 150 and Din PN10/16 Flanged Piping Systems

Dimensions
To Suit Pipework Face – Face Flange ø Raised Face ø Weight Glass
ASME 150 Piping System
Inches mm Dim. A mm Dim. B mm Dim. C mm Kg ømm Wall mm
1 25 152 110 51 3.8 30 4.5
1 1/2 40 178 125 73 5.2 50 7.0
2 50 203 150 92 7.7 60 9.0
3 80 241 190 127 13.5 90 9.0
4 100 292 230 157 18.8 120 9.0
DIN PN 10/16 Piping System
Inches mm Dim. A mm Dim. B mm Dim. C mm Kg ømm Wall mm
1 25 160 115 68 4.0 30 4.5
1 1/2 40 200 150 88 5.6 50 7.0
2 50 230 165 102 8.5 60 9.0
3 80 310 200 138 12.3 90 9.0
4 100 350 220 162 18.8 120 9.0

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

 

image of floating ball check valve