BFM® with support rings

Many BFM® connectors can be manufactured with single or multiple support rings. These rings are available in either stainless steel or plastic, depending on the application. The rings themselves are affixed to the outside of the connector walls, so the product never comes in contact with the rings.

These rings keep the connector walls open when used in negative pressure applications, high pressure applications, or compression applications (bag loaders.)

  • Tapered connectors cannot be made with rings.
  • See Spec Sheet below for details on which connectors can have Rings.
BFM with SS or plastic rings
Physical Properties
Ring Material: SS (Stainless Steel T304L) or PE (Plastic)
Connector Material: Seeflex 040E
Corner Connector 040E
Seeflex 040AS
Teflex NP & NP Opaque
Teflex Woven
Blanking Sock
Seeflex 020 on Request.
Maximum Number of Rings (on a single connector) All permitted materials (except Teflex NP): 10, Teflex NP Ø150mm - 500mm: 8, Teflex NP Ø100 & 125mm: 6
Multiple rings evenly spaced at a minimum CL< 850mm (331/2”): 100mm (4”) apart (max 4) CL ≥ 850mm (331/2”): 200mm (6”) apart (max 10)

Our customer had a concern with keeping the walls on BFM® connectors from collapsing and creating a restriction in the vent line.

Our equipment operates under a vacuum of ~-1.0 to -0.5 InWC. We found that the BFM® connectors suck in at these pressures such that they create a restriction in the vent line which limits airflow and increases the pressure in our equipment to near 0 InWC. Apart from the compression/restriction, the connectors work very well. Do you have any recommendations for how I might be able to reinforce the middle of the connector such that it does not collapse in quite so much? Using a shorter connector is not an option as these connectors are already sized as aggressively as was recommended to be able to handle the vibration and still be able to reach both attaching points.

This customer was using BFM® Teflex NP connectors off a vibrating conveyor with operating temperature of  400 F to 450 F.  There are 4 discharges on this conveyor and they needed to maintain a slight vacuum on the system to prevent gas escaping the system. It worked fine with one connector. However, as they added more connectors, the collective restriction lowered the vacuum because each connector was pulled in.

BFM® manufactured its popular Teflex NP connector with 2 support rings and we sent it to the customer for testing. 

The customer was able to test it and it was wildly successful!

We were able to test the reinforced fitting today and it worked very well. We had our equipment under ~3” of vacuum and saw no restriction in the boot or in the flow going through it. Similarly, with the equipment bouncing, we did not see any significant vibration transfer to our ductwork. 

What would be the next step in getting more of these. Will we be able to retrofit our existing unused fittings?

Yes, the customer was able to get more as the Teflex NP with support rings is now a standardized item. BFM® Global, the manufacturer of BFM® fitting, continues to innovate, improve, and expand an already stellar product line to ensure every customer with their unique application has a solution that works for them.