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BFM fittings Seeflex 040E vs. 020E; What’s the Difference?

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BFM fittings Seeflex 040E vs. 020E; What’s the Difference?

Our most popular BFM fitting, the Seeflex 040E, is definitely considered the standard flexible connector. Although there are over 16 different types of sleeve connectors available, the Seeflex 040E is the most versatile material. Another well-known option, the Seelfex 020E, has many similar properties, but when do you use one over the other? What’s their ideal installation locations?

Similar Yet Different BFM fittings

On the surface, these two materials are very similar. They both possess the standard gloss finish, have the same surface resistance at 10 10 ohms and have an air permeability of 0. Both work exceptionally well a control dust, possess superior chemical resistance for CIP & washing, and have no memory, therefore will not fracture with constant flexing.

That’s where most of the similarities end.

The 040E in Seelfex 040E designates its thickness, 0.09mm wall thickness, or 1/32 inch. The 020E is 0.35mm wall thickness, or 1/64 inch. An ideal situation to use the 020E, the thinner thickness of the two, is a lightweight media specifically designed for load cells and weigh scale type equipment. Also, the 020E is more flexible, so it’s an ideal solution in moving applications where flexibility is required. The standard Seelfex 040E is a sleeve that works very well in many situations, especially static installations.

Comparing Seeflex 040E vs. Seeflex 020E

As you’ll see in the chart below, they vary greatly in their tensile strength, operating temperatures, and tear strength. All of these should be taken into consideration, along with their installation location, when selecting which material is appropriate for your installation.


Seeflex 040E Seeflex 020E
Wall Thickness 0.9 mm/ 1/32″ 0.35 mm/ 1/64″
Tensile Strength (Mpa) 40 78
Operating Temp Range -13 to 230 deg. F -13 to 176 def. F
Max Surge Temp 248 deg. F 212 deg. F
Ultimate Elongation (%) 593 644
Tear Strength – Die C (N) 67 17

One thing to consider with the Seeflex 020E sleeve is the pressure rating. Since the sleeve itself is thinner to provide more flexibility and less weight, it may degrade quicker over time.

Many variables should be considered when selecting either a Seeflex 040E or Seelfex 020E sleeve. Please fill out the form below to get any questions answered any and for assistance in the selection of the perfect BFM fitting fit.


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