Silo Bands and Bin Activator Sleeves, Built to Your Flanges

What a silo band has to do

A bin activator hangs off the bottom of the silo cone on isolation mounts and vibrates to keep material flowing. The band is the only thing connecting the two, so it has to seal against a fine powder while letting the activator move freely. If the band is too stiff, it fights the vibration and the activator stops working the way it was designed to. If the seam is glued rather than cured, the constant flexing walks it apart and you get a dust leak at head height on a silo.

That is the case for hot vulcanizing here specifically. A silo band flexes thousands of times an hour, every hour the plant runs. It is the single worst place on a bulk plant to put an adhesive seam.

Measuring one

Three numbers, and the first two are usually different.

• Large end inside diameter. Measure across the inside of the silo cone flange.
• Small end inside diameter. Measure across the inside of the activator flange. On many installations this is smaller, which makes the band tapered.
• Length. The vertical gap between the two flanges, plus overlap on each end for the clamp bands. Leave the band with slack rather than stretched. It has to move.

If the activator hangs offset rather than centered under the cone, note it and send a sketch with the offset dimension. We build offset transitions, they just take a different pattern.

When the two ends match, use the straight setting in the builder. When they do not, switch it to Tapered and give us both. See the tapered rubber boots page for more on how cones get built.

Material and wall

Cement, fly ash, flour, sugar, plastic pellets and most powders run fine on a 1/4 inch pure gum wall. Go to 3/8 inch where the silo carries something abrasive or the band is large enough that a thin wall would sag under its own weight. Above roughly 180 degrees Fahrenheit continuous, ask us about EPDM instead of gum rubber and note the temperature in the RFQ.

Band clamps can be quoted with the sleeve. Say so in the notes and we will size them, which on a tapered band means two different clamps. It saves you a second purchase order.

More on this equipment on the cement silos and terminals page, or see every size we cut.