At last, the end of the “Great Gasket” saga. This last installment is devoted to a less well known type of gasket material and how it is used.
Ever wonder about the square gasket dangling off of the end plates or access hatches of your boiler? Most of the time, we just kind of tuck the dangling ends in, bolt down the plate or hatch and don’t care one whit about what’s going on. What’s going on is hot toxic gasses are leaking through the area of the faulty gasket to the outside of the boiler. In addition to not being good for living things to breathe these noxious fumes, air flow within the boiler itself may be disrupted from the proper pattern, decreasing burner efficiency and increasing fuel consumption.
Since the use of asbestos has been discontinued, the material of choice for this use is a woven fiberglass which comes in an assortment of shapes, sizes and weaves. For our purposes it is called SQUARE BRAIDED FIBERGLASS ROPE (for Google search). I use high temperature silicone adhesive to hold the braid in place. Start by thoroughly wire brushing (ALWAYS WEAR EYE PROTECTION AND LEATHER GLOVES WHEN USING WIRE BRUSHES OF ANY TYPE) the area where the old gasket was attached to the plate or hatch. Measure the required length by wrapping the braided rope around the circumference of the gasket portion of the end plate or access hatch cover with an overlap of roughly 2″. Take a sharp knife and miter the ends where they meet with about 1 inch of overlap. Now smear the silicone adhesive around the circumference of the area on the plate or hatch which will be covered by the braided rope and allow time for the adhesive to get tacky. Then drop the braided rope onto the plate or hatch and position it into place; allow time for the adhesive to set (is strong enough to support the braided rope). When the adhesive just sets, lay a bead around the outside of the braided rope and allow the whole assembly time for the adhesive to cure (harden or become non tacky). When the adhesive has fully cured, carefully position then bolt the cover or hatch into place.
I smear a thin layer of Teflon paste over the sealing face of the braided rope. This will prevent any uncured adhesive from adhering between the braided rope gasket and the surface it is seating; preventing possible tearing of the gasket during future removal of the plate or hatch.
Well that’s it for this month. Got a suggestion for the next issue? Don’t be shy, surely there’s some maintenance procedure you’d like to know about. Send a request or suggestion to bruce@eztimers.com or call me at (702) 376-6693.
