Gear Clamp Failure and How to Avoid it
If you are a boat owner with an inboard power plant, you are familiar with the various hull penetrations for hoses for fueling, exhaust, and ventilation functions and hoses, connected with simple clamps, are attached to these penetrations you know that the watertight integrity relies on the unfailing performance of these simple thin-metal hose clamps, some costing just a few dollars. The prospect of taking on water is always a possibility, that disaster is easily avoided, as are the many less-dramatic results of their failures on fuel-fill and supply plumbing or sanitation and potable-water systems, to name a few. In short, quality hose clamps are vital to the operation of almost any vessel, and while they are a mundane bit of inexpensive hardware, mistakes in choosing and installing them can be very costly. To form an effective seal, hose clamps and the hoses they are applied to must be used with compatible, nipples and adapters, sometimes called hose barbs or bibs. The last thing you want is a failure because the hose was installed over a pipe fitting not specifically designed to support a clamped-in-place hose.
The oh so common worm-gear hose clamp which relies on a simple screw and threaded band effectively exerts uniform pressure on hoses and their fittings. As good as the original design may be, it can have issues. These clamps rely on a series of slots cut into the band to engage a worm screw / gear. Obviously, these slots reduce a significant portion of the band’s cross section, weakening it and allowing it to stretch when tensioned and this leads to microcracking, which in turn provides a toehold for corrosion, a form of metal decay peculiar to stainless steel alloys. When worm gear hose clamps part, they nearly always do so across one of these slots. This type of problem is most common with tubing and hoses less than 1 inch ID. For larger diameter hoses, like 2 and 3 inch, the easy way to insure against failure is to use 2 clamps side by side with the screws opposed. A good choice for ventilation and sanitary hoses is Tech Team’s #727 3 inch clamp https://techteamproducts.com/product/3-inch-hose-clamp-set-8-pieces/ https://www.amazon.com/dp/B07GZZ1KHV?ref=myi_title_dp , you might to watch the you tube video https://youtu.be/q5IiwTPVIdo or do a hey Siri or hey Alexa Google search for other ideas. Tech Team’s clamps have a stainless-steel band, screw housing, and screw to prevent corrosion related problems. In addition they have a thumb key tightener which is great for working in the typical tight spaces you find on a boat.
