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For enclosures and equipment that rely on flexible seals, in- flatable bladder-type seals might be a better choice than compression seals. They are more forgiving of irregular or misaligned mating surfaces, which cuts manufacturing costs and boosts sealing in- tegrity. Theyre also easier to use by requiring less force, so technicians donҒt have to force two components together for a good seal. Instead, they just move the mating parts freely into place and inflate the seal. The only downside is that the inflatable part of the seal, the bladder, needs compressed air to operate. But in many set-...

heavy-duty channelseal handles higher pressuresbut doesnt have much travel. It features a top surface and base that are reinforced to hold their shapes. But its side- walls are not reinforced, let- ting them stretch when the channel seal handlesheavy-duty applications and mounts in a groove or metal channel that supports its sides and helps keep it in place. It may be held in place by adhe- sives or simply by friction with the sidewalls. These seals are widely used as grippers on ro- bots and in part fixtures and handling.The heavy-duty snap seal handles higher pressures and is more durable than...

One-piece screw pins and clipscommonly hold footed seals in place. Adhesives and mechanical interference fits can also be used. One-piece retainerScrew pinClips seal is inflated to deliver thenecessary travel.For extra heavy or unevenloads and rough mating sur- faces, sealing pads are often placed atop any of the seals mounted in grooves or chan- nels. > Most seals need only one airconnection and it can be built into the base or the end, de- pending on requirements. More connections may be needed for faster cycling, to hold large seals in place, or when inflating seals with a fluid. > Cutting...

Air supply: Engineers often dismiss inflat-able seals because of the air-supply issue. This neednt be a problem. In most industrial or bulk transport settings, compressed air is usually available. And there are often simple solutions for nonindustrial applications re- quiring infrequent seal cycling. On yachts, for example, the same foot pump or compressor that inflates rafts can easily activate the seals. For flood doors, which may be deployed only once or twice a season, built-in compressed air tanks fill the bill. The dip: Certain spots on inflatable sealsmay not rise to the full height of...