Controlling Static Build Up
Who really reads the owner's manual to their new product? Your Clemco owner's manual has information important to the efficient and safe use of our equipment. Doing you research and choosing the right media and equipment are the initial steps to achieve an efficient blast application operation.
The role of the blast equipment is to bring together elements that have materials flowing through hoses or pipes, while the resulting conditions of the activity result in static electricity. Dry air is necessary to an efficient blasting operation, it also adds to the buildup of static electricity. Blast media particles produce static electricity as they are propelled from the gun nozzle, when they move over the item being blasted, and when inside the recovery hose. Cyclone separators spinning media over large surfaces create static charges. If these charges accumulate and are not dissipated, they can cause a spark to occur. In a manual blast operation, if the charge is not eliminated, it will be released when the blast operator touches the blasting cabinet.
The cabinet must be wired to an earth ground in order to keep static electricity from building up. When all of the parts are connected, they all contain the same energy potential.
Properly grounding equipment is essential in light of the risks of static buildup. An electrical neutral or third wire can carry current in some areas, so connecting to a water pipe, electrical conduit or a metal frame building will not control static. Always remove any rust and paint from areas of contact to insure proper conductivity.
Low resistance static grounding cables must be used, at or less than 5 ohms of ground. Permanent ground installations should be checked yearly with an ohmmeter. Portable or temporary ground installations should be checked at startup and whenever the equipment is moved.
Avoiding a zap from your well-grounded cabinet is easy, just touch the blasted item to the metal grate or use a ground clamp to help dissipate any static being build up from the media ejection from the nozzle. Also, all rubber mats are nit the same. Rubber mats must be designed to withstand static charges and be connected to the earth ground. ZERO cabinets are all assembled with special hoses that rescue static thru its use of conducive material, and similar results can be achieved by using wire spiral exhaust hoses. The wire works to keep the hose from falling in on itself, and also dissipated electricity when grounded on either end. Shoes can also convey static electricity and should be inspected by the wearer to ascertain they will not supply a charge.
Grounding is the main way to reduce injury and loss of efficiency. Using these methods, the blast cabinet can be a safe operating space.