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1945 Theatre Catalog, 4th Edition, Page 404 (380)

1945 Theatre Catalog, 4th Edition
1945 Theatre Catalog
1945 Theatre Catalog, 4th Edition, Page 404
Page 404

1945 Theatre Catalog, 4th Edition, Page 404

wasteful. Use the type of lubricant recommended by the manufacturer. Instructions provided at the time the equipment was installed also include the information on proper lubrication. Keep bearings clean. Use extra care when greasing ball bearings, to prevent dust or foreign particles from entering. When bearings show unusual wear, or seem in any way to be faulty, call in an expert service engineer.

Belts and Pulleys

Units which have motor-drive fans, compressors, or pumps will also have a belweitheli of the flat- or V-belt type of drichunless the equipment is mounted on the motor shaft or is direct-connected by a coupling. Belts are of a rubber composition and should be given extra care. Due to the rubber shortage, belts may not be replaceable. Discarded belts should be salvaged for the war effort.

Keep all belts free from grease and oil, which cause rapid deterioration of the belt, as Well as allowing slipping. Keep them dry and clean, and if water spatters on them, wipe it off thoroughly. Dirty belts can be washed with a mild solution of trisodium phosphate and then wiped dry. If oil, grease, or other harmful substance collect on the belts, remove the material with water or naphtha and dry thoroughly.

Flat-Belt DriveFKeep belts tight enough to prevent slipping. But do not keep them so tight as to cause excessive wear on the bearings. Belts should be loose enough to permit about a half-inch play when pressed with one finger.

If a belt shows excessive wear, fraying, or splitting, it should be replaced at once. Belts stretch, and, unless the compressor has an automatic belt tightener, it will be necessary to tighten the

belt adjustment as the belt wears in. If such adjustment has been made, it will be necessary to loosen the adjustment when a new belt is installed. If a compressor uses multiple belts, all the belts should be replaced at the same time. When replacing belts, make. an, effort to get the same make and model as the one being replaced. When replacing or rotating belts, never pry or force them off the pulley, as this puts a strain on the belt which may break the outer strands. To remove belts, loosen the motor-holding bolts, so that the belts can be easily slipped on and off. When new belts are installed, check them for tightness at the end of the first two or three weeks of operation. Tighten belts by sliding the motor.

. V-Belt Drives-The very fact that Vbelts require so little care should not be allowed to encourage neglect. It is most important to keep the sidewalls of sheave grooves perfectly straight. Where walls wear out of straight, the gripping power and emciency of the V-belt will be greatly reduced.

Do not be afraid to pull V-belts tight. Stretching them slightly in adjusting tension is good for them, but check for undue stretch and sag. A slack V-belt feels dead when you thump it with your hand; a properly taut V-belt has an alive springiness. Keep all V-belts on each drive pulling in unison to maintain their united strength. Most of the stretching that will occur during the life of a set of V-belts takes place during the breaking-in period. Nevertheless, drives should receive regular, follow-up inspections for proper tension. When one or two V-belts in a set have become worn or damaged, always install a complete, scientifically matched set.

Pulleys and ShaftssPulleys must be kept in line with each other, otherwise

COOLlNG COILS are installed adiacent to the fans. Each of the two sections shown here is made up of four direcf expansion coils. Whenever heat is added or removed, the equipmenl has a coil. In many cases, the pipe will have a spiral fin wound around its outer surface; in other cases the fins are square plates. All types of coils need attention to keep them efficient and make them last. The manufacturer's procedures should be followed.


the belt will wear rapidly. If the belt seems out of line, report it to your maintenance man. If more than two belts are used on pulleys, shift the position of the belts, if one is showing unusual wear. Rotating belts in a set increases the length of service.

When shafts of the driving and driven sheaves are not parallel, V-belts on one side of the set are thus drawn tighter and pull more than their share of the load. Naturally, that part of the set is the first to wear out, robbing the full set of much of its life. While checking the parallelism of the shafts, see that the sheave grooves are in line, too. If out of line, your V-belts are being subjected to needless rubbing on their sides, wearing their covers, and building up harmful heat.

Coils of Various Kinds

Whenever heat is added or removed the equipment has a coil. In many cases, the pipe will have a.'spiral fin wound around its outer surface. Around some coils, however, the fins are square plates. All types of coils need attention to keep them edicient and make them last.

Coils for Cooling-Coils for cooling air are of both fin types. Keep coil and fin surfaces free from dust and lint, so that air may pass over them readily, and the efiiciency of the coil may be kept at a maximum. Excessively dirty coils require attention of an expert service engineer. Air-cooling coils will condense moisture from the air, so that, on hot, humid days, water will drip from the coils. Be sure that the drain and drip pan are kept clean so as to allow adequate drainage for the condensate and to eliminate odors which may result from stagnating drippings.

Coils for Heating-Coils for heating, usually of the spiral-fin type and made of copper, may be irreplaceable, and, so, should be protected at all times. The air to be heated is blown over the coils and hot water or steam is circulated inside the coils to do the heating. Keep coil surfaces free from dust, so that heat will be efficiently transferred to the air.

Air-Cooled Coil%When cooling is obtained by passing air over the coils in which is circulated the refrigerant or other material to be cooled, care is the same as given under Coils for Cooling.

Air and Water-Cooled Coils a When cooling is done by air and water, the material is circulated inside of the pipe. The outside of the pipe is sprayed with water. Air blown across the wetted surfaces of the coils evaporates the water. The heat for vaporization is taken from the refrigerant or jacket water that is to be cooled. Coils must be kept in good condition. Because water, when evaporated, may leave scaly deposit, particular attention must be paid to the water spray to prevent the formation of scale on the coils. If scale does form on the surface in large amounts, report it to your maintenance man. Make sure that devices carrying off waste water from sprays are open and operating. Some water must constantly fiow into

the drain. This spill-over prevents accumulation of diSSOIVed solids in the water.


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1945 Theatre Catalog, 4th Edition, Page 404