SPECIALIZED VOCABULARY

*Air belt

the chamber which equalizes the pressure that is blasted into the cupola at the tuyures.

*Air brake

an energy-conversion mechanism activated by air pressure and used to retard,stop,or hold a vehicle or,generally,any moving element.

*ball bearing

an antifriction bearing permitting free motion between moving and fixed parts by means of balls confined between outer and inner rings.

*Chamshaft

a rotating shaft onto which one or more irregularly shaped parts(cams) are fitted.the cams give a reciprocating motion to mechanical parts in contact with them. A camshaft is used to operate the valves of an internal-combustion engine.

*Chain wheel

a toothed disc that connects with a roller chain and transmits motion when it rotates.

*clutch

a device that joins together or disconnects two revolving shafts, as required. He clutch in a motor vehicle transmits the drive from the engine to the gearbox.

*Chuck

a device with adjustable jaws,used to hold a workpiece in a lathe or a tool in a drilling machine.

*cylinder-head gasket

the gasket used toseal the cylinder head of an engine to the cylinder block.

*disc brake

an efficient type of brake in which two pads

(brake pads) close onto a disc attached to the wheel hub.

*emery wheel

a grinding wheel consisting of emery powder bonded with a resinous material.

*exhaust valve

see internal-combustion engine.

*flame cutting

a method of cutting metal using a blowtorch.

*gearbox

a train of gear wheels and its housing;e.g. The device in a motor vehicle that drives the propeller shaft at a suitable speed.

*gudgeon pin

a cylindrical bar used to secure a piston to the small end of a connecting rod.

*grinding wheel

an abrasive wheel used for grinding. It may be manually or mechanically driven.

*half round file

a file that in cross section has one flat and one rounded face.

*half shaft

a splined shaft in a motor vehicle that carries the drive from the differential gear to the driving wheel.

*house clip

a clip used to attach a hose to a source of water supply.

*hydraulic jack

a device used to raise heavy weights short distances.it is operated by liquid pressure.

*mole wrench

a type of wrench in which the jaws can be clamped in any position.

*milling machine

a machine toolused for milling metal objects to smooth or shape them.

*nut

a square or hexagonal ring of metal with an internal screw thread enabling it to be screwed nto a bolt.

*philips screwdriver

a screwdriver with a cross-shaped point for use with philips screws.

*pincers

a tool wth curved bevelled jaws,used for extacting nails.

*pipe wrench

an adjustable spanner with serrated jaws,used to turn pipes or rods.

*ring spanner

a spanner with a notched ring that exactly fits around the nut to be turned.

*timing chain

a chain that drives the camshaft from the crankshaft in an internal-combustion engine.*water-cooled engine

an engine that cooled by the circulation of water through pipes surrounding the engine.

Mechanical Abbrevations

ACU A ADJ AFF AFMS AHU AS ATC AP APD AV B BDD BFP CAP CD CFH CFM CH CLG CMU CO CRU CUH CV CW DWH DX EA EAT, LAT EF EFF EH EG EGT EL ER ESP, TSP ET EVAP EWC EWH EWT, LWT EX, EXIST EXH FD FCU FIN FLA FLR FM FPVAV FPM FS FT G GAL GALV GPM H HB HC HD HP HT HWR, HWS HV HZ IH L LBS/HR MAU MAX MBH MFR MIN M.O. MOD MTD NC NF NIC NO No NTS OA OPNG OS&Y P PCW PD PH PRV PS PSI PSIG PTHP RA RAF RG RH RL RP RPBFP

AIR CONDITIONING UNIT ACCESS DOOR ADJUSTABLE ABOVE FINISHED FLOOR AIR FLOW MONITORING STATION AIR HANDLING UNIT AIR SEPARATOR AUTOMATIC TEMPERATURE CONTROL ACCESS PANEL AIR PRESSURE DROP AUTOMATIC AIR VENT BOILER BACK DRAFT DAMPER BACKFLOW PREVENTER CAPACITY CONDENSATE DRAIN CUBIC FEET PER HOUR CUBIC FEET PER MINUTE CHILLER CEILING CONCRETE MASONRY UNIT FLOOR CLEANOUT COMPUTER ROOM UNIT CABINET UNIT HEATER FLOW COEFFICIENT COLD WATER, POTABLE DOMESTIC WATER HEATER DIRECT EXPANSION EACH ENTERING/LEAVING AIR TEMPERATURE EXHAUST FAN EFFICIENCY EXHAUST HOOD EXHAUST GRILLE ENTERING GLYCOL TEMPERATURE ELEVATION EXHAUST REGISTER EXTERNAL/TOTAL STATIC PRESSURE EXPANSION TANK EVAPORATOR ELECTRIC WATER COOLER ELECTRIC WATER HEATER ENTERING/LEAVING WATER TEMPERATURE EXISTING EXHAUST FLOOR DRAIN FAN COIL UNIT FINISHED FULL LOAD AMPERES FLOOR FACTORY MUTUAL FAN POWERED VAV BOX FEET PER MINUTE FLOW SWITCH FEET NATURAL GAS GALLONS GALVANIZED GALLONS PER MINUTE HIGH HOSE BIBB HEATING COIL HEAD HORSEPOWER HEIGHT HEATING WATER RETURN, SUPPLY HOT WATER, POTABLE HOT WATER CIRCULATING, POTABLE HEATING AND VENTILATING UNIT HEAT EXCHANGER HERTZ RPM INTAKE HOOD RTU INCH SA INVERT SD KILOWATT SAF LENGTH SAR, SR POUNDS PER HOUR SF MAKE UP UNIT SAN.W MAXIMUM SENS 1,000 BRITISH THERMAL UNITS (BTU) PER HOUR SG MANUFACTURER S/M MINIMUM SP MASONRY OPENING SQ MOTOR OPERATED DAMPER SR MOUNTED S/S MANUAL AIR VENT STL NORTH T NORMALLY CLOSED TG NON FREEZE TDH NOT IN CONTRACT TEMP NORMALLY OPEN THICK NUMBER TOD NOT TO SCALE TP OUTSIDE AIR TPV OPENING TW OUTSIDE SCREW & YOKE TYP PUMP UH PROCESS COLD WATER UON PRESSURE DROP V PHASE VAV PRESSURE REDUCING VALVE VB PRESSURE SWITCH VEL POUNDS PER SQUARE INCH VFD POUNDS PER SQUARE INCH (GAGE) VTR PACKAGED TERMINAL HEAT PUMP W RETURN AIR W/ RETURN AIR FAN WB RETURN GRILLE W.C. RELIEF HOOD WG RAIN LEADER WH RADIANT PANEL WHA REDUCED PRESSURE BACK FLOW PREVENTER