rack radial clearance radial force radial pistons pump radiator rake angle ram ramp range range change rapid feed rate rateable technique raw material reading head reaming rectifier bridge rectifier module reducer reducer taper reduction reference point refrigerator regulation relay relief angle repeatability resistance resolution response time restrictor return filter reverser reversing revolution revolutions per minute revolving rib ribbed ribbed hub right angle right angle plate right fitting right-hand(ed) thread rigidity rim rod rod seal roll roll rolling mill rotary table rotating chuck-jaw rotative sensor rough roughing roughness round file round thread roundness rubber rule run run running rustfree steel rustless steel