API STD 613:2003 pdf download
API STD 613:2003 pdf download.Special Purpose Gear Units for Petroleum, Chemical and Gas Industry Services.
1.5.14 maximum allowable speed (in revolutions per minute) is the highest speed at which the manufacturer’s design will permit continuous operation.
1.5.15 maximum continuous speed (in revolutions per minute) is the speed at least equal to lO5% of the rated pinion speed for variable-speed units and is the rated pinion speed for constant-speed units.
1.5.16 mechanical rating is the gear unit rated power
(see 1.5.9) multiplied by the specified gear service factor (see
1.5.7).
1.5.17 minimum allowable speed (in revolutions per minute) is the lowest speed at which the manufacturer’s design will permit conti n UOLIS operation.
1.5.18 normal transmitted power is the power at which usual operation is expected and optimum efficiency is desired. The normal transmitted power may he equal to or less than the gear unit rated power.
1.5.19 normative: A requirement of the standard.
1.5.20 observed: An inspection or test where the purchaser is notified of the timing of the inspection or test and the inspection or test is performed as scheduled if the purchaser or his representative is not present.
1.5.21 owner: The final recipient of the equipment who may delegate another agent as the purchaser of the equipment.
1.5.22 pinion refers to the highest speed rotor.
1.5.23 profile modification: A calculated machined deviation of the pinion andlor the gear wheel tooth flank from the theoretical tooth form. It is intended to obtain a trapeziform tooth load transfer distributed evenly along the path of contact in a transverse section when the gears are operating at normal load.
1.5.24 purchaser: The agency that issues the purchase order and specification to the vendor.
Note: The purchaser may be the owner of the plant in which the equipment is to be installed or the owner’s appointed agent.
1.5.25 The rated input speed of the gear unit (in revolutions per minute) is the specified (or nominal) rated speed of its driver, as designated by the purchaser on the data sheets.
1.5.26 The rated output speed of the gear unit (in revolutions per minute) is the specified (or nominal) rated speed of its driven equipment, as designated by the purchaser on the data sheets.
1.5.27 scuffing: A form of gear tooth surthce damage which refers to welding and tearing of the tooth surface by the flank of the mating gear. Scuffing occurs when the oil film thickness is small enough to allow the flanks of the gear teeth to contact and slide against each other.
1.5.28 scuffing resistance: A measure of the oil films ability to prevent metal to metal contact of the gear set teeth in the mesh during operation.
1.5.29 shall: Used to state a mandatory requirement.
1.5.30 should: Used to slate a recommendation.
1.5.31 special purpose application: An application for which the equipment is designed for uninterrupted, continuous operation in critical service, and for which there is usually no spare equipment.
1.5.32 special tool: A tool which is not a commercially available catalog item.
1.5.33 The tooth pitting index (K) corresponds to a contact surface stress number. The tooth pitting index is used to determine a load rating at which progressive pitting of the teeth does not occur during their design life.
1.5.34 total indicator reading (TIR), also known as total indicated runout: The difference between the maximum and minimum readings of a dial indicator or similar device, monitoring a face or cylindrical surface during one complete revolution of the monitored surface.
Note: For a perfectly cylindrical surface, the indicator reading implies an eccentricity equal to half the reading. For a perfectly flat face, the indicator reading gives an out-of-squareness equal to the reading. If the diameter in question is not perfectly cylindrical or flat interpretation of the meaning of TIR is more complex and may represent ovality or lobing.
