API St 613:2003(2007) pdf download

API St 613:2003(2007) pdf download.Special Purpose Gear Units for Petroleum, Chemical and Gas Industry Services.
2.3.1.4 The equipment feet shall he provided with vertical jackscrews.
2.3.1.5 Bores shall be machined to a sufficient degree of accuracy so that a gear set that contacts correctly on true centers on a tutor checking stand will also contact correctly in its own casing.
2.3.1.6 Casings shall he designed to present damage due to distortion caused by temperature. torque. and allowable external liwces and moments.
2.3.1.7 To the maximum extent practicable. casings shall be designed with internal ad passages to minimize external piping All internal piping should preferably be welded and should preferably use flanges for all connections Any threaded piping shall be a minimum of Schedule Xt) and shall he seal welded at flanges (see 2.4.6.4).
2.3.1.8 Where internal space does not permit the use of DNI5. DN2O. or DN25 (½-. 3)4, or I-in.) ASTM A 312 pipe, seamless steel tubing conforming to ASTM A 192 with stainless steel linings. ci stainless steel tubing confonning to ASTM A 269 with stainless steel littings may he furnished, Tubing thicknesses shall meet the requirements of Table 6. The make and model of fillings shall be subject to the purchaser’s approval.
2.3.1.9 The design of internal piping shall achieve proper support and protection to present damage from sibration or from shipment operation, and maintenance. Cantilevered piping shall include reinforcing gussets in two planes at all pipe-to- flange connections,
2.3.1.10 Internal piping and oil passages shall he cleaned to rcrnos’e all foreign material.
2.3.1.11 Casings shall be designed to permit rapid drainage of lube oil and to minimize oil foaming. which could lead to excessive heat rise of the oil. For gears with prich line velocities of more than 125 ni/sec (25.1k) ft/minj, consideration shall he given to special designs such as the following:
a A false bottom in the gear unit.
b. A sump depth at least 61(1 mm (2 fU below the bottom.
c. Meshing direction.
d. An oil drain line to the reservoir that is independetit from all other drain systems
c. A second full-sized drain connection.
1. Larger side and cin.’utnfercntial clearances between gears and pinions and the casing.
g. Windage baffles.
2.3.1.12 A filter-breather shall he provided by the vendor. The filter-breather shall he constructed of Series 3W) stainless steel with Series 34 stainless steel or copper-nickel alloy (e.g.. Mooch internals, designed and located to present:
entrainment or discharge of oil to the atmosphere. pressure buildup in the casing. entrance of water during violent rain• storms, and entrance of dirt entrained in the air. The filterbreather shall be at least NI’S I ½ and its construction shall permit easy disassembly for inspection and cleaning.
Note: The Ireatiom generally recuinnwnded by gea manufiicttwers for the titter-breather is on the drain pipe immediately adjacent to the casing. with no breather on the casing itself The filter-breather may he bicatesi on the casing or the (kiln, Location of the hlierhreather shall be shown on the outline drawing
2.3.1.13 A removable, gasketed inspection cover or coven shall be prnsided in the gear casing to permit direct visual inspection of the full face width of the ptnion and gear. The inspection opening or openings shall he at least one-half the width of the gear f.
2.3.1.14 Permanent coatings or paint shall not be applied to thc interior of the casing unk%s the purchaser approses in advance the material and tnethod of application.
2.3.2 Joints
Axially split casings shall usc a metal-to-metal joint (with a suitable joint compound) that is tightly maintained by suitable bolting. Gaskets (including string type) shall not be used on the aitial joint.
2.3.3 Bolting
2.3.3.1 Case bolting should preferably be of the througb bolt type. Where this is impractical, studs shall he used unless assembly or disassembly prevents their use. Cap screws are acceptable in such instances.
2.3.3.2 The details of threading shall confornt to ISO 261. ISO 262, ISO 724, 150965 (ASME 141.1).
2.3.3.3 Studded connections shall be furnished with studs installed. blind stud holes should he drilled only deep enough to allow a preferred tap depth of 1112 times the major diameter of the stud: the first 1½ threads at both ends of each stud shall be removed.