API STD 613:2003 pdf download

API STD 613:2003 pdf download.Special Purpose Gear Units for Petroleum, Chemical and Gas Industry Services.
2.4.8 Machined and studded connections shall conform to the facing and drilling requirements of ISO 7005-I or ISO 7005-2 tASM1 1316.1. 1316.5, or B16.42). Studs and nUts shall be furnished installed, the first 1.5 threads at both ends of each stud shall be removed.
2.4.9 Threaded connections shall not be more than UN 40 (NPS I /2). Tapped openings and bosses for pipe threads shall conform to Iso 7-1 (ASME 1316.5). Pipe threads shall be taper threads conforming to ASME B 1.20.1.
2.4.10 Tapped openings not connected to piping shall be plugged with solid plugs furnished in accordance with ASMIi B 16.11. Plugs that may later require removal shall be of corrosion-resistant material. Threads shall be lubricated. Tape shall not be applied to threads of plugs inserted into oil passages. Plastic plugs are not permitted.
2.5 GEAR ELEMENTS
2.5.1 General
2.5.1.1 All gear teeth shall be finish cut or finish ground on the assembled gear and shaft. One or more of the following processes shall be used in finishing the gear teeth:
a. Grinding.
h. Shaving.
c. Honing.
d. Precision bobbing.
All gear teeth finished by shaving or honing shall have been generated by bobbing. Shaving cutters and rotary hones shall have a hunting tooth combination with the workpiece.
2.5.1.2 The tooth surface on loaded faces of completed gears shall have a finish, as measured along the pitch line, of 0.8 1.trn (32 microinch) Ra or better. See also ISO TR 1(1064-4 on measuring methods.
2.5.1.3 The design of single-helical gears shall be such that the effects of the moments on the gear elements, resulting from axial tooth reaction at the gear mesh, will not impair the expected performance of the gear unit.
2.5.1.4 Hunting tooth combinations are required. To achieve this requirement. it may be necessary for the purchaser to adjust the exact gear ratio. If such adjustment is impractical. the purchaser and the vendor shall negotiate a solution.
Note: A huniing tooth combination is required because the intent is for every tooth on a pinion to mesh with as many teeth as possible on the mating gear wheel before the same teeth mesh again or repeal.
2.5.2 Quality Assurance
2.5.2.1 After thc gcar teeth arc finish-cut. shaved, or ground on a hobbing. shaving, or grinding machine. thc gear elcmcnts will be checked per ANSI/AGMA ISO 1328-I for gear tooth accuracy. The gear elements shall have an accuracy of Grade 4 or better. 11w records of the gear accuracy check shall be maintained by the vendor for a period of not less than 20 years and shall be available to the purchaser on request.
Note: Previous journal runout chart requirement is replaced with gear chats requireineni ANSI!AGMA ISO 1328-I references the journal in the measurement of the gear teeth. Sec also IS(VTR 10064.1 ott measuring methods.
2.5.2.2 Each pair of mating gears shall be considered as a matched set and shall be checked for contact on a contact checking stand and in the job casing at the vendor’s shop. The check per 2.5.2.1 cannot be used as a replacement liw this check. A thin coating of color transfer material (such as Prussian blue) shall be applied at three locations 120 degrees apart to 4 or mote teeth of the dry degreased gear wheel. (Layout dye shall not be used for the contact check on the checking stand.) With the gear elements held firmly on the correct center distance and with the shaft centerlines parallel within 42 p.m per meter i0.()05 in.Ift) with a total misahgnrnent of not more than 25 p.m (0.001 in.). the coated teeth shall he rotated through the mesh with a moderate drag torque applied in a direction that will cause the teeth to contact on the nonnally loaded faces. The color transfer shall show evidence of contact distributed across each helix as prescribed by the vendor. Prior to the contact tests, the vendor shall make available to the purchaser a contact drawing or vendor engineering specifIcation that defines the acceptable contact.