Section 5 — Piping

IPE-EP-5-3-12

IPE Engineering Practice IPE-EP-5-3-12

Document number: IPE-EP-5-3-12 · Section: 5 — Piping

CoInafsletcatilo nA Prouinbta E nEgningeeirninege Prriancgtic Pesractices Butterfly Valves for Utility Service 3) A disc position indicator shall be integrally attached to the valve stem. The stem configuration shall be such that positive alignment in the same plane for the position indicator, disc, and handle (if any) is assured. Disc and stem stops shall be provided to prevent rotation of the disc beyond the fully closed position perpendicular to the valve port axis, and beyond the fully open position, respectively. 4) (*)The stem, disc, and their connections shall be sized to develop the maximum required operating torque without exceeding ASME B31.3 allowable stresses at design temperature for the component material. For materials not included in ASME B31.3, the bases for establishing allowable stresses shall be per that standard. The Manufacturer shall submit documentation to the Owner’s Engineer for review to verify conformance with this sizing criteria. 5) (*)The valve stem shall be of one–piece construction. Two–piece stem construction is acceptable provided that the valve Manufacturer demonstrates to the satisfaction of the Owner’s Engineer that the valve design can withstand a minimum of 2000 cycles of operation under design differential pressure, without damage, leakage, or impaired operability. 6) Valve stems shall be blow–out proof if valve stem becomes separated from the disc. In addition, stems shall be blow–out proof if the stem nut becomes detached from the yoke. 7) Valves designed for connection of the shaft to an operator shall be provided with an outboard thrust bearing. The bearing may be fitted into the operating housing if the operator is furnished as part of the valve assembly and the housing is rigidly attached to the valve body. 8) Valves NPS 20 and greater size shall be equipped with two thrust bearings which hold the valve disc in the center of the valve seat. 5.8 When equipment removal or blanking is required without disturbing the remainder of the system, tapped lug–type butterfly valves or flanged butterfly valves shall be used instead of water–type valves, Lug–type valves shall be capable of holding full rated pressure with the downstream flange removed. High performance type butterfly valves per API–609 are recommended for this service. 5.9 (*)Alternative designs to that specified in this standard shall be submitted to purchaser for approval by Owner’s Engineer. Data shall include: 1) Demonstrated experience with the valve in similar service. 2) Drawings that include bolting, gasket design, and seat retainer details and a complete bill of materials. 3) Design calculations. 5.10 Rubber lining of valve bodies shall be as follows: 1) The wetted surfaces of valve bodies shall be fully lined, except that only a bonded rubber seat insert is required for non–throttled fresh water surfaces. 2) The rubber lining shall extend across the full flange face, and shall have a minimum thickness of 1/4 inch. 3) The rubber lining shall be 100% bonded to the body, flange and the metal seat insert (if any). The lining–to–body bond shall meet the AWWA C 504 seat–to–body bond requirements. The lining–to–seat bond shall be capable of withstanding a 160 psi tensile load. 4) The liner of rubber lined valves shall be oil resistant, regardless of service. 5) The minimum thickness of rubber at the body seating surface shall be as given in Table 3.

CoInafsletcatilo nA Prouinbta E nEgningeeirninege Prriancgtic Pesractices Butterfly Valves for Utility Service 8) (*)Specify materials of construction (see section 4) for the shell, trim (includes: shafts, bushings, seating surfaces on the body and disc, internal keys, pins and screws in contact with the contained fluid), seat retainer, stem packing, shaft seal, gland bolting, and gaskets. 9) (*)Specify whether unidirectional or bi–directional flow, see paragraph 4.7.3 of API 609. 10) (*)Specify whether dead end service is required, see paragraph 4.7.4 of API 609. 11) (*)Specify on–off or throttling service, see paragraph 3.4 and 4.8.1 of API 609. 12) Specify any external coating, see paragraph 8.1 of API 609. 13) (*)Specify through drilling or special tapping of lug bolt holes, see paragraph 4.6 of API 609. 14) Specify allowable gasket–surface interruptions for valve smaller than NPS 6. This needs to be agreed upon between the purchaser and the manufacturer, see paragraph 4.7.2 of API 609. 15) Specify inspection and testing requirements, see section 6. 16) Specify packaging requirements, see EP 5–3–21. 17) Specify Short Pattern face–to–face dimensions for double flanged valves if required. Long Pattern face–to–face dimensions will be supplied for double flanged valves if Short Pattern is not specified, see Table 2 of API 609. If using MSS SP–67, specify narrow or wide double flanged valve from Table 2 of MSS SP–67. 18) Specify electrical continuity if required, see paragraph 4.9 of API 609. 19) (*)Specify whether flanges are integral or welded. Owner’s engineer approval is required for welded flanges, see paragraph 4.2.3 of API 609. 20) Specify drain or bypass connections, if required, see paragraph 4.2.4 of API 609. 21) Specify a lockable device, if required, see paragraph 4.1.3 of API 609. 22) (*)Specify firesafe tested valve design per the current edition of API 607, if desired. 23) Specify stem orientation. 24) Specify buried or submerged service (if applicable). 25) Specify allowable leakage for Type II Utility valves purchased to MSS SP–67, see paragraph 11.2.2 of MSS SP–67. 26) Specify additional notes, if required.

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