API 609:2004 pdf download

API 609:2004 pdf download.Butterfly Valves: Double Flanged, Lug- and Wafer-Type.
Note I When valve body liners. sleeves, or 0-ring seals act as flange-sealing surfaces, separate gaskots shouki not he used unless specifically recommended by the manufa.iurer.
Note 2: Valves with liners that extend to the gasket scaLing surfaces should be bolted up with the disc in the partially open position.
4.3.2 Facc-to-facc dimensions for doubic flanged valves are listed in Table 2-B for long pattern valves, or Table 2-C for short pattern valves.
4.3.3 Body contact faces of cast iron, ductile iron, and cast copper alloy valves that require separate gaskets shall be tinished as specified in MSS SP-6.
4.3.4 Body contact faces of steel or alloy valves that require separate gaskets shall be finished as specified in
ASMF B 16.5.
4.4 DISC CLEARANCE
The manufacturer shall design the valve disc to provide suitable clearance, in accordance with the ASME class rating for the salve, the inside diameter of the connecting pipe or Ilange. and the criteria covered in the appendix to this standard.
Note: For lug- and wafer-type valves and some double flanged designs. thc disc will project beyond the body faces when the disc is turned. The purchaser should review the design of the piping to ensure that there will be no interference between the disc and adjacent components such as the pipe lining. strainers, check valves, and other valves. During salve installation, the mating flanges shall be aligned before final tightening of the flange bolts to ensure proper valve operation and the seating of any seals and gaskets.
4.5 SHAFT AND SHAFT SEALS
4.5.1 The shaft to disc connection and all parts of the shaft within the pressure boundary shall, under torsional load. exceed the strength of the shaft that lies outside the pressure boundary by more than 10%. The determination of shaft strength shall be by calculation or testing.
4.5.2 The shaft and/or shaft retention shall be designed so that, if failure of the shaft to disc connection or of the shaft oceLirs. no portion of the shaft can be ejected from the salve as a result of internal pressure. The design shall not rely on actuation components (c.g., gear operators, actuators, levers. etc.) to prevent shaft ejection.
4.5.3 ‘The shaft-to-disc connection shall be designed to prevent loosening due to vibration.
4.5.4 For Category H salves, the shaft shall have a surface finish of 32 microinchcs (0.80 micrometers) Ra or smoother in the area in contact with the packing. and the stuffing box shall have a surface finish of l25 microinches (3.2 micrometers) Ra or smoother. Measurement may be by visual and tactiic compansun or by use of a stylus-type surface roughncss measuring instrument (AS ME B46. I).
4.5.5 Category II valves shall have adjustable shalt packing. The packing mechanism shall allow packing adjustment while (lie valve is prvssuntcd with line fluid.
4.6 PIPING CONNECTION EXTERNAL BOLT HOLES
4.6.1 Unless spccificd otherwise in thc purchasc order, tugs of lug-type valves shall he provided with tapped holes for studs or bolts.
4.6.2 Threaded body- flange holes for bolts I inch or less in diameter shall be drilled and tapped in accordance with ASME Bl.l. coarse-thread series, Class 28. For bolts I ‘I inches or more in diameter, such holes shall be drilled and tapped in accordance with ASME B LI. eight-thread series. Class 2B.
4.63 Threaded boll holes shall allow full thread engagement to a depth at least equal to the nominal bolt diameter, however, when the bolt hole is adjacent to the shalt, engagement to a depth of 67% of the nominal bolt diameter is acceptable.
4.6.4 Typical bolting options for lug- and wafer- type valves are shown in Figure 1.
4.7 SEAT RETAINER—CATEGORY B VALVES ONLY
4.7.1 Seat retainer plates (designed per Figure 2) are separate plates intended to retain and compress the valve seat and shall he mechanically fastened to the valve body. Retaining fasteners shall be recessed to or below the flange gasket.