ISO 12149 pdf download.Bolted bonnet steel globe valves for general-purpose applications
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 7-1 :1 994, Pipe threads where pressure-tight joints are made on the threads — Part 1 : Dimensions, tolerances and designation. ISO 7-2:1 982, Pipe threads where pressure-tight joints are made on the threads — Part 2: Verification by means of limit gauges. ISO 261 :1 998, ISO general-purpose metric screw threads — General plan. ISO 263:1 973, ISO inch screw threads — General plan and selection for screws, bolts and nuts — Diameter range 0.06 to 6 in. ISO 4200, Plain end steel tubes, welded and seamless — General tables of dimensions and masses per unit length. ISO 5208, Industrial valves — Pressure testing for valves. ISO 5209, General purpose industrial valves — Marking. ISO 521 0, Industrial valves — Multi-turn valve actuator attachments.
3 Terms and definitions
For the purposes of this International Standard, the definitions of nominal size (DN) and nominal pressure (PN) given in ISO 6708 and ISO 7268, respectively, apply.
4 Pressure/temperature ratings
4.1 The pressure/temperature ratings applicable to valves specified in this International Standard shall be in accordance with those specified in ISO 7005-1 for steel flanges of the applicable PN and material specification. Restrictions on temperature or pressure, for example those imposed by soft seals and special trim materials, shall be indicated on the valve identification plate (see 8.4.2). 4.2 The temperature shown in a particular pressure/temperature rating is the maximum temperature of the pressure-containing shell of the valve. In general, this temperature is the same as that of the fluid contained. Use of a pressure rating corresponding to a temperature other than that of the fluid contained is the responsibility of the user. 4.3 For temperatures below the lowest temperature shown in the pressure/temperature rating tables in ISO 7005-1 , the service pressure shall be no greater than the rating shown for that lowest temperature. The use of valves at lower temperatures is the responsibility of the user. Consideration should be given to the loss of ductility and impact strength of many materials at low temperature.
5 Design
5.1 Body wall thickness 5.1.1 A schematic diagram of a valve body is shown in Figure 1 . The minimum wall thickness t m at the time of manufacture shall be as given in Table 1 except as indicated in 5.1 .2, 5.1 .3, and 5.1 .4. Additional metal thickness needed for assembly stresses, closing stresses, stress concentrations and shapes other than circular shall be determined by individual manufacturers, since these factors vary widely. 5.1.2 The weld preparation in butt-welding end valves (see 5.2.2.2) shall not reduce the body wall thickness to less than the values required by 5.1 .1 within a region closer to the outside surface of the body neck than t m measured along the run direction. The transition to the weld preparation shall be gradual and the section shall be essentially circular through the entire length of the transition. Sharp discontinuities or abrupt changes in section in areas that infringe into the transition shall be avoided, except that test collars or bands, either welded or integral, are allowed. In no case shall the thickness be less that 0,77t m at a distance of 1 ,33t m from the weld end.