ASME B16.39-2009 pdf download
ASME B16.39-2009 pdf download.Malleable Iron Threaded Pipe Unions .
3 PRESSURE–TEMPERATURE RATINGS (a) Pressure–temperature ratings are shown in Table 1 and Table I-1. (b) Unions with copper or copper alloy seats are not intended for use where temperature exceeds 232°C (450°F). (c) All ratings are independent of the contained fluid and are the maximum pressures atthe tabulated temper- atures. Intermediate ratings may be obtained by linear interpolation between the temperatures shown. (d) The temperatures shown for the corresponding pressure rating shall be the material temperature of the pressure-retaining structure. It may be assumed that the material temperature is the same as the fluid tempera- ture. Use of a pressure rating at a material temperature other than that ofthe contained fluid is the responsibility of the user and subject to the requirements of any appli- cable code. 4 SIZE 4.1 Nominal Pipe Size As applied in this Standard, the use of the phrase “nominal pipe size” or the designation NPS followed by a dimensionless number is for the purpose of identi- fying the end connection of unions. The number is not necessarily the same as the fitting inside diameter. The connecting pipe dimension can be found in ASME B36.10M.
6 MATERIALS (a) The mechanical properties of the malleable iron castings shallbe atleastequal to those specified in ASTM A 197. (b) Steel bar stock having a yield strength of not less than 207 MPa (30 ksi) may be substituted for malleable iron in NPS 1 ⁄ 8 unions. (c) Insert rings may be of suitable copper or copper alloy. Where copper alloy seats are furnished, either the head or tail part of unions produced from bar stock may be solid copper alloy. Such parts must meet the tensile strength requirements listed in Table 2 and Table I-2. 7 JOINTS AND SEATS Inserts shall be secured into the ends to become a permanent part of them with no signs of cracking. Inserted seat rings shall be of sufficient width to allow ample bearing for the seating of the male end. 8 THREADING OF PIPE ENDS 8.1 Types of Threads Pipe ends of head and tail parts shall be threaded with taper pipe threads (ASME B1.20.1) except that NPS 1 ⁄ 8 unions made from bar stock may have NPSC internal straight pipe threads. 8.2 Tolerances The variation in taper threading shall be limited to one turn large and one turn small from the gaging face of the ring and gaging notch on the plug when using working gages.
The reference point for the internal product thread is the starting end of the fitting, providing the chamfer does not exceed the major diameter of the internal thread. When a chamfer on the product thread exceeds this limit, the reference point becomes the last thread scratch on the chamfer cone. Allowance must be made for depth of counterbore on counterbored fittings. 9 HYDROSTATIC STRENGTH Assembled unions shall be capable of withstanding, without rupture or leakage through the shell or at the union joint, an internal hydrostatic pressure offive times the cold 66°C (150°F) pressure rating for 1 min. 10 TENSILE STRENGTH (a) Assembled unions shall be capable of withstand- ing, without rupture, the tensile loads shown in Table 2 and Table I-2. (b) Tests shall be conducted by attaching threaded steel bars or pipe to each end of the union using the pipe threads. Bars or pipe are to be secured in a tensile testing machine. Load shall be increased at a uniform rate until the tensile load is attained. 11 AIR PRESSURE TEST Assembled unions selected in accordance with section 12 shall be tested with air at a minimum pressure of 2.8 bar (40 psi). 12 SAMPLING FOR AIR PRESSURE TEST A random sample of unions representative of the pro- duction lot shall be submitted for testing in accordance with section 11. The average outgoing quality level (AOQL), as defined in ANSI/ASQ Z1.4, of the estab- lished acceptable sampling plans used shall not exceed 2%. A lot, for purposes of this Standard, is defined as the number of unions of the same size, design, and pressure rating submitted for testing at any one time.
