Document Mk6qb9BXrqq1q4BXDBaYO4ma

608 CHAPTER 27 1954 Guide Table 2. Dimensions and Properties of Copper Tube (Based on ASTM B-SS) Pipe, Fittings, Welding 609 copper and brass pipe have always been used in heating, ventilating, and water supply installations, but the cost with standard dimensions for threaded connections has been high. The introduction of fittings which permit erection by soldering or sweating, allows the use of pipe with thinner walls than would be possible with threaded connections, thereby reducing the cost of installations. COMMERCIAL PIPE DIMENSIONS Commercial pipe dimensions are covered in the following specifications of the American Society for Testing Materials: (1) steel--ASTM A-120 and A-53, (2) wrought-iron--ASTM A-72, and (3) copper tube--ASTM A-88. Tables 1 and 2 are based on these specifications. In addition to the specifications for these three materials, there are * Weight pPerrefsosou,tleis*5bbaasseeddoonnttuhbeinAgmweriitchaonuSttcaonudpalirndgCs.ode for Pressure Piping, published by the ASUS, revised November, 1952 ior plain eBd tubing (sweat joints). p= tc/here P =* allowable pressure, pounds per square inch. & ~0-8fm n -- 5125 psi allowable fiber stress, pounds per square inch, tm = minimum wall thickness, inches. Since copper tubing will be subject to Da c=ermtaainxiammuomun0t.oDl a.,ninnechaelins.g when heated joints are made, Since copper tuDmg win ue buujw* ____ _ fiber s*tre-s-s- is Ib--a-s--e-d- on AaTnsnresoanlel*/d} tlulbbiinfgf at 250 F. Types K and L furnished in both hard and soft tempers, Type M in hard only. Standard straight lengths are 12 and 20 ft. Standard coils (H to 1H inch) are 60 ft. Table 3. Table of Availability for Steel Pipe Material Specification Available Sizes (Inclusive) Inches Diam. Allowable Fiber Stress S* psi Butt-weld Bap-weld Electric-resistance Seamless A-120 A-53 A-120 A-53 A-53 Grade A A-53 Grade B A-53 Grade A A-53 Grade B A-120 lito 4 H to 4 2 to 12 2 to 24' 2 to 24 2 to 24 2 to 24 2 to 24 2 to 12 6,225 6,750 8,400 9,000 10,200b 12,750** 12,000 15,000 10,400 ' For use in the equation P >= 25 (tm --c) 3 dm -c) See American Standard Code p t ,ressure Piping, pub- Mhed ASME, revised November, 1952. Where P -- working pressure, pounds per square inch. 8 = fiberstress, pounds per square inch. = 0.875 x wall thickness, inches. D = O. D., inches. c = joint factor = 0.05 for 1-in. and smaller size or 0.085 for larger than 1-in. size. lor electric resistance welded pipe for applications where the temperature.is below 650 F, and where Pipe furnished under this classification is subjected to supplemental testa and/or heat treatments as agreed to by the supplier and the purchaser, and whereby such supplemental tests and/or heat treatments demon* *t*ate the strength characteristics of the weld to be equal to the minimum tensile strength specified for the pipe, the 5 values equal to the corresponding seamless grades may be used. standards for copper or brass IPS, clay or concrete, and cast-iron pipe. Copies of the following specifications may be obtained from the American Society for Testing Materials: (1) steel, wrought-iron and cast-iron---Series A, (2) copper and brass--Series B, and (3) clay and concrete--Series C. Table 3 lists the sizes available in each of the specifications and classes steel pipe.. Note that butt-weld is not available above 4-in. size and that lap-weld, electric-resistance-weld, and seamless are not available be low 2-in. size. . Listed in Table 3 is the formula for allowable working pressures as given 'n the American Standard Code for Pressure Piping. In this formula is a factor c, which is intended as an allowance for corrosion, mechanical in- l^y, manufacturing tolerances, etc. At times this factor seems too con servative; for example, with J-^-in., Schedule 40, steel pipe, the allowable wrking pressure is 314 psi. Yet this pipe is tested at 700 psi. The reason-