384 



STEEL STAND-PIPES AND ELEVATED TANKS ON TOWERS. CHAP. XL 



before use, the specimens for tensile test representing such material shall be cut from properly 

 annealed or similarly treated short lengths of the full section of the bar. 



9. At least one tensile and one bending test shall be made from each melt of steel as rolled. 

 In case steel differing f in. and more in thickness is rolled from one melt a test shall be made 

 from the thickest and thinnest material rolled. 



About i8 ; ' *! 



FIG. 2. 



10. For material less than -fs in. and more than f in. in thickness, the following modifications 

 will be allowed in the requirements for elongation: 



(a) For each YS in. in thickness below j^ in., a deduction of 2\ from the specified percentage 

 will be allowed. 



(b) For each $ in. in thickness above f in., a deduction of I from the specified percentage 

 will be allowed. 



n. Bending tests may be made by pressure or by blows. Plates, shapes, and bars less 

 than I in. thick shall bend as called for in Section 2. 



12. Angles f in. and less in thickness shall open flat, and angles | in. and less in thickness 

 shall bend shut, cold, under blows of a hammer> without sign of fracture. This test will be made 

 only when required by the inspector. 



13. Rivet steel, when nicked and bent around a bar of the same diameter as the rivet rod, 

 shall give a gradual break and a fine, silky, uniform fracture. 



14. Finished material shall be free from injurious seams, flaws, cracks, defective edges, or 

 other defects, and have a smooth, uniform, workmanlike finish. Plates 36 in. in width and less 

 shall have rolled edges. 



15. Every finished piece of steel shall have the melt number and the name of the'manufacturer 

 stamped or rolled upon it. Steel for pins shall be stamped on the end. Rivet and lattice steel 

 and other small parts may be bundled, with the above marks on an attached metal tag. 



16. Material which, subsequent to the foregoing tests at the mills, and its acceptance there, 

 develops weak spots, brittleness, cracks, or other imperfections, or is found to have injurious 

 defects, will be rejected at the shop, and shall be replaced by the manufacturer at his own cost. 



17. A variation in cross-section or weight of each piece of steel of more than z\ per cent from 

 that specified will be sufficient cause for rejection, except in cases of sheared plates, which will be 

 covered by the following permissible variations, which are to apply to single plates: 



Plates weighing 12^ Ib. per sq. ft. or more: 



(a) Up to 100 in. wide, 2 per cent above or below the prescribed weight; 



(b) 100 in. wide or more, 5 per cent above or below. 

 Plates weighing less than 12 J Ib. per sq. ft.: 



(a) Up to 75 in. wide, z\ per cent above or below; 



(&) 75 in., and up to 100 in. wide, 5 per cent above or 3 per cent below; 



(c) 100 in. wide or more, 10 per cent above or 3 per cent below. 



18. Plates will be accepted if their thickness is not more than o.oi in. less than that ordered. 



19. An excess over the nominal weight, corresponding to the dimensions on the order, will 

 be allowed for each plate, if not more than that shown in Table IV, I cu. in. of rolled steel being 

 assumed to weigh 0.2833 Ib. 



Cast Iron. 20. Except where chilled iron is specified, castings shall be made of tough, gray 

 iron, with not more than o.io per cent of sulphur. They shall be true to patterns, out of wind, 

 and free from flaws and excessive shrinkage. If tests are demanded, they shall be made on the 



