Number 

 of Tests 



Retests 



Character 

 of Fracture 



Defects 



Permissible 

 Variations 



Marking 



47 



20. Tension test specimens for pins and rollers shall conform to the dimensions 

 shown in Fig. 2. In this case, the ends shall be of a form to fit the holders of the testing 

 machine in such a way that the load shall be axial. Bend test specimens shall be 1 x 1/2 

 inch in section. 



21. The tension test specimens shown in Fig. 2 and the 1 x 1/2 inch bend test speci- 

 men for pins and rollers shall be taken so that the axis is 1 inch from the surface; and 

 for other bars over 1 1/2 inches in thickness or diameter, midway between the centre 

 and surface. 



22. The machined sides of rectangular bend test specimens may have the corners 

 rounded to a radius not over 1/16 inch. 



23. Test specimens for rivet bars which have been cold drawn shall be normalized 

 before testing. 



24. One tension and one bend test shall be made from each melt; except that if 

 material from one melt differs 3/8 inch or more in thickness, one tension and one bend 

 test shall be made from both the thickest and the thinnest material rolled. 



25. If any test specimen shows defective machining or develops flaws, it may be 

 discarded and another specimen substituted. 



26. If the percentage of elongation of any tension test specimen is less than that 

 specified above under "Tension Tests" and any part of the fracture is more than 3/4 inch 

 from the centre of the gauge length of a 2 inch specimen or is outside the middle third of 

 the gauge length of an 8 inch specimen, as indicated by scribe-scratches marked on the 

 specimen before testing, a retest shall be allowed. 



27. All broken tension test specimens shall show either a silky or a very fine granular 

 fracture, of uniform colour, and free from coarse crystals. 



FINISH 



28. Finished rolled material shall be free from cracks, flaws, injurious seams, blis- 

 ters, ragged and imperfect edges, and other surface defects. It shall have a smooth 

 finish, and shall be straightened at the mill before shipment. 



PERMISSIBLE VARIATIONS IN WEIGHT AND THICKNESS 



29. The cross-section or weight of each piece of steel shall not vary more than 2.5 

 per cent, from that specified ; except in the case of sheared plates, which shall be covered 

 by the following permissible variations. One cubic inch of rolled steel is assumed to 

 weigh 0.2833 Ib. 



30. When ordered to weight per square foot, the weight of each lot in each shipment 

 shall not vary from the weight ordered more than the amount given in Table I. 



The term "lot" applied to Table I means all of the plates of each group width and 

 group weight. 



31. When ordered to thickness, the thickness of each plate shall not vary more 

 than 0.01 inch under that ordered. 



The overweight of each lot in each shipment shall not exceed the amount given in 

 Table II. 



The term "lot" applied to Table II means all of the plates of each group width and 

 group thickness. 



MARKING 



32. The name or brand of the Manufacturer and the melt number shall be legibly 

 stamped or rolled on all finished material, except that rivet and lattice bars and other 

 small sections shall, when loaded for shipment, be properly separated and marked for 

 identification. The identification marks shall be legibly stamped on the end of each 

 pin and roller. The melt number shall be legibly marked, by stamping if practicable, 

 on each test specimen. 



