504 



ENGINEERING MATERIALS. 



CHAP. XV. 



(d) The axis of tension and bend test specimens for pins and rollers shall be I in. from the 

 surface and parallel to the axis of the bar. Tension test specimens shall be of the form and dimen- 

 sions shown in Fig. 2. Bend test specimens shall be I by f in. in section. 



(e) Tension and bend test specimens for rivet steel shall be of the full-size section of bars as 

 rolled. 



13. Number of Tests, (a) One tension and one bend test shall be made from each melt; 

 except that if material from one melt differs f in. or more in thickness, one tension and one bend 

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



(b) If any test specimen shows defective machining or develops flaws, or if an 8-in. tension 

 test specimen breaks outside the middle third of the gage length, or if a 2-in. tension test specimen 

 breaks outside the gage length, it may be discarded and another specimen substituted. 



94 *i*44V 2V4-' ~V+ 94- 



IV. PERMISSIBLE VARIATIONS IN WEJGHT AND GAGE. 



14. Permissible Variations. 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 to apply to single plates: 



(a) When Ordered to Weight. For plates 125 Ib. per sq. ft. or over: 



Under 100 in. in width, 2.5 per cent above or below the specified weight; 

 loo in. in width and over, 5 per cent above or below the specified weight. 

 For plates under 12 Ib. per sq. ft.: 



Under 75 in. in width, 2.5 per cent above or below the specified weight; 



75 to 100 in. in width, 5 per cent above or 3 per cent below the specified weight; 



100 in. in width and over, 10 per cent above or 3 per cent below the specified weight. 



(b) When Ordered to Gage. The thickness of each plate shall not vary more than o.oi in. 

 below that ordered. 



An excess over the nominal weight corresponding to the dimensions on the order shall be 

 allowed for each plate, if not more than that shown in the following table, one cubic inch of rolled 

 steel being assumed to weigh 0.2833 Ib.: 



V. FINISH. 



15. Finish. The finished material shall be free from injurious seams, slivers, flaws and other 

 defects, and shall have a workmanlike finish. 



