IRON AND STEEL 



245 



The above grades of steel, known as structural steel for bridges and ships, 

 must conform to certain bending tests. For this purpose the test specimens 

 shall be li in. wide, if possible, and for all material f in. or less in thickness the 

 test specimen shall be of the same thickness as that of the finished material 

 from which it is cut ; but for material more than in. thick the bending test 

 specimen may be \ in. thick. Rivet rounds shall be tested full size as rolled. 



Rivet steel shall bend cold 180 flat on itself without fracture on the out- 

 side of the bent portion. 



Soft steel shall bend cold 180 flat on itself without fracture on the outside 

 of the bent portion. 



Medium steel shall bend cold 180 around a diameter equal to the thick- 

 ness of the specimen tested, without fracture on the outside of the bent 

 portion. 



STEEL AXLES 



Steel for axles shall be made by the open-hearth process and shall be 

 divided into the following classes: (a) car, engine-truck, and tender-truck 

 axles ; and (6) driving axles. For (a) no tensile tests shall be required, but 

 for driving axles the following physical properties shall be required. 



The same specifications require that one axle taken from each 

 melt shall be tested by the drop test, as follows. 



To be accepted, the axle must stand the blow without rupture and without 

 exceeding, as the result of the first blow, the deflection stated. 



