216 STEEL RAILWAY BRIDGES. CHAP. IV. 



118. Rivet Holes. When general reaming is not required, the diameter of the punch shall 

 not be more than rs-'m. greater than the diameter of the rivet; nor the diameter of the die more 

 than |-in. greater than the diameter of the punch. Material more than f-in. thick shall be 

 sub-punched and reamed or drilled from the solid. 



119. Punching. Punching shall be accurately done. Drifting to enlarge unfair holes will 

 not be allowed. If the holes must be enlarged to admit the rivet, they shall be reamed. Poor 

 matching of holes will be cause for rejection. 



120. Reaming. Where sub-punching and reaming are required, the punch used shall have a 

 diameter not less than ^-in. smaller than the nominal diameter of the rivet. Holes shall then be 

 reamed to a diameter not more than r^-in. larger than the nominal diameter of the rivet. (See 



I35-) 



121. Reaming after Assembling.* [When general reaming is required it shall be done after 

 the pieces forming one built member are assembled and so firmly bolted together that the surfaces 

 shall be in close contact. If necessary to take the pieces apart for shipping and handling, the 

 respective pieces reamed together shall be so marked that they may be reassembled in the same 

 position in the final setting up. No interchange of reamed parts will be permitted.] 



122. Reaming shall be done with twist drills and without using any lubricant. 



123. The outside burrs on reamed holes shall be removed to the extent of making a i^-in. 

 fillet. 



124. Assembling. Riveted members shall have all parts well pinned up and firmly drawn 

 together with bolts, before riveting is commenced. Contact surfaces to be painted. (See 152.) 



125. Lattice Bars. Lattice bars shall have neatly rounded ends, unless otherwise called for. 



126. Web Stiffeners. Stiff eners shall fit neatly between flanges of girders. Where tight 

 fits are called for, the ends of the stiffeners shall be faced and shall be brought to a true contact 

 bearing with the flange angles. 



127. Splice Plate and Fillers. Web splice plates and fillers under stiffeners shall be cut to 

 fit within f-in. of flange angles. 



128. Web Plates. Web plates of girders, which have no cover plates, shall be flush with 

 the backs of angles or project above the same not more than f-in., unless otherwise called for. 

 When web plates are spliced, not more than j-in. clearance between ends of plates will be allowed. 



129. Floorbeams and Stringers. The main sections of floorbeams and stringers shall be 

 milled to exact length after riveting and the connection angles accurately set flush and true to 

 the milled ends f[or if required by the purchaser the milling shall be done after the connection 

 angles are riveted in place, milling to extend over the entire face of the member]. The removal 

 of more than ^-in. from the thickness of the connection angles will be cause for rejection. 



130. Riveting. Rivets shall be uniformly heated to a light cherry red heat in a gas or oil 

 furnace so constructed that it can be adjusted to the proper temperature. They shall be driven 

 by pressure tools wherever possible. Pneumatic hammers shall be used in preference to hand 

 driving. 



131. Rivets shall look neat and finished, with heads of approved shape, full and of equal 

 size. They shall be central on shank and grip the assembled pieces firmly. Recupping and 

 calking will not be allowed. Loose, burned or otherwise defective rivets shall be cut out and 

 replaced. In cutting out rivets, great care shall be taken not to injure the adjacent metal. If 

 necessary, they shall be drilled out. 



132. Turned Bolts. Wherever bolts are used in place of rivets which transmit shear, the 

 holes shall be reamed parallel and the bolts shall make a driving fit with the threads entirely 

 outside of the holes. A washer not less than |-in. thick shall be used under nut. 



133. Members to be Straight. The several pieces forming one built member shall be straight 

 and fit closely together, and finished members shall be free from twists, bends or open joints. 



134. Finish of Joints. Abutting joints shall be cut or dressed true and straight and fitted 

 close together, especially where open to view. In compression joints, depending on contact 

 bearing, the surfaces shall be truly faced, so as to have even bearings after they are riveted up 

 complete and when perfectly aligned. 



135. Field Connections. Holes for floorbeam and stringer connections shall be sub-punched 

 and reamed according to paragraph 120, to a steel templet not less than one inch thick. $[If 

 required, all other field connections, except those for laterals and sway bracing, shall be assembled 

 in the shop and the unfair holes reamed; and when so reamed the pieces shall be match-marked 

 before being taken apart.] 



136. Eye-Bars. Eye-bars shall be straight and true to size, and shall be free from twists, 

 folds in the neck or head, or any other defect. Heads shall be made by upsetting, rolling or 

 forging. Welding will not be allowed. The form of heads will be determined by the dies in use 



* See Addendum, clause (d). 

 f See Addendum, clause (f). 

 j See Addendum, clause (e). 



