FORGING PRESS 



3256 



FORK 



pieces of native copper into rough 

 weapons or implements. It de- 

 pends upon the property which 

 metals possess, some more eminent- 

 ly than others, according to which 

 they " flow " under pressure while 

 in the solid state. In its broad 

 sense it embraces all the operations 

 of shingling, cogging, and rolling 

 by which " merchant " bars and 

 plates are produced ; the works in 

 which such operations are carried 

 out, while frequently styled rolling 

 mills to-day, were originally 

 termed forges, and the term is 

 still largely retained. 



These processes involve, first, the 

 proper heating of the crude mass 

 of metal to the requisite tempera- 

 ture ; and, secondly, the use of 

 tools specially adapted to impart 

 the desired shape to the heated 

 mass of metal. They are modified 

 more or less according to the metal 

 which is to be operated upon 

 iron, steel, copper, aluminium, 

 Muntz metal. Delta metal,phosphor 

 bronze, gold or silver. The forging 

 proper will nearly always begin 

 with a reducing operation, " draw- 

 ing down " a piece of metal to a 

 smaller size. 



Thus, in the production of an ord- 

 inary stonecutter's chisel, a round 

 or a six-sided bar of steel of the 

 desired thickness will be taken. The 

 end of this bar will be heated in 

 the smith's fire, and as soon as the 

 right temperature has been reached 

 the bar will be withdrawn, the 

 heated end laid on the smith's 

 anvil and hammered out drawn 

 down until it has assumed the 

 required chisel shape. If the chisel 

 is a small one the whole operation 

 so far may be done by the smith 

 himself with his hand hammer. 

 Principal Operations of Forging 



Otherwise the chisel will be fin- 

 ished by the use of a "swage," which 

 in this case will be a flat-faced tool 

 held in a handle made of twisted 

 iron rod. The smith will lay the 

 face of this swage on the end of the 

 chisel and his helper or striker will 

 strike it with his sledge-hammer, 

 thus producing a finished surface 

 of the desired shape, free from 

 hammer marks. The end of the 

 bar will then be notched by means 

 of a smith's chisel at a distance 

 up the bar corresponding to the 

 length of the chisel desired, and the 

 piece broken off. It is not yet 

 finished, however ; it will be desired 

 to flatten out and round off the 

 blunt end of the chisel. That end 

 is therefore heated again, the 

 chisel is then withdrawn, and the 

 end hammered or knocked upon the 

 anvil, when it will be broadened 

 out more or less, as required. This 

 operation iscalled "upsetting." The 

 production of this simple article 



thus illustrates four principal oper- 

 ations of forging heating, draw- 

 ing down, cutting off, and upsetting. 



Other principal operations are 

 bending, holing, and welding. In 

 the production of a great pro- 

 peller or engine shaft which may 

 weigh 100 tons, or of a 100-ton gun, 

 the operations are essentially the 

 same. 



Drop or Die Forging 



In the modern system of drop 

 or die forging, the heated piece of 

 metal is pressed into a die, a 

 hardened steel form, by a hammer 

 falling or dropping repeatedly upon 

 the die. The hammer is worked 

 mechanically, its weight amount- 

 ing in large machines to 3,000 Ib. 

 Many of the parts of motor-cars, 

 motor-cycles, bicycles, and in- 

 numerable other articles in iron 

 or steel are now made by drop 

 forging. Bolts and nuts, screw 

 blanks and rivets are now made 

 chiefly by machine forging, in 

 which the machine takes a heated 

 bar of iron or steel, cuts off a 

 definite length, shapes the latter 

 to the form required, and ejects 

 it automatically. See Casting ; 

 Metallurgy ; Welding. 



Forging Press. Instrument 

 used in metallurgy. The increasing 

 sizes and complexity of articles in 

 malleable iron and steel required in 



Forging Press. A, A'. Base and head 

 connected by columns, a, a', a". B. 

 Stand attached to base and to upper 

 part of which tables and dies are at- 

 tached. C. Inverted platen attached 

 to ram, D, which works up and down 

 under hydraulic pressure. Platen 

 slides up and down columns. E, E'. 

 Retractor rams which pull up the 

 platen after each downward stroke. 

 F. Intensifier which puts final extra 

 pressure on ram, D, and articles being 

 made. G. Hydraulic pumps working 

 rams. H. Flanged tire of small 

 railway truck wheel receiving finish- 

 ing press. Ram, D, may make from 

 30 to 80 strokes per minute, each 

 pressing article a little nearer final 

 shape. J, J', J". Hydraulic con- 

 nexions conveying pressure to the 

 various rams 



engineering particularly, such as 

 heavy flanged plates, cranks, and 

 crank shafts, began to make their 

 production by means of the steam- 

 hammer difficult. Attention wa? 

 therefore directed to the hydraulic 

 press as likely to prove a more 

 effective appliance, and such objects 

 are now largely produced by its aid. 

 Very powerful presses, capable of 

 exerting a total pressure of 10,000 

 tons, have been built for forging 

 purposes. The illustration shows a 

 press of this character with its 

 pumps and control valve.*, adapted 

 as it stands for the production of 

 flanged wheels and other heavy 

 flanged plates by direct pressure. 



Forisfamiliation (Lat. for is, 

 outside ; familia, family). In 

 Scots law, the alienation of a 

 child from his father and exclusion 

 from further inheritance, by mar- 

 riage, by provision made for him 

 by his parents in ante-nuptial 

 settlement or other portioning, or 

 by his own renunciation of his 

 legal right to legitim (q.v. ). The 

 custom is derived from the Roman 

 law of emancipation of a son from 

 his father's power by fictitious sale 

 and manumission, by imperial 

 rescript, or by formal declaration, 

 after which the son became inde- 

 pendent (sui juris), quitted the 

 family to which he formerly be- 

 longed, and, as a general rule, lost 

 the rights of agnation. 



Fork (Lat. furca). Instrument 

 for holding or lifting. It consists 

 of a handle, terminating in two or 

 more prongs. An example is the 

 table -fork of silver or other metal. 

 A tuning fork (q.v. ) is a two-pronged 

 steel instrument which when struck 

 gives a fixed and definite note, 

 used to determine musical pitch. 

 By analogy the word is used for 

 something (e.g. a road) which 

 divides into two. 



The farm implement of this name 

 has a wooden handle and two or 

 more steel tines. The two-tined 

 kind, when large, is known as a 

 pitchfork, used for loading hay or 

 grain. Short,stout, emptying forks, 

 of similar pattern, serve for unload- 

 ing, while turning and collecting 

 forks are still smaller, but with the 

 same number of tines. Digging 

 forks possess three to five tines, 

 which maybe round, square, or flat. 

 Additional leverage is given by a 

 sharply bent neck, and a short 

 handle is preferred. Dung forks, 

 for dealing with farmyard manure 

 and litter, usually have three or 

 four curved tines of circular sec- 

 tion. Caving, cocking, or pooking 

 forks, for collecting and loading 

 short material, are somewhat 

 similar, but the tines are long and 

 wide apart, while they are con- 

 tinued backwards above the neck 



