Forge-Practice and Heat Treatment of Steel

Author: John Lord Bacon

Publisher: Theclassics.Us



Page: 76

View: 609

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1919 edition. Excerpt: ...used in cutting, pressing, bending and the various other processes involved in working metals into marketable condition. The high-carbon steels require extreme care in the various heat-treating processes, and their use is discouraged by some on this account. The arguments advanced against its use appear to a skilled man without foundation, because men skilled in this branch of work can be had if they are given the necessary inducements. The higher the carbon the lower the critical point of the steel. If the operator bears this fact in mind he will have no trouble in determining the proper heats to employ in forging, annealing and hardening high-carbon steel. The idea entertained by some manufacturers that they must use a steel that fits the ability of their employees seems to be without proper foundation. It is better to use steel suited to requirements, and then employ workmen capable of properly treating it. The percentage of carbon is many times denoted by the term "temper." When used in this connection it has no association with the "letting down" process known as drawing the temper after hardening. The following table gives the uses of steel of various carbon contents as adopted by at least one manufacturing concern, and conforms very closely to general usage. It cannot be regarded as absolutely correct under all conditions, but answers as an approximate guide. orffi! Tools. 1.60 Tools requiring extreme hardness where toughness is not essential, for cutting partially hardened forgings, etc. 1.50 Turning hard metals, turning chilled rolls, etc. 1.40 Turning hard metals, corrugating tools, brass working tools and where a fine edge is required in connection with light cuts. 1.30 General tools for lathe work, cold...

Reinventing the Propeller

Author: Jeremy R. Kinney

Publisher: Cambridge University Press


Category: History

Page: 393

View: 391

This book explores a technology that transformed airplanes into safe, practical tools of war and a means of transportation during the first half of the twentieth century.