348 



STEEL HEAD FRAMES AND COAL TIPPLES. 



CHAP. X. 



the collar of the shaft to the center of the sheaves. The mine has a four compartment shaft, two 

 of the compartments being used for hoisting ore. The mine is now 1,697 ft. deep, but the head 

 frame was designed for an ultimate depth of 3,500 ft. The ore is hoisted in five-ton self-dumping 

 skips with a single deck cage above the skip. The skips weigh 7,500 Ib. each. Four-deck cages 

 are used for hoisting men. The hoisting rope is i| in. in diameter, a round hoisting rope being 

 an innovation in the Butte district. The rate of hoisting is 2,800 ft. per minute. The skip ore 

 bins have a capacity of 150 tons. From the skip ore bins the ore runs into railroad ore bins (not 

 shown in Fig. 14), 26 ft. 9 in. wide by 150 ft. long, with a capacity of 1,500 tons. The sheaves are 

 12 ft. in diameter, and are placed 5 ft. 10 in., center to center. 



The main posts are made of two channels 12 in. @ 205 Ib., with a cover plate 16 in. wide 

 and ^g in. and | in. thick, with lacing on the inner side. The back braces for the lower two 

 panels are made of channels 12 in. @ 30 Ib., with a plate 16 in. X f in.; the third section is made 

 of two channels 12 in. @ 30 Ib., with a plate 16 in. X TS in., while the two upper sections are 

 made of channels 12 in. @ 2o| Ib., laced on both sides. The main struts and diagonal braces are 

 made of two channels, with battens top and bottom. The skip guides are made of two channels 

 12 in. @ 20^ Ib. The main girder at the top of the back brace consists of one plate 36 in. X 1 in., and 

 four angles 4 in. X 4 in. X I in. The skip bins are supported on columns made of two channels 

 10 in. @ 15 Ib., laced on both sides. Where two channels are used for a section, the flanges are 

 turned out. The New Leonard head frame is one of the highest in the country, and is one of the 

 best designed frames that has been constructed. The shipping weight of the structural steel in 

 this head frame was 346,425 Ib. 



Tonopah-Belmont Steel Head Frame. The Belmont shaft of the Tonopah-Belmont Mining 

 Co., Tonopah, Nevada, is at present 1,420 ft. deep. It has three compartments, one for the 

 ladder-way and pipes and two for hoisting. Double-deck cages of the Leadville type are used 

 for hoisting, but the use of skips is contemplated later. The head frame, Fig. u, is of the A-type, 

 and the height is 75 ft. from the base to the center of the sheaves. The hoisting drum is placed 

 100 ft. from the center of the shaft. 



TABLE IV. 



ESTIMATE OF WEIGHT OF 75-FT. STEEL HEAD FRAME, TONOPAH-BELMONT MINING Co. 



The sheave wheels are of the bicycle pattern with a diameter of 84 in. at the center of the 

 rope groove, and an over all diameter of 91 in. Each wheel has 16 spokes of if in. rolled iron 

 rods. The spokes are cast at their inner ends into two rings 16 in. in diameter and 3 in. wide, 

 so that they form integral parts of the hub, which is 12 in. in diameter and 16 in. long, while the 

 outer ends are cast into bosses on the inside of the ring. The rolled steel shafts are 16 in. in 

 diameter at the central portion with bearings 5 in. in diameter, and are 12 in. long. The rope 

 grooves are turned in hard maple blocks fastened in a recess in the rim. The total weight of 

 the sheaves is 2,950 Ib. each. 



