Document DwBnep6Nzp8D13GjpBJ0k8qn

Wednesday, December 28, 1960 FEDERAL REGISTER 13817 to give the nip-point of the belt and covered with safety sleeves or where they 12 square feet, additional frame mem pulley the maximum protection. are used parallel with the shafting and bers shall be provided to maintain panel (c) II the cone is located less than are countersunk or else do not extend area within this limit. 3 feet from the floor or working plat beyond the flange of the coupling. (5) All joints of framework shall be form, the cone pulley and belt shall be guarded to a height of 3 feet regardless of whether the belt Is endless or laced Guard Standards roa Mechanical Power Transmission made equivalent- In strength to the ma terial of the frame. with rawhide. 50-204.168 Gears. Gears shall be guarded in accordance with one of the following specifications: (a) A complete enclosure. (b) A standard guard as described in section 204.181 at least 7 feet high ex tending 6 inches above the mesh point of the gears. (c) By a band guard covering the face of the gear and having flanges extended inward beyond the root of the teeth on the exposed side or sides. Where any portion of the train of gears guarded by a band guard Is less than 6 feet from the floor a disk guard or a complete enclosure to the height of 6 feet shall be required. 50-204.179 Muterlaln. (a) Standard conditions will be se cured by the use of the following ma terials: Expanded metal, perforated or solid metal or wire mesh on a frame of angle iron or Iron pipe securely fastened to floor or to frame of machine (see sec tion 50-204.181). <1) All metal shall be free from burrs and sharp edges. (2) Wire mesh shall be of the type In which the wires are securely fastened at every cross point either by welding, soldering, or galvanising, except In case of diamond or square wire mesh made of No. 14 gauge wire, % Inch mesh or heavier. (b) Design of guards: 50-204.180 Disk, shield, nod "II" guards. (a) Disk guard; A disk guard shall consist of n sheet-metal disk not less than No. 22 gauge fastened by "U" bolts or rivets to spokes of pulleys, flywheels, or gears. Where possibility of contact with sharp edges of the disk exists, the edge shall be rolled or wired. In all cases the nuts shall be provided with lock nuts which shall be placed on the unex posed side of the wheel. <b) Shield guards. (1) A shield guard shall consist of a frame filled in with wire mesh, expanded, perforated, or solid sheet metal. (2) If area of shield does not exceed 6 square feet the wire mesh or expanded 50-204.169 Sprockets and chains. (1) Where It Is necessary to change metal may be fastened In a framework All sprocket wheels and chains shall be enclosed unless more than 7 feet above the floor or platform. Where the drive extends over other machines or working areas, protection against fall ing shall be provided. belts, make adjustments or apply ofl or grease, guards shall have hinged sec tions or be removable. (2) Guards shall be designed so as not to Interfere with the usual machine op erations, but give the maximum protec of % Inch solid rod, % inch x % Inch x Vb Inch angle iron or metal construction of equivalent strength. (3) Metal shields may have edges en tirely rolled around a % Inch Bolld iron rod. All material of shield guard shall 50-204.170 Opening'* for oiling. tion to the operator. (c) Methods of manufacture: meet the requirements of section 50-204.181. When frequent oiling must be made, openings with hinged or sliding selfclosing covers shall be provided. All points not readily accessible shall have oil feed tubes If lubricant is to be added while machinery Is in motion. (1) Filler materia] shall be expanded metal, sheet or perforated metal, or wire mesh and be securely fastened to frame. (2> By welding to frame every 4 inches. By weaving through channel or (e) "U" Guards: A "U" guard con sisting of a flat surface with edge mem bers shall be designed to cover the under surface and lower edge of a belt, multiple chain, or rope drive. It shall be con structed of materials specified In table 50-204.171 Friction driven. (a) The driving point of all friction angle frame, or if No. 14 gauge % inch mesh or heavier is used, by bending en tirely around rod frames. of section 50-204.181 and shall conform to the requirements of sections 60204.183 and 50-204.184. Edges shall be drives when exposed to contact shall be (3) Where openings in pipe railing smooth, and If size of guard requires, guarded. (b) All arm or spoke friction drives and all web friction drives with holes in the web shall be entirely enclosed. are to be filled In with expanded metal, wire or sheet metal, the filler material shall be made Into panels with rolled edges or bound with "V" or "U" edging these edges shall be reinforced by rolling, wiring, or by binding with angle or flat Iron. (c) All projecting bolts on friction of No. 24 gauge or heavier sheet metal 50--204.181 Approved materials. drives where exposed to contact shall be guarded. 50-204.172 Keys set screws, and other projections. All projecting keys, set screws and other projections in revolving parts shall be removed or made flush or guarded by fastened to the panels with bolts or rivets spaced not more than 5 inches center to center. The bound panels shall be fastened to the railing by sheet-metal clips spaced not more than 5 inches center to center. (4) Where the design of guards re quires filled material of greater area than (a) Minimum Requirements. The materials and dimensions specified in this section shall apply to all guards ex cept horizonal overhead belts, rope, cable or chain guards more than 7 feet above floor, or platform. (For the latter, see table following section 50-204.184.) metal covers. This does not apply to keys or set screws within gear or sprocket Taim.k or Stammw Matkwai... \Nl> Himkvhiun.i casings or other enclosures, nor to keys, set screws, or oil cups in hubs of pulleys less than twenty inches in diameter Millet ini Clournucu from moving imrt ol all paint* Luruesl mesh nr opcnlnil nllamilita Minimum pause (('.. standard; or ttilckucw Minimum height of guard from floor or where they are within the plane of the platform leerl rim of the pulley. 50-204.173 Collar.,. All revolving collars, including split collars, shall be cylindrical, and screws or bolts used In collars shall not proiect beyond the largest periphery of the collar. Under a"............-- Woven v. ire... ................. Under.4."......................... Kvponiteit metal .................. /VUn"-d1e6r".4..".......................... Perforated metal......................... /Under V'........ ...... P'-lfi".................... Sheet inrlnl .............................. . /Under 4"............... 4"-lS"................... No HI.......................... 7'ir. No 10....................... 7*0". No. 12.......................... 7*0". No. 10.......................... 7*0" No. 13.......................... 7*0" Xo 20.......................... 7*0" No. 14.......................... 7V* No. 2d.......................... 7*0" N<l !.... ___ 7'0" 50-201.174 Couplings. (a) Shaft couplings shall be so con Under!"............... }i"........ Wood ,u- met.,' ,1 rip ernsvd____ U-15".............. 2"........ Wood 9i".................... Metal No. in............... 7*0" (Wood Mrt.il ..................... No. 10.. ........ jt'tr structed as to present no hazard from bolts, nuts, set screws, or revolving sur faces. Under i"............... )i" width Wood or me In I strip not erossed. 4-tS".............. l" width. r Wood Ai" ............... Motttl No, it;............... fWnod *<**.................... Mutal NO. 10............... <b) Bolts, nuts, and set screws will, however, be permitted where they are Std. nil........................................ /Min. 15" IMOI. 20".............. jse Standard fur findings Section SOt.ltU. NO. 231--Part n------ 2