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Welding and cutting
!"#$%&"'()*++,-./+01'2 34' 56-789:;+<=1>?@34' A12 '/5+B A123<'./.C1'DA12/<# 3<'./E!D3!F2"CGB1HI4+J2 % K ! LMNOP QRS TRR MNG@+BF+U=/ MVPWVN"#X4K :;9 MYZ:;+ +B0G!9[O WT\]ONON ^;J_H`a(+ MZMN "C$+U= bc ZVRdN"C(CCF4!S "e%&fHg<C>-*)#1>`h+'1.F2 cfHg@"C34'%& "#X4%@i+'2/j0k2:+=@Klm5*)#1>I cgH!_H`h+n_HB34' '>o;g%&i_po3C,qo%e :<h+Klm5+1krstmF5gr"> VV!C/4F -u1<$#34'G6-!C/4F<=1k2 !C/4F:+=@./gC-+1"Ck@^+1_h+'1 on_#1aCvo.C1(+:<2<w"C>kej0k23.F2 c:&!^xy'@%& "2!U^+1_!C/4F:+=@Ky_=#/gC-+1h+'1 j0k2<DV]ZzNV:;</%+{|2h+/!5 j0k23.F./.CJCk-K}$1/`.C1(+ .C1CF~r%& "#$%&'()*+ #,-./0%1 #,2#32 #/3,232/3, 3/ -4 56478969:;5<5 8=> %?@%A'BC 3F/•+D./'1w€"@4!Cp4'@I .rx"&k@•‚ƒ<Dbb„+1/ A12'1w€"@4!4'@I"CHF/I<"e%& c'1w€"@D+Cq:4/">!@B1C8r 3F/./•+@a2+"&F/^<'/v:;+v 4 3F/./•+@<p!12a2+jD+/~CFr:;+v "&F/%@;</3!F2+21;+)"'@1 ca(+ 3F/%&a2+jD+/…2"CGB1HI<'@ .rx:</†a(+e"2"…e6"> c+21;+)"JC1H‡<r<D"ˆC@ [...]... Guide Welding Operation Shade Number Shield Metal Arc Welding up to 4 mm electrode 10 Shield Metal Arc Welding (4.8 to 6.4 mm) electrodes 12 Shield Metal Arc Welding (6.4 mm) electrode 14 Gas Metal Arc Welding (Nonferrous) 11 Gas Metal Arc Welding (ferrous) 12 Gas Tungsten Arc Welding 12 Carbon Arc Welding 10 – 14 Torch Soldering 2 Torch Brazing 3 or 4 Light cutting up to 25 mm 3 or 4 Medium cutting. .. إستنشاقها بواسطة العامل. • سرعة شفط الهواء فى مهذه الشفاطات يجب أل تقل عن 001 قدم بالدقيقة 29 CFR 1910.253 Gas Welding and Cutting اللحام والقطع بالغاز • An oxyacetylene welding outfits is basically made up of: cylinders of oxygen and acetylene, regulators, hoses, and a torch • Oxygen and Acetylene are stored in separate cylinders in a high pressure, which is controlled by the regulators • Hoses... far enough away from the actual welding or cutting operation so that sparks hot slag, or flame will not reach them When this is impractical shields shall be provided • Cylinders containing Oxygen or Acetylene or any fuel gas shall not be taken into confined spaces • Oxygen cylinders and fittings shall be kept away from oil or grease, and shall not be handled with oily hands or gloves Continued • Cracking:... 10 – 14 Torch Soldering 2 Torch Brazing 3 or 4 Light cutting up to 25 mm 3 or 4 Medium cutting 25 to 150 mm 4 or 5 Heavy cutting over 150 mm 5 or 6 Gas welding (light) up to 3.2 4 or 5 Gas welding (medium) 3.2 to 12.7 5 or 6 Gas welding (heavy) over 12.7 6 or 8 Health Protection and Ventilation التهوية والوقاية الصحية • ضرورة توفير تهوية ميكانيكية لمكان اللحام ، ومعدل التهوية ل يقل عن 0002... torch tips and by the torch valves Flash Back Arrestor on the acetylene and oxygen regulators Non-return Valves on the Torch General Requirements • Under no condition shall acetylene be generated or utilized at a pressure in excess of 15 psig • Using acetylene at a pressure in excess of 15 psig is a hazardous practice Free gaseous acetylene is potentially unstable at pressure above 15 psig and could... gloves Continued • Cracking: Before a regulator valve is connected, the valve shall be opened slightly and closed immediately To clear the valve of dust or dirt • The person cracking the valve shall stand to one side of the outlet, not in front of it • Fuel gas cylinder valves shall be opened 1.5 turns and the wrench shall be left in position on the stem of the valve Safety Precautions Flashback Arrestor... explosive violence Continued • The decomposition characteristics of acetylene gas are avoided by keeping the gas in liquid solution and storing it in cylinders of unique construction These cylinders contain porous calcium silicate filler (millions of microscopic pores) and a suitable solvent usually acetone (has the ability to absorb over 400 times its own volume of acetylene at 70º F Acetylene Cylinders... spray or soap solution that there is no leakage Never expose the acetylene cylinder to strong heat A burning torch must not be hung on the regulator or expose the cylinder Adequate Ventilation Cylinders and Containers • Compressed gas cylinders shall be legibly marked, for the purpose of identifying the gas content.(stenciling – stamping) • Cylinders should be stored away from elevators, stairs, or gangways,