Gas cylinders?
Gas bottles are black, blue or green in most places and are a bottle of a very highly compressed substance, this means they want to be treated with care and are not to be knocked around or tipped over. if the head of one of these bottles where to be knocked off by tipping then it would turn into a very fast missile quickly. unlike acetylene gas bottles can lye on there sides although it is not recommended all the bottles you use for welding should be kept on a trolley for transport and not rolled or chucked about.
Acetylene?
Acetylene is the flammable gas which lights the torch, only with the oxygen is the flame from the torch hot enough to weld. acetylene is a gas that will displace oxygen and will catch alight so it must not be left on other than when you light the torch. the bottles must be kept stanting up and on a trolley as the liquid in the bottom of the bottle will settle otherwise and this will come if you use it on its side, this could be very dangerous. these bottles are red or maroon in color and will be the same shape and the gas.
welding hoses?
welding hoses run from the gas bottles to the torch, these are normally the color of each of the bottles and should be hooked up in the correct way. the hoses must never be left on the floor as they cause a tripping hazard and may also become damaged from people stepping on them. they should be coiled up and hung over the bottles or on a hook. if you hear of a leak in any of the hoses you should report it asap. never bend the hose so that it cuts off the circulation, this will cause build up of gas and may put unwanted pressure on the gauges.
Welding torch?
The welding torch is a simple devise that mixed the two gases and gives you your flame. this must always be hung up after use and while having a break when it is on, if not you could bump it and send a extremely hot flame falling out of control. the torch can be held any way that is comfortable for you but it must be always pointed in the general direction of you work and you must never wave it around or talk to someone while holding it.
welding tips?
Welding tips come in many different sizes and are fitted to the end of you torch, these must be cleaned out when using them regularly as molten metal can stick to them and change you welding flame. they must always be screwed on tight otherwise you may get a leak and this will start a second flame from you torch, this could be dangerous also.
Flashback arrestors?
Flashback arrestors are fitted right below the gauges, they serve the purpose of if there is a flashback in the torch and the flame travels up the hose to the bottles this devise will lock down and stop the flow, if this was not fitted the flame could go into the bottle and explode killing you. they must be serviced regularly and if one does go off than you can reset it by pushing the clip back down and you gas will flow again.
What flames are used for different metals?
There are three types of flames that are used for gas welding, the first is the neutral flame. this flame is the most common one and is used for general welding or jointing of two metals, with or without rod. for brazing you will use and slightly colder flame as the braze will melt at a colder temperature, you may also want to change the tip to a larger one if so. The last flame is used for cutting only and will not be very good at all for anything else as it is harsh and powerful and will simply burn right through the metal before you can add rod or melt the two plates together.
Welding in different environments?
There are many work situations which add to the hazards of welding. Each must be assessed carefully, since there may be added hazards such as falls or asphyxiation. This is particularly true of work in confined spaces, where there is a very real risk of death, and the employer should make a critical assessment of the work to be done, and how it may be carried out safely.
The employer needs to ensure that the lighting conditions are adequate for the work undertaken - giving extra lighting where necessary. Welders stand for long periods of time, since they must keep a very steady hand position, and this means that they can become quite cold if the workshop is not sufficiently well heated. Conversely in hot weather, the environment can become unbearably hot, and the welder has not got the option of removing clothing. Both overheating and underheating can cause fall in comfort, efficiency and productivity.
Housekeeping is extremely important to avoid slips, trips and falls, damage to equipment and fire.
Fumes?
Welding vapourises metals, and anything which is resting on the surface. This gives rise to fume, which is condensed fine particulate material. The fume is mostly oxides of the metals, including any alloying elements, but it also contains gases produced in the arc, such as ozone or oxides of nitrogen, and decomposition products from any paint or coating which was on the metal surface. The nature and quantity of this fume depends critically upon the welding process, the materials and the welding parameters. Some is harmful to health, for instance stainless steel fume contains chromium, and welding galvanised steel produces zinc fume.
WEBSITES
http://www.riegler.net/pages/02druck-temp/schweisstechnik.shop
http://www.osh.dol.govt.nz/order/catalogue/welding.shtml
www.hse.gov.uk/welding/
www.weldinginfocenter.org/health/hs_02.html
www.weldinginfocenter.org/health/index.html
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