Tuesday, January 15, 2013

R. Baker & Son: Oxy –Acetylene Cutting Torch Fundamentals

Oxy-fuel cutting is a process in which a combination of fuel gases and oxygen is used to cut metals with a torch.  While there are a number of fuels that can be used for torch cutting in combination with oxygen, including propane, gasoline, and propylene, the most common is acetylene.  The oxy-acetylene torch is a tool that is frequently used for selective demolition by R. Baker & Son.

Acetylene is a compound of hydrogen and carbon that has a burning temperature of 4,600 F.  When combined with oxygen, acetylene burns at 5,700-5,800 F.  Contrary to popular belief, oxygen itself is not flammable.  It is, rather, an accelerant; its presence causes materials to burn hotter and faster.  Another common misconception is that oxy-acetylene torches work by simply melting through steel. In fact, oxygen and acetylene are used to preheat the metal to its kindling temperature, at which point a stream of pure oxygen is introduced that burns the heated metal into oxide and blows it from the cut.  Oxy-acetylene torches are used for low-carbon, or mild, steel, which easily oxidize at oxy-acetylene’s burning temperature.  An oxy-acetylene torch can cut mild steel up to 12 inches thick.

An oxy-acetylene apparatus consists of two cylinders (oxygen and acetylene), each equipped with a regulator, pressure gauge, and a length of hose, and each hose is attached a torch. The angled cutting head is comprised of a central high-pressure oxygen jet surrounded by holes through which oxygen and acetylene pass to provide preheating flames.  The oxygen jet is controlled by a trigger or lever. 
To cut with an oxy-acetylene torch, the cutting head is held at a 90 degree angle to the cutting surface; using preheat jets only, the metal is heated to a dull cherry red.  Oxygen from the center jet is then triggered, instantly burning and oxidizing the iron.  As the torch is moved steadily along to produce the cut, a shower of sparks is ejected from the opposite side.  At this point, preheat jets are there purely to assist the oxidation process, and cutting proceeds at a surprisingly fast rate. 

There are numerous safety precautions that must be followed when working with an oxy-acetylene torch.  Gas cylinders must be handled properly, work areas must be properly prepared and safeguarded, and workers must be thoroughly trained.   Personal protective equipment must be worn at all times to prevent burn injuries, and special eyewear is particularly important to protect against glare and sparks while reducing the bright yellow-orange flare that oxy-acetylene cutting produces. 

Planning and preparation of the work area are important when cutting with an oxy-acetylene torch during select demolition.  Flammable materials should be removed when possible, surfaces should be shielded with welding blankets or other fire resistant guards or partitions, the area must be properly ventilated, fire extinguishing equipment should be readily available, and a fire watch must be established, among other appropriate safety procedures.  On demolition projects, careful planning is required to ensure that objects are structurally supported as cutting progresses, and sections can be removed and disposed of safely and without difficulty.

About R. Baker & Son All Industrial Services

R. Baker & Son All Industrial Services is the premier specialized contractor in the United States, Canada and Puerto Rico.  The Service-Disabled Veteran-Owned Small Businesses (SDVOSB) has been in business since 1935, has over 100 employees, an exemplary safety record (We have been directly involved in four (4) sites that received VPP OSHA Safety Awards) and is financially strong (bonding capabilities over $10 Million).  Capabilities include industrial and commercial demolition, rigging, machinery & plant moving, dismantling, decommissioning, plant and equipment relocation, interior demolition, wrecking, selective demolition , demolition contractors in NJ and warehousing.

R. Baker & Son All Industrial Services
1 Globe Street
Red Bank, NJ 07701
Phone: 732-222-3553
Fax: 732-450-0311
Web: http://rbaker.com/home.php