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WELDER - CITS

pressure safety device, which consists of a pressure disc, which will burst before the inside cylinder pressure
becomes high enough to break the cylinder body. The cylinder valve outlet socket fitting has standard right hand
threads, to which all pressure regulators may be attached. The cylinder valve is also fitted with a steel spindle to
operate the valve for opening and closing. A steel cap is screwed over the valve to protect it from damage during
transportation. (Fig 1)

Fig 1 Fig 2

The cylinder valve has a pressure safety device, which consists of a pressure disc, which will burst before the
inside cylinder pressure becomes high enough to break the cylinder body. The cylinder valve outlet socket fitting
has standard right hand threads, to which all pressure regulators may be attached. The cylinder valve is also
fitted with a steel spindle to operate the valve for opening and closing. A steel cap is screwed over the valve to
protect it from damage during transportation The cylinder body is painted black.
The capacity of the cylinder may be 3.5m3 - 8.5m3. Oxygen cylinders of 7m3 capacity are commonly used.
Acetylene gas cylinder - charging method
Definition: It is a steel container used to store high pressure acetylene gas safely in dissolved state for gas
welding or cutting purpose.
Constructional features:
The acetylene gas cylinder is made from seamless drawn steel tube or welded steel container and tested with a
water pressure of 100kg/cm2 the cylinder top is fitted with a pressure valve made from high quality forged bronze.
The cylinder valve outlet socket has standard left hand threads to which acetylene regulators of all makes may be
attached. The cylinder valve is also fitted with a steel spindle to operate the valve for opening and closing.
Steel cap is screwed over the valve too protect it from damage during transportation. The body of the cylinder is
painted maroon. The capacity of the DA cylinder may be 3.5m3-8.5m3.

The base of the D A cylinder (Curved inside) is fitted with fuse plugs which will melt at a temperature of app.100°C.
In case the cylinder is subjected to high temperature, the fuse plugs will melt and allow the gas to escape, before
the pressure increases enough to harm or rupture the cylinder. Fuse plugs are also fitted on the top of the
cylinder.
Method of charging DA gas cylinder:

The storage of acetylene gas in its gaseous form under pressure above 1kg/cm2 is not safe. A special method is
used to store acetylene safely in cylinders as given below.
The cylinders are filled with porous substances such as:

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CITS : C G & M - Welder - Lesson 14-26 CITS : C G & M - Welder - Lesson 14-26