Liquefied petroleum gas (LPG) cylinder repair

Gas cylinder repair includes following steps:

Separating the handle and base (foot)

In this stage, by special machines and new plasma system, separating the handle and base is implemented. At this point , because of the presence of old welding at the meeting point of the handle and the base, it requires more precision in order not to damage the cylinder body.

 

New base and handle assembly

Next, the cylinder will be equipped with the new handle and base. Welding a handle onto a base will be carried out by the maintaining machine. During the production of the handle, the company information and the technical specifications of the cylinder along with the standard icon in engraved.

 

Normalizing process

Normalizing is done in order to uniform the structure of the molecule of metal used for the cylinder. After passing through the pre-heating section. the cylinder enter the furnace by the air conveyor so that the flame does not collide directly to the cylinder body. The cylinder is placed at a temperature of 910 - 915 C for a certain period of time. After the completion of normalizing and passing through the wind tunnel the cylinder is transmitted to the next section.

 

 Hydrostatic test

At this stage, filling the cylinder with water and keeping it under the pressure of 35 bar in certain period of time help us to find out an possible hole (at micron level) and to remove the defective cylinder from the production cycle.

 

Shot (Shot Blast Machine)

Shot is a stage in which separation of oxidized and remnants of paint occur. At this point, the cylinders ready to be painted and enter the certain furnace.

 

Painting stage

Fortunately, we have been one of the first companies that have used electrostatic to paint the cylinders. The integral and unique beauty which is given to the product by this painting powder (electrostatic) in comparison with other methods is quite tangible. After scouring the visual test and cleaning the cylinder by air conveyor, the preheating operation is conducted. In the next step, the cylinder is painted by robots with different capabilities. Then, it is heated in the furnace at the certain period of time in order to fix the color.

 

Weighting and engraving

After fixing the paint and color, we will have weighting and engraving stage. The exact weighting of cylinder is engrave on the handle.

 

Installing Valf

After handling and cleaning the base the valf will be closed by a technical device by controlling the number of round and specified torque pressure.

 

Air test

After the installation of valf the air test is carried out and cylinder is filled with wind under the pressure of 7 atmospheres, then it is immersed in water in order to check the possible lack and flaws at this point cylinder is ready to be distributed.

 

Explosion Test

Based on standard procedure (code 473)  out of 500 cylinder one is chosen to be exploded under specify pressure condition. This step is done using spacial device.