Key sinking underwater pipe HDPE

The collapse of the pipe and the diffuser is carried out basically with the own forces of nature, ie, gravity, buoyancy and air pressure.

In this article a brief description of the main elements involved is carried out before and during the collapse

.

A number of previous aspects that must be met. Below we list the most relevant.

The first thing you should be prepared, approved and published before the start are the procedures, both sequential to be executed to ensure the quality of work activities and the safe working procedure to ensure that workers do not suffer incidents or accidents during execution.

It is also important to meet the processing, signature and obtaining all permits from the relevant government agencies; verify that you have all the required tools and equipment and all are in perfect working order and finally verify that has adequate marine conditions.

Prior to the work of sinking, the pipe must be floating on the sea and contain concrete counterweights and separations in the amounts indicated in the engineering design. The sections must be linked through flanges with bolts, nuts and washers preferably stainless steel. The pipe shall be equipped with coupling flanges at each end of the long to be sunk (usually from 300 m to 600 m in length) sections. When the long stretches have been tested with test pressure and are sealed at their ends, floating with all its balances, it is said that the pipeline is ready for relocation process. The tubes will be transported to the shaft sinking through marine vessels located for this purpose.

Once the pipeline on sinking the shaft ready, proceed to introduce water and release the compressed air while providing you with a certain tension pulling.

The sink rate should be less than 0.3 meters / second, for which must control the internal pressure of the air in the pipe.

Operation is necessary sinking as a continuous process. The pipeline must be configured as “S”.

Curva de tuberia de polietileno de alta densidad.

If the sag is stopped, the elastic modulus polyethylene material decrease and the minimum bend radius is reduced analogously. This situation may cause buckling in the pipe. Sinking action of each long stretch of pipe should be carried out in the shortest time possible, usually in less than 30 minutes.

Data from the weather forecast and the waves are essential to prepare the sinking process. The wave height should be as small as possible in relation to the type of boat to be used and may not exceed one meter high during immersion of the pipe. If the action of the waves is as small as possible, increase the safety factor against damage of the tubes.

Some key ideas, in conclusion, to keep in mind for the sinking process:

Develop work procedures and job security.

• Perform detailed calculations of subsidence curves.
• The sink rate can not exceed 0.3 m / s.
• The sinking is effected as a continuous process.
• The weather conditions should be satisfactory.
• The collapse will be made with professionals who have extensive experience in this field.

By:  Ing. Sergio Elena de la empresa ELINSUBCA C.A.
Source: ELINSUBCA C.A. Works Manuals
PipeLife Manual