As we regularly brush and flush our teeth so that we can prevent the agony and unnecessary expenses of visiting a dentists, in the same way it is necessary to clean the blowout preventer regularly to prevent any disaster, during drilling operation.
Many people often wonder why blowout preventers are needed, as it is a huge equipment weighing about hundreds of tons that sits on the top of well head. Its only purpose is to shut the well in case of any emergency occurring suddenly, during drilling operation.
If you look at the inside components of the blowout preventer then you will find many number of valves, rams and annular preventers stacked inside. When the unit is closed then all the space inside the blowout preventer is sealed so that it is isolated from the pressure of the well below it or the marine pressure created, if the drilling in going under the sea.
In case the blowout preventer remains dirty then its valves can cause malfunction and in worst case scenario it may result into deadly blowout. Therefore, it is necessary that the blowout preventer is regularly cleaned and its operation is regularly checked for its correct functioning, especially before use.
How does BOP get dirty?
When drilling is done on the surface of rock, then it is very messy operation as lots of cutting of rocks and debris get created and as the drill is rotating continuously there can be fine metal debri,s too. It is almost like any ferrous cutting that you can see after milling or cutting operation in any workshop or toolroom.
All these debris and metal junk that are created will pass throw the blowout preventer and therefore some of them may remain inside hiding within the cavity of rams and other annular preventer.
Why does it become dangerous, if it remains dirty?
The metal debris that gets generated may harm the rams and annular preventers. These parts are usually made of rubber seals and if it remains accumulated then in course of time it can be reason of abrasion. This will create defect in the ram and in such case, it will lose its capability of stopping any surge of hydrocarbons which can force its ways on the surface.
How to take care of blowout preventer
To maintain proper operation of the preventer the debris and metal junks should be cleaned after these operations
- Immediately after cutting and milling of the casing
- Before you start running of the string
- Before you do the testing of the preventer
- Before starting the drilling operation.