Corrosions and leakages happen on the platform all the time. These problems happen because pipe, flanges & any steel material are exposed to extreme environments such as heat, pressure and sea water. This will cause corrosion or/and erosion to happen on both external & internal parts.
Wellhead leakage is also one of the common problems that happens due to high-pressure and high-temperature water and gas.These causes pinholes and cracks that needed to be sealed as soon as possible or it will affect the production and most importantly the safety of the platform especially when Lower explosive limit (LEL) gas detected.
Internal severe corrosion attacked by gas/high pressure such as the pinholes or cracks that occur due to high-pressure containment & long working period. Since it is the most crucial part of production in containing the pressure of oil & gas, the leakage needs to be sealed as soon as possible to prevent any severe damage in the future.
Clients need our team to do a maintenance job to seal a numbers of wellheads on their platform. The early stages of this project started from the coordination between the Sales, Engineering and Operation Team to collect and gather all the details regarding the job. Inspection found that the wellheads repair can be proceeded as we have experienced more severe cases than this which was – diameter -200mm-1200mm -design pressure(up to 1000 pSi).
For this type of repair, we need to properly investigate the leakage spot, the severity of the leakage, operating & design pressure, dimensions & design of the well, any obstruction nearby the leakage. All this information is needed in order for us to determine whether the wells need to be repaired with composite wrapping, plate bonding, Superwrap 2 wrapping or even all at once. Once the method of repair is confirmed, the most suitable products & quantity of the product can be decided.
Furthermore, we do provide non-metallic composite repair according to ASME PCC2 repair of pressure equipment and piping (add some details ASME PCC2) – For reference, Article 4.1 on Nonmetallic Composite Repair Systems: High Risk Applications; Article 4.2 on Nonmetallic Composite Repair Systems: Low-Risk Applications; and Article 5.1 on Examination and Testing.
The inspection by the Engineering & Operation teams found out that all the wellheads have pitted and leakage surrounding the wellheads. Our team has few methods of repairing the wellheads and it depends on the severity of the wellhead’s condition. Some of the wellheads can be repaired using B9611, B1212, B1161, B9341 and B5831 but if the damage or leak is severe, SW2 needs to be installed to increase the strength of the repair. Wet sponge test was also done to detect the pitted holes on the surface.
MANPOWER & APPLICATION
Our team were mobilized to the platform to seal a few of wellheads Offshore, where a wellhead is located on the production platform it is called a surface wellhead, and if located beneath the water then it is referred to as a subsea wellhead or mudline wellhead. 2 or 3 minimum manpowers are needed for each application of the wellhead.
HOW WE DID IT?
1. SURFACE PREPARATION.
The repair process is started by doing surface preparation on the surface of the wellheads using the MBX. After that, the process is continued by checking snoopy area around the well to make sure there is no leak. Then the surface is cleaned by using the TCE to clear the surface from dust and tiny debris.
2. CHECKING SURFACE PROFILE.
Our applicator will check the surface profile to make sure that it meets the minimum requirements of surface preparation before applying any products so that the adhesion strength can be guaranteed.
3. CLEANING THE SURFACE USING TCE.
To make sure that the surface is really clean, Trichloroethylene (TCE) is used as a cleaning medium because of its ability to remove dust and tiny debris on the surface of an object without making the surface oily.
4. BELZONA PRODUCTS APPLICATION
Belzona products were used to stop the leak from the pinhole or cracks on the wellhead. It is also functioned to fill the tiny gap between the edges and pores on the wellhead surface. Its fast curing system makes the application faster and easier as long as the applicators follow all the IFU.
5. FINISHING PHOTO/COMPLETION APPLICATION
The wellhead is successfully sealed with Belzona product.