During its service to the Oman oil and gas industry for over five decades, The Oman Construction Company (TOCO) has placed itself as a symbol of ‘Operational Excellence’ in its chosen areas of business. Since 1965, the company has been a ‘Trusted Partner ‘of major national and international oil and gas asset owners and operators across the Sultanate of Oman. During this time TOCO has developed a un-paralleled level of expertise in pipeline and construction services. TOCO is part of Oman’s oil and gas legacy with several ‘Firsts’ to its credit. The list includes construction of the first major cross country pipeline, flow line, production station, tank farm, overhead power line. In 1967, TOCO moved the first rig at Fahud.
Occidental Petroleum, the operator of Oman North concessions Block 9, 27 & 62 had an aging pipeline that needed replacement. The 12 inch diameter, 16 kilometre long pipeline had over 250 leaks which were temporarily been arrested using clamps.
The pipeline integrity was under question and OXY was looking for a quick and technically sound method of installing a replacement pipeline parallel to the existing.
TOCO joined hands with NOV Tuboscope to propose an innovative patented pipe jointing system which was several times faster than the conventional welding method.
TOCO was awarded this contract on 15-Feb-2015 through a competitive bidding process.
The pipes were jointed using innovative “Mechanical Interference Joining” method:
The Zap-Lok system relies on an engineered mechanical interference connection between a cold-expanded “bell-end” and an opposing, slightly larger “pin-end”.
The process derives its strength from the metal-to-metal friction generated as the two ends are hydraulically pressed together and highly compressive forces are transferred from the bell-end onto the pin-end – permanently holding it in place.
The project:
- 16,563 meters of 12” CS pipe
- 12,160 Ltrs of paint
- 102,193 manhours
- 180 men at peak
- 1,413 joints welded
- 33 expansion loops
- 15 road crossings
- Project finished 15 days ahead of schedule!
TOCO’s scope included procurement, construction and testing of the 12” X 16.65KM Carbon Steel Pipeline.
The entire line was both internally and externally coated.
The internal coating was specialised and was carried out in Tuboscope factory in Abu Dhabi.
The project had some major challenges including the following:
- A hefty penalty for late completion
- Stringent specifications : Minimal tolerance for mechanical jointing, Internal coating quality and HSE
- Difficult terrain
- Project was executed during heat stress month with work hour regulations
- Project was executed during the holy month of Ramadan, which comes with regulations in the hours of working – more over many of our employees were fasting
- Special internal coating demanded high attention and care during handling welding
- The pre-construction works (Pinning, Belling & Internal coating ) were executed in UAE
- The new pipeline construction activities including welding was carried out in close proximity to an existing leaking live line – this demanded special arrangements in term of safe working
- Pipe were manufactured and shipped from China – the delivery schedule was hit by Chinese New year break and adverse weather for shipping
- Raw pipes were taken to Abu Dhabi for processing and processed spools had to be transported back to the site – This was a major logistics exercise considering the border formalities
- The project has faced every possible bottleneck and challenges, many out of TOCO’s control, which could have derailed the completion schedule with TOCO paying a hefty penalty and facing loss of reputation.
But with the hard work, positive attitude and perseverance of the Project Team, they were able to complete the project 15 days ahead of schedule successfully and meeting all technical specifications.
