iNPIPE PRODUCTS™ was selected to carry out unique pig design services for a client for a newly developed oil field.  The long-term export solution for the asset requires the asset to be connected to the existing subsea pipeline infrastructure leading back to the mainland. Due to the waxy nature of the crude from this field, regular operational pigging is required to maintain effective through flow.  The alternative would be to lay a new export pipeline to shore or export oil by tanker via a SAL system long term, which would be cost prohibitive.

The new 10” export line connected to an existing 14” line via a gate valve and a 10”-14” reducer. This 14” line then drops into a 24” line via a forged Tee.  The 24” line has an equal wye, which must be negotiated before a 24”-34” reducer and a second equal Wye in the 34” pipeline section.  The new bespoke design had to negotiate all the above nominal pipe sizes.

The Client’s requirements needed to ensure that the selected pig design was capable of:

• Removing wax deposits from 10” and 14” lines
• Self-transit through a section of 24” and 34” pipe work
• Ability to be pushed in front of an existing 24” or a 34” pig without ‘hang up’ issues
• Capable of successfully traversing a forged 14”- 24” Tee

iNPIPE PRODUCTS™ produced conceptual designs, which were reviewed by the client prior to testing program.  In total the new pig design had to cope with a change in nominal pipe size of 70%.  The manufacturing methodology selected was a flexi-cast, fully polyurethane design, to ensure safe negotiation of transitions.  In addition, the pig had to incorporate risk reduction features, should a pig be travelling in the larger pipe sections simultaneously.  The fully cast design also provided buoyancy in the larger pipeline diameters.

The design included a combination of disc and flexi cups to provide effective wax removal in the new production lines.  The flexi cups ensured travel through the larger ID pipeline sections, while also collapsing to the smallest size.

In addition, to control speed, reduce weight and provide jetting action in the smaller pipe sizes, the design had to incorporate a mechanical pluggable bypass system.

All design, tooling and pig production including full scale testing to replicate the line configuration was carried out at iNPIPE PRODUCTS™ Brompton on Swale facilities.

Key unique features of pig design:

Negotiate 10” flexible riser	10” pipeline (wax removal)
Negotiate 10” NRV	Negotiate 14” gate valve
Negotiate 14”-10” reducer	14” pipeline (wax removal)
Negotiate 2 x 14” ball valves	14”-24” forged T (pig drops in to 24” line vertically rotates 90deg in to flow from 24” line)
Transit through 24” pipe	Negotiate 24”- 24” Y (self-transit in flow)
Negotiate 24” pipe (self-transit in flow)	Negotiate”-34” Y (self-transit in flow)
Negotiate 34” pipeline (self-transit in flow)	Arrive at terminal

The final tools were delivered on time and on budget.

 

iNPIPE PRODUCTS™ is an internationally recognised leader in the design and manufacture of pipeline pigging products, including foam pigs, cup pigs, bi-directional cleaning / gauging pigs, pig handling equipment, pig signalers, engineered solutions for pipeline isolation and joint testing, launching & receiving systems as well as bespoke pigging solutions based on specific client project requirements.