Boat Landing

How can shuttling costs be reduced for two aging gas platforms in the Southern North Sea?

That was the question posed by our client.

The answer: substitute helicopters for boat transfers

Pinnacle were appointed as structural engineering consultants to develop a safe and reliable boat landing in order to meet the demands of two gas platforms in the latter stages of their field life, to reduce operational costs in line with the lower production revenues from mature wells. To commence the engineering and design process we visited both platform locations by boat, with the operator, where we discussed the requirements and sketched up a concept design solution for a boat landing station which would give a secure and safe method of transferring from vessel to platform as well as being able to cope with the tidal range. With this early collaborative approach to design, we fully engaged with the OIM, Client PM and Vessel Master to outline the basis of a solution that would meet the requirements of all key stakeholders.

The principal engineering challenges were; to create a stair and landing structure fixed to the existing jacket between splash zone and spider deck – designed to be installed using the platform crane, without the need for an expensive jack-up barge. The solution had to be both robust, to cope with the environmental conditions, and easy to maintain for the platform operator.

Pinnacle designed a clamped steel structure between the jacket’s spider deck and horizontal bumper beam; suitably robust enough to manage with life in the green water zone but carefully detailed to allow its safe installation using platform crane, hoists and rope access team.

The involvement of the steel fabricators, installation and rope access companies within the structural design and detailing phase ensured that the clamps and frame were split, jointed and slung to facilitate the chosen installation contractor’s preferred method of erection. A laser point cloud survey determined accurate jacket setting out and, prior to fabrication, timber templates of the clamps were made and taken to the platform to check for fit.

The outcome of this intelligent and collaborative design process was a ‘right first time and delivered on time’ boat landing structure installed safely, without incident, in challenging conditions, commissioned and handed over without the need for any site modifications.

Pinnacle were a key component of this fully collaborative project team, from conception through to completion.