TIS Subsea HPUs are designed to control and monitor subsea trees and associated subsea equipment during well intervention operations, and are typically accompanied by an Umbilical Reeler as part of complete Subsea Landing String (SLS) or Intervention Workover Control Systems (IWOCS). TIS Umbilical Reelers are designed to deploy and recover any length and diameter of umbilical product, with suitable controls to facilitate multiple hydraulic, chemical, electrical and fibre optic power and signal cores.

This topside controls package was used for the client’s IWOCS, typically deployed as part of a system for subsea well access and intervention operations. The PLC Controlled HPU was built and certified in compliance with DNV-ST-E271 and CE ATEX Zone 1, while the reeler was built and certified in compliance with DNV-ST-E273 and CE ATEX Zone 1.

The Hydraulic Power Unit (HP-U-1013) was built to client specification to provide both 6,000psi and 12,500psi supplies to 18 subsea lines, and was controlled via a programable logic controller (PLC). Control fluid was delivered from two 1000L supply and return reservoirs to the HP and MP circuits via four air hydro pumps, two on each circuit to provide redundancy. Two high pressure 20L accumulators and four medium pressure 50L accumulators were located in a dedicated section on the outside edge of the HPU while remaining within the unit’s envelope, for the purpose of eliminating operator exposure to risks of stored gas at pressure. The PLC was programmed with the client’s proprietary software and designed to be powered by 230V/1PH 50-60Hz supply which is connected via an uninterrupted power supply (UPS) at source.

The Umbilical Reeler (TU-A-1037) was purpose built to suit the client specified umbilical’s cores comprised of 12 hydraulic lines, five chemical line, and three electric cables (each with four conductors). A traverse spooling head sub-assembly was designed specifically to suit the umbilical OD, with two stainless steel endless screws synchronising the distance the spooling head travels per rotation of the reel to provide perfect even wraps to the drum. An inverted arch sheave on the top of the spooling head uses rollers to ensure that the umbilical does not exceed its bend radius if spooling off at a steep incline. A large marine duty disc brake with fully adjustable braking force allows line pull value to be set so that the reel will slip to protect the safe working load of the umbilical.

The Umbilical Arch Sheave (SH-A-1015-1) was designed to match the minimum bend radius of the umbilical, with rollers machined to match outer diameter, both measures to prolong the lifespan of the umbilical. Spring loaded fixtures provide a quick release function for the umbilical and a hinge section on the lift point allows for the umbilical to loaded or removed while the sheave is suspended.

The Transportation Basket (TR-A-4004-1) was designed for the transportation and storage of the umbilical arch sheave, as well as all deck jumpers, clamps, test plates and subsea jumpers related to the system.