There are wells shut in because of damaged completion components which hinder their production control or integrity, or prevent a remedial intervention from being carried out. Often, the option to pull the completion has inherent risks from an operational, environmental and/or reservoir damage perspective and require extensive resources and time to execute. Rectifying completion component damage through a light but effective in-well intervention solution offers highly valuable options to reinstate production from such wells. This paper will discuss the rapid engineering development of an expander tool run in conjunction with an electric line deployed electrohydraulic mechanical stroker tool. Through a simple but highly-effective design, an expander tool was engineered to harness and magnify the axial force delivered by the stroker to generate a radial expansion with a force magnitude sufficient to prize out a defect in a completion component. Critical to the design was a precise measurement and control of the expansion extent and the radial force exerted, so the component in question and the other components of the completion were not damaged. This toolstring combination, coupled with real-time control and surface readout of key tool parameters, enabled a precise and measured high-magnitude expansion capability to be deployed in two different wells with ease, at pinpoint depth, and applied repeatedly across the length of the defect it was addressing. Furthermore, immediate validation of the repair was available through a drift verification pass. In both cases the in-well repair operation eliminated the need for a high cost, high risk completion retrieval and the repair operation was executed flawlessly in hours, enabling the subsequent intervention operations to be carried out and the wells be brought back on line with positive production results. The tool development was an exemplary case of rapid-response engineering, whose ingenuity stemmed from a direct customer request to solve a challenging completion defect. It resulted in a world first for an electric line deployed in-well expansion solution, the resulting value of which was well acknowledged by the customer.

Barium Sulphate (BaSO4) scale is classified as a hard scale and removal is extremely resistant to both chemical and mechanical methods. Coiled-tubing deployed mechanical intervention is effective, but with inherent logistics, footprint and cost implications. Electric-line deployed wellbore cleanout systems have the advantage of being light and easily deployable. In wellbores with inside diameters (ID) of less than 3 in., removal and downhole collection of hard debris has proved to be a particular challenge. This paper describes a wellbore cleanout operation on powered electrical wireline in the North Sea. The main operational objective was to clear out the wellbore to the top of a suspected malfunctioning Sliding Side Door (SSD), with a drift ID of 2.797 in. Access was required to run a tubing punch to establish communication with the target reservoir and therefore restore well production. The debris severely plugging the wellbore was predominantly BaSO4 scale. Slickline broaching was initially attempted to remove the obstruction, but could not make sufficient progress. An electric-line deployed wellbore cleanout system, with bottomhole assembly (BHA) outside diameters (OD) of 2.625 in. and 2.75 in. and reservoir chamber OD of 2.5 in. was subsequently deployed, which was effective and consistently able to interact with, and remove to surface, the scale blockage. 168.6 litres of debris was collected by the electric line wellbore cleanout system. Contributing to the success of the operation was extensive pre-job testing and measurements executed in the laboratory. These simulated downhole completion geometry and expected debris condition and interaction. The pre-job test results fed in to the design of an optimum BHA and were a basis for decision-making during the operation. The resulting system design maximised solids recovery per run, which increased cleanout and collection efficiency. A surface wellsite washout system was used to clean out the collection chambers, which enabled the rapid turnaround of equipment in-between runs. Cleanout was executed through multiple runs, with the majority returning maximum fill to surface, which ultimately gained access to target depth as efficiently as possible. A multi-finger caliper log run confirmed the removal of the obstruction and a tubing puncher was run to perforate the inner tubing. Production was restored, with an average (over the first three months) oil production rate of 1,290 STB/D (205 Sm3/d), gas rate of 7.2 MMscfd/D (204,321 Sm3/d) and water cut of 69%. This is the first time that an electric-line deployed wellbore cleanout system with an OD as small as 2.625 in. has delivered high, successive, repeatability in cleaning out hard BaSO4 scale from a completion with an ID as small as 2.797 in.

A well with a malfunctioning tubing retrievable sub surface safety valve (TRSSSV) was shut in until a lock-out operation could be undertaken, one which would secure the valve in a fully open position, enabling subsequent intervention programs to be carried out and the well put safely back on production. The TRSSSV design utilized a flapper valve with a power spring mechanism which forces the valve to a normally closed position. Control to the flapper had been lost as the hydraulic communication had been cut off. Repeated attempts to lock open the valve using the conventional lock out tool were unsuccessful, with its flapper returning to the closed position over time. The innovative solution presented in this paper was to engineer a simultaneously operated dual stroker electric line toolstring assembly, one leveraging several technology elements and executing several steps in a single run operation: (1) to position the work string correctly prior to engaging with the TRSSSV flow tube, (2) to operate the upper stroker to provide the axial force and stroke distance required to push the flow tube down to fully open the TRSSSV and hold it there until "locked", and (3) to simultaneously operate the lower stroker with expander adapter and dimple tool, to deform the valve flow tube and integral lock out sleeve when in a precise and predetermined position and in doing so permanently locking the valve in the open position. Carrying this out as a single trip operation would ensure the dimpling occurred only with the flow tube in the exact required "valve open" position. Individual communication & control and power sharing of both strokers was maintained throughout the operation using two surface computers in a master/slave configuration enabling a simultaneous coordinated operation. A NOGO sleeve was incorporated into the toolstring which aided precise depth correlation and space-out. Unhindered access for the subsequent intervention runs was ensured by using an eight arm multi-dimple device to prevent any ovalization of the flow tube during deformation. Force and distance limits for each stroker were set accordingly to ensure precise positioning during all phases of the operation such that no inadvertent forces would be applied to the TRSSSV. The job was executed following thorough pre-job design and verification tests. The pre-determined stroke force and distance requirements of the upper stroker to shift the TRSSSV into the open position, and those required from the lower stroker to expand the dimple tool and deform the flow tube to the pre-requisite extent, were applied and measured in real time. Some initial electric line runs were also carried out as part of the overall operation, namely a broach and a brush for cleaning possible scale accumulation. Following the successful lockout, the required diagnostic logging was completed, a straddle deployed to hold a wireline retrievable subsurface safety valve, and the well brought back into production.