The March meeting was an industrial event at ICR, Bridge of Don, with group presentations and demonstrations of three of ICR’s core business activities.
ICR have specialised tooling and trained engineers, who deal with the insertion and retrieval of corrosion monitoring coupons in live pipeline valve stations (Online Retrievals).
Pre-installed fittings on the pipes allow threaded plugs which carry the mounted coupons to be inserted into the pipe.
This is carried out using either mechanical or hydraulic, telescopic portable tooling which can introduce, through the valve gate, fresh coupons of prepared carbon steel which then sit within the line for the study period. Recovery of the coupons allows for weight loss assessment and corrosion pattern studies, which can be used to evaluate the corrosive nature of the fluid and help to provide remedial measures, such as chemical injection solutions.
ICR also offers on-site weldless, flange to pipe connections which are carried out using a hydraulic colleted + ram system. The flanges to be fitted to the pipe have an annular groove in the inside into which the wall of the pipe can be expanded using tooling inserted inside the pipe end. The hydraulic ram contains a split collet which expands inside the pipe and forces a ring of the pipe wall into the flange grove. This provides a weldless metal to metal gas tight seal which is dressed each end with sealant to prevent water ingress to the junction. This can be performed on pipe to flange connections in any remote situation with 3” to 15” pipes.
A full demonstration of the operation was performed on 10” pipe using the hydraulic compressor and ram, and sectioned flanges were offered to the audience as proof of the integrity and bond.
Finally, a presentation was made on engineering repair solutions for pipe work and structural beam strengthening. These composite repairs use glass and carbon fibre cloth which is soaked in epoxy and then systematically wrapped around surface-prepared pipes, T-junctions elbows or structural beam sections, to cover and reinforce damaged or thinned areas of pipe or steelwork. The wrapping fibre used has a woven nature and anisotropic strength. Once wrapped, a compression bandage is added and within 24 hrs, the epoxy laden fibre will reach its full cured strength. The wrap system is ideal for situations were emergency or temporary repairs are required, but is often suitable for longer term fix until major maintenance programmes are permissible. ICR are also able to wrap pipes under service and low pressure which are leaking. A flanged threaded plate is fitted into the leak and a hose added to divert the leaking fluid while the pipe and edge of the plate are wrapped in the composite. Once the wrap has cured, the threaded plate can be fitted with a blanking plug to reseal the pipe.
At the close of the industrial visit, the Chairman, Dr Yunnan Gao, presented ICR with a certificate of appreciation. Further industrial visits are planned for September 2019 (NCIMB Microbial Laboratories) and March 2020 (Oceaneering NDT).
The April event was the annual joint meeting with the MCF (Marine Corrosion Forum) where the branch were very
pleased to welcome Scaled Solutions Ltd of Edinburgh, to talk on their recent R&D findings into the performance and optimization of corrosion inhibitors, including those for demanding HP (12,000 psi) / HT (300 C) operations.
(The Scottish Government recently recognised Scaled Solutions’ contribution to Research and Development through the provision of a £2.2M grant award in June 2017, to support R&D in several key areas for the Oil and Gas Production industry. This award, together with significant further investment by Scaled Solutions themselves of £3M, should bring significant cost-saving and corrosion prevention benefits to O&G operations).
It is well known that during qualification of a corrosion inhibitor, it is extremely important to carry out laboratory-based assessments that are prudently representative. However in practice, there are many variables that can contribute to the corrosive nature of a system and it is often costly and time consuming to accurately reproduce all the different field conditions. Because of this, investigations are normally carried out using an iterative screening programme, starting with simple tests, followed by product deselection and then further more complex tests. The simplified screening tests then determine the preferred products and dose rates which can pass to the next stage of testing. It is therefore vital that these initial screening tests are carried out in an appropriate a manner as possible.
Hunter Thomson explained how Scaled Solutions’ ongoing research into seemingly small changes to test methodologies and conditions in these preliminary screening tests, can significantly influence the outcome of screening studies. A range of corrosion inhibitors based on common chemistries have been formulated by them to test these effects more precisely, and their extensive results to date have illustrated the controlling effect of aspects such as pre-corrosion, the impact of the brine chemistry, inhibitor composition, as well as the effectiveness of partitioning for different chemicals, on the performance and relative performance of different products.
Hunter highlighted how relatively small changes in the methodology adopted, can lead to considerable differences in the observed performance, ranking, and outcome of the
pre-screening of corrosion inhibitor chemicals, and that thorough understanding and careful design of corrosion inhibitor screening programmes are essential to eliminating possible errors and test artefacts.
This most interesting presentation generated many questions and proposals for future work, covering topics such as effects of intermittent chemical injection, surface area and scaling.
At the close of the meeting, the chair presented Hunter Thomson with a certificate of appreciation.
Looking further ahead, the branch will be hosting its annual full-day Corrosion Awareness course on 27th August 2019, (via key sponsor Rosen), comprising of a number of lectures/presentations focusing on microbiologically influenced corrosion (MIC) in pipeline systems. This year’s programme will include talks by ROSEN specialists and other visiting speakers, on their MIC Experiences from global operations covering, sampling, analysis, monitoring of pipelines for mic damage, chemical mitigation / cleaning strategies, and finally inspection, modelling and monitoring approaches.
Most certainly this event will provide a very comprehensive introduction to this very significant and often troublesome area of Corrosion Control/Prevention, and the provisional programme can be found on the Institute website.
Full details of future ICorr Aberdeen events can be found on the diary page of the magazine and on the website, or by contacting: ICorrABZ@gmail.com, and all past branch presentations can also be found on: https://sites.google.com/site/icorrabz/resource-center
Hunter Thompson of Scaled Solutions Ltd.