Dismantling and Disposal of Six Stothert and Pitt DD2 Dockside Cranes

There has been a port in Bristol since Roman times providing a vital connection between England and the world; this proud shipping tradition continues today. Throughout the Industrial Revolution, ships were built larger to carry more cargo, so Avonmouth Dock opened in 1877 to handle the largest of ships at the time and in 1908 Avonmouth Docks were extended and the Royal Edward Dock was opened by His Majesty King Edward VII.

Surprising as it may seem, the method of handling ship cargo as late as the nineteen-fifties was not so different from that used during the time of the Phoenicians. The time and labour required to load and unload ships increased substantially with the size of the ship causing them to spend more time in port than at sea. At this time goods were usually handled manually as break bulk cargo. Throughout the twentieth century many innovations were introduced by Bristol City Docks to make the labour intensive, expensive and slow operation more efficient. This saw significant investment, and the popularisation of dockside cranes able to efficiently move cargo from quay to vessel in wooden crates, pallets, boxes, barrels or simply wrapped in sheets.

However, in 1959, a significant event occurred. A ships turnaround time (the time required to load and discharge cargo) was cut from as much as 3 weeks to as little as 18 hours. Containerisation would bring about the revolution in intermodal freight transport using standard size ISO shipping containers. Containerisation eliminated manual sorting of most shipments and the need for dock front warehouses. Containerisation reduced congestion in ports, significantly shortened shipping time and reduced losses from damage and theft. One element, however, stands out as a major contributor. The development of the STS Container Crane, the world’s first high-speed, dockside, container handling cranes.

This modern shipping method that continues to thrive today had left many old dockside cranes surplus to operational requirements many of which fell into a state of disrepair. Several dockside cranes were adapted to serve a new purpose, such as loading and unloading of bulk cargo via a bucket attachment. This was the case for the newest of the Stothert and Pitt Dockside Cranes at Avonmouth Docks, but in recent years these legacy machines were unable to compete with the latest modern equipment used today, and in 2021 the Bristol Port Company took the decision to dispose of the last six remaining Stothert and Pitt DD2 cranes within Avonmouth Docks.

Following a competitive and robust tender process, O’Brien Specialist Crane Services were selected as the Bristol Ports Company’s preferred contractor for the disposal project of the DD2 cranes. This decision was based not only on the competitiveness of our financial proposal, but also the unmatched experience of O’Brien SCS.

O’Brien SCS have completed the dismantling of countless Stothert and Pitt DD2 dockside cranes, and as a result the methodology and execution of the works was tried, tested and perfected. Nevertheless, our team recognises how important it is not to become complacent, therefore a full and robust survey and evaluation was undertaken on each of the cranes to ensure that no unforeseen eventualities would arise.

The biggest challenge on this project was the location of the cranes within the Hinkley Point C Terminal and close proximity of an adjacent storage warehouse. The Hinkley Point C Terminal is a facility specifically setup to offload, store and handle out of gauge and standard cargo for HPC. As all equipment destined for HPC is highly valuable and sensitive, security of all aspects of the supply chain are highly controlled, therefore any persons involved in the handling, storage, or even working within close proximity of such equipment must be “Hinkley Point C Compliant”.

The equipment stored within S Shed located on the HPC Terminal and within meters of the dismantling site, was considered so valuable and sensitive, the building had independent around the clock security patrol. In order for the disposal operation to be “Hinkley Point C Compliant” stringent conditions were imposed on the project. A strict exclusion zone was enforced around S shed which prohibited any parts of the works from taking place within 10 meters of the storage facility, this left only a very narrow working area of 20 meters wide in which to carry out the dismantling. In addition to this, fumes and vibration were also a concern as these could lead to damage of the sensitive equipment. This meant that hot works and mechanical scrap cutting had to be limited and strictly controlled.

The O’Brien SCS engineers adapted a tried and tested dismantling methodology to enable the sequence to be carried out within the limited working area and carried out alternative processing methods to ensure vibration and hot work fumes were kept to an absolute minimum. Despite the challenges of the project, the O’Brien SCS site completed the dismantling of each dockside crane in only one working day, meaning the entire project was delivered ahead of schedule, with zero health, safety or environmental incidents, to the delight of the HPC Terminal operators and the Bristol Port Company.