Replacement Cylinder Manufacture for Commercial Linkspan
A busy harbour based in the South of England, recently requested that Apex Hydraulics manufacture a new hydraulic cylinder for one of their linkspans.
Linkspans are hydraulically operated steel roads that extend from the edge of a harbour out to a ferry. They are usually highly specific to the type of ferry and cargo that is to dock at that berth, as well as the immediate environment, including the tides. The linkspan is often made with a particular ship in mind, as part of a long-term contract. Other berths may not be high enough, low enough or deep enough to accommodate that ferry. Linkspans for goods ferries are typically far larger and heavier than those for passenger ferries, in order to be able to accommodate HGVs.
These berths are important business for harbours. For example, a port may have a 15-year contract with a ferry company transporting goods from France or Spain, docking always in the same berth that was built to suit that ferry. This linkspan is vitally important, because if it stops functioning the ferry will no longer be able to dock and the entire contract may be voided, with the ferry operator finding a different harbour further along the coast and the harbour losing out on a large financial contract.
A time critical turnaround
The customer noticed that there was some rusting and corrosion to one of the hydraulic cylinder rods on the link span. This is not a risk in terms of danger to life, but a situation that, if left, can cause eventual failure of the system and the linkspan to no longer work. With no spare cylinder to swap in, the customer requested that Apex build a new cylinder.
While the job was not required immediately, it was extremely important that once the cylinder was removed, a new one could replace it almost immediately.
Usually when a cylinder is on the verge of failing, Apex will do a strip and assessment and repair the original cylinder, as this is the most cost-effective method. Almost all cylinders can be repaired, so it is not necessary for them to be discarded and replaced. In a normal situation, the cylinder would be removed and transported to the Apex workshop in Dewsbury, where it would be stripped down to its component parts and repaired. However, this process can take some time, and in this case, it was critical that there be as little downtime as possible, so it was decided that a new cylinder be manufactured.
The Apex response
The hydraulic cylinder was 35 years old and there were no original drawings to work from. Therefore, an Apex engineer went to the harbour to take measurements and create a new drawing. These drawings were used to manufacture a new replacement cylinder while the original was still operational.
This new cylinder is due to replace the problematic cylinder this Autumn. This switch will take a matter of hours and can be achieved over the space of a weekend, rather than the weeks that would have been required to make a replacement from the old one. After the replacement has been made, the problematic cylinder will be brought back to Apex, for the routine strip and assessment so it can be returned in As New condition and the company can then have a spare cylinder for future use, without a long lead time.
Top quality manufacture
The new cylinder was made to high specification offshore construction, with a 17-4PH piston rod with 50-micron hard chrome plating to ensure resistance against pitting and cracking and keep the new cylinder functioning for as long as possible, even with the wind and salt that is expected in a sea environment. All Apex Cylinders are thoroughly inspected and tested prior to being shipped out for fitting and are all manufactured bespoke every time, meaning that customers can always expect a durable, top-quality cylinder to exactly meet their requirements.
The following products were utilised as part of this project. For more detailed information on these products, click on an image below…