Selby Swing Bridge – a group effort

28 April, 2016

Closing down a road in the heart of the North Yorkshire town meant the team had to work fast and smart within an incredibly tight timeframe. Branch Hydraulic Systems managed the whole project, assisting with the road closure and maintaining efficient health and safety standards throughout.

The strict time constraints on this job meant the task had to be completed within four days from start to finish. Branch Hydraulic Systems allowed the bridge to be managed and kept open to pedestrians who took an interested and positive view on the project. The project included the following works:

• Design, manufacture, installation and commissioning of a new high specification hydraulic power unit.

• A new PLC (Programmable Logic Controller) installation.

• A new large planetary gearbox.

• Upgraded lubrication system – this was converted from a manual system to an automated PLC controlled setup including new feeder blocks and pipes.

• New hoses.

• And mini refurb where required i.e. manual winch system, prepare and paint of the drive box.

• Chain service, clean, tension and lubrication.

This large job involved collaboration between the different divisions of Branch Hydraulic Systems’ parent company Group HES, combining their technical expertise across the application.

The project involved removing the old severely corroded hydraulic power unit, which was unserviceable and installing a brand new unit, that is both innovative and long-lasting.

The HPU is critical to the operation of the bridge, operating the jacking mechanism required to flex the bridge and free it of the abutments and also to operate the locking nose bolt, without which the operation would not function. The new HPU makes maintenance easy because Branch Hydraulics understand the importance of maintaining machines to extend service life and reduce machine downtime.

The PLC system also needed to be upgraded- the key control intelligence tool for operating the bridge; without this system, it cannot function in an automated operation. The new PLC system brings the technology up to date and complements the new HPU system. The main benefit, apart from having a modern, reliable control system, is that the PLC controls could be replaced in the same outage as when the new power unit was installed.

Pre-assembly

The general design of the unit was built with the harsh environment in mind, it was manufactured with corrosive resistant parts and stainless steel where required. The system was pre-assembled at the factory and tested as a complete hydraulic unit to satisfy the factory acceptance tests, using our latest video technology to record the findings. The reservoir, filtration, motor pump sets and valves were mounted to the skid. The motor pump set consists of a Moog radial piston pump close coupled to the electric motor with rigid bell housing and flexible drive coupling. The motor had an IP56 upgrade reducing the risk of moisture ingress to the electrical windings. A Moog pump was selected due to its proven track record for reliability and robust design.

Flow from the pump is passed through a pressure line filter with clogging indicator and then to a manifold assembly. Mounted on this manifold were the solenoid valves, relief valve, pilot operated check valves and some of the flow control valves. Duplomatic valves were selected as they offer a corrosion resistant zinc nickel finish as an option on some of their valves. A second, smaller, manifold, with the same material specifications was also mounted to the skid complete with dual flow control valves on it.

HES Tractec, another division of Group HES, also provided their expertise to the project – the specialist engineers built and installed the large Comer planetary gearbox and 90 degree drive transfer adapter, which rotate the bridge.

There aren’t many companies out there that have all the different skill set and expertise, required to complete such a complex job. This project is just one example of how Group HES uses their depth and breadth of service to provide unique engineering solutions under one contract.

High regarded

The group manager Simon Dickinson was delighted at the full turnkey effort and in his words: “The value of having a company to manage and carry out a multidiscipline project like this from start to finish is highly regarded. Our work ethic is to understand the customers’ needs and deliver the quality we illustrate and promise. The effort was fantastic but not at all surprising…great result.”

http://bhs.grouphes.com