HomeAdvertising featureGripple Swiftline Rail Dropper - The product shaking up UK rail electrification

Gripple Swiftline Rail Dropper – The product shaking up UK rail electrification

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The commitment made in the UK Government’s Decarbonising Transport Plan for an ambitious programme of railway electrification is both complex and challenging. With progress sat at just over a third of the 13,000km of track in Great Britain’s rail network electrified, the rollout required is extensive. To achieve its targets, Network Rail has called on suppliers for support – challenging the status quo and developing innovative solutions to promote efficient, effective, and safe electrification projects.

One such innovation is the SwiftLine Rail Dropper from Gripple. Recently approved by Network Rail and the Federal Office of Transport (FOT) in Switzerland, this new dropper changes the game for overhead line equipment (OLE) maintenance and repair, helping contractors maximise possession windows and complete faster and safer dropper installations.


Maintenance, repair, and improvement work to OLE is one of the most challenging aspects of any electrification project. Having the right solutions on hand is essential to ensuring work can be completed safely and efficiently. Hanging vertically to connect the catenary and contact wires at regular intervals, OLE droppers are an essential component of electrified railways, providing support and conductivity to both wires and ensuring long-lasting stability across the network.

Credit: Gripple

The challenge with rail droppers arises with installation. According to research undertaken by the University of Sheffield as part of the UK Rail Research and Innovation Network (UKRRIN), installing rail droppers is one of the most time-consuming aspects of an OLE project. It is one of the reasons highlighted for the slow rollout of electrification. With OLE possession windows already placing extreme time pressure on engineers, the need for a faster, easier-to-install rail dropper is paramount. 

Familiar to the rail industry, with its ground-anchoring systems used for embankment stabilisation, Gripple saw this as an opportunity. Applying the same technology it already applies to catenary suspension in other markets, Gripple identified similarities between the problems OLE installers were facing and those it was already solving in the building services sector. Taking a collaborative approach to innovation, Gripple engineers took on board the feedback from contractors and other industry stakeholders, understanding the challenges they face and solving them. The result is a game-changing solution – faster, safer, and easier to install than any other dropper on the market and set to make a massive difference to electrification projects up and down the country.

Addressing challenges 

Gripple prides itself on being a problem-solver. On designing products that tackle the real on-site challenges facing contractors every day. Its SwiftLine Rail Dropper is no different. As with many major infrastructure projects, the biggest challenge facing OLE engineers is time. Possession windows are never long enough, and with large fines facing firms that exceed the allocated time for maintenance and repair, it’s in everyone’s interest to install efficiently.

Conventionally, OLE droppers are supplied as a kit and need to be cut to length and assembled on-site. This is extremely time consuming with great care and attention required to ensure the correct and accurate installation.

Designed to be quicker, safer, and easier to install, Gripple’s SwiftLine Rail Dropper comes pre-cut and pre-assembled, giving contractors a ‘plug and play’ solution straight out of the box. This completely removes the need to cut, crimp, and fix on-site, saving installers hours on assembly times and significantly reducing the likelihood of human error.

Available in a choice of pre-cut lengths, the Gripple SwiftLine Rail Dropper offers infinite height adjustability meaning one dropper can meet a variety of drop lengths. This saves time on specification and installation and vastly reduces the risk of waste if the drop length is measured incorrectly. The pre-assembled design also allows for tool-free installation with minimal training, making projects simpler and safer, limiting the time engineers spend working at height and in the dark. 

Similar challenges occur with the contact clamp torque. Installed and set manually using hand tools, often in the dark, at height, and under significant time pressure, setting the correct torque is susceptible to user error. Exposing projects to high replacement costs or delays to ensure accurate installation. To address this, the SwiftLine Rail Dropper features an innovative Auto-Torque contact clamp, using a pre-set lever clamp to provide a set clamping force, guaranteeing ‘right-first-time’ installation and the correct torque every time.

Improving the speed of installation while ensuring a fully conductive product, the SwiftLine Rail Dropper utilises Gripple’s unique Volt Lock System. Housed within the catenary wire top dropper and including a roller which both grips the dropper wire and ensures constant contact with the copper housing of the product, this unique feature makes the product fully conductive at all times and allows for greater adjustability and speed of installation when fixing to the contact wire.

Quality and testing

While the demand for innovation in the rail sector has never been greater, it must be approached with care. Products used in UK rail infrastructure must first be subject to Network Rail approval, providing assurances that products are fit for purpose, safe and reliable, and do not pose risks to the railways.

Credit: Gripple

The Gripple SwiftLine Rail Dropper went through an unprecedented level of testing to ensure it would exceed the requirements of Network Rail and the BS EN 50119 standards, evidencing its unrivalled durability and reliability.

In the pursuit of further input from industry stakeholders, Gripple has continued to engage key players to test the SwiftLine Rail Dropper. This includes recent installations on the Sandwell and Dudley Line between Wolverhampton and Birmingham. The feedback has been outstanding, with engineers citing the ease and speed of installation and the height adjustability as critical benefits when working within tight possession windows.  

Manufactured in the UK with complete transparency in environmental testing and product traceability, Gripple SwiftLine Rail Dropper offers OLE engineers and contractors the highest quality and most sustainable OLE dropper on the market. Boasting its own sustainability credentials, which includes carbon-neutral UK operations and vertical integration, Gripple is supporting the net-zero agenda, helping to provide transparency and continuity to its customers.

To help launch the product to market in the UK, Gripple has partnered with established rail supply chain experts Unipart Rail with the aim of making the SwiftLine Rail Dropper as accessible as possible to the market.


With no less than nine unique product features and the result of two years of robust testing and development, the Gripple SwiftLine Rail Dropper is an OLE dropper more advanced than anything else on the market. With installation times up to eight times faster than a traditional dropper, this product allows OLE engineers to take control of electrification projects, get more done in each possession window, and bring forward project completion dates. As the journey towards electrification continues, the Gripple SwiftLine Rail Dropper should be at the forefront of the transition and in the arsenal of OLE engineers up and down the UK rail network.

Lead image credit: Gripple

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