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Graham Liddell, of GT Liddell Contracting, gave a presentation at the crane conference about his niche company and specialised equipment developed to work in the rail corridor.
With its experience working as a subcontractor welding bridges, GT Liddell Contracting was approached by the railways about working on its bridges. Graham saw that specialised equipment would be needed to access the remote locations where railway bridges are often found, and that’s when he sat down and started designing construction equipment that could run on rails. The company now boasts its own mechanical and civil engineers, as well as draftsmen, and a full engineering workshop that is able to manufacture and maintain its specialised equipment. Vehicles modified to be able to run on railway tracks as well as roads are referred to as hi rail vehicles. Among the hi rail gear Liddell Contracting has designed are cranes, diggers, pick and carry trucks, tipper trucks and concrete trucks.
The hi rail equipment is designed to comply with KiwiRail’s rules and regulations. One such rule limits the size of the machine to less than 20 tonnes, as any piece of equipment on the rails over this weight can only be operated by a fully-fledged locomotive driver, says Graham. When working on a new hi rail vehicle, the designs are submitted to KiwiRail’s mechanical engineers for review and approval. An operator’s manual, with emergency recovery systems and health and safety requirements, is also developed. The design must also be submitted to a transport engineer for LTSA approval and to receive LT400 certification. Once the paperwork is cleared, Liddell Contracting begins to transform the vehicle into hi rail.
Next, together with KiwiRail engineers, Liddell Contracting conducts on-track tests of the new hi rail vehicle – it must be able to stop within 30 metres at 50kph. They also run panic stop tests, rail stability and chassis twist tests (to make sure its not going to fall of the tracks when going around corners), back to back rail gauge tests, visibility of vehicle on rail test, and a check that the horn (standard horn is replaced with an air horns) is audible at the correct decibel level. Hi rail vehicles require more licences than usual – it needs yearly registration with LTSA, yearly LOCO registration with KiwiRail, six monthly LTSA COF inspections, six monthly CO115 inspections by KiwiRail and, for cranes, a yearly crane certificate. Naturally, Liddell Contracting is also required to train its drivers to drive on the rails. Liddell Contracting is based in Greymouth, but works throughout the country – for the last five years it has been working on the Midland Line, where the coal trains give the rails a good work out, and also as far north as Auckland and Cambridge.
The company has done a lot of formation work for culverts which led it into the culvert market and it now precast culverts and ballast deck bridges. As well as its specialised hi rail gear, the Liddell Contracting also employs support cranes up to 100 tonnes to work on the rail, as well as other access equipment. GT Liddell Contracting currently has a staff of 57, and as well as its hi rail division, works in the mining, cement and dairy industries.
Contractor Vol.34 No.7 August 2010 |
Graham Liddell started his career back in 1974 as a contract welder, and GT Liddell Contracting quickly grew with the demand for its services. One of the company’s bigger projects, the Otira Viaduct in 1977-78, saw staff numbers shoot up from just five to 25.
The chief advantage of the hi rail equipment is that it can access any part of the railway, regardless of how remote or how rugged the area is, without having to build access roads – this makes any project more affordable and it can begin sooner. Another key advantage is the ability for hi rail gear to work in restricted spaces – such as on a narrow viaduct, high above a steep gorge.
Once complete, the machine is inspected by a transport engineer who approves the modifications, then the vehicle resits its Certificate of Fitness. KiwiRail also inspects and approves the hi rail vehicle.
Usually, the company is brought in for jobs with difficult access – strengthening viaducts in remote gorges, undertaking bridge repairs and doing rail formation work.