|
|
| |
 |
|
| EarthMovers |
|
| Working over water – Editor Graham Black visits Land & Water Plant, which knows a thing or two about long-reach excavators working over water |
With 30 long reach excavators over 13 tonnes and a number of road-transportable pontoons, Land & Water Plant is the major player in this specialised sector of the plant hire market. Not only in the UK and Ireland, but also as far a field as the Caribbean and Azerbaijan, they have been involved in some of the most unusual muck-shifting contracts imaginable.
The Land & Water Group traces its origins back to 1972, when Richard Melhuish and Malcolm Hindley-Jones formed a business to specialise in working in the difficult ground conditions that are often found close to water - operating the very earliest low ground pressure Long Reach Hymac Excavators. Tragically, Malcolm died at the very young age and Richard continued the business on his own until, in 1989, he met plant hirer James Maclean and the two men joined forces as MHJ - Land & Water Ltd.
Their big break came in 1993, when Richard and James learned that British Waterways were about to embark on a major programme of canal restoration. They teamed up for a period with Simon Mowat of Inland Dredging, who operated Watermaster floating dredgers. Together they formed a joint venture company named Land & Water Services, secured major canal contracts and the rest, as they say, is history.
Today, the Land & Water Group has four main businesses; waterside property development, a remediation company dealing with contaminated material, a contracting organisation and a plant hire company.
Richard Maclean is a director of Land & Water Plant, the plant hire company within the group and has many years experience as a machine operator. His views on how to run such an operation is refreshing to hear, but first we visit one of their machines working just outside London, to get a better feel for the types of job they get involved with.
The 88-tonne Hitachi EX800H was bought specifically for its current job and fitted with a Land & Water designed 25-metre boom and dipper for a two-year contract to stockpile sand and gravel at Home Farm Quarry near Shepperton. Equipped with a 2 cubic metre bucket and an experienced operator, the machine is responsible for excavating over 400,000 tonnes a year.
In this case, the operator in question is Pete Brown, who has been working with the Land & Water Group for nearly 20 years. His opinion on the machine is simple and straightforward: “It’s brilliant”.
He is more forthcoming about the electronic dig system fitted to the big Hitachi, a Prolec Digmaster 3, with the optional valve cut out feature. Pete said, “The system wont let you dig any closer than a 1:1 slope, which is an important safety feature. The bucket position is shown on the screen in real time, so you can actually see what the bucket is doing underwater. This means that you are always digging to maximum efficiency.”
“The Prolec system also provides an accurate off-centre measurement, which may be zeroed at any point in the swing radius. This is perfect for digging underwater trenches, which is important for type of work that Land & Water gets involved in.”
In operation, the bucket that is depicted on the operator’s control screen mimics the crowd position of the actual bucket underwater, allowing full loads on every cycle.
On this type of job, is all too easy to excavate too close to the machine, undermining the solid working platform, which is required for this monster muck-shifter. The Digmaster is therefore programmed to prevent the bucket excavating below a 1:1 slope, which starts at 2 metres in front of the tracks.
As Pete approaches this limit, a green line appears below the bucket on his control box. The actual limit is shown by a red line on the screen and, no matter what, the system physically prevents excavation below this safe working envelope.
As an aside, there is a blue flashing light mounted on top of the cab, which is connected to the Prolec system and activated when it is in use. No blue flashing light means that the machine is working without this important safety feature switched on and the site management has a sense of humour failure.
One of the more unusual aspects about the Land & Water long reach fleet is that they design all the long reach equipment in house, with the help of a British university and then get it manufactured to CE specifications, using WELDOX high tensile steel.
Land & Water also has an unusual view on the buckets used for such applications, which are also designed in-house. No heavy-duty, massively reinforced structures for them. Rather it is a lightweight component to provide the maximum capacity at the end of the 25-metre boom and dipper, with a designed working life of just one year. Each end of the bucket pins are enclosed in end-caps, packed with grease for reduced maintenance.
There used to be a dragline working on site, but the new combination has provided the quarry operator with a ‘double whammy’ benefit. The excavator is able to dig into all the contours, making best use of the natural resource and this, in turn, provides more volume for the subsequent (inert) landfill operation.
When talking to Pete Brown and especially to Richard Maclean, one cannot help but get the feeling that this is no mere plant hire operation; it’s more akin to a contractor. Richard openly confirms this, both in relation to how the business works and the attitude of his operators. He says, “We provide expert advice as we are specialists in long reach and pontoons and this is our core business. We’re not just a plant hire business, but are able to provide guidance on both methods of operation and production rates.”
Anyone visiting his premises expecting to see a yard full of machines and workshops is in for a pleasant surprise. Located in a leafy country village outside of Guildford, Land & Water Plant has no traditional depot, but have a ‘virtual network’ across the UK, formed by trusted transport and maintenance companies.
Their fleet consists of JCB and Hitachi machines, together with a couple of Volvos. The average age of the machines is 24 months and no excavator is kept on the fleet for more than 4 years. In the summer months, most of the machines are deployed on external hire contracts, either as operated or non-operated machine. The larger machines tend to be all operated units, with detailed on and off hire inspections taking place on all non-operated equipment.
One of the things that really do seem to set them apart from other companies is their attitude towards operators, no doubt helped by Richard’s experiences early in his working life. He chooses only the best available, all of whom have CPCS cards, some of whom also have quarry safety passports and they only operate long reach machines.
All operators are provided with vehicles, personal protective equipment (including life jackets) and mobile phones. Richard personally visits each operator every 6 months for a formal appraisal and there is a bonus-driven machine maintenance and condition system in place. To top this off, in Richards words, “We do pay quite handsomely, with rates that reflect a notional 10-hour day if they are working away from home.”
Working over water presents some unique challenges to keep operators safe, particularly when they could be working in remote locations, and often alone. Land & Water deploy two unusual systems, the first is a man overboard system, which automatically send out text messages to three designated mobile phones if the lifejacket is immersed in water.
The second is a lone worker system, where a chest-mounted harness carries a buzzer, which periodically activates, requiring the operator to switch it off. If he doesn’t, emergency text messages are once again sent out.
Both these systems were developed by Land & Water to protect their workforce and will be available to hire to third parties later this year when new improved units are completed. The new devices will be linked to GPS location devices, particularly important if the job is on one side of a riverbank and the nearest bridge is miles away.
No visit to Land & Water would be complete without a work or two on their pontoons. These are unusual in so much as they are all road-transportable, allowing them to work anywhere along the canal or river network, the largest of which are capable of carrying up to 85 tonnes. When deployed, the excavator’s track motors are disconnected and the circuit is used to power the hydraulic raise and lower mechanism of the pontoon’s ‘spud legs’. When the operator is finished digging in one place, the legs are raised and the boom and dipper are used to push the pontoon back
Where a high degree of accuracy is required, real-time GPS systems are deployed. One such recent contract involved construction a 2km rowing facility in Caversham, where it was critical to ensure an even depth across the width and length of the course. A satellite ground station was deployed, linked to barges that surveyed the watercourse’s bed immediately in front of the pontoon-mounted excavator.
This information was continually sent to the dig control system in the excavator and displayed as dig or fill areas on the virtual chart. Where no fill was required, the material was loaded into an adjacent bottom-dump barge, which latter deposited the material in those areas that required substantial infill.
With the right combination of operators, experience, machinery and systems, Land & Water Plant is a force to be reckoned with when working near or over water. |
Back
|
|
 |
|
|
