Modifiering av grävmaskin för schakt- och gruvdrift

Remote Control Bobcat excavator earns its stripes in Shaft Work in Sweden

The articulated boom allows the machine to fit in the shaft, it can be remote controlled to manoeuvre it into a better position if needed

A new Bobcat E88 8.9 tonne mini-excavator has been specially modified in Sweden with a number of features including remote control, for work on building ventilation shafts for the Förbifart Stockholm (Stockholm Bypass) road tunnel project in Stockholm.

Being carried out by main contractor, AF Gruppen, the Stockholm Bypass project is one of Sweden’s largest infrastructure projects, to create a series of underground motorway tunnels between the Kungens Kurva interchange in the south of Stockholm and the Häggvik interchange north of Stockholm. Most of this bypass, more than 17 out of 21 kilometres, is being built underground.

The bypass will become the world’s third longest road tunnel in the proximity of a city, after the Westconnex Tunnel in Sydney and the Yamate Tunnel in Tokyo. 140,000 vehicles per day are expected to use the bypass.

The Bobcat E88 in Stockholm was originally adapted to meet the special regulations of underground works in the mining region in Kiruna in the north of Sweden. The Bobcat E88 was adapted and supplied by Luleå-based Nordkust Maskin AB, the company responsible for sales and service of the entire Bobcat range in the area from Umeå to Kiruna in northern Sweden. This is in collaboration with Bobcat Sverige AB, the main Authorised Bobcat Dealer for Sweden, with its head office in Kristianstad.

The close proximity of Nordkust Maskin AB was another reason for the choice of the Bobcat E88 excavator, as the company is ideally placed to provide service and support for work in Kiruna. Nordkust Maskin AB managed this project in close collaboration with Bobcat Sverige AB and Bobcat Company and as a result was able to deliver the heavily modified E88 excavator on time for the customer, Bergteamet AB, a specialist shaft and tunnel contractor, based in Boliden in Sweden. Nordkust Maskin is working on another E88 adapted for the mining industry that will also be used for a drilling application.

Founded in 1999, Bergteamet AB brings with it almost a century of mining tradition in northern Sweden. The company developed quickly from offering support services to the local mining industry, to go on to complete major projects both in Sweden and abroad. Today, Bergteamet AB offers a wide scope of expertise and know-how from numerous projects and in a very wide range of geological conditions.

As part of the modifications needed on the E88, it was decided that the ability to remote control the excavator was needed to increase the safety of both the work and the environment. The excavator also needed to be modified to protect it for working in the very harsh environment of the underground vertical shafts.

Bergteamet has been using the Bobcat E88 to sink ventilation shafts for the Stockholm Bypass project. One of the first was at Lovön at Drottningholm outside Stockholm. The process used to construct the shafts begins with making a circular hole at ground level using blasting and hauling the material away.

The next step is to lift the E88 into place in the hole created at the top of the shaft, where the articulated boom allows the machine to fit in the shaft, from where, it can be remote controlled to manoeuvre it into a better position if needed. This includes the use of on-board cameras again driven from a control room, away from any hazardous areas. The E88 is equipped with a tiltrotator allowing it to be used with a breaker to remove loose material as well as an attachment for rock scaling work. It also has water connections for dust control.

Other attachments/features on the modified E88 include:

• Åkerströms Radio Control
• ABL Buckets
• Hammerglass explosion proof windows
• Lincoln Lubrication
• Forrex automatic fire extinguisher

The E88 delivers outstanding performance from a compact dimension machine and excellent stability with high digging output. The proven Bobcat D24 Stage V 4-cylinder engine offers a maximum power output of 48.5 kW (65 HP) and ensures the highest performance and maximum reliability.

The high breakout forces and fast cycle times in the E88 continue to be an essential part of Bobcat’s DNA. Like all R2-Series machines, the E88 is designed to achieve superior 360-degree stability in any situation, even when digging over the side or when handling heavier loads. It is a well-balanced machine for operating with different attachments owing to improved weight distribution, extended track length, optimized counterweight design and dual flange rollers guaranteeing superb over the side stability. This assures operators of confidence in any situation, even without the optional add-on counterweight.

The new R2-Series E88 is designed as a balanced machine in performance, compactness and stability. The rear overhang is only 327 mm (without an add-on counterweight), allowing this 8.9 tonne machine to be used in confined space areas. The dynamic and robust design reduces the risk of downtime, with the heavy-duty steel side channels and the counterweight acting as a bumper to protect essential components, as well as all the hoses, pipes, valves, lights and other sensitive components that are important for excavator functions.

The R2-Series machine concept uses proven, reliable components (such as the engine, joysticks, cab etc) and if maintenance or service is needed, wide opening covers allowing access to all maintenance points from the ground level mean this can be done easily on the job site.

By STEPHEN WHITE
-MARCH 26, 2024