During the recent renovation of the old Trollhätte Canal, Brokk successfully launched its new attachment coupler enabling tools to be interchanged entirely from the operator’s remote control box. This time-saving new feature of Brokk demolition machines is a major advantage when attachments must be switched often or when the change for various reasons must be remote-controlled.
Sidewalls demolished with Brokk
Demolition contractor Betong Borrspecialisten was chosen to renovate the 85-year old locks of the canal which runs from the Vänern lake to the Kattegat strait between Sweden and Denmark. Using electric remote-controlled demolition machines from Brokk AB in Sweden old concrete reinforcements in the sidewalls of the locks were cut away to be replaced with new lining. The contractor used one Brokk 180 and one Brokk 330 for the demolition.
There was very little space between the edge of the canal and the bollards, and at low water when the gates were open there was a fall of 9 metres (30 ft) from the edge down to the water. Needless to say, the operator appreciated the possibility to step back and control the machines remotely from a safe place. The smaller Brokk 180 was used on locks where the space was most restricted and with its space requirement of only 800 mm (31 in) in width, it just went between the row of bollards and the outer edge. The adjustable outriggers ensured the machine was stable even where it was confined and uneven.
Demolition started with two longitudinal cuts sawn into the wall to give a tidy edge. Brokk then cut away at the concrete, cleaning away the rubble and loading it into a special container ready for transporting away. Cutting and loading had to be carried out metre by metre due to the tight space. The work was made a lot easier thanks to the arm on the Brokk 180 being fitted with a device that enabled the tools to be connected both mechanically and hydraulically from the operator’s control box. The operator could quickly and easily switch between the breaker he used for tearing off the concrete and the bucket, digging up and loading out the rubble. "The new attachment system has worked perfectly", Peter Börjesson from Betong Borrspecialisten confirms. "For this job, when I was changing tools almost every 5-10 minutes, it has saved a lot of time and also made it much more comfortable for the operator".
"Brokk's hydraulic attachment system has been developed to make the Brokk machine even more efficient when using different tools", says head designer at Brokk AB, Anders Norberg. "The advantage of the system is particularly obvious when the job calls for frequent tool changes or when switching tools must be done remotely, for example in nuclear environments. The system also means a higher level of safety for the operator." The new attachment device can be adapted to suit all types of tool that can be used with the machine.
Manoeuvring the arm from the remote control box, the operator picks up the attachment and connects it both mechanically and hydraulically from the control box by a combined switch and lever operation.
In relation to their small and compact size, Brokk demolition machines have a unique capacity. The medium-sized Brokk 180 has a reach of 4.5 metres (14ft 9in) as standard (just over 5 metres (16ft 9in) with the optional telescopic arm) and can operate with a hydraulic breaker delivering 410 joules of power (600 foot-pound). Buckets for the machine are available in varying widths with volumes up to 80 litres (2.8 cu.ft). Brokk 330, the largest and strongest model in the product family, works quickly and efficiently with tools weighing up to 550 kg (1210 lb) and has an arm that can reach about 7 metres (23 ft). The caterpillar tracks and the foldable outriggers ensure great accessibility and a stable and safe working position.
The canal
The first waterway between the Vänern lake and the Kattegat strait was ready in the year 1800 but the present Trollhätte Canal was inaugurated in 1916. The six locks, designed to handle a total difference in water level of 44 metres (144 ft), were taken into service that very year. The renovation of the locks started in the spring of 2002 and for a couple of weeks in the autumn, the canal was closed to traffic while the lock gates were replaced. The newly renovated, 82-kilometre (50 miles) long canal was then reopened in September to allow the passage of the around 2,600 merchant ships and 3,000 leisure boats that use the busy canal every year.
Betong Borrspecialisten in Lilla Edet started operations in 1989 with concrete drilling. In 1992, the company purchased its first Brokk demolition robot and was able to expand its scope of activities. By and by more Brokk machines of various sizes were added to the fleet and in 2001 the brand new model Brokk 180 was acquired. Betong Borrspecialisten currently employs two people.