Semco has supplied newmini excavators for use on the Sydney urban rail network. The equipment includes three hi-rail and two conventional excavators; fitting of special equipment for safety functions and maintenance
Hydrostatic hi-rail a benefit
The authority had originally specified a static hi-rail system. On further inspection and assessment of the proposed alternative self-propelled hydrostatic hi-rail, it was decided a hydrostatic system would be the best solution as static hi-rail guidance system would have limited the excavator’s speed to just five kilometres per hour.
The hydrostatic system enables the Takeuchi TB 250 excavators to travel on rail at up to 15 kilometres per hour in either direction – a major advantage for faster completion of work.
Traveling at this speed means that large distances can be covered more efficiently. This is a real advantage on track sites in tunnels or other areas presenting limited access.
Need for fully rail safety compliance
For full safety compliance, the customer opted for the highest safety control available. These included work zone, working radius and height being selectively managed and limited. Semco says its system on the Takeuchi TB 250 excavators are functional as well as being fail-safe, claiming the jobsite supervisor has complete control over what level of latitude the operator is permitted.
The worksite supervisor may elect to engage, for instance, the height limiting system. Once the supervisor engages the height limiter, he removes the dedicated key that controls that function.
The operator has no means to overrule the supervisor’s judgment.With the safe work zone limiters, the operator is compelled to comply with the supervisor’s instructions. Furthermore, the work zone limiter is designed so that when the machine is placed on the railway lines, the operator can work within a prescribed arc, and therefore has no possibility of accidentally swinging the implement, bucket or attachment around and contacting a train coming from the opposite direction. The Radius Limiter works in a similar way
HyRail expertise is critical
The TB250 excavators are the first that Semco have supplied with the Swedish built Rosenqvist Hyrail system.