Qatar success for Stelex

Two heavy-duty Hercules trommel screens manufactured by Stelex Construction are operating as part of a major port extension project at Rashaffan, on Qatar’s north-east coastline. The HT232s, the two largest Hercules trammels operating outside the UK, are being used to supply clean graded rock for the construction of a new harbour and breakwater.

Each trommel screen has a barrel diameter of 2.3m and is capable of accepting a feed rate of up to 1,000 tonnes/h.

The barrel is made up of two 4m long segments that are manufactured from high-grade steel bars welded and bolted together, while the apertures have been made to meet the customer’s individual requirement.

The barrel is supported on four steel rollers, two of which are driven by heavy-duty, variable-speed hydraulic motors requiring no drive chain or sprockets. The speed of the barrel varies but can be set to suit the type of material being fed to ensure optimum cleaning and grading at all times.

Material is fed into the trommel via a variable speed reciprocating plate feed table featuring hydraulic rams that adjust the required tonnage. The plate feed table is supported on rollers beneath the 160 tonne-capacity, wear-resistant Hardox feed hopper. 

Power for both the feeder and barrel is provided by a separate, remotely stationed electric/hydraulic power pack. As part of the contract, the Hercules trommel screens have been specified to operate in temperatures of up to 50°C, due to the hot and dry climate of the Middle East.

The equipment was designed, built and installed on site by Stelex within the scheduled time frame. When the port development is completed, the Hercules Trommels are expected to have processed over 30 million tonnes of rock for the construction of marine facilities and offshore barriers for the increasing shipping traffic using the Qatar port.

Stelex Construction Equipment Ltd, Prees Industrial Estate, Prees, Whitchurch, Shropshire SY13 2DJ; tel: (01948) 840840; fax: (01948) 841147.