Serving the world-wide oil and gas industry, Dunlop Oil & Marine produce specialist hoses for demanding applications for every stage of oil and gas field development. New overhead process cranes from Street Crane Company have been installed to meet the unique process requirements. These cranes have been specially engineered to fit the existing structure which presented a limited height envelope.
Overhead cranes play a crucial role in efficiently manufacturing hoses of different construction, easily switching production from one hose type to another in response to the varying and urgent demands of Dunlop’s global oil and gas customers. Hoses are formed on long mandrels of a defined diameter around which the hose is built using resins and reinforcement in a specified pattern. Cranes are needed to load the mandrels onto the hose fabrication machines and to offload the completed product for transportation down the workshop for testing.
In the main production area Street have provided two triple-girder cranes of 9.6 tonnes, with a 3.2 tonne hoist on each beam to support the long hose lengths. These cranes may be operated singly or electronically synchronised to move together when double length hoses are produced.
“There were significant technical challenges,” explained Chris Lindley-Smith, Street’s sales and marketing director. “The main area has effectively six single girder cranes but configured as two triple girder cranes by the use of rigid link beams. The limited height envelope caused a complication in that a conventional crane, spanning over 18 metres, would be too deep a beam to be accommodated. To enable a crane beam of lower depth to be installed, the main beam comprises two section of 9.144 metres with a mid-bay runway providing support in addition to the usual side runways. Taking account of limited height available, Street’s ZX 64 LH – low headroom hoists are deployed. These straddle the main beam and run on the lower flange of the beam to minimise intrusion of the hoist into the space below the beam.”
In a second workshop, where heavy duty and higher diameter hoses of shorter length are produced, a double girder crane of 15 tonnes safe working load is installed. This was installed at a time of transition from one type of hose manufacture to another. In the first phase of use, the crane was fitted with triple hoists providing lift capacities of six, three and six tonnes. This allowed the bulk of the hose weight to be taken by the six tonne end hoists with the smaller hoist in the centre preventing sagging. Subsequently, a more rigid hose has been made in this area and so the crane has been re-engineered with twin hoists of 7.5 tonnes taking the whole hose weight. In the test and warehousing area a double girder crane of 20 tonnes, with twin 10 tonne hoists, is installed for cable and drum handling.
Street Crane’s ZX hoist technology is used throughout. The ZX hoist is built for endurance and low life-time cost of ownership in the world’s most advanced hoist manufacturing facility. Based on an open chassis, components run cooler and are easy to access for service. The hoists include unique safety features such as the easily accessible brake, working directly on the primary gear shaft and located away from the motor to avoid heat transfer. Gears, which run in an oil filled gear box, are easily inspected via an access plate without the need to dismantle. Digital load displays, audible approach alarms, anti-collision protection and HBC radio controls ensure safe and reliable crane operation throughout the plant.
Chris Lindley-Smith noted, “Cranes are often an integral part of the manufacturing process, but Dunlop Oil & Marine have taken this process crane integration one stage further. These cranes have been engineered to enable both tooling and product to be handled safely, efficiently and flexibly, helping the company achieve greater responsiveness in their manufacturing operations.”