A system of compact and powerful high-pressure (700 bar) Enerpac RR series hydraulic cylinders operating upside down has been used successfully to position large condensate storage tanks for Eni Australia on the Northern Territory coast.
The system, incorporating 10 of the rugged RR 1006 cylinders, was employed on 180 ton tanks manufactured in Perth then barged up the coast and finally trucked to the remote area where they will hold liquid condensate piped from the Blacktip gas field in the Joseph Bonaparte Gulf, about 245 km southwest of Darwin.
Erection of the condensate tanks is being undertaken by Monadelphous, a leading national engineering group, near the Northern Territory’s Wadeye community between Darwin and Wyndham.
The Enerpac hydraulic cylinders (357 mm high with a 168 mm stroke ) were supplied to Monadelphous by Winnellie Hydraulics, Darwin, who developed and tested the system prior to delivery.
“We had to design the cylinders for a lowering not a jacking job, to allow a controlled descent of the storage tanks into position,” said Winnellie Hydraulics’ Richard Nicholson said.
The system had to be safe, reliable and serviceable, because of the remote area in which it was deployed.
After being manufactured in Perth and barged up the coast, the tanks were offloaded at a purpose-built wharf onto multi-wheeled low loader transporters that drove onto the barges.
The transporters slid their trailers beneath the tanks, jacked up the trailers and hauled the tanks on a two kilometre journey from the wharf to the storage site.
On arrival, the trailers lowered the condensate tanks onto blocks before driving away.
The weight of the tanks was then taken up by Enerpac hydraulic cylinders supported on another set of blocks.
Ten 100-ton Enerpac RR-1006 double-acting hydraulic cylinders were used through AM41 and AM21 valving to safely lower each large tank into its final position.
The cylinders were powered by a ZE5420SW 415 V electric pump with a 20 litre reservoir and a remote control.
The Enerpac cylinders were mounted upside down on the underside of the tank so that, as the blocks were progressively removed, the jacks didn’t have to be re-seated.
Eventually the cylinders were lowered into a recess in the concrete that allowed them to be cut off the tank bottom and removed.
Lowering and positioning the tanks was a gradual process that was spread over two working days.
Other similar lowering jobs are planned by Monadelphous for 2009, including the positioning of 350 tonne equipment modules on the Wadeye site.
Enerpac’s RR-Series of double-acting cylinders have capacities ranging from 10 tons (101 kN) to 520 tons (5108 kN).
The 100 ton RR-1006 model used on the Wadeye site has a stroke of 168 mm, a collapsed height of 357 mm and a cylinder effective area of 133.3 square cm when pushing.
For heavy lifting in remote locations, the RR-Series is typically powered by an Enerpac ZE-Series electric pump.
These pumps are ruggedly designed and built to stand up to harsh industrial environments.