Product category:
Specialist and bespoke handling equipment and services
News Release from: Enerpac | Subject: PLC-controlled synchronous lifting system at BAE
Edited by the Manufacturingtalk Editorial
Team on 14 February 2008
System weighs and manipulates large
fabrications
A PLC-controlled synchronous lifting system ensures that the desired load paths of large, pre-fabricated sections into the ship's hull structure are maintained during transport.
BAE Sysems' Surface Fleet Solutions' Govan and Scotstoun shipyards in Glasgow, UK, are assembling, launching and fitting out six Daring Class Type 45 anti-air warfare destroyers for the UK's Royal Navy The bow sections, masts and funnels for all six ships are being built in Portsmouth
This article was originally published on Manufacturingtalk on 29 Aug 2002 at 8.00am (UK)
Related stories
Hydraulically clamp workpieces without pressure!
A novel combination of hydraulic and mechanical clamping retains clamping force so workpieces, awaiting machining, may be clamped onto the fixture well in advance of when they are required.
Time to take a look at hydraulic clamping?
Hydraulic clamping of components for machining on conventional or pallet type machining centres ensure consistent clamping forces and reduce downtime.
These destroyers will have an overall length of 152.4m, space for a crew of 235, a displacement of 7350 tonnes, a top speed greater than 27 knots and its range greater than 7000 nautical miles.
The first one is HMS Daring and is to enter service in May 2009.
The ship's hull is manufactured in sections or 'blocks' in a fabrication shop adjacent to the berth and slipway.
Further reading
Digital gauge makes precise pressure measurments
An addition to a broad high pressure hydraulic line is digital gauge that offers high quality and precise pressure measurement in a flexible compact package.
High tonnage cylinders move heavy loads
A new range of single and double acting high tonnage hydraulic cylinders offer lifting capacities of 50 to 1000 tons.
Using air to drive hydraulics
Compressed air of 6 to 7 bar can be used to drive a small air motor to generate hydraulic pressure up to 700 bar.
Five blocks are moved in total to build one ship.
The heaviest block weighs over 1400 tons.
* Hydraulic lifting and load transfer - multi-wheeled transportation vehicles transport each block to the slipway and aligns it longitudinally to the slipway.
During this procedure the slide-tracks on the slipway are removed so that the vehicles can drive the blocks into position.
The Enerpac Synchronous Lifting System is then used to lift the block free from the transport so that they can be driven away.
During the lifting procedure the 16 points PLC-controlled synchronous lifting system operates within strict load and stroke constraints to ensure that the desired load paths into the ship's hull structure are maintained.
With the transport removed and the hull segments supported by the hydraulic system, the blocks are weighed with the synchronous lifting system to confirm the design calculations.
* Slide-track installation, lowering and block manipulation - the next step is the slide-track installation.
The slide-tracks on the berth's slipway can then be re-installed.
The block is lowered synchronously and the load is transferred on to the slide-tracks.
The hydraulic lifting system permits the manipulation of the blocks prior to welding to the adjoining section.
This manipulation - lifting, lowering and rotation, is a PLC-controlled hydraulic movement.
* Hydraulic system integration - in the use of hydraulics in heavy lifting projects, application knowledge and expertise are very important, said Enerpac to manufacturingtalk.com.
Accurate lifting, lowering, pushing or weighing has a significant effect on structures.
Very accurate manual control and monitoring is complex and very time consuming.
And more - accuracy is more important than speed - the advantage of PLC controlled integrated hydraulic systems is enormous.
Every step of the lifting process can be monitored via the display of the PLC control unit.
Apart from the very accurate and stress-free movement of steel structures, concrete segments, etc.
Enerpac provides a safe, easy to manage, cost- and laboursaving solution.
The Type 45's weight must be optimised and consequently the hull skin is relatively thin when compared with a commercial ship.
Therefore, when lifting and lowering, the load paths must be strictly controlled and this would be almost impossible with manually controlled systems, said Enerpac.
Controlled hydraulic movement brings safety to the structure.
The second advantage is the increase of productivity where hundreds of man hours were saved against traditionally controlled lifting methods.
Moreover, this versatile lifting system is employed on various other lifting and weighing operations around the shipyard.
Enerpac hydraulic system integration, of high force hydraulics and advanced control technology, nowadays play an important role in the controlled movement of large-scale engineering projects, like the launching of the French Millau Viaduct, and lifting and weighing of these heavy ship's hull segments.
• Enerpac: contact details and other news
• Email this article to a colleague
• Register for the free Manufacturingtalk email newsletter
• Manufacturingtalk Home Page
Search the Pro-Talk network of sites
