Automated and Streamlined Production Processes
Manufacturing and supplying the Centrum Pile System in the UK since 1993.
Centrum Pile Ltd has Danish origins dating as far back as 1882. During the 1970’s Centrum Paele A/S was founded as an independent limited company with the primary purpose of manufacturing continuously reinforced precast concrete piles.
2008 saw the commencement of an investment programme in the UK facility exceeding £6.5million for the construction of our new, state of the art, bespoke production facility for the manufacture of continuously reinforced, concrete piles with a large portion of the process being fully automated. Since then further improvements in the production processes have been made to ensure that the manufacture of the Centrum Pile System maintains the high quality standards expected.
1. Robot Shed
The Robot Shed houses our two cage fabrication robots that have a combined capacity of 400 linear metres of pile cages per hour. The pile cages are continuously reinforced and are welded at each time the helical wire crosses a main bar. These Robots are designed and manufactured in Denmark.
The process starts with deliveries of the rebar in coils. The coils that are used for the main bars weight 4 Tonne each and the coils used for the helical bars weigh 950kg. We store around 500 Tonne of coil within the robot shed; this is approximately one month’s usage.
The operator programmes the Robot to manufacture the length of cage required from the production schedule and changes the former to the correct size for the cage section. Once this is complete, the Robot can run.
As the cages are being manufactured, spacers are added to the cage to ensure that the correct cover is achieved on the soffit sides and ends of the piles.
The cages are stored on bogey’s or in the robot shed awaiting call off. Each of the cages are individually identified with a label put on at the manufacturing stage. From this label, all the coil charge (batch) numbers can be traced.
2. Batching Plant
The Batching Plant is where we manufacture the concrete for our piles. We manufacture circa 40,000m3 of a concrete which allows us to pile in most ground conditions, even that which is contaminated.
The capacity of the batching plant is 60m3 an hour.
Constant communication between batching and casting is required so that the concrete is manufactured and delivered down the chute in to the casting hopper when needed.
Raw materials are delivered by lorry, the sand and aggregate in 30 Tonne tipper and the cement and PFA in 30 Tonne powder transporters. The sand and aggregate is stored in the bins and the powders are stored in the Silos. Cubes are taken for every 50m3 of concrete batched and are sent to a UKAS accredited laboratory for crushing and compliance checks.
3. SAMM Shed – Casting and Curing
SAMM is an abbreviation of “Semi Automated Mould Movement” and is a carousel system. The SAMM system contains a mixture of various moulds for the section sizes required by our customers and holds 45 moulds. Contrary to a static mould facility, each of the processes remain static and the moulds move around the facility and are cured once cast in a temperature and humidity-controlled curing chamber.
After cleaning takes place, the mould end plates are inserted into the moulds and pulled tight onto the end spacers of the cage. The trophy boxes form a void in the end of the pile for use with our Centrum D Joints. The void is formed by using a cardboard sleeve which acts as a de-bonder between the concrete and the void former on the trophy box. A pin is then inserted through the void former, this creates the void in which the Centrum D Joint pin is inserted out on site.
The mould travels beneath the casting hopper and the individual troughs within the mould are filled with concrete. Concrete is called for via the radio, volumes are confirmed, and the batching commences. The concrete is delivered to the casting hopper via a direct chute between the batching plant and the hopper. Beneath the casting machine are multiple doors, each containing sensors that monitor the meniscus of the concrete and open and close accordingly ensure that the correct fill level is achieved. Upon completion of casting the lifting hooks and a label plate are added to the piles. The mould then travels into the curing chamber.
The curing cycle is a minimum of 16hrs. The next stage of the process is de-mould, inside the SAMM Shed the mould travels to a station where the mould opener is activated, this opens the mould just enough to allow the trophy boxes and end boxes to be removed after the pins. The pile labels are stuck to the label plates, these contain the piles individual references and full manufacturing details giving us full traceability. A Schmidt hammer is used to check that the concrete is sufficiently cured to lift, if so, the mould then travels outside for the piles to be de-moulded and put into stock.
4. Pile Storage Yard
Our yard contains 5 cranes, 3 gantry cranes and 2 Goliath cranes. Dependant upon the mix of piles in stock, the yard can hold up to 100,000 metres. As part of the de-mould process, piles are constantly going into stock whilst the SAMM is running and in between times trailers are loaded with piles for deliveries to customers.
From the order, paperwork is generated which is used as a pick list out in the yard. Each pile that is picked and loaded in scanned and it’s individual bar mark is registered. From this full traceability of the pile is achieved as described in the other areas of the works.