LJH convey for Hanson at Batts Combe
- 13 February 2006
- Company & Industry News
Situated on the edge of Cheddar village, Batts Combe Quarry has been operating since the early 20th century and is owned and operated by Hanson Aggregates. Currently processing 4000 tonnes of limestone per day, one third of which is supplied to an on-site lime kiln, the remainder is sold as coated or dusted aggregates. Recently the company has made a �1 million investment in a new washing plant. Designed to operate at a maximum of 500 tonnes per day the purchase and installation of the plant has been commercially driven and also provides the company with an increased level of health and safety within the site.
Commissioned in January 2005 the new wash plant has provided Hanson with the ability to sell quality materials to its local markets, previously only supplying scalpings the new plant produces a 20-5 material and a good quality sand. The 20-5 can be stocked or supplied to Hanson�s own ready mixed concrete plants; the production of sand has also benefited Hanson as this has allowed them to establish a new local market for this product.
Several companies have been involved with the supply and build of the new plant including local company LJH of Chantry, near Frome.
Working closely with other suppliers LJH installed and commissioned a feed hopper, conveyors and screen walkways including screen chute and flume, splitter chute and all the supporting steelwork.
Material is fed into the LJH 22 tonne belt feeder hopper, complete with 4000mm wide self tipping grid. With 100 x 20mm flat bars set at a 75mm gap it has a duty of 80tph of -40mm limestone scalpings with a belt width of 750mm, and drum centres at 5.9 metres the belt speed is variable and is screw tensioned at the tail.
The material is then fed onto the wash plant feed conveyor (approx 65 metres in length). Operating at 80 tph this conveyor is set at an 11 degree maximum incline allowing safe vehicular movements under the structure and to clear existing structures. This conveyor has a 600mm belt width with a gravity tension take up and is driven by a 7.5kW shaft mounted unit powering a 426mm drive drum with a 10mm diamond pattern rubber covering.
Additionally a 324mm dia tail and bend drum and a 406mm dia G.T.U. drum all have shafts incorporating Cooper series 01 split bearings, whilst impact idlers are 122mm dia and troughing and return idlers are 102mm dia. A Beckford series 1001 single idler belt weigher was also fitted along with torsion type belt scrapers fitted with a polyurethane blade and �v� return plough.
LJH also built and installed a secondary surge bin feed conveyor with a duty of 50 tph of -40, +5 limestone scalpings which is installed at a 17.6 degree angle. With drum centres of 54.7 metres length, the belt width is 600mm with gravity tension take up and is driven by a 5.5 kW shaft mounted unit powering a 426mm drive drum over 10mm diamond pattern rubber covering.
Finally a stockpile conveyor was installed with a duty of 50 tph of -40, + 5 limestone scalpings. Set at an incline of 18 degrees this conveyor has drum centres of 15 metres approx and a belt width of 600mm with screw tension take up at the tail. Driven by a 3 kW shaft mounted unit powering a 426mm dia drive drum over 10mm diamond pattern covering incorporating a 324mm tail drum. With all shafts utilizing Cooper series 01 split bearings this conveyor is also fitted with a torsion type belt scraper with polyurethane blade and �v� return plough and a Beckford series 1001 single idler belt weigher.
LJH also completed the project by manufacturing and installing a main supporting structure constructed from suitably sized rolled steel sections rigidly tied and braced diagonals. All walkways were 1000mm wide galvanized flow forge walkway and included all sides of the screen and hydra screen, all were completed with galvanized hand railing and kick boards. Stairs were 600mm wide set at a 42 degree rake angle with welded durbar treads with all steelwork surface finished to a high standard.
LJH also supplied an under screen chute and flume which was fabricated from 6mm plate with suitable bonded rubber linings With an under pan at 22 degrees, flumes were 400mm wide x 350mm high declined at 15 degrees.
A rejects splitter chute was also supplied; fabricated from 6mm plate with a gate activated by an Elram Electro hydraulic actuator.