Leading precision engineering specialist CMS Cepcor has recently bought two new large-capacity lathes and a large vertical machining centre to machine large, high-precision complex ‘crusher’ spares and replacement parts for the global mining, quarrying, aggregates, demolition and recycling industries.
The Doosan machines — a Puma 700XLM, a Puma 400LB and a Mynx 7500/50 — were installed at the company’s new 30,000ft2 facility in Coalville late last year. Moreover, most of the replacement parts manufactured on the new Doosan machines — supplied by Mills CNC Ltd, Leamington Spa
(www.millscnc.co.uk) — are destined for export. Indeed, some 70% of CMS Cepcor’s turnover now derives from its overseas business, and last year the company received a Queen’s Award for Enterprise (international trade).
Crushers are essentially machines designed to reduce large rocks to smaller rocks. In quarries, they are used to produce graded aggregates; in mining, they are used to crush the ore into more manageable sizes before grinding.
Crushers are costly items and are usually located on-site or adjacent to mines and quarries. However, the nature of the crushing process — high pressures, severe forces and abrasive materials — means that the machines get through significant quantities of ‘consumable’ parts. Failure to replace worn-out parts in good time can result in breakdowns and equipment down-time.
Chris Sydenham, CMS Cepcor’s technical director, says: “Crushers are high-value pieces of capital equipment, so they require high-quality and reliable replacement parts. Few of the OEMs provide a good service in the after-market when it comes to supplying replacement parts for their equipment, and many of them charge exorbitant prices — and have long lead times.
“This is where we come in. For more than 50 years, we have been using our technical expertise and reverse-engineering skills to manufacture high-performance cost-competitive replacement parts that are widely recognised in the industry as being as good as — if not better than — those available from the original equipment manufacturer.”
Increased capacity
CMS Cepcor manufactures and stocks a wide variety of replacement parts to suit primary, gyratory, cone, jaw and impact crushers for its growing international customer base. In response to market demand for its replacement parts — and in a bid to boost its productivity and performance to take advantage of the relative economic buoyancy of the global mining and aggregate sectors in particular — CMS Cepcor has significantly increased its manufacturing capacity and capabilities with the three new Doosan machine tools.
Mr Sydenham says: “We are continually improving our manufacturing capabilities. We need machines that are powerful, reliable and flexible. Indeed, the nature of the parts we manufacture means that machines need to be versatile and must be able to undertake a range of applications from high-accuracy heavy-duty machining right through to fine finishing. That said, our decision to invest in Doosan technology wasn’t only about machine performance, but also after-sales service and support. Mills provides a complete package that is difficult to beat.”
The Doosan machines are being used to machine a diverse range of complex, high-precision replacement and wear parts that include eccentric shafts, sleeves, pitmans (the main moving part in a jaw crusher), section rings, shaft nuts and bushings, for example. The largest lathe purchased by CMS Cepcor — the Puma 700XLM — is a box-guideway lathe capable of machining workpieces up to 5,050mm long. The maximum workpiece weights are 1,400kg for chucking work and 8,900kg for shaft work.
The spindle is driven by a 45kW motor via a twin-speed gearbox that gives a maximum speed of 1,500rev/ min, and the 12-station fast-indexing turret offers a driven-tool capability (11kW 3,000rev /min). The machine was also supplied with a number of options; these included an automatic (tow-along) tailstock, a specialist tooling package, an automatic touch-type tool setter, hydraulic and manual steadies and a swarf conveyor.
Parts produced on the Puma 700XLM (either to order or for stock) are characterised by their size (up to 1m in diameter and up to 5m long), their complexity, tight geometrical and dimensional tolerances, and excellent surface finishes. Moreover, the nature of CMS Cepcor’s business means that batch quantities are low and that cycle times are long (typically more than 5hr).
In conclusion, Mr Sydenham says: “Through our continuous-improvement programmes and investment in new technologies, we are better prepared for the future, and we can focus all of our resources on producing high-quality replacement parts delivered on time and within budget.
“The investment in the three new Doosan machines represents an important step in our development and re-affirms our ambition to maintain our position as one of the leading manufacturers and suppliers of premium crusher parts.”