Lean and green

Deep hole drilling with its requirement for copious amounts of neat cutting oil can be a messy process, contributing to the negative image of engineering as a dirty business that poses a potential risk to health, safety and the environment. However, as Solutions discovers, Hone-All Precision is keen to dispel this myth.

Hone-All's recent decision to relocate its subcontract machining operations to larger refurbished premises in nearby Leighton Buzzard, Bedfordshire was prompted by the need for increased production capacity and a more efficient process flow from raw material through to finished component, along with easier access to and from the factory. However, relocation has allowed several environmental and related initiatives to be implemented as part of the refurbishment project, all of which have impacted favourably on the company as a whole.

“While the cost of these initiatives does have a direct effect on the bottom line, it is balanced over time by a reduction in our direct costs and by less easily quantified benefits such as a better working environment,” says director Andrea Rodney.

“Our machining capability continues to be components up to 250mm diameter by 3m long but doubling our floorspace to 20,000ft² has allowed additional investment in machine tools. This is a vital part of our lean manufacturing strategy, which has shortened delivery times and minimised the movement of heavy material and components through the factory.

“We have also reduced energy usage by installing a new roof with clear panels to let in natural light, and opting for Carbon Trust approved, highly energy efficient daylight quality lighting throughout the factory.” 

Keeping the house in order

The expertise to produce high length-to-depth ratio holes, often in difficult to machine materials such as Inconel and Hastelloy, while guaranteeing excellent surface finish and straightness characteristics is key to Hone-All Precision's steady progress over the past decade.

In terms of deep hole drilling this equates to a surface finish of 0.8µm/32 CLA and a total runout (TIR) of 0.025mm/25.4mm. Typical components requiring deep hole drilling up to 30mm diameter include con rods, drive shafts, steering columns, electronic housings, injection mould tools, prosthetics, rotors, actuators and landing gear. For holes with a diameter greater than 30mm, the alternative is deep hole boring.

Hone-All Precision's commitment to maintaining its specialist skills in deep hole drilling, boring and honing, as well as its one stop shop machining capability, is backed by an emphasis on good housekeeping, safe working practices and a comprehensive environmental policy. Every machine tool was inspected before the move, re-engineered, rewired and, when installed in the new factory, subjected to a comprehensive safety check. And the increased floorspace has contributed to a shopfloor layout that ensures a smooth and logical workflow, thereby minimising work-in-progress and eliminating potential production bottlenecks. 

Aims and objectives

As regards environmental considerations, Hone-All Precision's publicly stated aim is: ‘To educate and encourage our employees to realise and understand their responsibilities with regard to conservation; to exceed the requirements of all relevant Government regulations at our site; to minimise our energy consumption; and to recycle waste material from production into new production or transfer it to a recycling company to dispose of in a controlled manner'.

In practice, a factory wide clean air blower and filtration system with ceiling mounted extraction units positioned strategically throughout the machining area prevents the build up of oil mist, while machine tools are located in drip trays, with billets drained on mesh covered drip trays, to avoid oil spills and minimise wastage.

Machine tanks are no longer filled by hand as oil tanks equipped with retractable hoses are situated at one end of the mezzanine floor that runs the entire length of the building. Swarf is removed via conveyors with integral drip trays that are fitted to some machines whilst on others it is removed to hoppers with drainage facilities and then spun to recover the neat oil before being sent offsite for segregation and recycling.

“The recent accreditation to the AS9100 aerospace quality standard, while not directly influenced by health, safety and environmental issues, could not have been achieved had we remained within the restrictions of our previous premises,” says Mrs Rodney. “Winning business in advanced technology industries such as aerospace, motorsport, and oil and gas is a major challenge and our success depends to a large extent on the customer's perception of the quality of the products and services on offer.”

Hone-All
www.hone-all.co.uk