Investment decisions

Honing at Stansted-based aerospace repair services provider, Kearsley Airways had been restricted by its existing honing capacity, requiring it to regularly resort to manual honing of larger aircraft components, such as the landing gear of C130 Hercules military aircraft. The company regularly takes in aircraft repair work on everything apart from engines. Not only was this inefficient, but it also posed problems with consistency due to the physical effort involved in the process. This effectively left Kearsley with two options – subcontract any large honing work or invest in additional horizontal honing capacity.

Martin Bowman, Kearsley Airways' general manager, quickly ruled out a new machine as the cost couldn't be justified, so was in the process of investigating subcontracting options when a conversation with Steve Hunt of Delapena Honing Equipment opened up a third possibility, that of a re-engineered Delapena Tubehone machine.

“The sector that we work in applies significant emphasis to on-time deliveries so having as much capacity in-house, where we can control both quality and leadtimes is important. When Steve suggested the option of a re-engineered machine, at a significant cost saving over a new machine of the same capacity, it was a relatively simple decision to make,” Mr Bowman explains.

Much of the work that requires honing at Kearsley is either manufactured from hardened material or has a chrome plated finish, so honing is an ideal solution for repairing damage to bores that can be up to 1.5m in length. Mr Bowman says it would be possible to apply other machining methods, but the risk of scrap would be too great.

“Typical of the honing work that we undertake is to remove service damage from undercarriage systems which have been subjected to landings in hostile environments. These components can be valued at up to $56,000, so to risk scrapping one is not an option – as is releasing something of that value to a subcontractor. Investing in the Delapena Tubehone eliminated all of these risks and created the potential to win new business.”

The Tubehone machine at Kearsley Airways was completely re-engineered at Delapena's factory in Cheltenham and fitted with an updated control system – the same as is used on the company's vertical Powerhone machines. Tubehone machines are ideal for applications in the manufacture of heavy-duty components such as aircraft undercarriage, propulsion systems, and particularly precision hydraulic ram systems. The Tubehone machine at Kearsley Airways has a maximum hone length of 1.5m and the powerful motor allows high levels of stock removal.

“Tubehone machines are part of Delapena's longstanding pedigree of building honing machines,” reveals UK sales manager, Steve Hunt. “They are sturdy and powerful machines that accomplish simple honing tasks very well and with bags of power available, they're ideal for heavy-duty work. In recent years the trend has been to move away from machines of this type, but with tolerances getting tighter and more exotic materials being used in manufacturing, heavy-duty honing is definitely generating more interest.”

New Tubehone machines from Delapena are available with stroke lengths ranging from 1.5m up to 15m with key features being its ease of use and simplified control of the honing process, which enables maximum uptime.

The machines also feature high precision feed units and high capacity drive systems along with a powerful servo-motor (up to 9kW) driving the honing spindle, while a three-step transmission controls spindle speed up to a maximum of 450rpm.

A Tubehone's versatility doesn't end with its honing performance in terms of bore length and diameter – it can be configured to meet an individual customer's specifications. Typical upgrades include expansion of the clamping area and the ability to ‘short stroke' anywhere along the bore. Those in the honing world will appreciate this ability to eliminate tight spots with a machine that is both simple and flexible.

Delapena Honing Equipment
www.delapena.co.uk