Formed in 1911, Sheffield-based Padley & Venables is a leading UK manufacturer of construction tools that are sold world-wide.

Its on-going drive for productivity and quality recently saw the company install two Doosan Puma 3100M turning centres and a robotic loading system — plus machine-related metrology equipment from Blum Novotest.

Padley & Venables (www.padley-venables.com) makes tools for rock drilling, quarrying, mining, tunnelling, construction, civil engineering and the demolition industries.

It has subsidiaries in Germany and Australia and exports to more than 55 countries, which means that conforming to global quality standards is essential.

Quality manager Steve Foster says: “We were getting to a point where we had to renew some of our older lathes, and we thought we would take the opportunity to speed up the production process by using automation. By doing this, we have increased productivity by over 40%; moreover, we can run the cell unmanned during the period between shift change-overs.”

The two Doosan Puma 3100M turning centres and the robot for loading and unloading were installed as a complete cell, along with Digilog metrology systems from Blum Novotest Ltd, Burton on Trent (www.blum-novotest.com).

The cell, which runs 24/7, is dedicated to manufacturing numerous families of steel drilling rods and connecting rods for the rock-drilling industry.

While the robot has eliminated the need for an operator to load and unload and the Doosan machines have improved productivity, without the Blum equipment, Padley & Venables would still need an operator at the cell to check the finished parts.

Mr Foster says: “The Digilog equipment is central to the operation of the cell. Without it, we wouldn’t be able to run the process as a robotised cell, as the operator would have to be present to gauge every single component to ensure it met our quality requirements.

“It is pointless having an automated cell and an operator opening and closing the machine to inspect every part. The Digilog probe checks that the part is within tolerance.

“If it is, the machine continues. If not, the machine stops and ‘alarms’ the operator to investigate further; the Digilog software shows where the problem has occurred on an integrated touch screen.”

'Working in harmony'

Quality and consistency are critical factors for Padley & Venables, as its components have to work with parts manufactured by other companies.

In the cell, the Digilog probing system checks the workpiece in situ, thereby ensuring that the required standards are achieved before the component leaves the machine tool.

When making connecting rod parts, the Doosan Puma turns the thread while the Digilog follows the threading process, scanning the thread to ensure that the part is correct — with no operator involvement. This allows the cell to run unmanned 24hr a day, if necessary.

Also connected to the Doosan turning centres is Blum Contour Scan (BCS) 3.0 software, which is displayed on an industrial Windows-based PC attached to the machine via a swivel arm. The BCS software shows the operator two individual displays and two sets of results.

One display gives the nominal values, as well as the details of the part that has just been machined, while the second shows the current scanned result along with the pre-set wear and extreme limits. This enables the operator to pre-empt tool breakages and prevent the occurrence of faulty parts.

Commenting on the installation at Padley & Venables, Blum Novotest UK managing director David Mold says: “While this customer places a high emphasis on quality, the core reason for implementing the Blum Digilog system is to achieve a completely autonomous automation system that permits unmanned production and delivers the cost and productivity benefits associated with automated production.

“This installation successfully demonstrates that probing is not only applicable to precision manufacturing but should also be considered for automation.

“Furthermore, the application on the two Doosan machines highlights the ability of the Digilog equipment to perform in harsh environments with swarf and coolant flying around the work envelope.

“Like all Blum probing systems, the Digilog incorporates our Shark 360 technology; this offers patented multi-direction measurement technology designed to significantly increase measurement accuracy when performing off-centre probing with cranked styli.

“This is ideal for harsh environments such as measuring the form of threads on a turning centre when covered in coolant and swarf.”

The success of the Blum system has now led Padley & Venables to look at a tool breakage detection package for two of its DMG EVO50 machining centres.

The company is having issues with tool setting, and it says that installing a Blum Laser Control NT tool-measuring system and inspection probes will allow it to automatically measure tool lengths and diameters; and because the Laser Control NT can also monitor the wear on individual inserts, cutting edges and flutes, it can pre-empt catastrophic tool failures and prevent parts being scrapped.