Burnett & Hillman has become a ‘brand name’ in its role as a major manufacturer of hydraulic adaptors and associated fittings that supplies into around 90 per cent of the world’s countries with a known customer base that exceeds 1,000 names. In addition, parts are also sold through significant numbers of distributors and stockists.
Its operation is mind-boggling having a standard range of over 4,500 different machined parts of which 99 per cent are held in stock for next day delivery. While its machine shop processes some 40,000 components a day consuming 200 tonnes of mild steel a month, these contribute to a massive year-on-year tally of over 10 million individual machined parts of which a quarter are directly exported.
Nestling in the small Somerset village of Wrington, south of Bristol, this family-owned business still uses multi-autos to meet its greater volumes. However, for smaller demands and batch sizes typically from 1 to 250 plus samples, a progressive addition to the production capability has been the highly successful installation of turn-mill centres including five Miyano multi-axis machines from Citizen Machinery UK.
Daniel Burnett, general Manager (right) demonstrating ease of programming for the next batch on the Miyano BNA-42GTY to maintain daily production total of 40,000 parts.
Following the reliability and consistent performance capability obtained from the first 12-axis Miyano ABX-51TH3 fixed-head turn-mill centre with two spindles and three all-driven 12-station tool turrets installed in 2008, three further smaller capacity Miyano BNA-42GTY’s were laid down in 2015 and 2017. In October 2018, the fourth BNA-42GTY was commissioned. The company has invested some £500,000 over the last two years in the business.
Said General Manager Dan Burnett: “We face ever increasing demands for non-standard parts, smaller batches plus in-house store top-ups and due to the specification requirements of customers into our production, quality is the prime requisite followed by delivery. Here, the first installation of the Miyano ABX-51TH3 gave us improved capability to achieve and still maintain these changing needs introducing far greater levels of flexibility and most important, consistency of production to meet the standards required.”
As a result, the family firm made the decision to standardise on Miyano fixed-head turn-mill centres for smaller bar capacity up to 42 mm which lead to the multiple installations.
The 10-axis, plus three auxiliary axes, BNA-42GTY is the top of the Miyano BNA range with 42 mm bar capacity. It is configured around two spindles having 7.5 kW, 6,000 revs/min on the main and 3.7 kW, 5,000 revs/min for the secondary-spindle. It has a single 3-axis, eight-station turret which is carried with the two spindles on a single platform-like surface table structure.
The turret features half-indexing that provides 16 driven-tool positions plus a 13 tool gang vertical toolpost having three driven tool positions brings the total machine capacity with multiple tool holders up to 45 tools. The machine is able to accommodate 3-axis overlap machining with three tool simultaneous cutting involving either or both spindles.
Most of the material passing through the Miyano machines is hexagon based and here, the rigidity gains from the heavy cast iron bed and hardened and ground slides on the common platform-like surface table structure enables maximum advantage from speeds and feeds to be maintained without effects of vibration. This means general tolerances are 0.05 mm and surface finish 63 micro-metres on sealing faces is also easy to maintain.
Commenting on the levels of flexibility now available helping to supply into such diverse hydraulic sectors, the Miyano installations create the ability to achieve enquiry-to-quote within 12 to 24 hours. A new turned adaptor or fitting can often be supplied within two weeks and an out-and-out special, within four weeks.
This is aided by the number of tool positions enabling a standard suite of tooling to be held on each Miyano machine with the largely ‘self-taught’ setters (with Citizen Machinery support when required) programming directly at the control. Here, most setting up is achieved between 20 minutes and two hours.
Said Mr Burnett: “It has even been known for a customer with an extremely urgent need to be supported following a call in the morning and getting a response where we are able to set up the Miyano and machine parts in the afternoon and ship out that same evening.”
