Following the recent installation of the latest Miyano BNE-51MSY multi-axis mill-turn centre, Wednesbury based precision sub-contractor Machine Tech Engineering (MTE) has been able to slash production lead times on batches of hydraulic bodies from three weeks for the first operation plus a week for the second to machining the batch complete in just five days.
The decision to go for the 51 mm bar capacity Miyano continued the already accrued benefits from introducing new machines, for instance, a Citizen A32-VllPL CNC sliding head mill-turn centre also installed recently, has just been the source of orders from a new customer in the brewing industry for 1,000 batch quantities of stainless steel pump valves. According to MTE director Warren May: “Without the Citizen we would never have dreamed of even quoting for such parts as we would be uncompetitive. But the Citizen A-Series is very quick and powerful enabling simultaneous cutting cycles.”
MTE has some 30 machines, seven bought under the Citizen brand in its freehold 7,500 ft2 machine shop from which turnover is projected to top £1 million in 2017. With recent CNC sliding head installations, MTE had already benefitted significant business increases and improvements in productivity from the ability to combine operations into single cycles.
Commenting on the expansion, Warren May said: “ As the recession was biting in 2008 we felt we were becoming ‘Pooper Scoopers’ because as we were such a lean operation with low overheads, customers were flocking to our doors for quotes seeking reduced prices. As a result we picked up a lot of orders. In retrospect, we can see many of the parts were what competitors wanted to avoid, but it extended our customer base, helped us gain more expertise and led to future work helping us to be more profitable and especially as we introduce newer technologies.”
The current customer base covers automotive related including manufacture of special tools and spares for out of production classic vehicles, hydraulics, security, special fasteners, injection moulders petrochemical and medical sectors. As a result materials processed include, carbon and stainless steels, brass, Tufnol and phosphor bronze.
Now employing nine people, both Stewart and Warren are involved in setting machines as well as Stewart’s son Ashley who is an ex-production apprentice. While the head count is small, it is highly skilled and much of the work involves resetting machines for 75 per cent of repeat orders. Batch sizes on the Miyano, although early days is between 100 and 300 while each Citizen has varying batch sizes between 500 and 60,000. Most repeat orders involve machining for controlled stock holding which can extend the run time between settings and enables a fast response to customer delivery.
The 8-axis Miyano BNE-51MSY with IEMCA Kid 80 bar feed has created a massive advantage in lead time reduction for MTE due to the ability to overlap in a cycle and cut with up to three tools simultaneously. The machine has two 12-station driven turrets one with three axes, the other with two that can service either or both spindles at the same time.
The main spindle has a 15 kW drive and the secondary 2-axis spindle is powered by a 7.5 kW motor. Both spindles have a 51 mm capacity with a maximum speed of 5,000 revs/min. Each driven tool position is ideal for milling with a 2.2 kW high torque 25 Nm drive and programmable speed of 6,000 revs/min.
In producing the hydraulic body out of 38 mm bar, a 22 mm spade drill is used to a depth of 57 mm, then using a special flat bottom tool a face and corner relief is created at the bottom of the bore prior to final boring to 0.03 mm size. A further bore is then drilled and reamed 11.9 diameter to 0.03 mm tolerance by 76 mm deep and the initial bore threaded 1” x 20 TPI Whitworth by 8 mm deep. The OD is then turned and threaded 11/2” x 16 TPI Whitworth over 100 mm length.
The part is then taken by the 3-axis secondary spindle, faced and a 30 mm A/F hexagon milled by 20 mm long and a 6 mm shoulder created which is straight knurled. A through bore is then drilled to break into the 11.9 mm bore which is then tapped 7/16” x 20 TPI UNF by 26 mm deep.