LEAD FEATURE STEP-BY-STEP AUTOMATION
skilled labour availability issues – there is no ready pool
of labour around Tiverton. The latter is an industry-wide
issue and is despite the company being an avid
apprentice trainer for 25+ years (see extended online
article). About a third of the company’s management
team are former apprentices – including the chairman,
who has been in place for fi ve years. “We wouldn’t have
grown without this,” Engstrom emphasises.
With Hepco having recently established a presence in
China and strengthened its South Korean branch, and
with the chairman keen to look at other new markets,
growth is likely to be the order of the day for some time.
A cost-effective solution to overcoming production and
delivery constraints is therefore key.
In line with this, Hepco is currently on a world-class
manufacturing journey, with some £2.5 million being
invested in Tiverton over the past couple of years alone.
At the helm and driving these changes is managing
director Peter Fanshawe, who has been with the company
for 30 years, seven of these in his present position.
A number of threads underpin this effort, but a recent
and key one is automation, with this being pushed
forward via collaborative robots for loading machining
centres (cobots – robots that can work safely alongside
humans). Indeed, Hepco’s adoption of Universal Robots’
UR10 units (Applied Automation, https://is.gd/vituzi),
which now stands at four, probably puts the company in
the top tier of cobot users for machine tool loading
purposes in the UK, for a company of its size, Machinery
suggests. The company additionally has one KUKA
industrial robot-served machine tool, while further cobot
installations up to another half a dozen are envisaged,
Engstrom reveals, although they may not be identical
units, he adds.
It all started in late 2015 with the KUKA installation
serving an existing FANUC Robodrill (https://is.gd/
ematin), but why? “Initially, we didn’t think that robots
were relevant,” the group manufacturing director says.
“We are not a high volume parts manufacturer, like
Braintree, so it was always felt that, as we were doing
10, 20s, maybe a few hundred here or there, it would
take longer to set up than run. But technology is moving
on, so we kept an eye on it. The investment to get the
process developed is time; once it is running, it is just
as quick as changing a tool over in a machine.”
A RoboDrill T21i CNC milling machine using a KUKA
‘KR 10 R1100 sixx’ (KR AGILUS) was chosen for the fi rst
project. This enables Hepco to machine unmanned
overnight, increasing production capacity for standard
carriage plates. HepcoAutomation, part of the Hepco
Group of companies responsible for delivering
automation solutions, is an approved supplier for KUKA
Robotics (https://is.gd/viyuxo), in fact.
Sawn blanks are loaded into two rotary tables from
where the robot takes one and loads it to the machine.
Following machining, the robot returns the fi nished
carriage plate back into the exact space in the carousel
from where it was taken. There is space for 80 plates in
the rotary tables (video: (https://is.gd/ciquva)).
STACKS OF WORK
The cycle time depends on the size of the carriage
plates, but can be between 9-14 minutes per plate,
including the robot changeover time. Again, depending
on the product, the complete batch cycle time is around
Appropriately, the carousel holding the metal plates is
made using Hepco’s PRT2 ring guide, indexed through an
Omron HMI PLC as necessary. And the sliding safety
doors between machine and robot are fi tted with Hepco’s
DAPDU2 dual-action linear actuator.
The 10 kg capacity KUKA unit is not a cobot, however,
and the machine can only be run in an automated
fashion; fi ne for the high volume carriage plates, but for
lower volume parts a different solution was required. Yet
with the principle of automation demonstrated, thoughts
turned to more of the same, but at reduced capital cost
and with more fl exibility. “In the latter part of 2016, we
came across UR robots,” says Engstrom, and the journey
with cobots began. The cost to install is between
£20,000 and £30,000 all in, which is better than half
the cost of an ‘industrial robot’ solution, he offers.
First, a second similar FANUC Robodrill was fi tted with
a UR10 and two carousel units, allowing for faster
changeover between parts, but the machine was still not
used in manual load mode. For lower batch numbers and
displayed in the
Below: a UR10 cobot in the
process of changing parts on a
FANUC Robodrill, but automated
loading is the only possibility
www.machinery.co.uk @MachineryTweets May 2018 11