Safety Inspections and Light Curtains are helping keep
workers safe at BMW's diecasting plant
Cylinder heads for diesel and petrol
engines are highly-stressed,
precision components, which must
meet demanding mechanicSafety Inspections and Light Curtains are helping keep
workers safe at BMW's diecasting plant
Cylinder heads for diesel and petrol
engines are highly-stressed,
precision components, which must
meet demanding mechanical and thermal
requirements. For a premium brand like
BMW, great attention is therefore
focused on the process control for
producing these essential components.
Leuze electronic gives the same level of
attention to the machine safety inspections
it provides BMW at the plant, and which it
has recently started offering in the UK.
BMW's 300,000 mÇ plant in Landshut
near Munich, is key in the development
and production of cylinder heads and
other light-metal cast components, such
as crank cases, plastic components and
rebuilt engines for practically all BMW
Group vehicles. The 3,000 strong
workforce have worked on everything
from BMW motorcycles and cars through
to their Formula 1 racing cars.
In recent years, in response to an
extensive risk assessment, the chill casting
production area has been equipped with
safety light curtains from Leuze electronic.
Two particular danger points during
this process are the horizontal movement
of the ejection cylinders when releasing
the mould, which can crush the operator
and when the deflection arm swivels as it
takes the cast component from the
machine to the unload position, which
could cause seriously injure the operator.
Therefore the operator starts the casting
process by pressing a start button outside the
die-casting area, which is guarded by Leuze
electronic's COMPACT light curtains.
During the 5 minute cycle time, nobody is
allowed into the casting system area.
Identifying such risks and inspecting to
ensure physical or opto-electronic
protection is in place to prevent such
injuries is the purpose of Leuze
electronic's machine safety inspections.
To ensure that no one can enter these
danger areas during the cycle time because
there is movement, especially during the
automatic removal of the cast component,
BMW relies upon Leuze electronic's
COMPACT safety light curtain. These light
curtains along with the machine safety
inspections provide an integrated safety
solution which meets all the relevant
requirements and gives reliable protection.
The entire die casting area is now
guarded with COMPACT safety light
curtains, most of which have a resolution
of 30mm and an 18m range. Horizontal
danger zone guarding, on welding and
assembly lines or robot cells is widely
used, plus 14 mm resolutions curtains
providing hand and finger protection on
presses and punches, for example.
The COMPACT safety light curtains
comply with type 4 in accordance with
IEC/EN 61496. In addition to reliable
detection of protective field interruptions,
they are also highly immune to interference
ensuring high machine availability.
Additionally, their integrated auto-analysis
system enables easy and efficient on-site
diagnostics.
System with guarding
Safety-related considerations and
manufacturing conditions such as
transportation corridors or stillage loading
positions resulted in the guarding floor
plan for the chill mould being trapezoidal
in shape. Therefore the solution was to use
a COMPACT transmitter, a COMPACT
receiver and two UMC Deflecting Mirror
Columns, with one having a reflection
angle of over 90 degrees and the other
having a reflection angle of less than 90
degrees. The mirrors guard the area
between the chill mould and the transport
lane across a distance of 3 metres. Both the
transmitter and the receiver are positioned
4 metres across from the mirrors on the
other side of the casting system, close to the
control cabinet, providing access guarding
for the trapezoidal area.
On its way via the mirror to the
receiver, the light beam must travel 12
metres and therefore to speed alignment
over this distance when even a tiny
deviation in the angle would cause the
light beam to miss the receiver, Leuze
electronic's Laser Alignment Aids were
used. The Laser Alignment Aid is
mounted directly on the transmitter and
clearly marks the target point of the
sensor beams with a red laser light,
enabling just one person to commission
the perimeter guard easily and efficiently.
Reliability with shock
absorbers and enclosure
Transmitters, receivers and deflecting
mirrors are positioned in free-standing and
sturdy UDC device columns, which are
firmly anchored in the floor. The UDC
columns enable precise vertical and axial
alignment and anti-vibration mounts in the
base of the column provide isolation from
the vibrations caused by forklifts driving
past carrying 600kg ladles of metal
The UDC device columns are enclosed
again at the BMW plant by a solid steel
column in order to guarantee reliable
protection against melt splashes, even with
a direct impact. This enclosure is also
anchored in the floor with shock absorbers.
Conclusion
By equipping the die casting system with
COMPACT Safety Light Curtains, BMW
have been able to manage the risks
identified, achieve the relevant declaration
of conformity, and benefit from the high
availability of the machinery.
