ENGINEERING
SERVICES - LATEST NEWS
| CHAIRMANS
SILVER AWARD FOR INNOVATION |
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BAe Systems
asked for a manufacturing method / workholding solution for
the manufacture of stringers which would generate cost savings
and reduce manufacturing time. Working alongside BAe Systems
own tool designers and planning engineers HYQUIP successfully
designed, manufactured and installed a hydraulic clamping system
and production methodology which exceeded all targets.
Stringer
manufacture is a three stage process and sections are machined
from H section aluminium extrusions of varying lengths. Each
machining operation required precise location and rigid holding
of the material. HYQUIP quickly recognised that a significant
proportion of time and cost in the manufacturing operation was
represented by the need to clamp and unclamp the aluminium sections
at each stage of the process.
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HYQUIP
engineers designed a workholding system incorporating tubeless
manifolds for vacuum clamping with integrated hydraulic swing
clamps for stage 2 and a bespoke hydraulic vice system for stage
3 using Hilma-Roemheld products. This together with conventional
hydraulic swing clamps and work support technology for stage 1
dramatically reduced the time taken for successive clamping operations.
Stage
1 - In the first stage of manufacture, ‘slabbing
of the aluminium billet’, two pairs of stringers are mounted
on a 47' long fixture. Clamping and unclamping is virtually instantaneous
and completely hydraulic using Roemheld swing clamps, work supports
and valves spaced at intervals along the length of the machine.
Stage
2 - In the second ‘prime machining’ stage,
the billets are clamped onto a vacuum labyrinth with precision
jointing to ensuring an effective clamp. Components are then clamped
against a datum edge using Roemheld hydraulic swing clamps.
Stage
3
- The final production phase, ‘contouring of the stringer’,
was the most challenging. At this stage in the manufacturing process
stringers are extremely slender and the flexibility of the material
and machine vibration made precise location of the components
problematic. The solution was provided by incorporating special
hydraulic cylinders in standard twin self centring Hilma vices
spaced at 400mm centres. This ensured a location against vertical
datum pads before applying a light grip.
The
complete system was supplied and installed ahead of schedule allowing
BAe Systems to bid successfully for a Boeing Stringer contract.
The first set of stringers were successfully delivered on time
and to specification and BAe Systems engineering team was recognised
with the Chairman's Silver Award for Innovation.
