it is normal to define dynamic balance
limits to ISO 1940 and it is recommended
that the limits defined in the specification
be examined in terms of their example
applications. We would normally propose
a Q6.3 Balance for general purpose
applications and a Q25 Balance for high
speed machinery (Q1.0 on very high
speed / sensitive machines ). However, the
level of balance required is best
understood by the manufacturers of the
driving or driven machinery and, as such,
we will normally work to their
requirements.
APl671 defines a considerably tighter
limit of unbalance of 6350W/N gmm (W
being the mass and N the duty speed).
This closely related to what would be an
ISO grade of Q0.6! Bibby Turboflex can,
again, achieve this level of balance and
the related 'repeat' balance requirements
but would emphasise the lower level 'cut-
off' for very low mass /high speed units
at 7.2gmm
In summary, Bibby Turboflex disc
couplings can be supplied to meet any
likely balance requirements.
More details and procedured for
balancing any disc coupling are available
upon request.
Hub fitment
Hubs installed with a standard level of
interference may be heated for fitting.
Heat must be applied evenly, ideally using
an oil bath, to a maximum temperature
of 200°C. Careful use of torch,
continously moving over the whole
surface, is also acceptable.
Hubs installed using hydraulic expansion
normally require to be produced in high
strength alloy steel. This is standard in the
HS range but must be considered as an
option for the other ranges.
Whilst it is usual for the related machinery manufacturer to use his own
equipment for fitting the hub, Bibby
equipment in conjunction with the
couplings.
Bibby Turboflex aer familiar with most
other forms of hub fitting techniques,
including splines, shaft clamp systems, etc,
Please consult our staff for any details.
