|
EXTERNAL ROTARY
Introduction
The External Rotary is when the milking
operators are on the outside of the rotating platform, one to put
cups on and and a second person to remove the cup clusters. The cows
face inwards and learn to step backwards and turn out of out of the
rotary bail after being milked.
See
Rotary Systems page for a general description of
both external and internal rotary systems.
Key benefits of the External Rotary are:
Dairy Tech's design has distinctive standout
features, as described below:
Quick notes:
-
Bail angle allows higher percentage of cows
on the available platform area;
-
allows for easy cupping;
-
allows for easy cow flow in and off
platform;
-
quiet operation due to concrete platform on
nylon rollers;
-
strength and durability - concrete over
steel.
Deck
The
platform of 40MPA (industrial strength) concrete averages 100mm
thick and its construction and shape make it extremely strong. It is
broom finished to provide a non-slip surface and shaped so that an
outwards slope takes water and waste away from the operator and
allows for easier cleaning. The platform is engineered and poured on
top of boxing sheets in situ (in place).
Bails
The
bails are made of hot-dip galvanised steel pipe, as are the RHS
steel posts also manufactured by Dairy Tech. The angle of the bails
relative to the platform allows for a higher percentage of cows on
the available platform area. An overhead bail wash system is part of
the standard set-up .
Pipework
The
inside circumference of the external platform has a fixed head and breast galvanised rail supported from the
platform while the bum rail is supported from the roof, and in
larger dairies supported from the floor as well.
Support for
platform
Nylon
rollers especially manufactured to Dairy Tech specifications allow
for high impact forces ... quietly. The support mechanism is guarded
by a stainless steel skirt for operator safety and for plant
cleanliness.
Platform Rotation
Rotation is set clockwise or anticlockwise to suit the building site
and required cow flow. The platform drive unit is provided by one to
three electric motors depending on platform size. A dual or
triple motor system offers back-up to keep the platform operating
should a single motor fail.
Access
Access
for the operator wanting go to the centre of the platform can be
simplified by including an under-platform walkway, as required for
filling meal bins, using the drench platform and for plant and
platform maintenance. Access otherwise is by walking between the
bails and across the platform. Cups on and off stations are on the
outside of the rotary platform.
The
cows’ access to a bail is by walking a few steps over a bail-width
concrete span from the dairy yard to the platform. They walk in
front-on and exit by backing and turning in the direction encouraged
by bail design for heading towards the exit. Bail exits are wider to
allow the slight turn.
Safety
An
emergency stop cord runs around the perimeter level with operator
head height. Dairy
Tech adheres rigidly to OSH requirements such as the gap tolerance
between the bail and perimeter rail and other structure clearances.
Dairy Tech has made industry representations and consulted in detail with OSH to
ensure workable regulations and guidelines that effectively
provide for a safe environment for dairy operators, visitors and
livestock.
Console
A
stainless steel waterproof console for the cups-on operator has platform forward, stop and
reverse buttons, a speed control button, drafting gate buttons and
automation options when fitted. A second, simplified console is for
the cups-off operator.
Gate entry and exit
Dairy
Tech designed the twice-round arm the can be pneumatically raised
and lowered to keep a cow on the platform for a repeat round. Both
operators control gates from their separate consoles.
Options
Automatic cup removers, individual animal ID electronic tag or
collar reader, leg spreaders, access gallery, drench systems,
cup wash sprays and additional water points, teat spray systems at
exit race and other efficiency aids are available. Additional
options for the external rotary are an AB table, meal bins and meal
feeders.
UPGRADES - EXTERNAL
Common reasons to upgrade are:
-
to install a larger platform for a bigger
herd;
-
to save on the cost of replacing the whole
dairy;
-
to replace a platform at the end of its
economic life.
But upgrade options do
depend on existing facilities, such as whether the dairy building is
big enough in area - and in in many older external rotaries the
building is too small for a bigger platform setup.
In fact, the upgrade
of an external rotary is usually less cost effective than for an
internal rotary upgrade.
One limitation for the
external rotary is the usual requirement for a new bridge from the
yard on to the platform. Another restriction is the lack of space
for realignment of bails.
Whatever the issue to
be solved, an upgrade decision is best made with information and
advice from Dairy Tech, which offers a platform design allowing more
bails than other rotaries of similar size, as well as reliability
and a maintenance service.
Dairy Tech upgrades usually extend to the whole
dairy system, including drive motors, milking machinery and plant
without being tied to any brand.
Automation is also an option if new cables can
be run through the existing dairy.
Back to top of page |
