ROCKLABS December 2002...
from ROCKLABS, World
Leaders in the manufacture of Sample Preparation equipment
and Gold Assay Reference Material.
Diavik Diamonds - Mechanised
Sample Preparation System.
This System is the 14th Sample Preparation System manufactured by ROCKLABS..
Continuous Flow Ring Mills (CRMs). The Mark VII model is now available
with 3 different Options
including one with an RSD (Rotating Sample Divider).
Recommendations for all Boyd Crusher Users.
Reference Materials. 8 new values were added recently, increasing the
range to 19 values.
Barricks Goldstrike Mine in USA awards ROCKLABS new
order for Automated Sample Preparation
Systems. Rocklabs has 3 sample preparation Systems operating in the Goldstrike
in Nevada. The new order is for equipment to replace existing machines
from another manufacturer
and extend sample processing to include weighing of rotary splits into
test tubes, ready for digestion.
If you would like details of any Systems, please contact us at email@example.com.
Conferences in 2003. Three Conferences scheduled for 2003
that might be of interest to you.
Society of Mineral Analysts (USA) in April in Elko, Nevada.
Canadian Mineral Analysts in September in Ottawa, Canada.
World Conference on Sampling and Blending (in honour of Pierre Gy) in
August in Denmark.
Customer Support: Rocklabs has appointed Franky Kwok to
a newly created position of Customer
Support Engineer. Franky is a Mechanical Engineer. He will be assisting
customers on a technical
level, especially with Mechanical and Automated Systems.
Rocklabs Calendar. As a small thank you for
your support over the past few years, we enclose
our Rocklabs desktop calendar. We wish you and your families a Happy
Christmas and a prosperous
Export Sales Manager
DIAVIK MECHANISED SYSTEMS
The Diavik diamond mine in northern Canada is required to monitor its
waste rock for the
possibility that it will cause acid drainage problems in the future.
There will be 100 to 150 of
these samples to be processed in one shift, every day.
After drying, each sample is loaded into the System with
the electro-hydraulic lift (on the left
of the photograph)
Each sample is crushed finely with a Boyd Crusher and the
crushed product is fed into a
Rotary Sample Divider (RSD). The split from the RSD can be any proportion
The split % is set manually. The split portion falls into a two stage
Continuous Ring Mill
(CRM) that pulverises the sample and delivers it into a disposable plastic
cup. One sample
is prepared every three minutes.
There is no automation. All machines operate all the time.
The cabinet is sound proofed
to 80-82 dBA. The waste material falls from the cabinet into a wheeled
bin. It could be
removed outside the building on a small belt conveyor. The cabinet is
connected to the lab
dust extraction system. This simple, mechanised System could be used
by many mines.
The Continuous Ring
Mill ( CRM ) is suitable for:
- Pulverising large samples from 1 kg to 1 tonne
- Coarse pulverising of large samples for mineral separation
e.g zircon dating
- Preparing samples for on-steam analysis, dry or slurries.
The standard CRM is available in 3 Options.
- Option 1: sample flows into a 10 kg container (as shown
- Option 2: sample flows into a 500 gram plastic pottle/container
- Option 3: sample flows from the CRM into a Rotating Sample
Divider (RSD) (as shown below)
- Continuous flow through operation
- High productivity
- Large sealed, easy clean stainless steel collection bins
- Samples fed from hopper via a low maintenance variable
speed vibrating feeder
- Built-in ducting of cyclone with external vent for connection
to dust extraction system
- Automatic cleaning cycle for Options 1 and 2
- Head dismantles easily for cleaning.
- Quiet operation - less than 80 dB
- You MUST ensure that your Boyd motor is running in the
correct direction. The Mark 3 Boyd operates in the opposite
direction to the Mark 2 Boyd. For a Mark 2 Boyd: The front
jaw (the one nearest the operator) should move upwards
and away from the operator, i.e. towards the other jaw.
For a Mark 3 Boyd: The front jaw (the one nearest the operator)
should move upwards and towards the operator i.e. away
from the other jaw. If you are uncertain, please contact
us immediately as operating the crusher in the wrong direction
may lead to parts failing or low production rates.
- When looking into the crusher jaws from above, it is
not easy to see how much wear there is in the cheek plates.
If the plate wears more than 2 to 2.5 mm, pieces of sample
can fall down the groove worn in the cheek plate, without
being crushed properly. If the sample falls into a sample
bin in your Crusher, these larger pieces may be seen at
the sides of the bin. But, if the sample falls into a vibrating
feeder, taking the sample to an RSD, any larger pieces
will be mixed with the sample.
If the Boyd product is checked with a screen, the operator will see
the larger pieces on the screen and close the jaws to try and prevent
this. This will NOT prevent the larger pieces from falling down the
cheek plate groove but the production rate will decrease. Therefore
we strongly recommend that the cheek plates be lifted out and inspected
once per MONTH. If the groove in the cheek plate is more than 2.5 mm
deep, turn the cheek plate over. If the cheek plate is worn right through,
replace it IMMEDIATELY or the side plate of the crusher will get worn
and could break.
- In the Mark 3 Boyd, the jaw wear plate is held in place
by a wedge bar at the top. The wedge bar is held in place
with five caphead screws. If these screws are over-tightened,
the jaw may be over-stressed. To ensure a good fit, tighten
the screws to 20 Newton metres only and use Loctite on
- It is important that the jaws touch the rollers along
the whole roller, not just at one end. To check this, push
the jaw off the roller, put a piece of copy paper between
the jaw and the roller and crush one sample. The paper
should be crushed along the whole length. If it is not,
adjust the position of the roller with the adjustment bolt
and do the Paper Test again. Repeat until the
jaw touches the roller along its whole length.
- Most Boyd Crushers are being used to produce finely
crushed material e.g. 6 mesh, 10 mesh. For this type of
product, the jaws are normally set with a minimum gap of
about 2 mm. A small change in the gap can produce a big
change in the production rate, so check your samples carefully.
If they are being crushed finer than necessary, open the
jaws a little e.g. one sixth of a turn of the adjustment
bolts. Increasing the gap a little, increases the production
rate, decreases the stress on the crusher and increases
the life of the wear plates.
- Boyd Crushers require very little greasing, but grease
can very slowly leak from sealed bearings. The bearings
may need re-greasing. Have you ever taken your Boyd apart
and checked the bearings? Contact us for help.
PLEASE KEEP THIS
PAGE WITH YOUR BOYD MANUAL
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