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¿WHAT IS A
DIAMOND BLADE?
A
Diamond Blade is a circular
saw blade for cutting
a wide variety of materials with special cutting equipment. It consists
of a
Steel Core containing special Diamond Segments. There are several different
types of Diamond Blades: Segmented Diamond Blades, Continuous Rim
Diamond Blades, Turbo Diamond Blades (Serrated Continuous Rim),
Turbo Segmented Diamond Blades (with serrated segments).
The core of the diamond blade is made
up of precision
steel and may have several gullets (spaces between segments) depending on the
usage of the blade. These gullets allow a cooling process through air and water
circulation between the segments. They also allow the blade to bend under high
tension cutting.
The diamond segments are a mixture of diamond
crystals and metallic powders. The diamonds used in the blades are synthetic or
natural industrial diamonds of several different grain sizes, shapes or
qualities.
¿How Do DIAMOND BLADES Cut?
A diamond blade doesn't cut like a knife, it
grinds. Through the fabrication process, diamond crystals are exposed on the
surface and the sides of the segments. These exposed diamonds do all the grinding.
The bond of metal powders hold the diamonds in place throughout the cutting
process. Behind each diamond crystal, there's a "tail" (like a comet) which
helps hold the diamond crystals in place.
Through the cutting process, the
operator will push the blade through the material. The blade will begin to cut
through the material, and the material being cut will begin the wearing process
of the diamond blade, at the rate of which the blade advances.
The exposed diamond crystals will break into smaller
pieces while cutting. Harder, Dense materials will fracture the diamonds faster. As
this happens, the material being cut also wears down the metal bond through
abrasion. Highly abrasive materials will wear the bond faster, exposing new
diamond crystals to continue cutting.
¿How to Select a DIAMOND BLADE?
Before you begin.
The contractor should decide which is more important: whether it's the initial
cost of the blade or the cost per foot/meter. For smaller jobs or occasional
use, you may prefer a lower priced blade. For larger more important jobs the
cost per foot/meter is generally much more significant than the initial cost of
the blade.
Identify what
you will be cutting.
This is the single most important factor. The majority of diamond blades cut
only a specific variety of materials. For more efficiency (of cutting speed and
duration), you should be sure to select the best type of blade for your
application.
Choosing
between dry/wet cutting.
Using some equipment you may not be able to use water due to electricity. For
floor saws (walk behind) it is preferable to use water to reduce dust levels
and act as a coolant for the blade.
For high speed saws, dry cutting blades are
recommended, however sometimes water may be used to control dust levels.
While wet cutting blades and core bits must be
used ONLY with water, dry cutting blades on the other hand can be used with or
without water (depending on the job situations or the equipment).
Under
Cutting of Segment Supports
Cause.
Under cutting is a situation in which the base of the segments wear down before
the diamond segment itself. Usually right at the union of the segment & the
supporting steel core.
This condition is caused by highly
abrasive materials creating friction along the blade in a consistent pattern.
In general sand based materials are
responsible for this situation. For example: Green Concrete, Asphalt,
Prefabricated Cement (with synthetic of fractured sand), etc.
Remedy.
The distribution of the abrasive residue over a larger surface area, further
away from the critical support area beneath the segments. This is usually
achieved by using Under Cut Protection segments which are deeper than the rest
to help change the path of the abrasive slurry and distribute it over a larger &
safer area. You should also use plenty of water to eliminate the abrasive
residues.
Uneven wear of the segments
Cause.
The segments wear down on only one side, reducing the lateral tolerance. The
common cause is a badly aligned blade or the lack of sufficient water on one
side of the blade.
Remedy.
Verify the alignment of the equipment. Clean the water system making sure the
water is evenly distributed along the border of the flanges (blade supports).
Check to make sure the pump is sending enough water evenly to both sides.
Cause.
The blade is wearing down badly due to worn bearings, worn shaft, an orifice on
the blade's arbor which is bigger than the shaft of the saw, dirty/damaged
flanges or excessive blade wear.
Remedy.
Replace the bearings or the shaft. Examine the flanges to see if they are
damaged.
Cracks in the Core
Cause.
Excessive cutting pressure or jamming the blade in the cut can bend the
segments and crack them.
Remedy.
The operator must apply moderate pressure and be sure not to turn the saw while
the blade is in the cut. Try to avoid uneven surfaces when cutting.
Cause.
Overheating due to lack of coolant or inappropriate use of dry cutting blades.
Remedy.
Use the correct amount of water when using wet cutting blades (for example 2 to
5 gallons per minute on walk behind saws). For high speed saws, allow them to run
freely for about 15 seconds after a few minutes of cutting so the air can act as
a coolant.
Cause.
The metal bond of the blade is too hard for the material being cut.
Remedy.
Use a blade with a softer bond.
Segment loss
Cause.
The material
slips during the cutting which causes the blade to jam or throw a segment.
Remedy.
Make sure the material being cut is held in place correctly before cutting.
Cause.
Worn flanges aren't providing enough support which causes the blade to slip.
Remedy.
Replace both flanges.
Cause.
Overheating. Easily detected by a bluish color underneath the segments,
generally limited to the area of the lost segment.
Remedy.
Check to see if the water system is being clogged. Make sure the water pump is
working correctly. For dry cutting it may be necessary to cut lesser depths and
allow the blade to spin freely every few minutes to allow the air to cool the
blade.
Cause.
Blade is too hard for the material being cut, glazing over the diamonds which
causes a pounding on the material resulting in segment loss.
Remedy.
Use a softer bond.
Cracked Segments
Cause.
The bond is too hard for the material being cut. The hard bond retains the
diamonds which are rounded off and instead of cutting, the segments become
smooth and lose their cutting "edge".
Remedy.
Change to a softer bond which can wear down faster, allowing new diamond
crystals to be exposed to continue cutting.
Overheated blade
Cause. Lack of sufficient
coolant.
Remedy. Check the water system for clogged nozzles.
Use dry cutting blades only for superficial cuts (2-5 cm).
Cause. Continuing to cut
with a blade which no longer has useful diamond segments.
Remedy. Always check the segments when the blade is
nearly worn out. With laser welded blades there is a small laser welding pad of
approximately 1mm. For example a laser welded blade with 10mm segments has
approx. 9mm of useful segment height and should be discarded once the laser
welding pad is reached. This can avoid damage and prolong the life of the saw.
Blade will not cut
Cause.
The bond is too hard for the material being cut. The segments become smooth. (Example:
Using an asphalt blade for cutting hard Cured Concrete)
Remedy.
Consult your provider for the appropriate blade to effectively cut the material.
If the segments become smooth and no longer cut, you can re-sharpen the segments
by cutting an abrasive material such as asphalt or cinderblock until the
segments are rough once again.
Master Blade International LLC
Toll Free #:
1-888-627-4510
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