Equipment Needed:
- Electric Grinder with Masonry Disc or Wire Wheel
- Rotary Hammer with 5/8", 1/2", or 3/8" bit
- Airless Sprayer with Zerk Coupler
- Screw Driver or 9/32" Nut Driver
- Prime Packers or Bang-in Ports
- Socket Wrench with 3/8" deep well socket and extension
- Flush Wand
- Vice Grips
- Hammer
- Safety Googles
- Rubber Gloves
- Long Sleeve Shirt and Pants
Materials Needed:
- Prime-Flex 900 XLV or 900 LVSF
- Prime Flush
- Prime Plug
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here to visit our page of downloadable Technical Data Sheets
and MSDS.
START WITH A VISIBLE CRACK
The surface of the crack may need to be cleaned off with a mechanical
grinder or a wire brush. Deposits left by effervescence can inhibit
full penetration of the grout.
DRILL INJECTION HOLES
Appropriate sized hole should be drilled at a 45° angle so
that it intersects the crack at roughly 1/2 the depth of the concrete.
Maximum depth required on almost any structure is 18". Hammers
with vacuum bits are not recommended.
Cracks tend to veer off in one direction or another below the
surface level. It may be necessary to stagger injection holes
from one side of the crack to the other. This will insure that
at least half of the holes intersect the crack.
Hole spacing depends on the width of the crack, but typically
is between 6" and 10" for hairline cracks. Holes may
be spaced as far apart as 24" on wider cracks. If the concrete
being sealed is 6" deep or less, holes should be drilled
directly into the crack no more than 6" apart.
On large jobs a 20' test section should be injected to determine
the most feasible and economic port spacing.
FLUSH INJECTION HOLES
A flush wand that will reach the back of the injection holes should
be used to flush out the drilling dust. USE ONLY CLEAN WATER TO
FLUSH OUT THE HOLES. It is very important to get the holes as
clean as possible, otherwise the dust will clog up the crack and
inhibit penetration of the grout.
INSTALL PORTS
Mechanical packers should be used in weak concrete or for deep
drilling. They should be inserted until the top of the rubber
sleeve is flush with concrete. If the rubber is not flush with
the concrete it may either spall the concrete when tightened down
or blow out when the injection pressures start to rise. Use a
3/8" deep well socket to tighten the Packers.
The tips should be left off of all the Packers until you are
ready to flush the crack. Bang-in ports are an excellent choice
for good concrete where deep drilling is not necessary. Simply
bang them into a 3/8" hole with a hammer.
FLUSH THE CRACK
Install a tip on the first packer. USE ONLY CLEAN WATER TO FLUSH
THE CRACK! Injection pressure should start at 250 p.s.i. and be
increased as needed. This will clean dirt and other contaminants
out, open the crack up, and insure that enough water is present
to activate the grout. A non-staining dye may be added to the
water to see where the flush water is coming out and to help separate
ground water from flush water.
Start flushing with the injector that is at the bottom of a vertical
crack, or at the very end of a crack if it is horizontal. Continue
to flush with water until only contaminate free water is flowing
out of the crack or the next port. If no water is being pumped
through the port, the injection hole may not be intersecting the
crack. If this is the case, drill another hole on the other side
of the crack and repeat the above steps. Be sure not to cross
through the first injection hole. Repeat this process for every
port.
NOTE: The rubber in the Mechanical Packer tends
to relax if left in the wall for more than eight hours. This causes
the Packer to become loose and may cause blow outs when high pressure
is used to inject the grout. To avoid this, the Packers may need
to be re-tightened prior to grout injection.
In order to insure that the grout will not set up in the pump
and hoses, it is best to use two different pumps - one for flushing
and one for grout injection. If this is not possible, be sure
to thoroughly flush the pump out with Prime Flush non-flammable
solvent before switching from water to grout.
Prime-Flex and 900 LVSF and 900 XLV are the best materials on
the market for injecting into hairline cracks.
INJECT THE GROUT
Always wear safety glasses, rubber gloves, and long sleeve shirt
and pants when doing any type of pressure injection. See MSDS
sheet before working with any Prime-Flex products.
Remove the tips from all of the ports. Re-tighten the Mechanical
Packers if necessary. Put a tip on the first Port used to flush
and begin injecting Prime-Flex. Patience is a must when doing
crack injection. It may take several minutes to get resin flowing
into the crack. Increase pressure in 100 p.s.i. increments as
necessary. The lowest pressure that will get penetration should
always be used, but it may be necessary to increase the pressure
as high as 2,500 p.s.i. Be very careful when turning the pressures
up this high, as the concrete may shear or the Packer can blow
out of the hole. This usually results in the technician being
sprayed with grout . If grout begins to flow freely from the crack,
stop injection to give the material time to activate. The crack
should seal enough to begin injection again within a few minutes.
If the flow does not stop, Prime Plug (rapid setting hydraulic
cement) may be necessary to plug the leak. Clean the grout off
of the crack as much as possible before applying Prime Plug. It
will set within a few minutes.
NOTE: It is useful for a small amount of grout
to drip out of the crack. It allows the technician to see how
far the grout has traveled and it will seal itself up within a
few minutes.
Continue to pump until material has penetrated the entire distance
between the first and second Packer. The grout will not always
visibly travel the entire distance in hairline cracks. Once the
furthest point of grout travel has been obtained, move on to the
next Packer and repeat the process.
FLUSH THE PUMP
When finished pumping for the day, the pump should be thoroughly
flushed out using Prime Flush solvent. Material left in the pump
overnight may set up and ruin the pump.
REMOVE THE PORTS
Wait 24 hours before removing the ports. If it is necessary to
remove them the same day, a small amount of water may be injected
into each hole before removing. Usually a 3/8" socket and
wrench, vice grips, and a small screwdriver are necessary to remove
the Mechanical Packers. Bang in ports are removed with vice grips.
PATCH INJECTION HOLES
The injection holes should be patched with an epoxy gel (Speed
Bond #1).
GRIND GROUT OFF SURFACE
Use an electric grinder with a grinding disc or a wire wheel to
remove the grout from the surface. Use caution; a wire wheel can
"grab" the grout and be pulled from the technician’s
hands. If possible, wait 24 hours before grinding.
APPLY SURFACE SEAL
Apply a band of Prime Gel 2200 Flexible to the surface of the
crack to give a more attractive look to the surface and to act
as a secondary barrier.
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