EQUIPMENT NEEDED
1. Electric Grinder with Masonry Disc or Wire Wheel
2. Rotary Hammer with 5/8", 1/2", or 3/8" bit
3. Airless Sprayer With Zerk Coupler
4. Screw Driver or ¼" Nut Driver
5. Prime Packers or Bang in Ports
6. Socket Wrench with 7/16" deep well socket and extensio
7. Flush Wand
8. Vice Grips
9. Hammer
10. Safety Goggles
11. Rubber Gloves
12. Long Sleeve Shirt & Pants
MATERIALS NEEDED
1. Prime-Flex 900 LV or 900 LVSF
2. Prime Flush
3. Prime Plug 10
START WITH A CLEAN CRACK
Clean the surface of the crack. All loose or unsound material must be removed.
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. 18 inches is the maximum depth required on almost any structure. Prime-Resins recommends the use of a heavy duty rotary hammer. Cracks tend to veer off in one direction or another below the surface level. For this reason 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 your 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" or more on wide cracks.
If the concrete being sealed is 6" deep or less, holes should be drilled directly into the crack 4" deep 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. Make sure to get the holes as clean as possible to insure penetration of the grout.
INSTALL PORTS
Mechanical packers should be used in weak concrete or for deep drilling. Insert 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 7/16" 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 range start at 250 p.s.i. and increase 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 separate ground water from flush water.
Start flushing with the injector that is at the bottom of a vertical crack, or at the tightest end of a horizontal crack. Continue to flush with water until only contaminate free water is flowing out of the crack or the next Packer. If no water is being pumped through the Packer, it is probably because the injection hole does not intersecting the crack (this is a dead hole). 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 which 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.
APPLY THE SURFACE SEAL
A surface seal(Prime Plug) must be applied in order to contain the grout within a wide crack(make sure crack is clean).If the crack is extremely wide, the Activated Oakum technique may be used (see Activated Oakum Technique).
If water is gushing out of the crack, remove the tips from the Packers. They will act as a vent to reduce the water pressure on the crack making it easier to apply the surface seal.
INJECT THE GROUT
Please see MSDS sheet before working with any Prime-Flex products. Always wear safety glasses, rubber gloves, and long sleeve shirts and pants when doing any type of pressure 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 cleaning solvent before switching from water to grout.
Grout may be injected as a single component or two components. For two component injection, a two component pump with a static mixing chamber at the end of the hoses may be used. Prime-Flex products can be mixed at a 1:1 or 2:1 ratio of grout to water. The mix ratio has only a slight effect on cured properties of grout.
Prime-Flex 900LV and 900 LVSF are the best materials on the market for injecting into wide cracks.
Leave the tips off of all the Ports that have not had grout injected through them. They will allow air and water to vent out of the crack. Failure to do this will result in excess pressure building up in the crack and possibly cause further damage to the structure.
Remove the tips from all of the Ports. Re-tighten the 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. If you are not careful, the concrete may shear or the Port may blow out of the hole. This usually results in the technician being sprayed with grout.
If the surface seal blows out and grout begins to flow freely from the crack, stop injection to give the material time to activate. It should be able to seal the crack enough to begin injection again within a few minutes. If the flow does not stop, Prime Plug 10 may be necessary to re-plug the leak. Clean the grout off of the crack as much as possible before applying the Prime Plug 10. It should 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 should begin to flow out of the second Port. Once the furthest point of grout travel has been obtained, move on to the next Port and repeat the process.
FLUSH THE PUMP
At the end of the day, the pump should be thoroughly flushed out using Prime Flush. Grout left in the pump overnight may set up and ruin the pump.
REMOVE THE PACKERS
It is usually best to wait 24 hours before removing the Ports. If it is necessary to remove the Ports the same day, a small amount of water may be injected into each hole before removing. Usually a 7/16" 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 to a depth of one inch 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 technicians hands.
