(For new construction and rehabilitation)
Square or Rectangular
1. Remove existing casting and rings or cover plate to expose concrete structure.
2. Stretch string line or position straightedge to determine height adjustment required.
3. Combine various ring heights, in both flat and slope, to reach desired adjustment. Rings are to be placed with pocket openings down and tabs extending into structure or lower rings. Note: Slope rings are tapered from side to side at an angle to prove a 1% to 3% grade compensation.
4. If offset of rings is needed to achieve casting-to-curb alignment, use a saw to remove interlocking tabs from underside of ring(s) as necessary. Removal of tabs from one side of end of ring will allow up to 2 “ of offset. Offset should not exceed this amount per ring. Removal of tabs from more than one side will allow for rotation of the rings. Note: Total offset of all rings should not exceed 4” without a concrete collar being poured to maintain stability and integrity of structure.
5. If the specifying engineer requires a woven, unwoven or poly fabric wrap, it should be applied at this time. If used, the wrap should extend over casting flange and a minimum of 4” below top edge of concrete structure. If oversize manhole with top slab, wrap should rest a minimum of 6” out from rings and on top of slab.
6. Place castings on ring(s).
7. Backfill around structure.
Pour concrete collar around structure if required by specifying engineer.
Special Instructions for other adjustments:
1. Should offset of rings on structure be required, a portion of the interlocking lip of the first Rings may be cut off. Offset should not exceed 2” per ring. Total offset should not exceed 4” without a concrete collar being poured to maintain stability and integrity of structure.
FURTHER QUESTIONS ?
CONTACT YOUR LADTECH DISTRIBUTOR OR :
Dwight Wiedrich at 612-860-0806
Optional - Installation Instructions
Ladtech® HDPE Adjustment Rings
All Round Manhole Adjustment Rings
Hinged Manhole Frames
For New Construction, and Rehabilitation
All Weather Sealing Instructions
Vacuum Testing Sealing Instructions
Installation should be preformed by competent professionals, trained in all safety aspects related to a typical manhole chimney section, and casting installation. As actual installation is out of our control, we assume no responsibility for results. This is only a guide; do to the wide variety of actual site conditions this may vary from site to site.
1. Full selection of Ladtech® HDPE adjustment rings including slope rings, 1.25”, 1.50”, 2”, and 4” of the correct diameter to fit your casting.
2. Manhole frame and cover.
3. Key hole saw.
4. Small hand saw.
5. Straight edge, or string.
6. Tape measure.
7. Clean rags.
8. 3/8” butyl rubber rope. (for vacuum tested installations only)
9. Tapecoat® Omniprime® (optional)
Remove casting and chimney section to top of manhole. Leave a minimum of 6” of clearance around new Ladtech® rings. Remove debris, and clean surface.
Ladtech® HDPE adjustment rings are an engineered product that require a relatively flat surface for proper support. Missing bricks, or an otherwise damaged, or a poorly made cone need to be repaired to a flat surface. Quick set mortar works well for this, and should be done prior to installation.
Ladtech® rings feature a pilot on the down side of the ring to align, and stabilize the rings. If the manhole opening is undersized the pilot may have to be trimmed. Using a small hand saw remove only enough pilot to allow the ring to set into the opening.
The pilot always is installed down into the opening of the manhole.
Measuring Ladtech® Stack Assembly:
A temporary ring or rings that equal the frame height may be placed into the manhole to provide a good surface to measure from. This makes measurements less confusing as all measurements are the actual stack requirement. This temporary ring or rings will be removed upon final installation. A straight edge or string should be place across road surface opening in two directions. Measure down to temporary ring, and determine the slope, in four locations. Each slope ring provides .75” of slope, and measure .75” on the thin side and 1.50” on the thick side. Each slope ring will equal 2% grade, with 2 rings you can adjust from 0% to 4% grade by rotating rings. Add additional rings as necessary to obtain the slope required. Adjust both caster and camber until surface is level with the road surface.
Final Stack Assembly:
Using Ladtech® stack chart, determined the combination of Ladtech® rings that will be required to obtain the final grade minus .25”. In areas with snow plows we recommend keeping the frame and cover .50 inches low to prevent contact of the plow with the manhole cover. The chart gives all combinations in ¼” increments up to 18”. A full selection of rings is required to archive all combinations. Set required rings on top of slope rings, and do a final check with straight edge or string. Match Mark inside of Ladtech® stack with white paint. If using a hinged manhole cover you should now consider the orientation of the lid to the roadway. Consider maintenance access, steps, and any other consideration when determining the orientation of the cover. Match mark to road surface where hinge is to be located. Remove entire stack, and eliminate temporary ring, or rings used for measuring purposes. The casting frame will now replace them. Warning: never use shims to adjust Ladtech® HDPE rings. Always use slope rings. Damage, and failure can result do to improper shimming to obtain grade.
Clean Out Notch, (Hinged Castings Only):
After removing the entire stack from manhole the top Ladtech® ring should be notched for a clean out area if using hinged castings, with blocking mechanism. Refer to installation C.D. for photo detail of notch area.
Chimney Section Sealing.:
Sealing of the chimney section may or may not be required depending on application. Installations for storm water may not need sealing. We do recommend that on these applications the locking collar be poured to the surface of the manhole to prevent backfill from washing through which may cause a sink area around the manhole. If the chimney section is to be vacuum tested additional sealing may be required.
Ladtech® sealing instructions:
All weather stack installation sealing: (non vacuum tested)
Place sealed stack of Ladtech® rings, and casting frame, next to manhole. Make sure top of manhole is clean and free of dust, dirt, and debris. Water may be used to wash top of manhole opening. SealGuard® L.R. is designed specifically for installing and sealing Ladtech® HDPE rings in all weather conditions, and will work in wet or dry conditions, and in most ambient temperature ranges. SealGuard® L.R. is a two component urethane expanding foam that is applied using either a manual plural component gun, or a pneumatic plural component gun. Place a new static mixer on cartridge, and install in gun. Use approximately 2/3 of cartridge around top of manhole opening, and quickly set Ladtech® stack into hole (pilot down) making sure to line up match marks if required. Evenly apply the remaining SealGuard® L.R. to the top of Ladtech® Stack, making sure that there are no gaps in the coverage. Always use rubber gloves which may be used to quickly spread grout if necessary. Quickly set casting frame matching hinge box to clean out on Ladtech® stack. SealGuard® L.R. will kick off and expand at a 20 to 1 ratio in about 1 minute @ 70° F. You must work quickly when assembling stack, and have stack in place before the grout kicks off. In hot weather, placing the SealGuard® L.R. cartridges in cold water will give you more working time.
(Note SealGuard® L.R. properly installed will give you a water tight installation, however SealGuard® L.R. is not air tight. Vacuum tested chimney sections will require additional sealing.)
Vacuum tested chimney sealing:
Assemble chimney as outlined above using LadSeal® waterproofing tape. Apply Butyl Rubber Rope to a clean, dry, surface, around opening of manhole. In below freezing temperatures the use of Tapecoat® Omniprime® primer applied to the concrete is recommended. Apply primer in a thin coat, and allow to dry to touch. Butyl rope is available in 3/8” to 1” diameter to accommodate irregularities on the manhole surface. If possible apply an additional wrap of LadSeal® waterproofing tape around circumference of base to top of manhole. Surface must be clean and dry. Apply 3/8 butyl rubber rope around top of Ladtech® stack, and set casting frame. Weight may be required to compress butyl rubber rope. (Backhoe bucket works well)
Hole may be partially back-filled, and compacted. A locking concrete, or epoxy bedding compound collar is recommended. Collar should be a minimum of 8” thick, and extend at least 2’ up on frame. Asphalt or pour collar to grade. Concrete collars poured to grade may be dyed black to match surrounding pavement.
Protect your manhole:
Protect the hinge area, and handling openings from asphalt by covering with sand, or using duct tape. Contractors should be responsible for any clean up of lids do to failure to protect the cover from asphalt.
Frames that need to be raised that have been installed using Ladtech® rings, and LadSeal® tape should be excavated being careful not to contact rings with jack hammer. Brake out old locking collar, remove debris. Locate a seam between two Ladtech® rings. Insert thin blade utility knife between Ladtech® rings, and cut around circumference. Lift out frame with Ladtech® ring attached. Install required Ladtech® ring to obtain correct stack height. Set frame on stack and seal with additional wrap of LadSeal® tape. Pour new collar.