Award Bid - 2024 Sewer and Manhole Rehabilitation Proj No. 122-019 - Visu-Sewer, LLC

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RECOMMENDED INSTALLATION PROCEDURES The following installation recommendations are a set of installation options that have been used successfully to install cured-in-place pipe. In most cases the installation practices described below may have a considerable factor of safety built into the procedure. There are clearly many other possible variations of these described practices that may be more effective and/or efficient for installing a cured-in-place pipe. However, it is strongly recommended that inexperienced installers follow the guidelines outlined below or the guidelines personally conveyed by experienced personnel in order to avoid unnecessary problems during the installation of the cured-in-place pipe. As these techniques are reviewed, they may be added into this procedural document as improvements to the system. LAY FLAT HOSE & HOLD BACK ROPE Materials -- The circulation hose system necessary to properly circulate water for curing a tube should be made up of three different types of hose materials. The out flowing water hose, going from the heater to the layflat hose, should be a heavy duty hose capable of handling at least 100 psi at 212 degree F. This hose should be a semi-rigid material that can withstand the bending and twisting it will experience. The high temperature hose then should be connected to reinforced blue PVC (Layflat) hose rated for 50 psi. This hose works well at high temperatures as long as it is not kinked or stretched and should therefore be measured so that it only extends within the pipe or liner itself. In general, both types of hose material should be the same diameter and be connected by a spliced joint or hose mender. The third type of hose material is the suction hose, which returns the water from the water column back to the water heater. This hose must be rigid (but flexible) and capable of withstanding internal vacuum forces at elevated temperatures of 212ºF. It is recommended that the suction hose should meet or exceed the following specifications: Black EPDM tube and cover, multiple textile plies with helix wire, and a temperature range of -30ºF to 300ºF. The hold back rope ideally should be a stable braid polyester low stretch rope suitable for high temperature use. For liners up to 36 inches in diameter, the rope may be 0.625 inch. For larger diameter pipe, the rope should be at least 1 inch in diameter. Lay Flat Configuration & Measurement -- The lay flat or circulation hose preparation and measurement is one of many critical steps in materials preparations for installing a tube. The length of blue lay flat hose should be estimated by adding the center-to-center measurement of the line plus the column height plus an additional 10-20 feet and subtracting 5 feet for the turn- back on the liner to ensure the length is adequate. The heavy-duty high temperature hose length should be determined by adding 10 feet to twice the length of the column and any additional distance necessary to connect to the water heater. Lay Flat Hose Splicing -- Each lining section should have a maximum of three splices per lining segment. Old, worn and stretched circulation hose should be discarded and replaced with new or undamaged hose. Damaged hose and/or too many splices may result in poor circulation or may separate during the installation procedure. Although service and installation conditions vary, typical PVC based blue lay flat discharge hose can be used for quite a number of installations before it must be replaced. Splicing hoses together is an easy procedure, but the direction of the splice is critical for proper circulation.