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

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• Seal the fourth side of the sleeve. • Place the appropriate spacers in the mold forming a trough for the sleeve to be placed into. Prior to placing the sleeve into the mold, roll any excess plastic up on one side so that excess resin in the felt can squeeze into this avail able space. Take care to use the proper spacers for the thickness of liner installed. • Put the second plate in place and tighten down carefully. If it appears that the sleeve may burst due to excess resin, back off and readjust the felt in the sleeve. However, it is critical that the felt layers are compressed tightly between the two plates because any delamination between adjacent layers of felt will severely reduce the physical properties of the sample. • A rope is attached to the plate so it can be lowered into the water column and cured with the same thermal cycle as that of the CIPP. • After curing, remove the CIPP sample from the plate. Take care in the removal of the CIPP as not to damage the CIPP. Excessive force in removal of the CIPP may cause damage to the CIPP sample (cracks, gouges, etc). Samples should be thoroughly inspected for thickness, damage, or any abnormalities before forwarding on to clients and/or testing facilities. If damaged areas exist next to acceptable areas, clearly mark the specimen where it should be tested. NOTE: Do not try to remove the CIPP sample with excessive force (i.e., Throwing CIPP/Plate on the floor). If the CIPP sample will not release from the plate, it is recommended to use a small screwdriver and a hammer. Place the edge of the screwdriver between the CIPP and plate and tap gently until the CIPP sample releases from the plate. Alternately, if it is not possible to cut a portion of saturated felt from the liner, then similar felt may be saturated with the resin used in the installation and this may be placed in the clamped mold assembly. RESTRAINED SAMPLING TECHNIQUE If the client requires a sample cut from the installed liner, the best results are obtained by restraining the CIPP outside the pipe so it can easily be removed for evaluation. Due to the difficulty in restraining larger diameter CIPP (i.e. greater than 18 inches), this technique is limited in its utility for sampling CIPP. Always avoid sampling unrestrained CIPP because the tube may be thinner and lower densities because it often stretches out beyond the diameter of the host pipe and will usually have poorer cure because of no heat retention. If the CIPP cannot be restrained then make provisions to produce a plate molded sample. A restrained CIPP sample is best accomplished in the following manner: • Prepare a piece of thin walled PVC, preferably C-900, of proper diameter and length to accommodate the specified size versus thickness requirements given previously. Coat the inner surface of the PVC pipe with a liberal mold release (i.e., PVA) so the CIPP can easily be removed.