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Application Rig

Damaged Manhole  (above & below)

This figure shows the completed manhole.

This figure shows the completed manhole.

As has been reported in numerous articles, newspapers, and trade journals, the United States waste water infrastructure is old, deteriorating, and over-taxed.  New construction continues, but as existing utilities age, replacement or repair becomes a necessity and millions of dollars have been committed by federal state and local utilities for repair. Manholes are an integral part of the waste water system, and typically are prone to deterioration by water infiltration and surrounding ground movement.  A fast and easy repair is available which provides renewed structural strength and chemical resistance to a manhole.  A unique polyurea/epoxy system, developed by Polyurea Coating Systems, Inc., is in use in many utility districts around the country.  PCS-30 and PCS-355 are applied in a two stage process which eliminates the need for plastic liners or replacement of the damaged brick or concrete.  This case study was made on a recent rehab of a series of brick lined manholes in Quail Valley, Texas.  Kenny Industrial Services, LLC was the applicator on the site.  PCSI supplied the PCS-40 primer and PCS-355 polyurea as a system to the project.

Prior to beginning the project, Kenny Industrial obtained the location of each manhole and mapped a plan to repair each in an efficient manner, utilizing manpower and equipment to the maximum extent.  Quail Valley is a sprawling subdivision with parks, common facilities and golf courses.  Each manhole was constructed with a brick chimney approximately 3 feet deep.  Kenny Industrial uses a transport truck to move the spray apparatus, equipment, materials and a 3 man crew to each man-hole site.  The above photo shows the equipment truck spray hose and safety equipment.

The process for each manhole was identical.  The crew used the late afternoon and early evening hours to clean each manhole with a high pressure water blast.  This removed the dirt, debris and loose or broken surface.  The brick was then coated with PCS-30 penetrating primer to a thickness of 2-3 mils.  PCS-30 is a 100% solids epoxy eliminating the need for special solvent handling precautions.   The penetrating primer was allowed to cure overnight. The  photos below show the manhole before cleaning.

The following morning, the crew arrived at the prepared and primed manhole and applied PCS-355 with a plural component heated spray rig designed to handle polyurea.  One member of the crew removed the manhole cover, the next positioned the spray hose and gun, while the third donned the required protective clothing.  The manhole was then sprayed with PCS-355 to a thickness of between 80 and 100 mils, depending on the condition of the brick surface.

In this case, physical entry into the manhole was not required as the spray technician could reach the entire surface by inserting his arm into the manhole.

 However, as shown in these photos, the spray technician was equipped with an air supplied mask and was secured with a safety harness during application.  The entire application of the polyurea  took between 5 and 10 minutes, before moving to another location.  The PCS-355 was ready for service immediately after closing the lid.  This is an added benefit in a part of the country where thunderstorms are frequent and unannounced.  In this manner, 5-8 manholes could be rehabilitated each day, depending on the distance between each site.

The PCS-30/PCS-355 system has excellent adhesion to the brick and concrete, provides an impermeable elastic membrane, which supports the brick chimney.  The polyurea was provided in white, which adds light to the manhole for future work.  The elasticity of the membrane allows for considerable movement of the structure without damage to the membrane.

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