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TypeBoth
nameRehabilitating Pressure Pipe with Complex Geometry: It’s Not as Difficult as You Think
Speaker 1Jimmy Stewart
speaker1_emailEmail hidden; Javascript is required.
speaker1_phone(334) 750-3208
speaker1_repCPM Pipelines
speaker1_bio

Industry Experience
Jimmy has 25 years’ experience working in over 30 consent order driven cities.
Jimmy has been Involved in the full-service environmental inspection, technical water/wastewater evaluation, rehabilitation for water, wastewater, and storm water systems. asset management and proven cutting edge digital solutions.
Currently providing:
Pressure Pipe (Water and Wastewater) Inspections, Rehabilitation, Asset Management and Digital Solutions for utilities and engineers.
Affiliations:
• WEF Collection System Committee Chair- Current
• BAMI-I Board Member- Current
• Vice Chair Southeast Society of Trenchless Technology-Current
• Past NASSCO Board Member

Awards:
• Recipient of WEF and WEF Member associations Golden Manholes and 5S Society awards

Abstract Text

Rehabilitating infrastructure in the water and wastewater space has become commonplace for a multitude of reasons; economic efficiency, reduced environmental impact, reduced social impact, and to extend the life of depreciated assets. However, there is a sub-sector of pipe that continues to present challenges to owners and consultants alike. Water transmission mains and force mains with complex geometry continues to be replaced despite the dramatic cost savings often associated with proven, innovative technologies.

 

To understand this phenomenon, we must first look at the most-widely used method of rehabilitating water and sewer pipe: Cure-in-place pipe (CIPP). CIPP is an extremely effective method of rehabilitating pipe. CIPP materials typically form a seamless mold to the host pipe. This is not always the case in pressure pipe with complex geometry e.g., multiple 90° or 45° bends. Whether inverted or pull-in-place, the liner cannot achieve 100% coverage as it is navigated through bends because it “folds” over on itself. When the liner folds over on itself the structural integrity is diminished. In addition, this leaves segments of pipe where the CIPP materials are not properly bonded to the pipe creating an annular space between the liner and the host pipe. It is for this reason that most CIPP companies shy away from lining pressure pipe in these applications or if they do, they will request relief from the pressure test.

 

In 2013, an Flexible fabric reinforced pipe (FFRP) system was introduced to the water, wastewater and industrial markets in the United States. There are several manufacturers of the FFRP systems currently available on the market today. All are made up of a polyester and/ or Kevlar weave and appropriate jacket and liner based on design. The hoop strength is derived from the tightness of the weave and can be designed to meet various pressure requirements.

 

The advantage of the FFRP in pressure pipe with complex pipe geometry is that installs in the pipe without the need of hot water, UV, steam, or other means to cure the pipe. Rather than curing as is common with CIPP, FFRP is installed in the exact form as it is shipped from the manufacturer. Once the pipe is cleaned, cleared of obstructions and any sharp edges, a tag line is pulled in place and the FFRP is simply pulled into position with a winch. This allows for installations through complex geometries such as multiple 45° vertical or horizontal offsets.

 

Other advantages of FFRP include: economics, smaller footprint, pull lengths of up to 8,500 feet. Each of these advantages will be explored in depth as well as the products that are currently on the market. In closing, case studies will be reviewed demonstrating how FFRP has been effectively deployed throughout the US and showcase lining pressure pipe with complex geometries. It’s not as difficult as you think.