External Wrapping of Steel Riser Pipe. Case Study HJ3 CS200902

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1 External Wrapping of Steel Riser Pipe Case Study HJ3 CS Introduction Refineries process a wide variety of petroleum products. As part of the process, they rely on cooling towers, which recycle water throughout the plant. Twelve of the Steel Riser Pipes showed signs of below grade water leakage and in response the refinery scheduled an engineering survey to determine the cause of the problem. Problem The engineering survey showed that a high percentage of steel on the pipes had corroded resulting in pitted areas and ultimately water leakage. The pipes were ¾ -inch thick. Given the extent of the damage, several solutions were considered including: replacement, welded steel, and HJ3 Carbon Composite System. The Project Engineers specified HJ3 s Carbon Composite System because it offered savings of 50% to 75% over alternative methods and 400 psi strengthening to the existing pipe. In addition, the system could be installed within 5 to 7 days with no resulting down time. Installation The steel riser pipes were first excavated to a depth of 10 feet and the mortar surrounding the pipes was removed to access the steel surface. An abrasive blast was performed to clean the pipe to a white metal finish with a 3 mil profile. After surface preparation, 2 layers of HJ3 CF528 carbon fabric were saturated and applied to the damaged pipe area. Conclusion In total, 12 steel riser pipes were repaired and strengthened with the HJ3 Pipe Repair System. The total installation was completed over 7days and resulted in 50% cost savings for the client over Steel Clamp Repairs or Replacement. The main advantages of the HJ3 Carbon Composite System were as follows: 10 x Tensile Strength of Steel Corrosion Resistant Installed in the presence of moisture Impermeable to Pressurized Water Speed of Installation 50% to 75% Cost Savings over Alternatives Including Replacement Copyright, March HJ3 Composite Technologies, LLC. All Rights Reserved

2 TM TM Composite Technologies The Strongest Name in Carbon Fiber PIPE REPAIR CONCRETE, STEEL & CLAY Advantages 10 ft Diameter PCCP Repaired using HJ3 CF516 Carbon Fiber 5 to 10 times stronger than steel Weighs 4 ounces per square foot Corrosion Resistant Chemical Resistant to Acidic & Alkali Environments Minimizes Downtime 30% to 40% Cost Savings over alternative repairs or replacement!

3 STEEL PIPE Corrosion of steel reduces pipe strength and service life. Traditionally, owners are forced to replace the damaged pipe, requiring extensive downtime, the use of heavy equipment and excavation. HJ3 Composite Systems structurally repair damaged pipe. Installed internally or externally, HJ3 Composite Systems return the pipe to its original design strength without costly downtime, heavy equipment or excavation. HOW IT WORKS HJ3 Composite Systems are reinforced with high tensile strength fibers. When these fibers are bonded to the circumference of the pipe they resist the internal hoop stress from the pipe operating pressure. The cured HJ3 Composite System also protects the pipe from further corrosion and impact. PCCP & RCP HJ3 Composite Systems are excellent repair solutions for damaged pipes below grade with limited access and can be used to repair Pre-stressed Concrete Cylinder Pipe and Reinforced Concrete Pipe. In both PCCP & RCP repair appliations the carbon fiber replaces the tensile strength lost by corrosion of the existing steel pre-stressing wires or steel rebar. HOW IT WORKS HJ3 Composite Systems can be installed on the internal or external face of the pipe to create proper tensile reinforcement necessary to repair cracks, increase flexural and sheer capacity, and proivde a waterproofing membrane to the internal pipe surface. HJ3 Composite Systems can also be used to increase the compressive strenth of pipe to overcome loads such as soil and mobile equipment. HJ3 Quikfix STOPS LEAKS HJ3 Composite Systems are now available in easy to use kits. These kits provide carbon or glass materials that are 2-inches to 10-inches wide. The carbon or glass fabrics are pre-impregnated with a water activated urethane and vacuum packaged. To install the urethane carbon or glass systems simply dip the rolls in water for 30 seconds, wrap the pipe and allow the system to cure for 30 minutes. The carbon or glass fabrics can also be packaged in 5 gallon buckets with the traditional HJ3 resins, mixing tools and application tools necessary to install the wet lay up systems. HOW IT WORKS The Quikfix repair systems are perfect for repair of small diameter pipe, pipe joints and riser pipes. Copyright 2008 HJ3 Composite Technologies, LLC. All Rights Reserved. All trademarks are the property of HJ3 Compsoite Technoloies, LLC. The TMI Logo is a trademark of Tankhouse Maintenance, Inc.

4 TM TM Composite Technologies The Strongest Name in Carbon Fiber PIPE REPAIR KIT Step 1: Apply QuikFix Step 2: Wrap 1 st Layer of QuikFix Carbon Step 3: Saturate 1 st Layer of Carbon Fiber Step 4: Wrap a 2 nd or 3 rd Layer if necessary

5 HJ3 Uni-Directional Carbon Properties Corrosion Resistance Yes Chemical Resistance ph2-ph12.5 Tensile Strength (PSI) design 108,000 Modulus of Elasticity (ksi) 9,500 Effictive Ply Thickness (in).047 Installation Time per roll 20 Minutes Cure Time 6 to 8 hours Temperature 280 F HJ3 Bi-Directional Carbon Properties Corrosion Resistance Yes Chemical Resistance ph2-ph12.5 Tensile Strength (PSI) design 41,400 Modulus of Elasticity (ksi) 2,800 Effictive Ply Thickness (in).051 Installation Time per roll 20 Minutes Cure Time 6 to 8 hours Temperature 280 F HJ3 Pipe Repair Kits Contain: Uni-Directional or Bi-Directional Carbon Kits for Repairing Welds, Joints and Elbows Custom Designed Resin Systems for Chemical and High Temperature Applications Thixotropic Base Coats to fill pits and dimples Gloves Measuring Bucket Mixing Stick 5 Gallon Bucket for mixing resins and clean up Copyright 2008 HJ3 Composite Technologies, LLC. All Rights Reserved. All trademarks are the property of HJ3 Compsoite Technoloies, LLC. The TMI Logo is a trademark of Tankhouse Maintenance, Inc.

6 Internal Lining of Pre-Stressed Concrete Cylinder Pipe (PCCP) Case Study HJ3 CS Introduction Coal Fire Power Plants rely on large diameter Pre-Stressed Concrete Cylinder Pipe (PCCP) to transmit water to the plant cooling towers. Over time, the pre-stressing wires wrapped around the external circumference of the Pipe corrode causing pipe failures as the pipe cannot resist high internal pressures. The particular plant facility in this case required over 1000 linear feet of 12- Foot Diameter PCCP to be lined with carbon fiber to resist over 150-psi internal pressures. Problem Active Corrosion of the existing pre-stressing wires reinforcement was detected throughout the 300 linear feet of PCCP. Analysis of corroded areas showed that significant degradation had occurred and continued corrosion could result in loss of capacity and failure. Both carbon fiber and steel were initially considered to repair the PCCP. The repair had to be completed in 3 weeks during a plant shut-down. The repair also had to incorporate epoxy injection systems to eliminate leaking caused by hydrostatic pressure during the installation. Solution HJ3 engineers designed a repair that included two layers of HJ3 CF-516 to strengthen the pipe against internal hoop stress and 15-Foot of soil. Access to the pipe was granted in 3 separate locations through 36-inch manholes. The installation was staged in three steps: (1) abrasive blast, (2) Patch and Prime surface with HJ3 PM-100 and PC-200 Series resins, and (3) Installation of HJ3 CF-516 Carbon Fiber. Quality Control checks were instituted each day by HJ3 representatives to assure good adhesion (minimum of 250-psi) and eliminate all voids and air bubbles. The total installation was completed in 20 days. Conclusion The carbon fiber repair offered by HJ3 and its certified contractor created over 50% cost savings over the steel alternative repairs. The carbon system also minimized the flow restrictions created by steel slip-lined systems. The carbon installation also eliminated any need for welding or excavation. The repair was completed within the planned shut down window provided by the client. Copyright, All Rights Reserved. HJ3 Composite Technologies, LLC Jan. 1, 2003

7 Introduction Coal Fire Power Plants rely on large diameter Pre-Stressed Concrete Cylinder Pipe (PCCP) to transmit water to the plant cooling towers. Over time, the pre-stressing wires wrapped around the external circumference of the Pipe corrode causing pipe failures from failure to resist high internal pressures. The particular plant facility in this case required over 1000 linear feet of 12-Foot Diameter PCCP to be lined with carbon fiber to resist over 150-psi internal pressures. Problem Active Corrosion of the existing steel reinforcement was detected throughout the 1000 feet of PCCP. Analysis of corroded areas showed that significant degradation had occurred and continued corrosion could result in loss of capacity and failure. Both carbon fiber and steel were initially considered to repair the PCCP. One of the main difficulties on this project was the requirement that any repair be fully completed in the 14-day plant shut-down. When time of repair was considered carbon fiber became significantly cheaper than the steel alternatives. Solution HJ3 engineers designed a repair that included two layers of HJ3 CF-516 to strengthen the pipe against internal hoop stress. Access to the pipe was granted in 3 separate locations through 30-inch manholes. The installation was staged in three steps: (1) abrasive blast, (2) Patch and Prime surface with HJ3 PM-100 and PC-200 Series resins, and (3) Installation of HJ3 CF-516 Carbon Fiber. Quality Control checks were instituted each day by HJ3 representatives to assure good adhesion (minimum of 250-psi) and eliminate all voids and air bubbles. The total installation was completed in 11 days. Conclusion Over 100,000 square feet of carbon fiber was installed in less than 11 days to repair over 1000 linear feet of 12 foot diameter pipe. The project proves that carbon fiber is an efficient repair system for long runs of large diameter pipe that need to be repaired in a short period of time. The carbon fiber repair created over $2,000,000 in cost savings when compared to other steel alternatives each of which could not be installed in the time permitted. Internal Lining of Pre-Stressed Concrete Cylinder Pipe (PCCP) Case Study HJ3 CS Copyright, All Rights Reserved. HJ3 Composite Technologies, LLC Jan. 1, 2003