1 Cathodic Protection Equipment &. Pipeline Supplies GENERAL. Cathodic Protection (CP) is a proven method of Sacrificial Anode controlling and reducing corrosion of pipelines, vessels, tanks and other structures, located both above and below ground. The added expense of installing CP systems is usually justified based on Impressed Current Anodes pipe or vessel repair/replacement costs. This type of anode can be classified as either Corroding structures have both anodic and decaying or non-decaying (stable). Impressed current Cathodic areas. Electrons naturally flow from the systems require the anode to be energized in order to anodic areas through an electrolyte (for example soil) function. Current requirements increase with to the Cathodic areas and back to the pipe, thereby temperature, H2S and SRB's. completing a circuit. Corrosion occurs where the current discharges from the metal into the electrolyte TYPE OF.
2 ADVANTAGES DISADVANTAGES. SYSTEM. at anodic areas. By applying Cathodic Protection to a structure, the entire exposed surface can become simple & reliable less flexibility to Cathodic to the environment, thereby mitigating the low maintenance change once in unaffected by service corrosion. Sacrificial lightening strikes or additional anodes power failures must be installed to Cathodic Protection has also been shown to be typically less increase current effective in reducing corrosion underneath biomass expensive output (SRB) colonies, by impeding their attachment to the flexible to operate require a power steel surface. voltage & current source adjust manually or need closer ANODES automatically monitoring &. Impressed Current anodes typically maintenance Anodes are a metal that have a different supply higher significantly higher EMF/potential compared to a corroding structure.
3 Ampere-hours of cost When attached to the structure, they provide current Protection by corroding preferentially. Two types of Sacrificial anodes can be insulated from the anodes are available: sacrificial and impressed vessel for measuring current output through a short current type. length of exposed wire and a shunt. Anodes can be Sacrificial Anodes suspended from tank decks, allowing easy replacement without taking the vessel out of service. The three most common types of sacrificial anodes are: activated aluminum, zinc and Flange mounting provides the most secure magnesium. Aluminum is the most widely-used method of placing an anode through a pressure material for anodes, as it has a higher current vessel wall. The use of an anode adaptor allows capacity in comparison to the other metals. trouble-free installation of sacrificial vessel anodes Magnesium should be considered when the chloride (see diagram on following page).
4 Content is less than 10,000 ppm. Sacrificial anodes Caproco Supplies an array of anode adaptors. The do not require any external power source in order to standard adaptor is suitable for aluminum or zinc operate. anodes 22" (560mm) long x 3" (76mm) diameter. SACRIFICIAL ANODES (P/N). FLANGED ANODE ADAPTOR (A105). Aluminum Treater 84023 (other types 4" 150# 84052. (3" x 22" / 76 x 560 mm). available upon 17 lb Packaged request) 4" 300# 84057. 84057. Magnesium 4" 600# 84059. REFERENCE CELLS Insulating sleeves and washers are available in high density polyethylene, NEMA grade LE phenolic Reference cells are a dependable method of and mylar, and also come as integrated one-piece taking a potential measurement in order to verify units. the correct functioning of a Cathodic Protection system. The three most common types of cells Flange protectors and corrosion inhibitor grease used are: copper/copper sulphate, silver/silver- help to eliminate the possibility of any matter chloride and zinc.
5 Portable reference cells can be penetrating between the flange faces, preventing used to measure potentials on above and below- corrosion bridging which could lead to a short. ground structures, and are refillable. All insulating parts are available in higher Kirk electrolytic grounding cells act as an pressure & temperature ratings and material electrochemical switch, redirecting any hazardous options upon request. voltage surge to ground. Grounding cells are THERMOWELD Equipment . designed to not interfere with the lower current flow of the Cathodic Protection system. Thermoweld Equipment is especially designed to bond cables onto piping, and is a common INSULATION KITS. method for attaching CP cables to pipes or other Caproco offers an array of insulation kits for structures. Pipeline connections, including flange gaskets, Handy caps are designed to fit over the welded protectors, sleeves and washers.
6 Cable connection and are installed simply by Flanged connections must be properly sealed to pressing firmly into place. Typically, new cadweld prevent leakage, and should be cathodically installations are given a coating of mastic and then insulated to prevent any stray currents from causing taped to prevent accelerated corrosion at the corrosion. Insulating gaskets are available in three connection point. basic designs, depending on the fitting option MISCELLANEOUS Supplies . desired: Caproco can provide various Pipeline Supplies Type D - fits the ring groove of ring-type-joint upon request, such as: hand roll tape, colored dye flanges (for leak detection) and wire/cable. Talk to your Type E - full-faced with precision cut bolt holes nearest Caproco representative for all your Cathodic Protection needs. Type F - fits the raised face portion of the flange All gaskets are available in phenolic, and are sized to ANSI specifications.