API RP 652-2014 pdf free download

API RP 652-2014 pdf free download.Linings of Aboveground Petroleum Storage Tank Bottoms .
3 Terms and Definitions For the purposes of this document, the following definitions apply. 3.1 aboveground storage tank A stationary container, usually cylindrical in shape, consisting of a metallic roof, shell, bottom, and support structure where more than 90 % of the tank volume is above surface grade. 3.2 anchor pattern Surface contour or roughness of a blast cleaned or substrate surface, when viewed from the edge. Also called profile. 3.3 anode The electrode of an electrolytic cell in which oxidation is the principal reaction. NOTE Electrons flow away from the anode in the external circuit. It is usually the electrode where corrosion occurs and metal ions enter solution. 3.4 caulk Products used to fair or smooth surfaces, as well as seal seams and rivets in lining applications. 3.5 cathode The electrode of an electrolytic cell at which reduction is the principal reaction. Electrons flow toward the cathode in the external circuit. 3.6 cathodic protection A corrosion control system in which the metal to be protected is made to serve as a cathode, either by the deliberate establishment of a galvanic cell or by impressed current. (See anode and cathode.)
3.7 coal tar epoxy A combination of epoxy, curing agent, and tar products which give a very water resistant film. 3.8 coating A paint or other finish used to create a protective or decorative layer. 3.9 concentration cell An electrolytic cell where the electromagnetic force (EMF) is caused by a difference in concentration of some component in the electrolyte. NOTE This difference leads to the formation of discrete cathode and anode regions. 3.10 corrosion The chemical or electrochemical reaction between a material, usually a metal, and its environment that produces a deterioration of the material and its properties. 3.11 cure, curing The process whereby a liquid coating becomes a hard film. Curing is complete when the lining is ready to accept immersion in the designated service. NOTE Methods of testing cure include solvent rub and hardness testing. 3.12 dew point Temperature at which moisture will condense from vapors into a liquid state. 3.13 differential aeration cell oxygen concentration cell A concentration cell caused by differences in oxygen concentration along the surface of a metal in an electrolyte. (See concentration cell.) 3.14 electrochemical cell An electrochemical system consisting of an anode and a cathode in metallic contact and immersed in an electrolyte. NOTE The anode and cathode may be different metals or dissimilar areas on the same metal surface. 3.15 electrolyte A nonmetallic substance that carries an electric current, or a substance which, when dissolved in water, separates into ions which can carry an electric current. 3.16 epoxy Extremely tough and durable synthetic coating resins that are highly resistant to chemicals, abrasion, moisture, and in some cases, alcohols.
3.17 forced-curing Acceleration of curing by increasing the temperature above ambient, accompanied by forced air circulation. 3.18 holiday A discontinuity in a protective coating that exposes unprotected surface to the environment. Application defects whereby small areas are left uncoated. 3.19 lining A liquid paint applied to the interior surfaces of a vessel that develops strong adhesion to the substrate and is designed for immersion service or vapor-space service for a specified stored product. NOTE A lining can be reinforced or unreinforced. 3.20 mil One one-thousandth of an inch (0.001 in.). NOTE One mil = 25.4 µm; it is common practice to use 1 mil = 25 µm. 3.21 mill scale The heavy oxide layer formed during hot fabrication or heat treatment of metals, typically a black-blue colored smooth layer found on the surface. 3.22 phenolic A resin of the phenol formaldehyde type. NOTE Phenolic and novolac epoxies tend to be more chemically resistant. 3.23 primer First complete coat applied to the prepared surface. NOTE Holding primers are often used in tank linings when operational issues require daily coating of the blasted surface. 3.24 profile See anchor pattern. 3.25 thick-film lining A lining with a dry film thickness of 20 mils (500 µm) or more. 3.26 thin-film lining A lining with a dry film thickness less than 20 mils (500 µm).