1、Interior Lining and Periodic Inspection of Underground Storage TanksAPI STANDARD 1631FIFTH EDITION, JUNE 2001REAFFIRMED, DECEMBER 2010Interior Lining and Periodic Inspection of Underground Storage TanksDownstream SegmentAPI STANDARD 1631FIFTH EDITION, JUNE 2001REAFFIRMED, DECEMBER 2010SPECIAL NOTESA
2、PI publications necessarily address problems of a general nature. With respect to partic-ular circumstances, local, state, and federal laws and regulations should be reviewed.API is not undertaking to meet the duties of employers, manufacturers, or suppliers towarn and properly train and equip their
3、 employees, and others exposed, concerning healthand safety risks and precautions, nor undertaking their obligations under local, state, or fed-eral laws.Information concerning safety and health risks and proper precautions with respect to par-ticular materials and conditions should be obtained from
4、 the employer, the manufacturer orsupplier of that material, or the material safety data sheet.Nothing contained in any API publication is to be construed as granting any right, byimplication or otherwise, for the manufacture, sale, or use of any method, apparatus, or prod-uct covered by letters pat
5、ent. Neither should anything contained in the publication be con-strued as insuring anyone against liability for infringement of letters patent.Generally, API standards are reviewed and revised, reafrmed, or withdrawn at least everyve years. Sometimes a one-time extension of up to two years will be
6、added to this reviewcycle. This publication will no longer be in effect ve years after its publication date as anoperative API standard or, where an extension has been granted, upon republication. Statusof the publication can be ascertained from the API Downstream Segment telephone (202)682-8000. A
7、catalog of API publications and materials is published annually and updatedquarterly by API, 1220 L Street, N.W., Washington, D.C. 20005.This document was produced under API standardization procedures that ensure appropri-ate notication and participation in the developmental process and is designate
8、d as an APIstandard. Questions concerning the interpretation of the content of this standard or com-ments and questions concerning the procedures under which this standard was developedshould be directed in writing to the standardization manager, American Petroleum Institute,1220 L Street, N.W., Was
9、hington, D.C. 20005. Requests for permission to reproduce ortranslate all or any part of the material published herein should also be addressed to the gen-eral manager.API standards are published to facilitate the broad availability of proven, sound engineer-ing and operating practices. These standa
10、rds are not intended to obviate the need for apply-ing sound engineering judgment regarding when and where these standards should beutilized. The formulation and publication of API standards is not intended in any way toinhibit anyone from using any other practices.Any manufacturer marking equipment
11、 or materials in conformance with the markingrequirements of an API standard is solely responsible for complying with all the applicablerequirements of that standard. API does not represent, warrant, or guarantee that such prod-ucts do in fact conform to the applicable API standard.All rights reserv
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13、D.C. 20005.Copyright 2001 American Petroleum InstituteFOREWORDAPI Standard 1631 provides recommendations for lining the interior of existing steel andberglass reinforced plastic underground petroleum storage tanks and periodic inspectionsof lined steel tanks. This standard was prepared under the aus
14、pices of the API Manufactur-ing, Distribution and Marketing Department and is based upon the experience of knowledge-able members of the petroleum industry and lining manufacturers. This standard is intendedfor use by API member companies and others to develop safe practices and procedures forlining
15、 and inspecting underground tanks storing petroleum products. A number of additionalAPI standards and recommended practices as well as government and industry regulationsand publications, noted in the reference section, provide supplemental information applica-ble to the requirements and components
16、of this standard. API publications may be used by anyone desiring to do so. Every effort has been made bythe Institute to assure the accuracy and reliability of the data contained in them; however, theInstitute makes no representation, warranty, or guarantee in connection with this publicationand he
17、reby expressly disclaims any liability or responsibility for loss or damage resultingfrom its use or for the violation of any federal, state, or municipal regulation with which thispublication may conict.Suggested revisions are invited and should be submitted to the standardization manager,American
18、Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005.iiiCONTENTSPage1 GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19、. . . . . . . . . . . . . . . . . . . 11.2 Applicability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.3 EPA Technical Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 REFERENCES . . .
20、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.2 Industry and Consensus Codes, Standards and Publications . .
21、 . . . . . . . . . . . . . . 12.3 United States Government Regulations and Standards. . . . . . . . . . . . . . . . . . . . . 23 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.1 General . . . . . . . . . . . . . . . . .
22、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.2 Denitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.3 Use of Other Units (Conversion). . . . . . . . . . . . . . . . . . . . . . . . . . . .
23、. . . . . . . . . . 74 OBJECTIVES, REQUIREMENTS AND SPECIFICATIONS. . . . . . . . . . . . . . . . . . . 74.1 Objectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74.2 Permit and Training Requirements . . . . . . . . . . . . . . . .
24、 . . . . . . . . . . . . . . . . . . . . 74.3 Tank Lining Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 PREPARATION FOR OPENING THE TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.1 Safety Precautions . . . . . . . . . . . . .
25、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.2 Sources of Ignition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.3 Tank Isolation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26、. . . . . . . . . . 85.4 Removal of Liquid Product . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95.5 Removal of Flammable Vapors (Vapor-Freeing) and Ventilation. . . . . . . . . . . . . 95.6 Testing Flammable Vapor Concentrations. . . . . . . . . . . . . . . .
27、. . . . . . . . . . . . . . 106 TANK ENTRY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106.1 Providing a Tank Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106.2 Tank Entry Precautions . .
28、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116.3 Potential Toxicity and Health Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 PREPARATION OF THE TANK INTERIOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147.1 Slud
29、ge Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147.2 Potential Toxic Exposures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147.3 Tank Inspection . . . . . . . . . . . . . . . . . . . . . . . . . .
30、 . . . . . . . . . . . . . . . . . . . . . . . . 147.4 Surface Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 APPLICATION OF LINING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168.1 Entry and S
31、afe Work Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168.2 Lining Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168.3 Steel Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32、. . . . . . . . . . . . . . . . . 168.4 Fiberglass Tanks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178.5 Lining Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17vPage9 RETURNING TA
33、NKS TO SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179.1 Steel Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179.2 Fiberglass Tanks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
34、 . . . . . . . . . . . . . . . . . . 199.3 Tank Tightness Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1910 PERIODIC INSPECTIONS OF PREVIOUSLY LINED STEEL TANKS . . . . . . . . 1910.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
35、 . . . . . . . . . . . . . . . . . . . . . . . . . . . 1910.2 Tank Preparation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1910.3 Video Inspections of Tank Linings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2010.4 Physica
36、l InspectionsTank Lining Requirements . . . . . . . . . . . . . . . . . . . . . . 2010.5 Physical InspectionTank Metal Thickness Requirements . . . . . . . . . . . . . . . 2010.6 Tank Closure or Upgrading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Figures1 Educ
37、tor-Type Air Mover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 Diffused Air Blower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Method for Installation of Tank Cover Plate . . . . . . . . . . . .
38、 . . . . . . . . . . . . . . . . . 184 Alternate Cover Plate Installation Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18FormsFORM ACONTRACTORS EMPLOYEE CONFINED SPACE ENTRY generally con-sidered to be too lean to burn.INTERIOR LINING OF UNDERGROUND STORAGE TANKS 53.2.18.2
39、Upper Explosive (flammable) Limit (UEL):The maximum concentration expressed as a volume (percent-age) of a vapor-in-air above which propagation of ame doesnot occur upon contact with an ignition source; generallyconsidered too rich to burn.3.2.19 flammable liquid: A liquid having a closed cupash poi
40、nt below 100F (37.8C).3.2.20 flammable vapor: The gaseous phase of a sub-stance that is a liquid at normal temperature and pressure andis capable of igniting and burning when mixed with air (oxy-gen) in the proper proportion and subjected to a source ofignition. Under normal ambient temperatures, Cl
41、ass IA andClass IB liquids generate sufcient vapors to create amma-ble vapor concentrations at all times. Vapors from ammableand combustible liquids are heavier than air.3.2.21 flammable vapor Indicator: (see combustiblegas indicator). 3.2.22 hazardous atmosphere: An atmosphere thathas the potential
42、 to expose entrants to the risk of death, inca-pacitation, impairment of ability to self-rescue (escapeunaided from a permit required conned space), injury oracute illness from one or more of the following causes: Flammable gas, vapor or mist in excess of 10% LEL. Airborne combustible dust at a conc
43、entration that meetsor exceed 80% of its LEL. Atmospheric oxygen concentration different fromambient. An oxygen level below 19.5% signies anoxygen deciency and a level above 23.5% signies anexcess of oxygen. Atmospheric concentration of any substance for whicha dose or permissible exposure limit is
44、published inapplicable government regulations, Material SafetyData Sheets, standards or other publications or internaldocuments, and could result in employee exposure inexcess of the substances dose or permissible exposurelimit (PEL). Any other atmospheric condition immediately danger-ous to life or
45、 health (IDLH). 3.2.23 hazardous (substance) material: A substanceor material that is capable of harming people, other materials,property or the environment. These substances may be liquid,solid or gaseous and toxic, corrosive, ammable, reactive orotherwise hazardous.3.2.24 hot work: Any work that h
46、as the potential to pro-duce enough thermal energy to provide an ignition source inan area where a potential exists for a ammable gas or vapor-in-air atmosphere in the explosive (ammable) range tooccur, such as abrasive blast cleaning the inside of a tank.3.2.25 instruments: The oxygen monitors, com
47、bustiblegas indicators and toxic substance analyzers (measuringequipment) used to test (or sample) atmospheric conditionsand determine, indicate, measure and monitor the amount ofoxygen in the atmosphere and presence of hazardous sub-stances, including percentage of ammable gas or vapor-in-air and c
48、oncentrations of toxic substances. 3.2.26 isolation: The process by which a permit requiredconned space or non-permit conned space is removed fromservice (decommissioned) and completely protected againstthe release of energy or material into the space. Isolationincludes, but is not limited to, blank
49、ing or blinding; breaking,misalignment of, opening or removing sections of lines orpipes; using a double block and bleed system; lockout or tag-out of all sources of energy; locking, sealing and tagging allvalves; and blocking and disconnecting all mechanical link-ages (see lockout/tagout).3.2.27 lead free tank: A tank that has been certied bythe owner/operator as never having been used to store leadedgasoline, lead additives or products that have contained lead.Alternately, a tank that has been cleaned according to API Std2015, tested for lead-in
