1、Designation: F 1754 97 (Reapproved 2004)An American National StandardStandard Guide forMarine Vessel Structural Inspection Considerations1This standard is issued under the fixed designation F 1754; the number immediately following the designation indicates the year oforiginal adoption or, in the cas
2、e of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers information to develop and imple-ment a marine vessel inspection process
3、. It is intended toprovide considerations for persons interested in planning,organizing, and implementing a structural survey plan for amarine vessel, especially during the design phase of the vessel.It is intended to be used in conjunction with any other requiredinspection or survey requirements bu
4、t can form the basis forsuch planning in the absence of other such applicable require-ments.1.2 This guide provides owners, operators, shipyards, anddesigners with a plan for developing a detailed inspectionprocess that covers all stages of the operating life of a marinevessel, including the design,
5、 construction, and in-service peri-ods. This plan may be developed and used in concert withclassification society and flag state surveys and inspections.1.3 This guide also provides the basis for development of arecommended corrective action plan for typical structuraldeficiencies or deviations, or
6、both.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.5 All po
7、rtions of this guide may not be applicable to allvessels or shipyards since many yard-specific standards toensure contracted level of quality are in existence.2. Referenced Documents2.1 ASTM Standards:2F 1053/F 1053M Guide for Steel Hull Construction Toler-ances Metric33. Terminology3.1 Definitions
8、of Terms Specific to This Standard:3.1.1 blind spots, nareas of a vessels structure thatcannot be visibly or electronically inspected for failure.3.1.2 large tanks, ntanks of such dimension as to haveuninspectable heights greater than 10 m.3.1.3 telltale areas, nareas of a ships structure identified
9、by analyses and investigations during design development asbeing subject to higher stresses or more susceptible to fatiguethan others, even though the higher stresses are still withinallowable limits. Also, areas identified after the vessel is placedin service that continue to experience active or r
10、ecurringcracking in the watertight envelope or that affect the structuralintegrity of the vessel.4. Introduction4.1 As stated earlier, the intent of this guide is to assist in thepreparation of an inspection plan for a marine vessel during itsdesign, construction, and in-service stages and to plan f
11、orinspection during the design. This guide should be used in thepreparation of a specific inspection program for the construc-tion of a specific marine vessel. It is not intended to set anystringent requirements for the structural inspections of anyparticular vessel. The suggestions for various insp
12、ection con-siderations in this guide are presented for the purpose ofmaking available for review and use a broad set of guidelines.4.2 This guide is applicable to all commercial and pleasuremarine vessels. Although the references generally apply tosteel and aluminum welded hulls, the overall aspects
13、 may beapplied to any material or type of construction.4.3 At any point of its construction or service life, the vesselmay require classification society or flag state regulatoryinspections, or both, as well as shipowners surveys. Thesurveys, depending on occasion, should consider the generalconditi
14、on of the vessel, provide a detailed condition assess-ment, obtain data to determine corrosion rate and damage, orobtain information for repair specification development, or acombination thereof. The inspection plan should take intoaccount all of these types of information in its development.On occa
15、sions, the surveys also should obtain data on rate ofcoating breakdown.4.4 Because of severe loadings, excessive wastage, poorstructural design, improper use of materials, excessive fatiguecycling, and so forth, failure may occur at any structurecomponent at some stress value that is much less than
16、thetheoretically allowable limit. Therefore, detection of such1This guide is under the jurisdiction of ASTM Committee F25 on Ships andMarine Technology and is the direct responsibility of Subcommittee F25.01 onStructures.Current edition approved May 1, 2004. Published May 2004. Originallyapproved in
17、 1996. Last previous edition approved in 1997 as F 1754 - 97.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.
18、3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.conditions by careful analysis and by sufficient inspectionthroughout the entire process is consequently crucial for theprevention of failure. This guide describes genericall
19、y theextent of and the procedures for inspections to be performed ateach stage of a marine vessels life. Minor and major imper-fections can be detected early in the construction process.Therefore, structural integrity can be maintained with periodicin-service inspections and appropriate and timely c
20、orrectivemeasures to prevent any accumulation of defects or costlyrework.4.5 From construction and early service life inspections, astructural history of the vessel can be prepared forming thebasis on which future in-service inspection results can beevaluated.5. Inspection Considerations During Desi
21、gn Stages5.1 To ensure the marine vessels structural integrity, thedesigners should consider the following inspection-relatedrequirements during the design stages:5.1.1 Inspectability of a Marine Vessels Structure DuringConstruction and In-Service:5.1.1.1 BackgroundDuring the life of any marine vess
22、el,several inspections are conducted on the structure. Theseconsist of two types that directly reflect their purpose, conve-nience and regulatory. In conducting either one, certain loca-tions require access that are not readily accessible withoutclimbing the structure or obtaining assistance from me
23、chanicaldevices. When an inspection requires the use of mechanicalmeans to access the structure, several options are available.They include anything from a simple platform elevated by ahoist connected at the overhead to a sophisticated ROV(Remote Operated Vehicle) that permits the inspector to remai
24、noutside the tank altogether. An issue that must be recognized isthe degree of inspection. In other words, how close does onewant to be to the structure, how accurate does the inspectionneed to be, and how long does one have to conduct theinspection. The definition of the “degree of inspection” has
25、adirect bearing on the conclusions drawn from informationpresented herein.5.1.1.2 For the purposes of this guide, the following as-sumptions are made relative to the degree of inspection:5.1.1.3 The inspected structure must be in direct line ofsight.5.1.1.4 The inspected structure must be in clear a
26、nd distinctview, taken as a distance of not more than 1.5 m (5 ft) fromones eyes.5.1.1.5 The structure is to be inspected to a degree thatwould reveal almost all fractures that have a length of 50 mm(2 in.) or more. This depends significantly on the cleanliness,lighting level, stress, and so forth,
27、of the structure.5.1.1.6 The inspection shall be conducted in a continuousmanner such that the shortest amount of time is taken for it.5.1.1.7 For the purposes of inspection, the structure shouldbe broken down into discrete zones, such as those depicted inFig. 1. Where the structure differs from tha
28、t depicted in Fig. 1,an appropriate scheme of identifying zones for inspectionshould be adopted.(1) Zone 1The bottom and inner bottom shell structureincluding the turn of bilge and any structure attached to them.(2) Zone 2The deckhead structure, from ships side toships side, including the stiffening
29、 attached to it.(3) Zone 3The side shell structure, including the sidebulkhead structure for double hull vessels, including thestiffening attached to it.(4) Zone 4The longitudinal bulkhead structures thatinclude the centerline and side longitudinal bulkheads, excepta side bulkhead of a double hull s
30、tructure.(5) Zone 5The transverse bulkhead structure, fore and aftsides, extending from the bottom shell to the deckhead.5.1.2 Access Methods:5.1.2.1 Fixed StagingThis method consists of poles, fit-tings, planks, and ladders that create a tower or walkway. Thisis the only method that permits access
31、to all structural areas ofa vessel. To achieve this coverage, however, it is very expen-sive and time consuming. A simple description of the methodcould be compared to an erector set. It is a straightforwardmethod to which most people can relate. It may be a methodthat more people feel comfortable u
32、sing than some. Accessinga deckhead structure that is 20 m (66 ft) or so above thebottom, however, is not a place for anybody with a fear ofheights. This method has been a standard access method forconducting inspections and repairs to vessels for many years.The components are better designed and li
33、ghter in weight thanten or more years ago. Therefore, it is more easily constructedtoday.5.1.2.2 Portable StagingThis method consists of a plat-form of sufficient size to carry at least one person. It alsoincludes a winch that is attached to the platform. The wire onthe winch is connected to the und
34、erdeck structure so that theplatform raises towards the wires connection point at theunderdeck. The size of the platform varies. Some are sized tolift only one person while others are sized to lift up to four orfive persons. In fact, some platforms are similar to those usedby window washerslightweig
35、ht and breakdown for portabil-ity. For industrial applications, the staging is built more ruggedFIG. 1 Hull Girder Structure Areas Designated by ZonesF 1754 97 (2004)2than typically used for window washers, such that the designload is higher. Persons on the staging should have individualsafety harne
36、sses attached to them. The Occupational Safetyand Health Administration (OSHA) has become more active inverifying contractors perform their work in a safe manner. Onehigh-risk aspect of using this staging is attaching the liftingwires to the overhead. This normally is accomplished by aperson walking
37、 the deckhead. This person uses a set of stirrupseach attached to one end of a short length of wire with sometype of hook at the opposite end. The hooks fasten into thedeckhead structure, then a person proceeds to walk across thedeckhead while moving the stirrups and connecting the plat-forms liftin
38、g wires to the deckhead. OSHA has become moreaware of this activity due to fatalities. They now require thesepersons to wear safety harnesses connected to lifelines. Analternate method of attaching the lifting wires to the overhead,but not normally used, is by drilling holes into the deck andpassing
39、 wires through them. The wire end is then secured toprovide a holding point. The problem is that drilling holes intoa deck is not a desired situation. It can become a source offuture fracture problems if not properly done and might belocated in an area of high stress.5.1.2.3 RaftingThis is a straigh
40、tforward system and maybe the easiest to understand. It consists simply of rowingaround in a rubber raft while the water level in the tank ischanged in height. This method has been used for many years,not only for inspection reasons, but also for access to upperregions of a tank by the vessels crew
41、for conducting repairs. Infact, there are various objects that can be used to providebuoyancy when access to high areas in a tank is needed and arubber raft is not available. For structural inspections, normallytwo persons occupy a raft; this enhances the rafts maneuver-ability and the inspection. A
42、ll areas of the structure can beaccessed easily from the level of the liquid. Vessels with deeptransverse structures, however, prohibit safely accessing thedeckhead structure. If the water rises, it traps the raftsoccupants between the structure and water level without a safeexit from the tank. This
43、 applies to any tank with a deckheadstructure to some degree. An important aspect of this methodrelating to the thoroughness of an inspection is the rate of waterlevel change. If the intervals are too great, such as 5 m (16.5 ft)or more, only those areas immediately above the water levelare really s
44、urveyed close-up. This method can be implementedto inspect the structure continuously while changing the waterlevel. The rate of level change can be controlled to permitsighting nearly 100 % of the accessible structure.5.1.2.4 ClimbingThis method often complements one ofthe other methods mentioned i
45、n the preceding sections. Itvaries from climbing the structure a short distance to see aparticular location better, to climbing the height of the tankwith the aid of a safety harness. The latter, although demon-strated, is not typically used. There are hazards when climbingany height; the higher one
46、 goes, the greater the risk of severeinjury if one falls. Prudent judgment, therefore, is necessary toprevent accidents. This includes a decision to not climb to anyheight if the circumstances so indicate, for example, slipperyconditions, physical problems, and so forth.5.1.2.5 OtherThe inspection m
47、ethods here are not consid-ered to be primary methods but rather ones that can support andenhance one or more of the methods previously described.They serve a specific purpose.5.1.2.6 ZiggyThis mechanical device consists of a mecha-nism positioned above the deck that raises and lowers, androtates fr
48、om side to side, with a steel column constructed ofshort, rectangular tubes. The tubes are lowered through abutterworth hole to the bottom. A horizontal beam is attachedto the bottom end of the column, and a single-person basket isattached to the other end of the beam. As the column is raisedor lowe
49、red, the person in the basket can extend oneself to adistance between 3 and 9 m (10 and 30 ft) from the verticalcolumn. This device permits one to inspect the side andunderdeck structure without building a tower of staging,climbing the side shell, or filling the tank with water to theunderdeck. It can be operated from the basket or from the deckpositions.5.1.2.7 Remote Operating Vehicle (ROV)An ROV is simi-lar to a miniature undersea, unmanned vehicle. This methodalso requires filling the tank with water. Unlike the raftingmethod, however, it is importa
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