Chapter 2 Certification
2.2 Works Approval and Quality Assurance
2.2.1 The container manufacturer who intends to produce containers to be certified by the Society is to be subjected to works approval. The Society is to be satisfied that the manufacturer is to have the adequate technica l ability, production facilities, workmanship, quality control, test and inspection system, etc. for the series production of containers in satisfactory and consistent quality.
2.2.2 For works approval, the manufacturer is to submit the following documents concerning the production of containers for approval by the Society in satisfactory manner:
(a) Outline of works.
(b) Container manufacturing procedure.
(c) Main facilities for the production.
(d) Facilities for tests and inspections.
(e) Manufacturer’s standards for inspection and process of quality control.
(f) Other documents as required by the Society.
is to submit the following design plans and documents to the Society for approval before the construction of the prototype unit is commenced:
(a) General arrangement and specification.
(b) Structural drawing showing materials, scantlings and structural details.
(c) Test and inspection procedures.
(d) Other documents as required by the Society.
2.3.2 A prototype unit of the container intended for type approval is to be prepared and subjected to a satisfactory test and inspection in compliance with the relevant requirements given in the Rules witnessed by the Surveyor.
2.3.3 A type approval certificate for the approved design type container is to be issued subject to the satisfaction of the requirements given in 2.3.1 and 2.3.2 above.
2.3.4 A type of container is assumed to include those built in accordance with the same basic design and specifications. However, the Society may consider it the same type as the original one even if minor alterations to structural arrangements or variations in fittings are made in containers of the type approved.
2.3.5 For a type of container designed and constructed to other standards than the Rules or a type of container has been approved by other recognized organizations, type approval for such types of container may be accepted subject to the special consideration and approval by the Society in each case.
2.4 Certification for Production Units
2.4.1 Production units of approved type series container intended for certification by the Society are to be subjected to a satisfactory test and inspection witnessed by the Surveyor at proper stages during construction in compliance with the relevant requirements given in the Rules.
2.4.2 The manufacturer is to prove to the Surveyor’s satisfaction that the manufacturing construction, material, quality, etc. of production units are at least equal to those of the prototype container. When in the judgment of the Society, unacceptable workmanship, material or quality control procedures are evident, certification of production units may be withheld pending correction of the defect to the Surveyor’s satisfaction.
2.4.3 Where production units are produced under satisfactory quality assurance system approved by the Society, tests and inspections for such production units carried out by the manufacturer may be accepted provided they have been executed to the Surveyor’s satisfaction.
2.4.4 Test items and the number of containers selected for tests may be modified depending upon test results previously obtained and subject to the approval of the Society.
Chapter 3 Design
3.1 Dimensions and Rating
3.1.1 Overall external dimensions, permissible tolerances and the maximum gross weight of ISO series 1 freight containers are shown in Table 3-1. The dimensions and tolerances apply when measured at the temperature of 20C, and the measurements taken at temperature other than 20C are to be adjusted accordingly.
3.1.2 All containers have a unifying nominal width of 8 ft (2,438 mm). Those designated by a single letter have a nominal height of 8 ft (2,438 mm); those which have a double letter have a height of 8.5 ft (2,591 mm); and those designated by X indicates that the height of the container is between 0 and 8 ft (2,438 mm). Containers designated by A have a nominal length of 40 ft (12 m), B 30 ft (9 m), C 20 ft (6 m), D 10 ft (3 m). Reduced heights are per missible within the X designation for tank, open top, platform and platform based-type containers.
3.1.3 The construction is to be structurally sound and weathertight, and all fixtures and fittings are to be within the overall external dimensions.
3.1.4 The difference between dimensions D1 and D2, D3 and D4, D5 and D6 measured diagonally across the container from centers of top and bottom apertures on the roof and base, on side walls, on front and rear walls respectively, shown in Fig. 3-1, are not to exceed the permissible variation given in Table 3-2.
Table 3-1
Overall External Dimensions, Permissible Tolerances and Maximum Operating Gross Mass of ISO Series 1 Freight Containers
Container Designation
Length, L, (mm) Width, W, (mm) Height, H, (mm) Max. Operating
Gross Mass, Dimension Tolerances Dimension Tolerances Dimension Tolerances R, (kg)
1A 12,192 0 10 2,438 0 5 2,438 0 5 30,480
Fig. 3-1 Diagonal Tolerances
Table 3-2 Diagonal Tolerances
ContainerDesignation Maximum Permissible Varations (mm) on Roof and Base D1D2
on Side Walls D3D4
on Front and Rear Walls
D5D6
1A 1AA 19 10
1B 1BB 16 10
1C 1CC 13 10
1D 10 10
3.2 Fittings
3.2.1 Each container is to be equipped with corner fittings at top and bottom corners. The dimensions and tolerances of corner fittings are to conform to Figs. 3-2 and 3-3. Each container is to have 2 right-hand top corner fittings (on the right as the observer faces the container) and 2 left-hand top corner fittings which are the mirror opposite of the right-hand fittings. For bottom corner fittings, a similar configuration is to exist. Corner fitting drawings illustrate right-hand (RH) top and bottom corner fittings only; for left-hand (LH) corner fittings the dimensions are simply transposed.
3.2.2 Hinges, closing devices and their fittings to the container are to be of suitable material not subject to easy deformation or wear that may impair the safety and tightness of the closure.
3.3 Materials and Workmanship
3.3.1 General(a) Materials used for strength structures of containers are to be in compliance with the appropriate recognized material standard or, if applicable, the requirements given in Part XI of the “Rules for the Construction and Classification of Steel Ships” (hereinafter referred to as “Rules for Steel Ships”). Sufficient information of materials containing manufacturing procedures, grades, mechanical properties, the chemical composition, heat treatments, etc. are to be submitted to the Society for approval.
(b) Structural members of containers are to be of incorrodible materials or subjected to a suitable anticorrosive treatment.
3.3.2 Steels
(a) The choice of the steel type is to be adequate to uses, kinds of structure, thicknesses, bending and to the working and welding requirements. Particular attention is to be paid to working conditions at low temperatures and tanks subject to pressure.
(b) Corner fittings are to be of cast steel or materials with equivalent ductility. Where welding is intended, these are to be of weldable quality.
3.3.3 Aluminium alloys
(a) Alloys are to be incorrodible in marine environments. For this purpose, the copper content is not to exceed 0.05%.
(b) On aluminium alloy plates no altering working is allowed such as direct hammering, heating, surface grinding. Where welding is applied, welded joints are to be capable of maintaining satisfactory properties.
(c) Connections with steel parts are to be carefully worked out, making use of suitable insulation materials.
3.3.4 Timbers
(a) Timbers are to be of good quality, well seasoned, so far as possible free from sapwood, nots, cracks and pits, and in general free from defects that may compromise their soundness and durability.
(b) Plywoods are to be of marine resistant type made up of wood layers treated to protect them against ma rine conditions, and built according to the good practice. Plywood edges are to be protected by glues, varnish or other suitable compositions against moisture penetration and wear.
(c) Wooden surfaces that are not accessible after assembly in place are to be previously coated with linseed oil or other suitable compositions for protection against moisture. Surfaces exposed to contact with water are to be adequately treated, with linseed oil or other substances against rottenness.
3.3.5 Plastics
(a) Reinforced plastics are to be fabricated by competent manufacturer and production procedures are to be recognized by the Society.
(b) The Society has issued particular rules for construction of ships of reinforced plastics, which may constitute a useful guide for fabrication of such material even when intended for use in containers.
(c) The use of rigid expanded plastic materials of prefabricated panels and/or foamed into place for insulation of thermal containers is to be approved by the Society.
3.3.6 Others
(a) The welding for strength structures of containers, containing welding procedures, welder qualifications, operation controls, welding materials, etc., are to be in compliance with the requirements given in Part XII of the Rules for Steel Ships unless otherwise specially approved
Fig. 3-2 Top Corner Fitting (Dimensions in mm)
Fig. 3-3
Bottom Corner Fitting
(Dimensions in mm)
Notes to Fig. 3-2 and 3-3:
1. Solid and dotted lines ( and---) show surfaces and contours which must be physically duplicated in the fitting.
2. Phantom lines ( -- --) show optional walls, which may be used to develop a box-shaped fitting.
3. Outside and inside corner radii where sharp corners are shown must be 3 mm maximum except as noted.
4. Four fittings are required per container: two right-hand and two left-hand.
(b) Glues, caulking materials and gaskets are to be of good marine quality and resistant to maximum and minimum temperatures to be expected in service.
(c) All steel work is to be suitably coated with paint or equivalent coating. Protective coatings on wooden materials are to remain unaltered and such as not to cause damages to the cargo.
3.4 Design Load
3.4.1 The container is to be so designed as to be capable of sustaining the design load specified in Table 3-3.
Table 3-3
Design Load of Containers(1/2)
Items Type of Load Direction of Load Design Load Remarks
Stacking
Top lifting Concentrated at pick-up points on 4 top corner fittings
Vertically upward for container 1A, 1AA, 1B, 1BB, 1C and 1CC.
30 to the vertical for container 1D
2R (each corner to take1/4 of design load)
Bottom lifting Concentrated at pick-up points on 4 bottom
Table 3-3
Design Load of Containers (2/2)
Items Type of Load Direction of Load Design Load Remarks
Floor loads Concentrated at contact areas of two wheels
Chapter 4
Tests and Inspections
4.1 General
4.1.1 Tests and inspection requirements given hereunder are generally applied to general cargo containers, thermal containers and tank containers unless otherwise specified. Requirements for containers of special type, purpose or feature may be modified or specially considered at the prescription of the Society.
4.1.2 Special requirements of tests and inspections for thermal containers and tank containers are additionally specified in 6.5 and 7.5 of the Rules respectively.
4.1.3 Alternative tests and inspection procedures may be accepted if considered to be equivalent to the requirements given in the Rules. The Society may specially consider the requirements for tests and inspections according to other standards when deemed appropriate.
4.1.4 Measuring instruments to be used for tests and inspections are to be calibrated.
4.1.5 On completion of tests, the container is to remain serviceable and is not to show any significant permanent deformation or abnormality which may make it unsuitable for use.
4.2 Inspections of Materials
4.2.1 Materials used in the construction of containers are to comply with the approved design specification of containers.
4.2.2 For materials of strength structures and corner fittings, the manufacturer is to provide the Surveyor with mill sheets containing the information of dimensions, quantity, charge and piece numbers, grades, mechanical properties, chemical compositions, conditions of heat treatment, etc. Testings for such materials at mills may be required to carry out in the presence of the Surveyor as deemed necessary by the Society.
4.2.3 Visual inspections and dimensional checks for each piece of corner fittings are to be carried out in compliance with the requirements of the Rules. Nondestructive examinations and/or compression tests for corner fittings may be required additionally where deemed necessary by the Surveyor.
4.2.4 Strength characteristics of reinforced plastic structures are to be ascertained, where necessary, by means of tensile and impact tests which are to be recognized by the Society.
4.2.5 Insulating materials are to be ascertained subject to successful results of tests made recognized standards.
Tests such as density control, control of contents, self-extinguishing test and vibration test are to be carried out.
4.3 Tests and Inspections for Container Construction
4.3.1 Visual inspections(a) A visual inspection for each container is to be carried out at a proper stage and period during construction and/or after completion. For insulated containers, the visual inspection is to b e conducted prior to commencement of the insulating work.
(b) The construction, material and workmanship of the container are to be ascertained in compliance with the requirements of the Rules without any visual defects in each component of the container.
(c) For containers fitted with doors or other closing appliances, it is to be ascertained that they can be smoothly operated and secured.
4.3.2 Dimensional checks
Each container is to be dimensionally checked after the completion of all the work to ascertain that the container meets the dimensional requirements given in the Rules.
4.3.3 Mass measurement
Mass measurement is to be carried out after the completion of all the works to determine the tare of the container.
4.3.4 Weathertightness tests
(a) A stream of water is to be applied over all exterior surface from a nozzle of 12.5 mm inside diameter, at a pressure of about 0.1 MPa. The nozzle is to be held at a distance of 1.5 m from the part under test with a rate of movement over the exterior of approximately 0.1 m per second. On completion of the test, the container is to be free from penetration of water.
(b) The weathertightness test is to be conducted after all strength tests have been completed. For production units not in need of strength test, the weathertightness test is to be conducted at a reasonable stage during production.
4.3.5 Strength tests
(a) Strength tests are to be carried out as specified in Table 4 - 1 after the completion of all the work.
(b) Measurements are to be taken as required in Table4 -1 before, during and after applying test loads.Additional measurements may be required depending upon the circumstances.
(c) Upon completion of tests, containers are to reveal neither permanent deformation nor abnormality.
4.3.6 Strength tests with one door off operation
(a) Containers with one door removed have a significant reduction in their ability to withstand racking loads and, potentially, a reduction in stacking strength. The removal of a door on a container inoperation is considered a modification of the container. Containers must be approved for one door off operation. Such approval should be based on test results as set forth below.
(b) On successful completion of the stacking test the container may be rated for the allowable superimpo sed stacking mass, which should be indicated on the Safety Approval Plate immediately below line 5:
"ALLOWABLE STACKING LOAD ONE DOOR OFF FOR 1.8g (kg and lb)."
(c) On successful completion of the racking test the racking test load should be indicated on t he Safety Approval Plate immediately below line 6: "TRANSVERSE RACKING TEST FORCE ONE DOOR OFF (newtons)."
Table 4-1
Strength Tests for Containers (1/3)
Tests Test Procedures Measurements
Stacking
Internal loading: 1.8R-T(kg), uniformly distributed over the base.
Applied forces on containers of 1A, 1AA, 1B, 1BB, 1C and 1CC (values for containers of 1D are given in brackets): with the container in the normal position supported at the base corner fittings, comprehensive forces of 847kN (224 kN) to be aplied to each of the four top corner fitting simultaneously, or 1,693kN(448 kN) on each pair of end fittings.
These test forces are derived from thesuperimposed mass of nine-stacking
(six-stacking) i.e. eight (five) containers stacked on top of one container, all being rated 24,000kg (10,160kg) and acceleration force of 1.8g.
The test is to be repeated to cover for all positions of offset, namely 38 mm longitudinally and 25.4
Internal loading:2R-T (kg), uniformly distributed over the base.
The container is to be supported for 5 minutes.
(i) While loaded and supported by bottom corner fittings before lifting clear, the deflection at lowest points of bottom side rails and at the longitudinal center line of the base.
(ii) Any distress due to lifting.
(iii) Permanent set remaining on removal of the load.
Bottom lifting
Internal loading: 2R-T (kg), uniformly distributed over the base.
Applied forces: Lifting forces are to be applied gradually through the bottom corner fitting side apertures in direction to the horizontal as follows:
1A, 1AA 30
1B, 1BB 37
1C, 1CC 45
1D 60
The container is to be supported for 5 minutes.
Any distress due to lifting
Lifting from fork lift pockets
Internal loading:1.25R-T (kg), uniformly
distributed over the base. In case the container is fitted with an extra set of fork lift pockets, an additional test is required. A load of 0.625R-T (kg) is to be evenly distributed when lifting from the inner pockets.
Applied forces: The container is to be supported for 5 minutes by two bars, 200 mm wide, inserted to a depth of 1,828 3 mm in each set of fork pockets in turn.
Undue local distortion during the test and any permanent distortion.
Table 4-1
Strength Tests for Containers (2/3)
Tests Test Procedures Measurements
Lifting from grappler arm positions
Internal loading: 1.25R-T (kg), uniformly distributed over the base.
Applied forces: The container is to be supported by four grapler arm positions for 5 minutes. The area of suppport position is to be the same as the grappler arms intended to be used.
Undue local distortion during the test and any permanent distortion.
Floor strength
Internal loading: Nil
Applied forces: A vehicle (wheel centers 760 mm, wheel width 180 mm, maximum contact area per wheel 142 cm2 in the rectangular envelope of 185 mm wide, 100 mm long) loaded to an axle weight of 54.6 kN, 27.3 kN per wheel, is to bemaneuvered over the entire base area.
Deflection and permanent set in three locations of the base.
Side wall strength
Internal loading: 0.6 Pg (N), uniformly distributed over the wall under test.
Application: The container is to be supported in such a manner that the panel is free to deflect over the side wall and its top and bottom side rails.
Unless they are identical, both side walls are to be tested.
Deflection and permanent set at the center of the side wall and the center of the top and bottom side rails.
End wall strength
Internal loading: 0.4 Pg (N), uniformly distributed over the wall under test.
Application: The container is to be supported in such a manner that the panel is free to deflect over its entire surface. Unless they are identical, both end walls are to be tested.
Delfection and permanent set at the center and at least two other locations.
Roof strength
Internal loading: Nil.
Applied forces: 3 kN, uniformly distributed over an area of 600 mm300 mm at the weakest area of the roof.
Maximum deflection and permanent set of the section under test.
Internal loading: R-T (kg), uniformly distributed over the base.
Applied forces: The container is to be secured to
The change in length of both bottom side rails during and after the test in each direction.
Table 4-1
Strength Tests for Containers (3/3)
Tests Test Procedures Measurements
Longitudinal kN is to be applied to top corner fitting(s) on one end. The force is to be applied first toward then away from the container.
Note: Containers 1D need not be tested.
Longitudinal displacement of top side rails is not to exceed 25mm. bottom corner fittings: a transverse force of 150 kN is to be applied to top corner fitting(s) on one side.
The force is to be applied first toward then away from the container.
Note: Containers 1D need not be tested.
Difference in diagonals on one end is not to exceed 60 mm..
Cargo securing system test
Applied forces: The tensile force equal to 1.5 times the rated load is to be continuously applied at the specific angle for 5 minutes as follows:
Sceuring systems
installation Direction of applied forces at the floor
Perpendicularly to the axis of the container structural members 45° to the horizontal plane
above the floor 45° upwards and downwards from horizontal plane at the roof 45° downwards
A minimum rated loading for each anchor point is 10 kN and for each lashing points a minimum rated loading is 5 kN.
Notes:1.Anchor points are securing devices located
Notes:1.Anchor points are securing devices located