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UNITIZED CARGO

1. GENERAL PROVISION ^

The purpose of this standard is to provide a national guide to unitized cargo requirements, and is applicable only to cargo units being lifted by banding.

1. Approval of banding material and unitizing methods may be obtained by application to the Regional Manager, Coast Guard Ship Safety, for your area.
   Approval will be granted on the basis of satisfactory tests.
   
   
2. It should be noted that the actual unitizing of cargo, once the method Is approved, Is not done under inspection, but that the responsibility for the observance of the required standards, the making of tests and adherence to good quality control, rests with the person offering for shipment such goods, so unitized.

The materials addressed in this standard are flat steel strapping, and wire.

4. FLAT STRAPPING UNITIZING SYSTEMS ^

1. These systems consist of the automatic machine or hand tool methods of applying and sealing the banding, the banding material and seals, and the lifting arrangement.
   
   
2. Each manufacturer of flat strapping must obtain approval for his particular strapping and seals, lifting gear, method of unitizing by strapping, and in conjunction with any necessary lifting gear, the method of lifting must be approved.
   
   
3. A list of suppliers of unitizing strapping who have obtained approval for their material is shown in Appendix I.
   
   
4. A list of approved units is shown in Appendix II.

1. A mill certificate is to be supplied with the strapping.
   
   
2. The coils are to be numbered and referenced by that number on the mill certificate.
   
   
3. The mill certificate should show at least the following:
   
   
   1. Identifying number of each coil, or an identifying quality stamp mark,
      
      
   2. Width and thickness of the strapping,
      
      
   3. If coated, the type of coating,
      
      
   4. Ultimate tensile strength.
      
      
4. It is preferable that the figure for ultimate strength be simply that for the strapping as is, rather than be shown as the value per square inch of material.
   
   
5. It is the responsibility of the person using the strapping to check that each coil is referenced on the mill certificate and is adequate for the intended use.

6. SEALS ^

1. The type, number fitted, and number of crimps per seal, are to be as directed by the supplier of the strapping.
   
   
2. The ductility of the strapping must be sufficient to accept the seal crimp, without cracking.

7. EQUIPMENT COMPATABILITY ^

1. The strap tensioning gear, seals, and crimper, as well as the strap itself, if from the same supplier, are accepted as being compatible.
   
   
2. Where seals or strapping or equipment are not from the same supplier, the user Is to obtain written assurance from the different suppliers that the intended combination is a compatible one.
   
   
3. Independent testing by a competent person, to establish compatibility, may be used to resolve impasses.

The strength of the joints is to be established by testing.

9. TEST FREQUENCY ^

1. The schedule of tests for flat strapping is to be not less than one per 300 units strapped.
   
   
2. An alternate test program which has been authorized by the Department is one test per 1000 tons of pulp strapped, but not less than three tests per consignment.
   
   
3. The above tests are for checking the satisfactory operation of the equipment during the production run, and are additional to any tests necessary to ensure the equipment is operating properly following modifications, repairs or prolonged shutdown of the equipment.
   
   
4. A similar test frequency is to be employed on any pulp restrapped subsequent to poor test results, or damage to original strapping.
   
   
5. It must be noted that complying with the above test schedule does not relieve the person or mill strapping the unit from the responsibility of ensuring that all seals and strapping are properly put on.

1. A record of tests is to be retained at the establishment where the cargo was unitized and must be signed by the person doing or supervising the testing.
   
   
2. The test record and the units covered by the sample testing are to be identifiable one to the other by an identifying number.

11. TEST CERTIFICATE ^

A test certificate similar to that shown in Appendix Ill shall be prepared by the person responsible for the unitizing of the cargo, and a copy of the certificate shall accompany the units.

12. TEST EQUIPMENT ^

1. The sealed joints to be tested may be pulled by a firm engaged in testing materials and their certificate constitutes the record of tests.
   
   
2. The establishment doing the unitizing may make the tests themselves provided their pulling machine has been calibrated, to ensure its accuracy.
   
   
   The testing equipment at such an establishment may be either a unit to measure the ultimate tensile strength of the piece tested, or alternatively a unit that applies a limited certain force, such that the material tested is shown to be capable of withstanding the tensile load for which the machine is set.
   
   
   Where the testing apparatus is of the latter type, and so that no misunderstanding occurs as to the setting of the machine, a notice shall be attached to the machine indicating its tensile setting, or alternatively, the setting may be referenced to the unit weight for which it is set up.

1. All units banded for single lift purposes must be so banded as to provide a minimum safety factor on the strapping of 3.5:1. All units banded for multiple lift purposes, by which it is permitted to lift the unit on four separate occasions, must be so banded as to provide a minimum safety factor on the strapping of 4:1.
   
2. Other than in special cases, all units whether basket handle type or single band type or any variations of the same, are to be banded to provide for a bridle angle of 40 degrees. The minimum strength of the banding shall therefore be:-
   
   Safety Factor X Half Weight of Unit X Secant of Bridle Angle
   
   The bridle angle referred to is that angle contained between the vertical and the maximum allowable angular departure of the strapping from the vertical under the lift conditions, that is to say it is the angle at one of the top corners of the unit, contained between the vertical and the lifting strap.
   
   
3. A special strapping case in point, is that of units specifically designed for a vertical condition of the strapping during lifting, and so lifted, whereby no need arises to make provision for bridle effect.
   
4. In addition to the above, banding used for multiple lift unitizing shall be of such a nature as to adequately withstand exposure of the material during its intended service life.

14. JOINT LOCATION AND EFFICIENCY ^

Where the seals on the strapping of a flat band type unit, are located on the bottom of the unit, and thus projected by friction from the full lifting stress, and where such sealed joint provides not less than 90% of the strapping strength, then the straight line strapping strength as indicated on the mill certificate may be used in establishing the required banding strength.

Where the seals are on the side or top of the unit, the banding strength shall be taken to be the sealed joint strength.

1. It should be noted that where strapping has a safety factor of 3.5:1, and the unit is therefore only permitted to be lifted on one occasion by its strapping, then that lift shall be from the dock into its final position in the ship. Other lifting methods must be used for all other occasions.
   
   
2. Banding to be in virtually new condition at time of first use.
   
   
3. Units awaiting shipment to be reasonably protected.
   
   
4. Only approved lifting gear should be used on the strapping.
   
   
5. The lifting hooks and the lifting band should fall reasonably within the same vertical plane.

A Regional Manager may authorize the modifying of the lifting band from a basket handle type to a single band type, provided:-

1. A check is made in all cases where this is to be done, that the existing strapping is sufficiently strong to accommodate the increased stress due to the bridle effect.
   
   
2. A representative joint is tested at the beginning of the operation to ensure that an adequate joint is being made.
   
   
3. The same schedule of tests as set out for new units is to be observed.
   
   
4. Repaired units are identified in the record of tests.
   
   
5. Repaired units are rated for single lift only.

1. The systems consist of the wire applying machine, wire used, and lifting arrangement.
   
   
2. Each manufacturer of round wire banding must obtain approval for his particular wire, method of knotting the wire, lifting gear, method of unitizing by wire banding, and in conjunction with any necessary lifting gear, the method of lifting must be approved.
   
   
3. A list of suppliers of unitizing wire who have obtained approval for their material is shown in Appendix I.
   
   
4. A list of approved units is shown in Appendix II.

1. A mill certificate is to accompany all wire used in unitizing.
   
   
2. Each coil of wire is to be identifiable to the mill certificate.
   
   
3. The mill certificate should show at least the following:
   
   
   1. Identifying number of each coil,
      
      
   2. Diameter of wire,
      
      
   3. Straight line breaking strength.
      
      
   4. Knotted breaking load, or alternatively the elongation in a 10" test piece.
      
      
4. The elongation in such a test piece is not to be less than 7%.
   
   
5. It is the responsibility of the person using the wire to check that each coil is referenced on the mill certificate and is adequate for the intended use.

1. The wire applying equipment as well as the wire itself, if from the same supplier, are accepted as being compatible.
   
   
2. Where equipment and wire are from different suppliers, the user is to obtain written assurance from both suppliers, that the combination of wire and equipment being used, is compatible.
   
   
3. Independent testing by a competent person, to establish comparability, may be used to resolve impasses.

The schedule of tests for round wire banding is one test of the straight wire, and one test of the wire in the knotted condition every time the coil is changed; and in addition one test of the wire in the knotted condition each shift (a shift is considered to be eight hours of production run).

1. In the manufacture of the wire used in unitizing, there is a variation of tensile strength from about 140,000 PSI to 160,000 PSI, and a variation in diameter of ±.0015". The minimum strength for the gauge size will be stipulated by the company doing the unitizing, and shall be the strength allowed in determining the number of wires required on the unit, thus variations in wire used in unitizing, will result in the wire having a higher breaking strain than the stipulated minimum.
   
   
2. The knotted efficiency is to be not less than 90% of the stipulated minimum, thus where wire is in fact somewhat stronger than the stated minimum, the joint efficiency may be less than 90% of the actual wire strength.
   
   
3. Where at any time joint efficiency is found to have dropped below the required minimum, the supplier of the wire and knotting equipment should be immediately notified.
   
   
4. Where a slight decrease in joint efficiency is discovered and fully compensated for by fitting additional wires to all units covered by the representative test, then the fact that such compensation has been made in the banding should be recorded in the test record.

22. TEST RECORDS ^

1. A record of tests is to be retained at the establishment where the cargo was unitized, and must be signed by the person doing or supervising the testing.
   
   
2. The test record and the units covered by the sample testing are to be identifiable one to the other by an identifying number.

A test certificate similar to that shown in Appendix III shall be prepared by the person responsible for the unitizing of the cargo, and a copy of the certificate shall accompany the units.

1. The wire and knot tests required, may be done by a firm engaged in testing materials and their certificate constitutes the record of tests.
   
   
2. The establishment doing the unitizing may make the test themselves provided their pulling machine has been calibrated, to ensure its accuracy.
   
   
3. The testing equipment at such an establishment may be either a unit to measure the ultimate tensile strength of the piece tested or alternatively a unit that applies a limited certain force, such that the material tested is shown to be capable of withstanding the tensile load for which the machine is set.
   
   Where testing apparatus is of the latter type and so that no misunderstanding occurs as to the setting of the machine, a notice shall be attached to the machine indicating its tensile setting or alternatively the setting may be referenced to the unit weight and number of wires for which it is set up.

1. All units banded for single lift purposes must be so banded as to provide a minimum safety factor oh the banding of 3.5:1.
   
   
2. All units banded for multiple lift purposes, by which it is permitted to lift the units on four separate occasions, must be so banded as to provide a minimum safety factor on the banding of 4:1.
   
   
3. It must be particularly noted that in the case of several strands of wire forming the lifting band, that it is essential that all be evenly tensioned.
   
   
4. Other than in special cases, all wire banded units are to be banded to provide for a bridle angle of 40°. The minimum strength of the banding shall therefore be:-
   
   Safety Factor X Half Weight of Unit X Secant of Bridle Angle
   
   The bridle angle referred to is that angle contained between the vertical and the maximum allowable angular departure of the wire banding from the vertical under the lift conditions, that is to say it is the angle at one of the top corners of the unit, contained between the vertical and the lifting band.
   
   
5. A special banding case in point, is that of units specifically designed for a vertical condition of the banding during lifting, and so lifted, whereby no need arises to make provision for bridle effect.
   
   
6. In addition to the above, banding used for multiple lift unitizing shall be of such a nature as to adequately withstand exposure of the material during its intended service life.

26. JOINT LOCATION AND EFFICIENCY ^

Where the banding wire knots are located on the bottom of the unit, and where such knots provide not less than 90% of the required minimum strength of the wire, then the straight line stipulated minimum strength of the wire as called for by the unitizer’s specification, may be used in establishing the required banding strength.

1. It should be noted that where banding has a safety factor of 3.5:1, and the unit is therefore only permitted to be lifted on one occasion by its banding, then that lift shall be from the dock into its final position in the ship. Other lifting methods must be used for all other occasions.
   
   
2. Banding to be in virtually new condition at time of first use.
   
   
3. Units awaiting shipment to be reasonably protected.
   
   
4. Only approved lifting gear should be used on the banding.
   
   
5. The lifting hooks and the lifting band should fall reasonably within the same vertical plane.

THE REMAINING SECTIONS APPLY TO BOTH WIRE AND FLAT BAND

1. In any instance where cargo unitized with flat strap or wire of a particular manufacturer, is to be lifted with gear other than that originally approved for the banding in question, then to establish that such combination of banding and lifting hook is compatible, a test consisting of not less than 20 sequential lifts with the banding in a 100% overload condition shall be made.
   
   Where no damage occurs to either the banding or lifting hook, as a result of the test, the combination will be considered a safety arrangement.
2. In the instance of tests relating to the use of lifting gear for multiple lift purposes, a sample of the banding in way of the lifting hook its to be tested to destruction with no significant reduction in tensile strength being noted.

1. The method of combining the individual parts into a shipping unit shall produce a stable unit with high package strength. This package strength and stability may be:-
   
   1. Inherent - e.g. plywood or lumber units.
      
      
   2. Compact - e.g. cubic paper pulp bales with a taut encircling band.
      
      
   3. Locked - e.g. round paper rolls, with strapping so interlocked as to prevent escape of individual parts.
      
      
2. The unit, ideally, should be able to withstand compression in stowage and rough handling to the extent that failure of the strapping shall occur before disintegration of the unit due to lack of packaging stability.

1.  
   1. Fatigue Test - Four units of cargo to be prepared. Banding to give a safety factor of 4:1.
      
      Samples of the banding in way of the lifting hooks will be taken at intervals of 4 lifts, 10 lifts, 20 lifts and 50 lifts.
      
      These samples will be tested to destruction, along with a sample of unused banding; no significant deterioration of the banding shall occur over the series of lifts - maximum loss 15%.
      
      
   2. Abrasion Test - Bottom: Unit moved a distance of 6 feet across horizontal concrete surface.
      
      Corner: Unit moved a distance of 3 feet up 7° sloping concrete surface.
      
      
   3. Impact Test - Unit drawn 18" out of vertical, then allowed to swing freely back the 18" to contact edge of 3/8" plate. Impact to be in way of banding. The edge of the plate may be hammer dressed.
      
      
   4. Hang Test - Unit shall be lifted and remain suspended for a period of four (4) minutes.
      
      
2. Test pieces for all tests to be taken in way of resulting areas of damage or deformation. The test results to show no significant deterioration - maximum loss 15%.
   
   
3. In addition to the above, banding used for multiple lift unitizing shall be of such a nature as to adequately withstand exposure of the material during its intended service life.

31. CONDITIONS RELATING TO MULTIPLE LIFT UNITS ^

1. Each approval applies only to the system tested.
   
   
2. The safety factor on the banding to be not less than 4:1.
   
   
3. The maximum number of lifts of the subject unit by its lifting band shall not exceed four lifts.
   
   
4. The duration of any lift shall not exceed four minutes. This is to avoid excessive transportation of the unit by its banding.
   
   Where however, in cargo processes, circumstances cause the duration of the lift to exceed the above limitation in order to accommodate practical requirements, then the actual duration of the lift shall constitute the permitted duration.
   
   
5. The interval between the first and the last occasion on which the unit is lifted by its banding shall not exceed four months.
   
   
6. A test certificate relating to the subject units, and similar to that shown in Appendix III, must always accompany the shipment.
   
   This certificate shall in addition to attesting to the quality of the banding, and identifying the units to which it relates, show the lifting history.
   
   
7. Stevedores are to be advised to exercise particular care in any secondary handling of multiple lift units, in accordance with the provision of the Tackle Regulations.
   
   This provision is as follows:
   
   "Except in an emergency, no worker shall be required to work with or in proximity to goods which are dangerous to life or health by reason of their nature or condition unless all precautions have been taken to safeguard the workers, and to advise them of the conditions existing."
   
   The above condition is required to offset any hazard due to the uncertainty of the condition of the slings after a sea voyage.
   
   The Master of the vessel which is to discharge such units, or the shipper of cargo or his agent, where reloading of such units is to occur, shall advise the stevedores accordingly.

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