TM 55-2200-001-12
Change 3
Section No. 1--General Rules (Rev.-9-1984)
(10)
Constant Tensioning Devices For Use With High Tension Bands Performance. Testing And Approval.
A. Performance
1.
Design of Device
(a)
To provide prescribed tensioning.
(b)
Quick and positive release, when provided.
(c)
Operate satisfactorily under all weather conditions.
(d)
Component parts must not seize because of rust or deformation.
(e)
Compression units, non metallic type, to be operable to -40F and not susceptible to deterioration because
of weather temperatures between -40F and 200F and sunlight radiation.
(f)
Point of band attachment to allow 10" angling laterally when applied to car.
2.
Accept bands up to 2 in. x .065 in., or other sizes as specified for the device.
3.
Have a locking feature that will not release under vibration or shock, but only when desired by operator.
4.
Compression unit to absorb 3,000 lbs. band compression and still have reserve travel for an additional 3,000 lbs.
compression.
5.
Attachment to car
(a)
Easy
(b)
Renewable
(c)
Attachment must be a minimum of equal strength of device.
(d)
No parts of device to exceed clearance outline in either locked or unlocked position.
(e)
Must not have parts susceptible to dragging when not In use.
B. Testing
1.
Complete device to be submitted to static testing equal to 1.5 times the breaking strength of the band size for
which it is designed.
2.
Complete device to be submitted to dynamic testing equal to the breaking strength of the band size to which It is
designed cycled 100 times in one hour.
3.
Under the above testing, no component part or the complete device is to have a failure or deformation in order to
be considered acceptable.
4.
Three complete devices must be tested in accordance with testing listed above, and all must pass the testing
successfully.
5.
Test may be conducted by the AAR Research Center or an Independent Certified Testing Laboratory. Test
conducted by the manufacturer will not be considered acceptable.
6.
Breaking strength values for the high tension bands used in testing of devices. are to be as published in General
Rule 15(J), Section No. 1 of the Open Top Loading Rules Manual.
C. Approval
1.
Devices that have passed the testing procedure successfully and comply with the performance requirement will
be submitted to the AAR Open Top Loading Rules Committee with all pertinent documents for evaluation.
2.
Successful passing of testing requirements will not automatically constitute approval of the device. The
Committee may request over-the-road testing of a specific number of devices and a defined number of loads
before granting approval.
3.
The Committee will either approve the device or return the submission to proponent explaining reasons for not
granting approval. Resubmission by the proponent will receive due consideration of the Committee.
4.
Upon granting approval, the device, model number, or other identification and name of manufacturer will be
published in General Rule 15(J)(11), Section No. 1 of the Open Top Loading Rules Manual, listing approved
"Constant Tensioning Devices".
D-32
