Title ISO floor test
Name Admin Date 2014-05-12
It has been confirmed again as a common saying to the fact that machine / material itself never tells a lie, however human can do it intentionally !

As we have been aware well of, MGW and floor test load have been up-graded since 2005 whereas the basic strength / material such as design of structural configuration, corner castings, floors have not been changed yet, in the meantime, the container price has been marginal in comparison with total raw material costs required per unit production shown on data diagram noted above, which can result from excessive competition by several container manufacturers in this field, is also inevitable for factories to cheat material quality, conceal the truth to save a cost, a kind of " Vicious circle " without being solved completely.

Nonetheless; nobody wants to be the first challenger to lead to go a right way so far, ignoring it under a wait & see policy only, but not highlighting in detail.
However, in case of owner for their fleets / asset; it's very essential for them to check the fact on the base of substantial analysis / tests in detail to protect their own assets to keep safety as a long-term view. ( containers are in general being utilized for max 15 years after having produced )

Materially, as the floor test load has been increased to 7,260 kgs from 5,560 kgs since 2005, it has been a worrisome / dubious as to whether ISO test can be passed or not without change of gooseneck tunnel structure even though it is very important for ISO dimension ( 120 mm +0, -3 mm ) for fitting of gooseneck chassis and its strength ( its thickness is 4 mm in general with tunnel bows ( 4.5 mm t ).
For which ISO/TC 104 has issued ISO/TR 15070 in 2005 when ISO 1496-1,2 coincidently has amended its test load to 7,260 kgs, however containers' factories / class used to conceal the fact intentionally by adjustment of test vehicle weight under very sneaky idea.

eg., to divide the test load, 7,260 kgs by one fourth, factory insert several pcs of steel plate into the pads of auxiliary small wheels installed on the main test vehicle to let them keep the same level as the main big wheels, whose role have to be only safety for feasible falling down of the main test vehicle without being it touched onto the wooden floor during floor testing.

As we are aware well of this:

  inserted steel plates intentionally to let small wheels touch on the floor to share the truck weight ( 7,260 kgs ) by total 4 whereas it stipulates to do by 2 wheels in ISO.

 steel plates taken out

   Non-touch on the face of floor during testing after modification

Frankly, we are a job police to protect owner's asset so that we have to more smart than factory to detect problem to warn them not to cheat, if not, it's a scare crow;
Anyhow, it's similar conception in society; to catch a thief; 10 watchdogs are not enough sometimes due to focus mind is different each other !!!

Substantially; our esteem / reasonable client tested the floor closely to recognize the fact at different factories applying by the same spec / design pursuant to new ISO standard, ISO/TR 15070 & ISO 1496-1; as a result; both are failed, which means; considering floor test by 7,260 kgs performed at different factories under the current design ( 4.0 mm t tunnel plate + 12 pcs of Tunnel bows; we can conclude that the floor test can't be passed frankly regardless of test sequence pursuant to ISO /TR 15070 and 1496-1 unless otherwise manufacturers cheats owners by test tools and sneaky way.

As a back-up data:

ISO Dimension standard ( H2) : 120 mm + 0 mm, - 3 mm

Before test: 197 mm during 167, 165 mm ( deflection: 30 mm, 32 mm ), after 188 mm = 9 mm against 5 mm required in ISO, which was at the check point of the tunnel bow located by 200 cm away from the front of Gooseneck tunnel plate ( ISO check point ) where the fork lift wheels are stopped with cargoes actually into the container during handling.


To keep strength safety of their own asset ( container ) and pass ISO rule and economical investment; they took an idea out as a countermeasure with modification of the design as below:

♣ 1st step: to analyze cost increase in case of change to 4.5 mm t or 5.0 mm t of the tunnel plate and adding of 1 more tunnel bow:

                         Thickness: 4.0mm
                         Tunnel bow: 45”hc from 16 to 17 pieces
                         40’GP & 40’HC from 12 to 13 pieces

Cost comparison table:
In case of 4.0 mm thickness ( most current design ):
40': goose-neck tunnel plate:
4.0 mm t x ( 40+25+50+1029+50+25+40) x 3315 x 7.85 x 0.62 ( $620 per ton for corten ) ÷ 1,000,000 = $81.251
tunnel bow:
{ 4.5 mm x ( 26+26+100 ) x 1029 x 7.85 x 0.62 } ÷ 1,000,000 =$3.425 x 12 pcs=$41.1

In case of 4.5 mm t =$91.407 ( abt $10 ↑↑) ( Gooseneck tunnel plate ),
In case of 5.0 mm t=$101.564 ( abt $20↑↑ ) ( Goose-neck tunnel plate )

In addition: in case of 1 more tunnel bow adding only:
{ 4.5 mm x ( 26+26+100 ) x 1029 x 7.85 x 0.62 } ÷ 1,000,000 =$3.425

♣ 2nd step: to minimize production cost investment and maximize optimum strength; did we perform a simulation displacement as attached:
Ēš12 pcs : 27.13 mm deformed Ēš 13 pcs: 23.92 mm deformed
Thus, 13 pcs of T/B type can be more enhanced by 3.21 mm ( 195 mm pitch betw T/B at 2 meters area from the front ) than 12 pcs.

1. 12 PCS tunnel bow (Displacement max 27.13 mm)

2. 13 PCS tunnel bow (Displacement max 23.92 mm)

 On the basis of simulation result; they reviewed it carefully / logically, as a result,6 mm or, 8 mm or 9 mm deformed during testing - 3.21 mm = 5.79 mm, which can be marginal for ISO standard.

♣ 3rd step: 
On the base of test results, reviewing of several factors involved and technical analysis; finally to add 1 more tunnel bow ( from 12 pcs to 13 pcs total ) adjacent load concentrated zone ( 2 meters away from the front ), each tunnel bow pitch : 190 ~ 195 mm against the old one: 215~250 mm ).
In addition, 1 more gusset each to wide flange of outrigger.

♣♣♣ In addition; ISO test is for just reference of design / strength view; however; CSC stipulation is mandatory for safety so that any factory has to be essential always.

CSC 2013

++++++++++++++++++++++++++++Reported by Henry Kim+++++++++++

" a bird who wake up early can eat more worms , fly longer & further to find another a new sphere to cultivate it earlier than any of others, under which he can afford to prepare everything in advance without hastening and think a good idea prior to their reaching " ..................