Club of bologna proceedings

Tractors
- Some of the testing procedures 
of the National test for tractors are 
common with those of the OECD test. 
Therefore, certain test items can be 

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omitted if the tractor has already been 
tested with the OECD test code, and the 
test results of the OECD test can be 
substituted for those of the National test. 
This reduces the burden on the applicant 
and facilitates the trade of agricultural 
machinery. However, the National and 
OECD test codes are not perfectly in 
accord, and the National test includes 
certain unique test items which are not 
regulated by the OECD test (
Table 4
).
At present, certain durability tests are not 
included in the National test because the 
performance of engines and transmission 
systems has been previously established, 
and in this way the time spent on testing is 
reduced. Likewise, drawbar performance 
tests with additional weight are not 
included in the National test because the 
measurement without additional ballast 
can provide a rough prediction of 
performance with additional ballast.
The waterproofing test is one of the tests 
that is unique to Japan. Because tractors in 
Japan are normally used in paddy fields, 
the countermeasure preventing water from 
entering a machine is an important tractor 
performance parameter. In this test, the 
tractor is operated for two hours on the 
bench, inside a water bin with soil, after 
which the tractor axle group is 
disassembled and inspected to determine 
the amount of water penetration. 
A durability test on continuous operation 
of the power lift is carried out, in 
consideration of the high frequency of use 
of the power lift device due to the narrow 
fields in Japan.