OPEI FUEL LINE

PERMEATION TEST RESULTS

DATE:  APRIL 12, 2006

Test Summary

Nine NBR fuel lines were submitted for permeation testing using the EPA
test temperature (23°C) and test fuel (E10).  The nine fuel lines
supplied from three major handheld equipment manufacturers consisted of
both molded fuel lines and lines cut from large spools or reel stock. 
The fuel lines were pre-soaked in E10 fuel at room temperature for a
minimum of 30 days.  The fuel lines were tested for permeation using
fresh fuel and following the general guidelines of SAE J30 (weight loss
test).  

The average permeation rate for all nine fuel lines is 253.59 g/m2/day
with the highest line at 454.73 g/m2/day, the lowest at 164.91 g/m2/day
and the median being 198.06 g/m2/day.   

Test Instrumentation

Sexton Escep walk-in environmental test chamber.

Sartoris electronic balance (0.01 gram resolution).

Test Procedure

The fuel lines were joined end-to-end and connected to a 1 gallon sealed
fuel can, filled with E10 fuel.  Fuel was pumped through the lines to
ensure all air was removed and the lines were allowed to condition for a
minimum of 30 days at room temperature.  Approximately every 5 days the
fuel was pumped through the lines to ensure fresh fuel was always in
contact with the lines during the soak period.

Upon completion of pre-soak the individual lines were attached to
individual fuel reservoirs containing fresh E10 fuel.  The connections
for the fuel lines to the reservoirs were similar to the fittings used
in the production applications for these fuel lines.  An initial
permeation test was performed to determine the needed fuel line length
in order to accurately measure the permeation rate.  The fuel line
length was either lengthened or shortened in order to achieve permeation
rates that the electronic scale could accurately read.  Prior to the
final permeation test, fresh fuel was replaced in the reservoirs and the
lines and reservoirs were allowed to stabilize at 23°C for 4 hours. 
Each reservoir/line was measured for weight loss every 24 hours ±0.5
hours.  After each weight measurement the reservoir and line were
inverted to drain the fuel from the line and then returned to the line
down position to refill the line with new fuel.  The lines were tapped
to ensure air bubbles were displaced from the fuel line.  

The permeation rate was calculated based on the individual line length
and the manufactures reported line ID dimension.  A running calculation
of the cumulative weight loss showed that after five days of measurement
the R2 value exceeded 0.99 and the test was considered accurate and
complete.

Test Results

The test data is shown in both text and graphical form in the below
Excel file.

  HYPERLINK "OPEI%20Fuel%20Line%20Test%2023C%20Test%20Report.xls"  OPEI
Fuel Line Test 23C Test Report.xls 

 

 

Conclusions

The average permeation rate for the nine fuel lines is 253.59 g/m2/day. 
The highest permeation rate was 454.73 g/m2/day while the lowest rate
was 164.91 g/m2/day with the median being 198.06 g/m2/day.  

The two molded fuel lines were 198.06 and 386.08 g/m2/day respectively
with an average of 292.07 g/m2/day.  

The seven lines from reel stock averaged 244.03 g/m2/day with the
highest being 454.73 g/m2/day and the lowest being 164.91 g/m2/day with
the median at 191.50 g/m2/day.

The average permeation rate for the nine lines is 36.6% below the EPA
estimated rate of 400 g/m2/day.

