Thu, Dec 9th 2010, 12:43 by Indresh Mathur
At Haltermann Solutions, we strive to meet our customers’ needs and expectations. This process starts with our customer submitting a custom fuel specification sheet http://haltermannsolutions.com/pdf/custom_fuel_request_form.pdf which can be accomplished by submitting the request on-line or by downloading a custom fuel specification sheet and submitting it at the customer’s convenience. This step formally starts the development process to develop a fuel that would meet the desired performance expectations while ensuring our capability to produce the fuel reliably. The next step entails a dialogue with our customer to ensure that the desired specification has taken into account the precision and repeatability (r) of the analytical method used to measure a given specification parameter, the reproducibility (R) among different labs measuring the same parameter and the variability inherent in manufacturing numerous blends of the same fuel.
In an effort to describe the importance of proper specification limits, we have given an example below:
We were asked by one of our customers to formulate a fuel as shown in the specifications given in the attached table. If we had agreed to manufacture this fuel and accepted the specifications proposed by this customer, there would have been a good likelihood that we would not have been able to meet our customer’s needs a percentage of the time. This would happen either because a) certain analytical methods were not precise enough to measure a given parameter or b) the minimum and maximum values expected by the customer were outside the variability of the measurement and the variation of the manufacturing process. To prove our point to the customer, we produced four samples of this fuel in our lab under controlled conditions (manufacturing scale would present additional challenges and variation). Sixteen samples of the same fuel were sent out to 4 different analytical laboratories. Blind analysis (i.e. no specifications or targets provided to the analytical lab) was performed to ensure there was no bias in the results.
Data and results are given below. Statistical analysis was performed on the lab results of the analytical data compiled. You will notice that some parameters proposed by the customer for this fuel were outside the minimum / maximum range predicted by our data or the reported ASTM reproducibility (R) for those methods. These are highlighted in pink color on the attached table. You will also notice that one of the specification parameters (MTBE content) was requested at 0.05%, maximum, whereas the detection limit for the analytical method is 0.2%.
We hope this example has demonstrated to you the importance of proper specification development. We will make every attempt to resolve these issues during our dialog with you regarding your new custom fuel requests. We want to meet your needs but only within our manufacturing and analytical capability to do so.
Click on the table below to view PDF file