Controlling Contamination with Fuel System Filtration: A Case Study

Edgar Gutierrez, Ademinsa


Since installation of the microfiltration system
in the loading shovel’s diesel tank, its
condition and operation have
met all expectations.

When a mining company in Peru performed a field inspection on the microfilters of one of its loading shovels, its goal was to determine the ISO code level and to check for visible particles. At the time of the inspection, the microfiltration system had been in operation less than 1,000 hours, while the loading shovel was reported to have less than 5,000 hours of operation.

During the inspection, the hoses to the fuel tank were checked to verify that they had not been grazed or cut with a cutting element. The microfilter cap was cleaned and then slowly removed, making sure there was no fuel leakage. One filter cartridge was carefully taken out of each unit. From the bottom of the filter containers, fuel residue was removed.


The hoses to the fuel tank were inspected to verify that they had not been grazed or cut.

Two cartridges were visually inspected in the field with the upper surface of the microfilters examined to detect the presence of trapped visible particles. In order to evaluate the particles with a microscope and to identify the origin of these solid contaminants, the two used filter cartridges were sent to the Yanacocha laboratory.

 


The exterior of the microfilters showed
powder impregnation as the
result of operation.

New filter cartridges were then installed with new seals placed on the edges of the caps to prevent any fuel leakage. The caps were manually adjusted up to 70 pounds and aligned with the seals in the right position. After the loading shovel was turned on, the microfiltration unit and accessories were inspected in operation to verify that there were no fuel leaks.

 

Inspection Results

Before the filter cartridges were changed, the microfiltration unit was observed under normal operating conditions. The exterior of the microfilters showed powder impregnation as the result of operation. The microfilter unit was found to be correctly installed and adjusted to the loading shovel. The hoses, connectors, protective metal frame, etc., were all in good condition, and the onboard particle counter was operating properly.


When the microfilters were changed, a dark
color was noticed in the filter cartridges along
with visible particles on the surface.

While the microfilters were being changed, a dark color was noticed in the filter cartridges along with visible particles on the surface. In the bottom of the filter containers, some diesel fuel was discovered that was clean and dry.

After the microfilters were changed and the caps were sealed, the loading shovel was turned on, and the microfiltration unit showed no signs of diesel fuel leakage. When the two used filter cartridges were weighed at the Yanacocha laboratory, it was confirmed that both used microfilter elements had a greater weight concentration of pollutants in comparison to a new filter element.

Solid particles were removed from the microfilters and analyzed at the laboratory. An additional particle analysis was performed to determine the origin of the particles larger than 40 microns trapped in the filter cartridges.

When the diesel fuel was examined in the loading shovel, the ISO code level of the fuel that reached the diesel tank after microfiltration was determined to be ISO 17/15/14. This met the requirements stipulated by the engine manufacturer for diesel fuel B5.


Fuel residue was removed from the bottom of the filter containers.

In the laboratory, tests were performed on diesel fuel samples that were taken on two different days. The final results showed the cleanliness level was ISO 15/12.

Conclusions

Since installation of the microfiltration system in the loading shovel’s diesel tank, its condition and operation have met all expectations, confirming the system’s effectiveness and efficiency. The filters capably remove contaminants, significantly reducing the risk of wear for the pumps and injectors.


New filter cartridges were installed with new seals placed on the edges
of the caps to prevent fuel leakage.

Diesel fuel entering the microfiltration unit is pulled from two separate points located at the bottom of the tank, preventing the accumulation of “hidden” water, sediments and contaminants that affect the daily refill of clean diesel fuel. The diesel fuel in the shovel is maintained at an ISO code level of 17/15/14 (or less in continuous operation).

It is important to note that when the fuel level in the tank is low, the number of times microfiltration is performed on the remaining fuel in the tank increases, ensuring the cleanliness of the fuel in the bottom of the tank and preventing accumulation of sediment, particles and water. This also guarantees constant cleaning of the fuel tank during continuous operation of the loading shovel.

Subscribe to Machinery Lubrication

About the Author