SEAL 9U8141 - Caterpillar

Filter Housing
Fluid filter housings, also called cans, are typically of metallic construction. Cat filter housings are high quality metallic one piece design. The filter housings are of optimal material thickness in order to withstand the pressure of fluid flow. Cat filter housings provide structural strength and anti rupture protection. Cat filter housings are constructed with precision threading to prevent leaks and to prevent unthreading due to vehicle vibrations and operation. The housings precisely fit onto the filter base to prevent leaks and ingress of contamination. Instructions on the assembly of the filter are printed on the filter housing. The housing may or may not be reused depending on the filter design
The housing of a spin-on type filter contains the filter element as an integral part. This unit of housing and element are changed at every maintenance interval. Spin-on filter housings may display the filter part number and identification as well as critical assembly information in order to ensure proper maintenance practices.
The housing of a cartridge type filter is separate from the filter element. At maintenance intervals, only the filter element is changed and the housing is reassembled on the machine with the new filter element.Details of these two types of filters are discussed later in this Special Publication.Filter Media
The media is responsible for capturing contaminants in the fluid. Filter media can be made of natural material such as cellulose, synthetic material such as glass fibers, or of a combination of natural and synthetic material. Media material can also be filled or impregnated with custom materials such as glass or resins to enhance strength and durability. Cat filter media is high-quality media and can be multiple layers with varying efficiencies for each layer, or one layer that is thick for increased depth filtration.Cat filter media is of high quality. The media of Cat filters is of optimized thickness and area to withstand the fluid pressures and flows designed into Cat engines and compartments. The media material quality and construction allows the filter to resist flow spikes, cold start pressures, and extreme temperatures of the fluid. Cat filter media does not shed materials that add undesirable contamination into the fluid. The total area of the filter media is designed to capture the appropriate level of contamination for the designed life of the filter with specified system cleanliness. A note of importance is that the pores in the filter media are not uniform in size or in shape. As a result filters can be designed so that particles of various shapes and sizes can be captured or allowed to pass through the filter if desired.Filter media is typically pleated to add surface area for effective filtration and service life. Pleating quality and density of the filter media is essential to the durability, structural integrity, and ability to remove contamination. The pleats should be equally spaced and densely constructed. The pleats in Cat filters are stabilized to eliminate bunching, to preserve the pleats spacing and to hold contaminants even under engine or