Filtran Continues to Optimize Technology

Filtration helps improve transmission life by minimizing wear, protecting against contaminants and preventing sticking and scoring of sensitive shift control valves

For the all-new Ford/ GM 10-speed RWD transmission, Tier 1 supplier Filtran designed a very special filter module. Instead of using an additional pressure filter to separate small-sized critical particles, the required fine filter media is placed on the suction side of the pump, integrated into the sump filter. The system integrates several features, which provide high levels of filtration efficiency, dirt hold capacity and pressure differential for the filter’s entire lifetime. The filter media is pleated to increase the effective area in relation to pressure drop and particle capture capacity. A medium-efficiency filtration media, with lower pressure differential, is placed parallel to the highly efficient media (with a naturally higher pressure differential), to enable parallel flow. The flow path of the medium-efficiency media is activated by a flow control valve, which has a flap valve design, depending on the pressure.filtran-combined

 

While the oil is allowed to bypass the fine media over the more coarse media in cold conditions, nearly all the flow has to run through the fine filter media at warmer temperatures.

Filtran has used a laser-welded housing. Laser-welding technology provides high strength and avoids residual contamination during manufacture, which is often a problem with alternative welding procedures such as friction welding. This innovative concept ensures outstanding filter performance, which is needed to protect the sensitive parts inside modern transmissions. This is particularly applicable for the directly controlled valves inside the transmission control units, but also for other components such as clutch plates and pumps, which must be protected by relevant filtration.

filtran-image-7

While the oil is allowed to bypass the fine media over the more coarse media in cold conditions, nearly all the flow has to run through the fine filter media at warmer temperatures.

Filtran has used a laser-welded housing. Laser-welding technology provides high strength and avoids residual contamination during manufacture, which is often a problem with alternative welding procedures such as friction welding. This innovative concept ensures outstanding filter performance, which is needed to protect the sensitive parts inside modern transmissions. This is particularly applicable for the directly controlled valves inside the transmission control units, but also for other components such as clutch plates and pumps, which must be protected by relevant filtration.

The suction side filter module delivers high levels of filtration performance in eliminating the need for a separated pressure filter. Pressure filters require extra installation space and additional components such as a pressure filter housing or caps, connecting channels and adapters, and additional processes such as machining, assembly and logistical elements, in order to achieve cost savings.

Another example of a complex filter module designed by Filtran for highly efficient filtration on the suction side of the pump is the company’s plastic oil pan module, applied in the Mercedes-Benz 9G-tronic (Daimler NAG-3). In this case, the installation space available meant that an alternative solution was needed to integrate the fine filter media into the sump filter. Multiple flat layers, stapled in a progressive way for improved filter effectiveness, are placed in front of the medium-efficiency filter media, while the fine filter media layers incorporate partial flow openings (bypass orifices), which act as a self-regulating system. In cold conditions, where the automatic fluid is highly viscous, most of the flow will bypass the fine media layers, but in operating conditions where the viscosity of the oil is much lower, a certain amount of flow runs through the fine filter media layers as well, so a high level of cleanliness can be achieved over time.filtran-image-5

Filtran calls this extremely compact design of fine filtration inside a suction filter ‘SmartMedia’. This clever solution increases filter performance by combining the benefits of different media types in one compact housing. It also provides benefits in terms of air extraction, avoiding pump cavitation and therefore reducing noise.

In the development phase, Filtran analyzed more than 1,000 oil samples and hundreds of filters that had undergone durability transmission testing, to confirm that an additional costly pressure filter was not required.

The SmartMedia construction is only considered in the bigger, fully integrated, main suction filter in front of the mechanical pump, while the smaller secondary filter is mounted in front of the electrical pump, so that the position tolerances can be offset during assembly of the module to the transmission. Both filters are manufactured using clean laser-welding technology.

Today, oil pan modules act as function-carriers – here the pan includes a reusable twist-lock plug; devices for oil-level management; lightweight plastic bonded magnets for capturing of iron particles; integrated gasket; and outer fixing elements.

This plastic oil pan module demonstrates the industry trend toward modularization and system supply, where interfaces and single components are eliminated. This means that the amount of suppliers needed is reduced as well as the logistical effort and assembly processes, which assists with budgetary requirements.

 

 

Filtran continues to optimize this technology, through refinement of the design, materials and functionality of the final product. In comparison with the predecessor (7G-tronic), which adopted a metal oil pan with separated filter, the new plastic oil pan module, designed strictly in accordance with the injection molding process and plastic component design, is 1.3kg lighter in weight and has additional integrated functions.

In the future, a higher level of functional integration is achievable. Heat exchangers, sensors, valves and pumps could be adapted to transmission pans or side covers.

filtran-image-6

Since 2001, when Filtran brought the plastic oil pan module to market, it has produced almost 20 million units. In preparation for future demand, Filtran has added to its production capabilities in Germany, the USA, China, Japan, and Korea, and it has established a new plant in San Luis Potosí in Mexico.

Learn more  about Filtran products

This entry was posted in Filtran and tagged . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s