Filter media suitable for hydraulic applications

Patent metadata

Field	Value
Publication number	US-10022657-B2
Application number	US-201414584064-A
Country	US
Kind code	B2
Filing date	Dec 29, 2014
Priority date	Apr 3, 2009
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

Filter media, including those suitable for hydraulic applications, and related components, systems, and methods associated therewith are provided. The filter media described herein may include two or more layers, at least one of the layers having a relatively high percentage of microglass fibers. Additionally, the filter media may be designed such that the ratio of average fiber diameters between two layers is relatively small, which can lead to a relatively low resistance ratio between the layers. The filter media has desirable properties including high dirt holding capacity with low basis weight and a low resistance to fluid flow. The media may be incorporated into a variety of filter element products including hydraulic filters.

First claim

What is claimed is:

1. A filter media comprising:
a first layer comprising fibers, wherein the fibers in the first layer comprise glass fibers, and wherein the fibers in the first layer have a first average diameter; and
a second layer adjacent the first layer comprising fibers, wherein the fibers in the second layer comprise glass fibers, and wherein the fibers in the second layer have a second average diameter,
wherein each of the first and second layers has a thickness between about 3 mils and 100 mils,
wherein the first and second layers have a combined basis weight of less than 200 g/m 2 as measured by TAPPI Standard T410 and an absolute specific capacity at 10 microns of greater than about 2.5,
wherein the filter media has a thickness of between about 5 mils and about 300 mils,
wherein the absolute specific capacity at 10 microns is a product of a dirt holding capacity of the filter media as measured by a Multipass Filter Test and a square root of a log of a Beta(x) value for 10 micron and larger particles as measured by the Multipass Filter Test divided by an overall basis weight of the filter media as measured by TAPPI Standard T410, and
wherein the Multipass Filter Test is a measurement performed in accordance with a procedure described in ISO 16889 using a hydraulic test fluid, a dust level of 10 mg/liter, and a face velocity of 0.14 meters/min, and performed until a terminal pressure of 172 kPa above a baseline filter pressure drop is obtained.

2. The filter media of claim 1 , wherein the absolute specific capacity at 10 microns of the filter media is greater than about 2.75.

3. The filter media of claim 1 , wherein a normalized resistance ratio of the second layer to the first layer is between 1:1 and 5:1, and wherein the normalized resistance ratio is a ratio of a resistance of the second layer as measured by TAPPI Method T251 divided by a basis weight of the second layer as measured by TAPPI Standard T410 to a resistance of the first layer as measured by TAPPI Method T251 divided by a basis weight of the first layer as measured by TAPPI Standard T410.

4. The filter media of claim 1 , wherein at least one of the first and second layers comprises at least 70 wt % glass fibers.

5. The filter media of claim 1 , wherein at least one of the first and second layers comprises at least 80 wt % glass fibers.

6. The filter media of claim 1 , wherein each of the first and second layers comprises at least 80 wt % glass fibers.

7. The filter media of claim 6 , wherein the first and second layers are directly adjacent to one another.

8. The filter media of claim 7 , wherein the first layer has coarser fibers than the second layer.

9. The filter media of claim 8 , wherein the second average diameter is less than 3 μm.

10. The filter media of claim 8 , wherein the first layer has a basis weight of between 20 g/m 2 and 50 g/m 2 as measured by TAPPI Standard T410.

11. The filter media of claim 10 , wherein the second layer has a basis weight of between 20 g/m 2 and 50 g/m 2 as measured by TAPPI Standard T410.

12. The filter media of claim 8 , wherein the first layer includes synthetic fibers, and wherein the synthetic fibers are present in an amount of less than or equal to about 15 wt % of the first layer.

13. The filter media of claim 1 , wherein at least one of the first and second average diameters is between 0.5 and 5.5 microns.

14. The filter media of claim 1 , wherein at least one of the first and second layers includes microglass fibers having an average diameter of between 1 μm and 6 μm.

15. The filter media of claim 1 , wherein at least one of the first and second layers has a basis weight of less than 40 g/m 2 as measured by TAPPI Standard T410.

16. The filter media of claim 1 , wherein the overall basis weight of the filter media is about 100 g/m 2 or less as measured by TAPPI Standard T410.

17. The filter media of claim 1 , wherein the thickness of at least one of the first and second layers is between about 3 mils and 40 mils.

18. The filter media of claim 1 , wherein the first and second layers are directly adjacent to one another, wherein each of the first and second layers comprises at least 80 wt % glass fibers, wherein the first layer has coarser fibers than the second layer, wherein at least one of the first and second average diameters is between 0.5 and 5.5 microns, wherein the first layer has a basis weight between 20 g/m 2 and 50 g/m 2 as measured by TAPPI Standard T410, and wherein the second layer has a basis weight between 20 g/m 2 and 50 g/m 2 as measured by TAPPI Standard T410.

19. The filter media of claim 18 , wherein a normalized resistance ratio of the second layer to the first layer is between 1:1 and 10:1, and wherein the normalized resistance ratio is a ratio of a resistance of the second layer as measured by TAPPI Method T251, divided by the basis weight of the second layer as measured by TAPPI Standard T410, to a resistance of the first layer as measured by TAPPI Method T251, divided by the basis weight of the first layer as measured by TAPPI Standard T410.

20. The filter media of claim 18 , wherein each of the first and second layers comprises at least 90 wt % glass fibers, wherein the first average diameter is between 0.5 and 5.5 microns, and wherein the second average diameter is less than 3 μm.

21. The filter media of claim 20 , wherein the absolute specific capacity at 10 microns of the filter media is greater than about 3.4.

22. The filter media of claim 18 , wherein the first average diameter is between 0.5 and 5.5 microns, and wherein the second average diameter is less than 3 μm.

23. The filter media of claim 22 , wherein the first layer includes synthetic fibers, and wherein the synthetic fibers are present in an amount of less than or equal to about 15 wt % of the first layer.

24. The filter media of claim 18 , wherein the absolute specific capacity at 10 microns of the filter media is greater than about 2.75.

25. A hydraulic filter element comprising the filter media of claim 1 , wherein the hydraulic filter element further comprises a housing.

26. The filter media of claim 1 , wherein each of the first and second layers comprises at least 90 wt % glass fibers.

27. A filter media comprising:
a first layer comprising fibers, wherein the fibers in the first layer comprise glass fibers, and wherein the fibers in the first layer have a first average diameter;
a second layer adjacent the first layer comprising fibers, wherein the fibers in the second layer comprise glass fibers, and wherein the fibers in the second layer have a second average diameter; and
a third layer adjacent one of the first or second layers comprising fibers, wherein the fibers in the third layer have a third average diameter,
wherein each of the first and second layers has a thickness between about 3 mils and 100 mils,
wherein the first and second layers have a combined basis weight of less than 200 g/m 2 as measured by TAPPI Standard T410,
wherein the filter media has a thickness of between about 5 mils and about 300 mils,
wherein the filter media has an absolute specific capacity at 10 microns of greater than about 2.0,
wherein the absolute specific capacity at 10 microns is a product of a dirt holding capacity of the filter media as measured by a Multipass Filter Test and a square root of a log of a Beta(x) value for 10 micron and larger partic

Assignees

• Hollingsworth & Vose Co

Inventors

• Godsay Milind
• Keisler Randall

Classifications

• B01D2239/1233

  Fibre diameter · CPC title

• Y10T428/249969

  Of silicon-containing material [e.g., glass, etc.] · CPC title

• B01D2239/0654

  Support layers · CPC title

• B01D39/163

  sintered or bonded · CPC title

• Y10T428/249964

  Fibers of defined composition · CPC title