Abstract:
A liquid filter housing formed by an enclosure having a sidewall, a bottom and an open top. The bottom is formed from a support structure coupled to a flat plate. The cover may also be formed from a support structure coupled to a flat plate. A support member may be located between the bottom and a mounting surface. The enclosure has an inlet and an outlet communicating with an interior of the enclosure. The inlet and the outlet may be mounted to the bottom and a feed pipe used to direct the inlet flow proximate to an upper section of the enclosure. The cover may be adapted to close the open top, for example using eyebolts.

Description:
BACKGROUND OF INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention generally relates to liquid filter and or strainer housings. More specifically, the present invention relates to cost efficient high throughput and or low pressure drop housings used in liquid filtration systems.  
           [0003]    2. Description of Related Art  
           [0004]    Filters are used in a wide range of processes, for example, removing contaminants from liquids. In general, an increase in the filter material surface area increases the operation interval before the filter material becomes unacceptably fouled. Increasing the size of filter housings increases capacity for filter material and thereby enables high throughput at low pressure differentials.  
           [0005]    A typical liquid filter and or strainer housing utilizes a removable flat or domed cover, a cylindrical sidewall and a domed or flat bottom. The filter housing components are selected to meet specific process pressure requirements. Also, the filter housing is designed to handle vibrations that may be induced by hydraulic shocks occurring in the filter housing during process starts, stops and interruptions.  
           [0006]    Filter housings are typically supplied with legs that raise the filter housing to enable location of process connections on the bottom and or integration with other process equipment, for example, liquid pumps with net positive suction head requirements.  
           [0007]    In the prior filter housings the cover and bottom have typically had a flat plate or a domed configuration. If a flat plate is used, the material thickness is increased to add the strength necessary to withstand the expected process pressures. As the diameter of the filter housing is increased, using increasing flat plate thickness becomes increasingly expensive from both a raw material and manufacturing process perspective. Also, manipulating the increasing weight of a thick flat cover becomes a significant burden for the operator. Because of these limitations, filter or strainer housings with an outside diameter of 12 inches or more are typically designed with domed covers and bottoms.  
           [0008]    The curved surfaces of a domed cover or bottom allow use of material having a thickness similar to the sidewall thickness. However, manufacture of domed covers or bottoms requires specialized equipment/processes. Domed covers or bottoms also increase the cost/complexity of connections, for example inlets, outlets, process sensors and or drains because of additional or specialized machining steps needed to adapt the connections to curved surfaces of the domed cover and or bottom. As the housing diameter is increased, costs associated with domed covers and bottoms become a significant percentage of overall housing materials and manufacturing costs.  
           [0009]    Competition within the filter housing industry has focused attention upon minimization of materials and manufacturing costs.  
           [0010]    Therefore, it is an object of the present invention to provide a method and apparatus that overcomes deficiencies in the prior art. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0011]    BRIEF DESCRIPTION OF THE FIGURESThe accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the invention.  
         [0012]    [0012]FIG. 1 is a cut-away side view of a first embodiment of a filter/strainer housing with a multiple filter/strainer configuration according to the invention.  
         [0013]    [0013]FIG. 2 is a partial cut-away top view of the housing of FIG. 1.  
         [0014]    [0014]FIG. 3 is a section bottom view along line A-A of FIG. 1.  
         [0015]    [0015]FIG. 4 is a cut-away side view of a second embodiment of a filter/strainer housing with a multiple filter/strainer configuration according to the invention.  
         [0016]    [0016]FIG. 5 is a bottom view of the second embodiment.  
         [0017]    [0017]FIG. 6 is a cut-away side view of a third embodiment of a filter/strainer housing with a multiple filter/strainer configuration according to the invention.  
         [0018]    [0018]FIG. 7 is a bottom view of the third embodiment.  
         [0019]    [0019]FIG. 8A is a top view of a cover casting.  
         [0020]    [0020]FIG. 8B is a side section view of the cover casting in FIG. 8A.  
         [0021]    [0021]FIG. 9A is a top view of a collar casting.  
         [0022]    [0022]FIG. 9B is a side section view of the collar casting in FIG. 9A.  
         [0023]    [0023]FIG. 10A is a top view of a bottom casting.  
         [0024]    [0024]FIG. 10B is a side section view of the bottom casting in FIG. 10A.  
         [0025]    [0025]FIG. 11A is a partial cut-away side view of a fourth embodiment of a filter/strainer housing, bottom connections omitted for clarity.  
         [0026]    [0026]FIG. 11B is a partial cut-away side view of a fifth embodiment of a filter/strainer housing, bottom connections omitted for clarity.  
         [0027]    [0027]FIG. 12 is a cut-away side view of a sixth embodiment of a filter/strainer housing using a filter cartridge configuration according to the invention. 
     
    
     DETAILED DESCRIPTION  
       [0028]    The following description describes embodiments of the invention for use with a filter media that is only generically described. One skilled in the art will fully appreciate that the present invention may be practiced with a wide range of filter media, ranging, for example, from osmotic membranes to wide gap strainers.  
         [0029]    As shown in FIGS. 1-3, a first embodiment of a filter housing assembly  20  may be configured to have a plurality of filters and or filter basket(s)  10 . Use of multiple filters and or filter basket(s)  10  increases the available filter media surface area. The filters and or filter basket(s)  10  are enclosed within the filter housing assembly  20  by a cylindrical filter housing sidewall  30 , a cover  40  and a bottom  50 .  
         [0030]    The filter housing assembly  20  may be formed from a wide range of metals and metal alloys selected depending upon the intended process parameters and liquid to be filtered. Examples of specific materials include, for example, stainless-steel, aluminum, titanium and/or carbon steel.  
         [0031]    The cover  40  may be configured for easy access to the interior of the filter housing assembly  20  via, for example, a cover swing handle  65 , eyebolt assembly(s)  60  and a pivot assembly  70 . By unscrewing the eyebolts  60  the cover  40  may be swung aside via the pivot assembly  70  allowing full access to the filter housing assembly  20  interior for exchange and or cleaning of the filters and or filter baskets  10 . When the eyebolt assembly(s)  60  are secured, the cover  40  may be sealed to the filter housing assembly  20  using an o-ring or other gasket to enable operation of a sealed, pressurized process. Various process and or sensor connections may be added to the cover  40 , for example, a vent port  185 . A plurality of legs  75  may be added to raise the filter housing assembly  20  above desired process connections and or provide necessary net positive suction head for associated process pumps. The legs  75  may be cost efficiently formed from, for example, standard angled material with or without feet.  
         [0032]    Process fluid flows into the filter housing assembly  20  via an inlet  80 , through the filter media and filter basket(s)  10  that are supported, for example, by a basket support plate  90 . Filtered process fluid then exits the filter housing through outlet  100 . Drain port(s)  110  allow the filter housing assembly  20  to be drained without removing interconnecting process piping.  
         [0033]    As shown, for example, by FIGS. 4-7, the inlet  80  and outlet  100  configuration may be modified to suit the intended process requirements. For example, as shown by FIG. 4, the outlet  100  may be located in the bottom  50 , where a fully draining connection is made to the flat bottom  50  surface. A further advantage of the bottom  50  connection is a simplification of the machining requirements to mate the outlet  100  to a flat rather than curved surface. As shown in FIG. 6, both the inlet  80  and the outlet  100  may be bottom mounted if an inlet riser  120  is used to internally route the process flow to an input side of the filter media. In this embodiment, the inlet riser  120  routes the process flow through and above the basket support plate  90 .  
         [0034]    The present invention replaces the former thick flat plate and or domed cover and bottom configurations with cost efficient assemblies using cast, forged or machined components as shown in FIGS. 8A-10B.  
         [0035]    As shown in FIGS. 8A and 8B, the cover  40  has a reinforcing cover support web  42  coupled to an outer ring. One skilled in the art will appreciate that the reinforcing cover support web  42  is provided for explanatory purposes and that a plurality of different cover support web  42  configurations are possible, each selected according to the desired connections, dimensions and process parameters required for a specific filter housing assembly  20 . The selected filter housing closure may be integrated with the cover  40 . For example, to accommodate eyebolt assembly(s)  60 , eyebolt assembly top support structure(s)  140  are formed in the cover  40 . A flat cover plate  45 , dimensioned to fit into a cover shoulder  47 , is attached to the cover  40 , for example, by welding. The reinforcing cover support web  42  provides the cover  40  with enhanced strength characteristics, allowing the flat cover plate  45  to have the same thickness as the filter housing sidewall  30 . Because the cover  40  in combination with the flat cover plate  45  has much less material overall compared to the prior thick flat plate, total weight and materials costs are reduced. Also, any required machining and or welding operations, for example to attach the cover swing handle  65  and vent port  185  are simplified, because they can be performed upon the substantially reduced thickness of flat cover plate  45 . Compared to prior domed covers, a cost advantage for the cover  40  increases with increasing filter housing assembly  20  diameter.  
         [0036]    The cover  40  seals against a collar  150 , as shown in FIGS. 9A and 9B. The collar  150  is connected, for example by welding, to the top edge of the filter housing sidewall  30 . Also, the collar  150  may include a plurality of eyebolt assembly bottom support structure(s)  145  arranged to correspond to the locations of the eyebolt assembly top support structure(s)  140  of the cover  40 . Because the eye bolt assembly top structure  140  and eyebolt assembly bottom structure  145  may be formed integrally with the cover  40  and the collar  150 , respectively, separate, for example, welding operations to connect each of them independently are eliminated.  
         [0037]    The bottom  50 , as shown in FIGS. 10A and 10B has a bottom support web  52  similar in design and function to the cover support web  42 . Also similar to the cover shoulder  47 , a bottom shoulder  57  is arranged to receive a flat bottom plate  55  that is, for example, welded to the bottom  50 .  
         [0038]    In addition to withstanding the operating pressure, the bottom  50  also carries the weight of any process fluids within the filter housing assembly  20 . The bottom  50  is strengthened by a support leg  170  located proximate the center of the cover. The support leg  170  may be formed from one or more pieces of angled, square or tubular material. As the diameter of the filter housing assembly  20  increases, multiple support leg(s)  170  may be used. Similar to the legs  75 , feet may also be attached to the support leg(s)  170 .  
         [0039]    The support leg  170  significantly increases the strength of the filter housing assembly  20 . In alternative embodiments, the support leg  170  allows the replacement of the bottom  50  with simplified structure. As shown in FIG. 11A, depending upon the dimensions and process requirements of the filter housing assembly  20 , the bottom  50  may be replaced with a flat bottom support ring  195 , formed for example from angle material bent into a circle and welded to itself. If pressure requirements are low, a flat bottom plate  55 , with a support leg  170 , may be welded to the filter housing sidewall  30  without further reinforcement, as shown in FIG. 11B.  
         [0040]    The flat bottom support ring  195  may also be used, for example, to support an internal support plate  199 , which may also be reinforced by one or more interior support legs  197 . As shown in FIG. 12, this configuration may be used, for example, where the filter is a filter cartridge  201  mounted onto a perforated center support  198  by a retaining nut  200  that secures the filter cartridge  201  between the internal support plate  199  and a cartridge retaining member  190 . Process flow entering the inlet  80  is forced through the filter cartridge  201  to the perforated center support  198  which is coupled, through the internal support plate  199 , to the outlet  100 . Alternatively, multiple filter cartridge(s) may be located either stacked upon each other or each upon a separate perforated center support  198 .  
         [0041]    To manufacture a filter housing assembly  20  according to the present invention, appropriate cover  40 , collar  150  and bottom  50  are fabricated, for example, by casting. These castings may be economically outsourced to third parties specializing in metal casting production. However, one skilled in the art will appreciate that the invention is not limited to castings. Other methods of forming the cover  40 , collar  150  and bottom  50 , for example welding, machining and or cutting may be used. Appropriately dimensioned pieces of material having any necessary openings for process connections are then, for example, welded to the cover  40 , and bottom  50 . The filter housing sidewall  30  may be fabricated by rolling a single sheet of material into a cylindrical form that is then welded to itself to form a tube having the desired filter housing assembly  20  diameter. The tube then has the collar  150 , for example, welded to a top end and the bottom  50 , flat bottom support ring  195 , and or flat bottom plate  55  is, for example, welded to a bottom end. Desired legs  75 , bottom support leg(s)  170 , support plate  90 , process connections and/or feed pipe  120  may also be added by, for example, welding. The remainder of the filter housing assembly  20 , for example, filters and/or filter baskets  10 , pivot assembly  70  and eyebolts  60  may be hand assembled.  
         [0042]    One skilled in the art will appreciate that the present invention enables manufacture of pressurizable filter housings  20  with a reduction of required manufacturing operations and or components/raw materials costs. Also, the present invention provides a means for creating large diameter filter housings  20  without use of expensive domed tops and or bottoms or difficult to machine and manipulate thick plate material.  
                                         Table of Parts                                 10   filter basket        20   filter housing assembly        30   filter housing sidewall        40   cover        42   cover support web        45   flat cover plate        50   bottom        52   bottom support web        55   flat bottom plate        60   eyebolt assembly        65   cover swing handle        70   pivot assembly        75   legs        80   inlet        90   basket support plate       100   outlet       110   drain port       120   inlet riser       140   eye bolt assembly top support structure       145   eye bolt assembly bottom support structure       150   collar       170   flat bottom support leg       185   vent port       190   cartridge retaining member       195   flat bottom support ring       197   internal support leg       199   interior baffle       200   retaining nut       201   filter cartridge                  
 
         [0043]    Where in the foregoing description reference has been made to ratios, integers, materials, components or modules having known equivalents then such equivalents are herein incorporated as if individually set forth.  
         [0044]    While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus, methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of applicant&#39;s general inventive concept. Further, it is to be appreciated that improvements and/or modifications may be made thereto without departing from the scope or spirit of the present invention as defined by the following claims.