MULTILAYER COMPOSITE WASTE TUBE

Abstract

According to the present invention, a waste tube with component layers is provided. An inner layer resisting at least one waste material system chemical and an outer composite wrapping layer each runs along the length of the waste tube. The impact zones of the waste tubes, defined by bends, tapers or junctions incorporated in the tube, are reinforced by an elastomeric barrier layer over an outer face of the inner layer and an impact absorption layer over the elastomeric barrier layer, wrapped by the outer composite layer. In another aspect, a method of manufacturing the waste tube is provided where a preformed tubular liner for building the component layers functions as the inner layer in the waste tube.

Claims

1. A waste tube defining a passage therethrough for carrying waste material and potential projectiles in a pressurized system, said waste tube having a series of component layers, comprising: an inner layer resistant to at least one waste system chemical defining an interior tubular surface of said waste tube for resisting bio-film build-up of material traveling within said passage of said waste tube; an outer composite wrapping layer defining an exterior tubular surface of said waste tube for wrapping said component layers; an elastomeric barrier layer optionally therebetween on at least one impact zone defined by bends, tapers or junctions of said tube for providing shock absorption and distribution, and leakage barrier against material and projectiles traveling within said passage of said tube; and an impact absorption layer between said elastomeric barrier layer and said outer composite wrapping layer for the impact absorption of projectiles on said at least one impact zone.

2. The waste tube of claim 1, wherein said inner layer is a thermoplastic liner.

3. The waste tube of claim 2, wherein said thermoplastic liner is selected from the group consisting of: fluoropolymers that are thermoformable, High and Medium Density Polyethylene (HDPE, MDPE), Cross-link Polyethylene (XLPE or PEX) and perfluoroalkoxy (PFA)

4. The waste tube of claim 1, wherein said inner layer is a thermoset plastic liner.

5. The waste tube of claim 1, wherein said outer composite wrapping layer is selected from a group consisting of: carbon fiber, fiberglass, and Aramid fiber.

6. The waste tube of claim 1, wherein said elastomeric barrier layer is a rubberer.

7. The waste tube of claim 6 wherein said elastomeric barrier layer is selected from silicone rubber and Viton rubber.

8. The waste tube of claim 1, wherein said impact absorption layer is a metal patch.

9. The waste tube of claim 8, wherein said metal patch comprises titanium.

10. The waste tube of claim 8, wherein said metal patch comprises stainless steel.

11. The waste tube of claim 8, wherein said metal patch is approximately 0.001-0.100 inches in thickness.

12. A method of manufacturing the waste tube of claim 1 comprising: providing a preformed tubular liner defining a passage therethrough, said preformed tubular liner comprising a material resistant to at least one waste material system chemical wherein said preformed tubular liner functions as said inner layer for said waste tube; adding said elastomeric barrier layer over an outer face of said pre-formed tubular liner on at least one impact zone defined by bends, tapers or junctions of said preformed tubular liner; placing said impact absorption layer over said elastomeric barrier layer; and wrapping said layers with said outer composite wrapping layer for providing an exterior surface of said waste tube.

13. A tube defining a passage therethrough for carrying at least one fluid and potential projectiles in a pressurized system, said tube having a series of component layers, comprising: an inner layer resistant to said at least one fluid defining an interior tubular surface of said waste tube; an outer composite wrapping layer defining an exterior tubular surface of said tube for wrapping said component layers; an elastomeric barrier layer optionally therebetween on at least one impact zone defined by bends, tapers or junctions of said tube for providing shock absorption and distribution, and a leakage barrier against fluid and projectiles traveling within said passage of said tube; and an impact absorption layer between said elastomeric barrier layer and said outer composite wrapping layer for the impact absorption of projectiles on said at least one impact zone.

14. (canceled)

15. The waste tube of claim 1, wherein said inner layer is selected from the group consisting of a polyamide, acrylonitrile butadiene styrene (ABS), Polyvinylidene Difluoride (PVDF), PVC, CPVC, EFEP and combinations thereof.

16. The waste tube of claim 1, wherein said inner layer is a thermoset plastic liner selected from PEEK and PEI.

17. The waste tube of claim 1 wherein said inner layer is selected from polytetrafluoroethylene (PTFE) and fluorinated ethylene propylene (FEP).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings wherein:

[0011] FIG. 1 is a perspective partially cut away view of an exemplary tube having a bend;

[0012] FIG. 1A is an enlargement of the encircled portion A of FIG. 1;

[0013] FIG. 1B is an enlargement of the encircled portion B of FIG. 1;

[0014] FIG. 2 is a perspective partially cut away view of an exemplary tube having a junction;

[0015] FIG. 2A is an enlargement of the encircled portion A of FIG. 2;

[0016] FIG. 3A is a partially cut away view of an exemplary tube end with the inner layer in a closed configuration;

[0017] FIG. 3B is a partially cut away view of an exemplary tube end with the inner layer in a flush configuration; and

[0018] FIG. 3C is a partially cut away view of an exemplary tube with the inner layer in a bent configuration.

[0019] FIG. 3D is a partially cut away view of an exemplary tube with the inner layer in an encapsulated configuration.

DETAILED DESCRIPTION

[0020] One or more currently preferred embodiments have been described by way of example.

[0021] One aspect of the present invention provides a waste tube, indicated generally by the reference numeral 100 in the accompanying figures, defining a passage 106 therethrough for carrying waste material and projectiles in a pressurized system. The waste tube 100 may be straight or incorporate bends, angles, tapers or junctions such as manifolds, pullouts, tees and wyes. The waste tube 100 may also be any suitable circumference as well as any suitable cross-section to carry waste substances. Examples are symmetrical shapes such as circular, edged and elliptic forms, or asymmetric shapes.

[0022] In the illustrated embodiments, the exemplary waste tube 100 is shown as a cylindrical tube. FIG. 1 illustrates a waste tube 100 incorporating a bend and having a generally circular cross-section. FIG. 2 illustrates a waste tube 100 incorporating a junction or pullout along with a generally circular cross-section. The regions incorporating the bend and the junction are illustrated as impact zones 120.

[0023] The waste tube 100 is comprised of a series of component layers. The innermost layer of the tube is an inner layer 150 resistant to at least one waste system chemical. Defining the interior tubular surface 102 of the waste tube 100, the inner layer 150 limits the build-up of bio-film either inherently or through the use of additives and generally resists the chemical activity of material traveling within the waste tube 100 that can otherwise damage or cause leakage through the waste tube 100. This inner layer 150 may be a thermoplastic layer that resists various industrial chemicals and solvents as well provides resistance to bio-film build-up. This chemical and bio-film resistant property of the inner layer 150 permits the waste tube 100 to carry waste materials within its passage 106 while limiting the build-up of bio-film resulting from such waste substances. It also resists breach by various other chemical compositions that travel through the waste tube 100. Examples of thermoplastics that may be used to line the interior of the waste tube 100 include fluoropolymers that are thermoformable such as polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), High and Medium Density Polyethylene (HDPE, MDPE), Cross-link Polyethylene (XLPE or PEX), and perfluoroalkoxy (PFA) among others. The inner layer 150 may additionally be polyamide (nylon), acrylonitrile butadiene styrene (ABS), Polyvinylidene Difluoride (PVDF) or combinations thereof. Such combinations could be co-extruded or otherwise formed. Other examples include: PVC, CPVC, EFEP, etc. The inner layer 150 may also be a thermoset plastic layer, such as PEEK, PEI, etc.

[0024] The outermost layer of the waste tube 100 is an outer composite wrapping layer 152 defining the exterior tubular surface 104 of the waste tube 100. This outer composite wrapping layer 152 wraps the remaining component layers. The composite wrapping layer 152 could be, for example, a carbon fiber epoxy, fiberglass, or Aramid fiber among others, such as Dyneema, S-Glass, S2-Glass, Spectra, or any other suitable material known to one skilled in the art,. This outer composite layer 152 functions as a sleeve to wrap the remaining component layers of the tube 100. This layer, such as carbon fiber epoxy can impart mechanical strength and withstand temperature fluctuations among other desirable properties. It also functions as a secondary leakage barrier. Other composites known to one skilled in the art may also be used for the outer composite wrapping layer 152.

[0025] While the inner layer 150 and the outer composite wrapping layer 152 run along the entire length of the waste tube 100, the impact zones 120 are reinforced with additional layers. Thus, the inner layer 150 and outer composite layer 152 register with each other along much of the waste tube 100 but are separated along the impact zones 120 by reinforcing layers.

[0026] An elastomeric barrier layer 154 optionally rests between the inner layer 150 and the outer composite wrapping layer 152 at the impact zones 120. The elastomeric barrier layer 154 provides impact damping, distribution and absorption functionalities and represents an additional leakage barrier against waste material and projectiles that may travel within the passage 106 of the waste tube 100. In particular, as an unintended projectile, such as a battery, impacts the impact zone 120, the elastomeric barrier layer 154 damps, distributes and absorbs the stresses, and provides a barrier against leakage. The elastomeric barrier layer 154 may be Viton rubber or silicone rubber or any other suitable elastomeric material known to one skilled in the art, and be variable in wall thickness depending on the application requirements.

[0027] An impact absorption layer 156 rests between the elastomeric barrier layer 154 and the outer composite wrapping layer 152 to reinforce the impact zone 120. The impact absorption layer 156 may be a metal patch such as stainless steel or titanium. The impact absorption layer 156 mainly absorbs the impact of any unintended projectiles, such as batteries or cell phones, along the radii of the bend or curve defining the impact zone 120 or along the linear portion of the tube 100 where a junction is incorporated. By absorbing the impact, the impact absorption layer 156 resists breach of the waste tube 100 at the impact zone 120. The metal patch may be of any suitable thickness that prevents breach of the waste tube 100, for example, between 0.001 and 0.100 inches.

[0028] The surface area occupied by the elastomeric barrier layer 154 may be the same (not shown) or greater than the surface area occupied by the impact absorption layer 156 (FIG. 1B). This coverage provided by the elastomeric barrier layer 154 to the impact absorption layer 156 limits the impact absorption layer's 156 contact with corrosive chemicals and waste materials that flow through any breach of the inner layer 150 resulting from the impact of a projectile at the impact zone 120. For example, Viton rubber forming the elastomeric barrier layer 154 provides shock absorption and a leakage barrier against the potentially corrosive activity of chemicals carried in the waste stream that may otherwise reach the impact absorption layer 156 (e.g., titanium metal patch).

[0029] The reinforcement of impact zones 120 with an impact absorption layer 156 and an elastomeric barrier layer 154 advantageously limits the weight of such a waste tube 100. It may also reduce the overall cost of the waste tube 100.

[0030] Another aspect of the present invention provides a method of manufacturing such a waste tube as described above.

[0031] First, a preformed tubular liner defining a passage 106 is provided. The preformed tubular liner comprises a material resistant to at least one waste material system chemical, and the preformed tubular liner functions as an inner layer 150 for the waste tube 100 as well as a support layer for other layers described below. In this way, the preformed tubular liner need not be later dissolved or extracted but remains as an inner layer 150 of the waste tube 100.

[0032] An elastomeric barrier layer 154 is added over an outer face (not shown) of the preformed tubular liner and distal the passage 106. The elastomeric barrier layer 154 is added on at least one impact zone 120 defined by bends, tapers or junctions of the preformed tubular liner as described above. An impact absorption layer 156 is also added over the elastomeric barrier layer 154. An outer composite wrapping layer 152 is added for providing an exterior surface 104 of the waste tube 100. The inner layer 150 may be over molded with the outer composite wrapping layer 152 or it may be co-molded with the outer composite wrapping layer 152 and later bonded at the ferrules 160 placed at the tube ends. The use of ferrules 160 provides articulable connecting joints between adjacent waste tubes.

[0033] The inner layer 150 may be sealed at the ferrules 160, or at tube ends, in multiple ways. For example, as shown in FIG. 3A, the inner layer 150 may be in a closed configuration where the ferrule 160 extends over the inner layer 150. Alternatively, the inner layer 150 and ferrule 160 may be in flush configuration as shown in FIG. 3B. In still another alternative, the inner layer 150 may be folded to extend over the outer composite layer 152 as well as the ferrule 160 to create a bend configuration as in FIG. 3C. In another alternative, the inner layer 150 and composite wrapping layer 152 may be encapsulated by the ferrule as shown in FIG. 3D.

[0034] Although the above description relates to tubes for waste systems, it will be appreciated that such tubes may be used in other fluid carrying applications. Accordingly, the description should not be considered as limited to waste tube applications but should also be considered as applicable to conveying air and other materials.

[0035] The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.

PARTS LIST

[0036] 100 waste tube [0037] 102 interior tubular surface [0038] 104 exterior tubular surface [0039] 106 passage [0040] 120 impact zone [0041] 150 inner layer [0042] 152 outer composite layer [0043] 154 elastomeric barrier layer [0044] 156 impact absorption layer [0045] 160 ferrule