Fluid circuit with integrated electrostatic discharge mitigation

Abstract

To improve electrostatic discharge (ESD) mitigation in an ultra-pure fluid handling system.SOLUTION: A fluid circuit includes a plurality of tubing segments and a plurality of operative components. Each of the tubing segments includes i) a non-conductive polymer portion defining a fluid passageway and ii) one or more interior conductive fluoropolymer stripes extending axially to the ends of the tubing segment. Each of the operative components includes a conductive fluoropolymer that extends between a plurality of tubing connector fittings forming a part of the fluid circuit. Each of the tubing connector fittings conductively connects each conductor of the operative component to the interior conductive fluoropolymer stripes of the tubing segment to provide a path to ground that extends through each operative component and each tubing segment.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure are directed to fluid processing systems, and more particularly, to ultra-high purity fluid processing systems with electrostatic discharge mitigation. [Background technology]

[0002] Fluid handling systems that provide high purity standards have many uses in advanced technology applications. These applications include the processing and manufacturing of solar panels, flat panel displays, and in the semiconductor industry, applications such as photolithography, bulk chemical delivery, chemical mechanical polishing (CMP), wet etching, and cleaning. Certain chemicals used in these applications are particularly corrosive, preventing the use of conventional fluid handling techniques due to the potential for corrosion of fluid handling components and leaching of chemicals into the environment.

[0003] To meet the corrosion resistance and purity requirements of such applications, fluid handling systems provide tubing, fittings, valves, and other components made from inert polymers. These inert polymers can include, but are not limited to, fluoropolymers such as tetrafluoroethylene polymer (PTFE), perfluoroalkoxyalkane polymer (PFA), ethylene and tetrafluoroethylene polymer (ETFE), ethylene, tetrafluoroethylene, and hexafluoropropylene polymer (EFEP), and fluorinated ethylene propylene polymer (FEP). In addition to providing a noncorrosive and inert structure, many fluoropolymers, such as PFA, can be injection molded and extruded. Several types of connector fittings made from such polymers are available and known, such as PRIMELOCK® fittings, PILLAR® fittings, flare fittings, and other fittings. Exemplary fittings are described, for example, in U.S. Patent Nos. 5,629,999; 5,629,999; 5,629,999; 5,629,999; and 5,629,999. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 5,154,453 [Patent Document 2] U.S. Patent No. 6,409,222 [Patent Document 3] U.S. Patent No. 6,412,832 [Patent Document 4] U.S. Patent No. 6,601,879 [Patent Document 5] U.S. Patent No. 6,758,104 [Patent Document 6] U.S. Patent No. 6,776,440 [Non-patent literature]

[0005] [Non-Patent Document 1] NFPA 77, "Recommended Practice on Static Electricity," pp. 77-1 to 77-67, 2014 Summary of the Invention [Problem to be solved by the invention]

[0006] Electrostatic discharge (ESD) is a significant technical issue for fluid handling systems in the semiconductor industry and other technology applications. Frictional contact between fluids and the surfaces of various working components in fluid systems (tubing, piping, valves, fittings, filters, etc.) can result in the generation and accumulation of electrostatic charges. The extent of charge generation depends on a variety of factors, including, but not limited to, component and fluid properties, fluid velocity, fluid viscosity, fluid conductivity, path to ground, turbulence and shear in the liquid, the presence of air in the fluid, and surface area. These characteristics, and methods for mitigating unwanted electrostatic charges caused by these characteristics, are described and reported in "Electrostatic Discharge and ESD: A Practical Guide to Fluid Processing," by John Wiley & Sons, Inc., 1999.

[0007] Additionally, as fluids flow through a system, charge can be carried downstream in a phenomenon called streaming charge, which can build up beyond the point where the charge originated. Sufficient charge buildup can cause ESD on tubing and pipe walls, on component surfaces, and even on substrates and wafers during various processing steps.

[0008] In some applications, semiconductor substrates or wafers are highly sensitive to electrostatic charges, and such ESD can damage or destroy the substrate or wafer. For example, uncontrolled ESD can disrupt circuitry on the substrate and activate photoactive compounds before normal exposure. Furthermore, accumulated electrostatic charges can be released from within the fluid handling system to the external environment, damaging fluid handling system components (e.g., tubing or piping, fittings, components, containers, filters, etc.), potentially leading to leaks, spillage of fluids within the system, and reduced component performance. In these situations, such discharges can lead to potential fires or explosions when flammable, toxic, and / or corrosive fluids are used in compromised fluid handling systems.

[0009] In some fluid treatment systems, to reduce the buildup of static charge, certain metal or conductive components within the fluid treatment system are grounded to mitigate the buildup of static charge within the system, and the charge is continuously dissipated from the metal or conductive components to ground. Conventional use of multiple grounding straps can introduce excessive mechanical disruption into the fluid treatment system, can lead to complex grounding system networks that require extensive maintenance, or can lead to complex systems that may result in undesirable failures.

[0010] It would be desirable to improve ESD mitigation in ultra-high purity fluid processing systems to improve component performance and reduce potentially damaging ESD events. [Means for solving the problem]

[0011] One or more embodiments of the present disclosure relate to a fluid circuit in a fluid processing system with ESD mitigation. In one or more embodiments, the fluid circuit includes a plurality of conductive operative components and tubing segments.

[0012] In certain embodiments, a fluid circuit for a predetermined fluid flow path (e.g., gas or liquid, or both) having at least one inlet and at least one outlet includes a plurality of tubing segments and a plurality of working components. Each working component includes a body portion with an internal fluid flow path and a plurality of tubing connector fittings. The working component connects the plurality of tubing segments at selected tubing connector fittings, and the plurality of tubing segments and working components provide a fluid flow path through the fluid circuit. Each tubing segment includes (i) a non-conductive polymer portion defining a fluid passageway and (ii) one or more internal conductive fluoropolymer stripes extending axially to an end of the respective tubing segment. The body portion of each working component includes a conductive fluoropolymer extending between each of the plurality of tubing connector fittings, and each tubing connector fitting conductively connects a respective conductor of the body portion to the internal conductive fluoropolymer stripe of the tubing segment.

[0013] Another disclosed embodiment is a method for creating an electrostatic discharge mitigation fluid circuit for a predetermined fluid flow path having at least one inlet and at least one outlet, the method including conductively connecting a plurality of pipe segments to a plurality of working components. Each working component includes a body portion having an internal fluid flow path and a plurality of pipe connector fittings. The working component connects the plurality of pipe segments at selected pipe connector fittings, and the plurality of pipe segments and working components provide a fluid flow path through the fluid circuit. Each pipe segment includes (i) a non-conductive polymer portion defining a fluid passageway and (ii) one or more internal conductive stripes of conductive fluoropolymer. The conductive fluoropolymer is bonded to and uniformed within the non-conductive polymer portion extending axially to the end of each pipe connector fitting. Each body portion includes a conductive fluoropolymer extending between each of the plurality of pipe connector fittings. Each pipe connector fitting conductively connects a respective conductor of the body portion to at least one of the internal conductive fluoropolymer stripes of the pipe segment to ground the electrostatic discharge mitigation fluid circuit.

[0014] In various embodiments, to provide conductive paths and fluid passages through the fluid circuit, the actuating components are connected by one or more tubing segments that connect to the components at their respective tubing connector fittings. Suitable actuating components include, for example, valves, straight connectors, T-connectors, elbow connectors, multi-connector manifolds, filters, heat exchangers, or sensors. Suitable sensors may include, for example, flow controllers, regulators, flow meters, pressure gauges, or variable area meters. In one or more embodiments, the body portion of the actuating component may be coupled to a conductive portion extending between the connector fitting and the fluid flow path, and may be uniform.

[0015] In certain embodiments, each of the plurality of pipe segments includes a non-conductive polymer portion and one or more internal conductive fluoropolymer stripes extending axially with the non-conductive polymer pipe portion, the conductive fluoropolymer stripes of the pipe segment conductively connecting to the conductive pathways of the body portion at the pipe connector joint.

[0016] In one or more embodiments, each tubing connector fitting conductively connects a conductive pathway in the body portion to a stripe of conductive fluoropolymer in the tubing portion connected to the respective tubing connector fitting.

[0017] The above summary is not intended to describe each illustrated embodiment or every implementation of the present disclosure. The drawings included in this disclosure illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure. The drawings are only illustrative of particular embodiments and are not intended to limit the disclosure. [Brief explanation of the drawings]

[0018] [Figure 1] 1 illustrates a fluid processing system and fluid circuit according to one or more embodiments of the present disclosure. [Figure 2] 1 illustrates actuation components and connected tubing segments according to one or more embodiments of the present disclosure. [Figure 3] 1 illustrates an actuation component, a pipe connector fitting, a fitting nut, and a pipe segment according to one or more embodiments of the present disclosure. [Figure 4a] 4a and 4b show a side view of an actuation component having a tubing connector fitting (FIG. 4a) and a tubing segment (FIG. 4b) according to one or more embodiments of the present disclosure. [Figure 4b] 4a and 4b show partial cross-sectional views of an actuation component having a tubing connector fitting (FIG. 4a) and a tubing segment (FIG. 4b) according to one or more embodiments of the present disclosure. [Figure 5a] 1 illustrates a cross-sectional view of an actuation component according to one or more embodiments of the present disclosure. [Figure 5b] It shows a cross-sectional view seen along the cutting line 5-1 of FIG. 5a. [Figure 5c] It shows a cross-sectional view of an alternative embodiment seen along the cutting line 5-1 of FIG. 5a. [Figure 5d] It shows a cross-sectional view of an alternative embodiment seen along the cutting line 5-1 of FIG. 5a. [Figure 5e] It shows a cross-sectional view of an alternative embodiment seen along the cutting line 5-1 of FIG. 5a. [Figure 6a] It shows an exploded isometric view of a filter having two end caps according to one or more embodiments of the present disclosure. [Figure 6b] It shows an isometric view of a filter having two end caps according to one or more embodiments of the present disclosure. [Figure 7a] It shows an exploded isometric view of a filter having one end cap according to one or more embodiments of the present disclosure. [Figure 7b] It shows an isometric view of one end cap according to one or more embodiments of the present disclosure. [Figure 8a] It shows an isometric view of an alternative embodiment of the pipe segment of the present disclosure. [Figure 8b] It shows an isometric view of an alternative embodiment of the pipe segment of the present disclosure. [Figure 8c] It shows an isometric view of an alternative embodiment of the pipe segment of the present disclosure. [Figure 8d] It shows an isometric view of an alternative embodiment of the pipe segment of the present disclosure. [Figure 9] It shows a digital image of the pipe segment of the present disclosure. [Figure 10] It shows the extrusion system of the present disclosure. [Figure 11] It shows a Faraday cup device used to test the ability of different pipe segments to generate static charges.

MODE FOR CARRYING OUT THE INVENTION

[0019] The embodiments of the present disclosure are amenable to various modifications and alternative forms, and specific details have been shown, for example, in the drawings and described in detail. It is understood that it is not intended to limit the disclosure to the particular embodiments described. The intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure.

[0020] This disclosure reports embodiments of fluid processing systems with ESD mitigation, including a fluid flow path from a fluid supply to one or more downstream processing stages. This system embodiment includes a fluid circuit including conductively connected working components and tubing segments. Some prior ESD mitigation fluid circuits are reported, for example, in International Patent Application WO 2017 / 210293, which is incorporated herein by reference except where expressly defined or claimed. Other ESD mitigation fluid circuits are reported, for example, in Entegris' brochure, Fluoroline Electrostatic (ESD) Tubing, 2015-2017.

[0021] In this disclosure, a working component refers to any component or device that has a fluid input and a fluid output and connects to a pipe to direct or provide fluid flow. Examples of working components include, but are not limited to, fittings, valves, filters, heat exchangers, sensors, pumps, mixers, spray nozzles, and dispense heads. These and additional non-limiting examples of actuation components are described, for example, in U.S. Patent Nos. 5,672,832; 5,672,832; 5,678,435; 5,869,766; 6,412,832; 6,601,879; 6,595,240; 6,612,175; 6,652,008; 6,758,104; 6,789,781; 7,063,304; 7,308,932; 7,383,967; 8,561,855; 8,689,817; and 8,726,935, which are incorporated herein by reference except for any express definitions or claims contained in the listed documents.

[0022] The working components may be composed of conductive fluoropolymers, including, for example, perfluoroalkoxyalkane polymers (PFA), ethylene and tetrafluoroethylene polymers (ETFE), ethylene, tetrafluoroethylene and hexafluoropropylene polymers (EFEP), fluorinated ethylene propylene polymers (FEP), tetrafluoroethylene polymers (PTFE), or other suitable polymeric materials. For example, in some embodiments, the conductive fluoropolymer is PFA loaded with a conductive material (e.g., loaded PFA). This loaded PFA includes, but is not limited to, PFA loaded with carbon fiber, nickel-coated graphite, carbon fiber, carbon powder, carbon nanotubes, metal particles, and steel fiber. In various embodiments, the conductive material is present in an amount of about 1×10 per square meter. 8have a surface resistivity level of less than ohms, while non-conductive materials have a surface resistivity level of about 1 x 10 per square ohm. 10 In certain embodiments, the conductive material has a surface resistivity level of greater than about 1×10 ohms per square inch. 9 have a surface resistivity level of less than ohms, while non-conductive materials have a surface resistivity level of about 1 x 10 per square ohm. 9 When the disclosed fluid treatment systems are configured for use in ultra-high purity fluid treatment applications, both the tubing segments and the working components are typically constructed of polymeric materials to meet standards of purity and corrosion resistance.

[0023] In this disclosure, a tubing segment typically refers to any flexible or inflexible pipe or tubing suitable for containing or transporting fluids. The tubing segments are electrically conductive, providing a conductive path along the length of each tubing segment within a fluid circuit. Conductive tubing can be constructed from materials including metals or loaded polymeric materials. Loaded polymeric materials include steel wire, aluminum flakes, nickel-coated graphite, carbon fiber, carbon powder, carbon nanotubes, or polymers loaded with other conductive materials. In some cases, the tubing segments are partially conductive, with a major portion constructed from a non-conductive or low-conductivity material, such as polyester, polycarbonate, polyamide, polyurethane, polyolefin, polystyrene, polyester, polycarbonate, polyketone, polyurea, polyvinyl resin, polyacrylate, polymethylacrylate, and various hydrocarbon and non-hydrocarbon polymers, such as fluoropolymers. Exemplary fluoropolymers include, but are not limited to, perfluoroalkoxyalkane polymers (PFA), ethylene tetrafluoroethylene polymers (ETFE), ethylene, tetrafluoroethylene, and hexafluoropropylene polymers (EFEP), fluorinated ethylene propylene polymers (FEP), and tetrafluoroethylene polymers (PTFE), or other suitable polymeric materials, for example, with secondary coextruded conductive portions. In certain embodiments, the internal fluoropolymer conductive stripes of the tubing segments have widths ranging from about 0.1 to 1 centimeter. In selected embodiments, each tubing segment has a length ranging from about 1 to 100 feet (0.3048 to 30.48 meters). In other selected embodiments, the tubing segments have outer diameters of about 1 / 8 inch (3.18 millimeters) to about 2 inches (5.08 centimeters). In other embodiments, the tubing segments have an outer diameter of about 1.2 x 10 4 ~6.7×10 5In yet another embodiment, the tube segment has a measured resistance of about 2.5 to 4.3 x 10 ohms. 4 It has a measured resistance in ohms.

[0024] FIG. 1 illustrates a fluid processing system 150 according to one or more embodiments of the present disclosure. The system 150 provides a flow path for fluid to flow from a fluid supply 152 to one or more processing stages 156 disposed downstream of the fluid supply. The system 150 includes a fluid circuit 160 that comprises a portion of the flow path of the fluid processing system 150. The fluid circuit 160 includes a pipe segment 164 and a plurality of operating components 168 interconnected via the pipe segment 164. As shown in FIG. 1 , the operating components 168 include an elbow-shaped fitting 170, a T-type fitting 172, a valve 174, a filter 176, a flow meter 178, and a straight fitting 179. However, in various embodiments, the fluid circuit 160 may include additional or fewer operating components 168 in number and type. For example, the fluid circuit 160 may alternatively or additionally include a pump, a mixer, a dispense head, a spray nozzle, a pressure regulator, a flow controller, or other types of operating components. In assembly, the actuating components 168 are connected together by multiple tubing segments 164 that connect to the components 168 at their respective tubing connector fittings 186. The multiple tubing segments 164 and actuating components 168 connected together provide a fluid passageway through the fluid circuit 160 from the fluid supply 152 toward the processing stage 156. In certain embodiments, each actuating component 168 includes a body portion 182 that defines a fluid flow path and one or more tubing connector fittings 186. In some embodiments, at least one tubing connector fitting 186 is an inlet portion for receiving fluid into the body portion 182, and at least another one of the tubing connector fittings 186 is an outlet portion for outputting the fluid received via the inlet portion. For example, the T-type fitting 172 includes one tubing connector fitting 186 that is an inlet portion for receiving fluid from the fluid supply 152 and two tubing connector fittings 186 that are outlet portions for outputting the fluid toward the processing stage 156. The inlet and outlet portions are each connected or connectable to a pipe segment 164 .However, in some embodiments, for example, when the actuating components 168 in the fluid circuit 160 include spray nozzles, only the inlet portion need be connectable to the tubing segment 164. In some embodiments, one or more of the actuating components 168 include a single tubing connector or fitting 179.

[0025] 1 , each body portion 182 is further constructed using an electrically conductive material to form a conductor portion that extends between each of the tubing connector fittings 186 to provide a conductive path between each of the tubing connector fittings 186. In various embodiments, the conductive path is bonded to and uniform within the body portion 182 and is constructed from a conductive polymer material. For example, in some embodiments, the conductor portion is constructed from PFA loaded with an electrically conductive material, including, but not limited to, PFA loaded with carbon fiber, nickel-coated graphite, carbon fiber, carbon powder, carbon nanotubes, metal particles, and steel fiber.

[0026] 2 and 3, the tube segments 164 are partially conductive, having a main or tube portion 187 constructed from a non-conductive or poorly conductive polymer material and a secondary or conductive portion 188 (shown in dashed lines) extending axially along the interior length of the tube portion 187 and constructed from a conductive material. For example, in some embodiments, the tube segments 164 each include a non-conductive fluoropolymer tube portion 187 and a conductive portion 188 formed as a uniform stripe of conductive polymer extending axially and bonded to the non-conductive fluoropolymer main portion 187. In certain embodiments, the tube portions are constructed from PFA with one or more secondary conductive stripes 187 constructed from carbon-containing PFA, which are extruded along the interior length of each tube segment 164 at or near the interior surface of the tube segment 164.

[0027] As shown in FIG. 1 , each of the actuating components 168 includes a bridging component for conductively connecting the respective conductive path of the body portion 182 to the conductive portion 187 (shown in FIGS. 2 and 3 ) of the tubing segment 164 connected to the actuating component 168. Thus, in certain embodiments, the connected actuating components 168 and tubing segments 164 form an electrical pathway along the entire fluid circuit 160, eliminating conductive breaks between the tubing segments 160. A circuit diagram 190 is superimposed on the fluid circuit 160 to illustrate the electrical pathway. In various embodiments, the conductive material is approximately 1×10 per square meter. 10 have a surface resistivity level of less than ohms, while non-conductive materials have a surface resistivity level of about 1 x 10 per square ohm. 10 In certain embodiments, the conductive material has a surface resistivity level of greater than about 1×10 ohms per square inch. 9 have a surface resistivity level of less than ohms, while non-conductive materials have a surface resistivity level of about 1 x 10 per square ohm. 9 It has a surface resistivity level above ohms.

[0028] In certain embodiments, to mitigate static charge buildup, one or more actuation components 168 are electrically connected to ground 194 via one or more mounting fixtures 198. The ground mounting fixtures 198 continuously dissipate static electricity as it builds up in the fluid circuit 160 by providing a path from the conductive pathway 190 to ground 194.

[0029] 2 and 3 illustrate an example of an actuation component 210 according to one or more embodiments of the present disclosure. FIG. 2 illustrates a fitting 214, more specifically, an actuation component 210 that is a three-way connector having a "T" shape (e.g., a T-shaped fitting). FIG. 3 illustrates a valve 218. The T-shaped fitting 214 includes an electrically conductive body portion 222 and three connector fittings 226 extending outwardly from the body portion 222. In certain embodiments, the outer surfaces of the connector fittings include a structural surface 270. The valve 218 includes an electrically conductive body portion 230 and two connector fittings 227 extending outwardly from the body portion 230. In certain embodiments, the outer surfaces of the connector fittings include a structural surface 270.

[0030] In various embodiments, connector fittings 226 and 227 are substantially the same design. As noted above, in various embodiments, body portions 222, 230 are constructed using a conductive polymer material. For example, body portions 222 or 230 can be constructed from a conductive carbon-loaded fluoropolymer, including, but not limited to, PFA, ETFE, FEP, and PTFE.

[0031] FIG. 4a illustrates a straight connector fitting 400 for connecting two tubing segments. The connector fitting 400 includes a shoulder region 402 adjacent to a body portion 404 of an actuation component and extends outward to form a neck region 406, a threaded region 406a, and a nipple portion 406b. The tubing segment 164 is received by the nipple portion 406b, which in certain embodiments may be configured as a FLARETEK® fitting, for example. The connector fitting 400 also includes an attachment feature 408, which is a conductive material that is conductively connected to the body portion 504 for attachment to an external electrical contact and then to ground. For example, the attachment feature 408 may be connected to a grounded electrical contact to configure the actuation component connector fitting 400 for ESD mitigation.

[0032] In the embodiment shown in FIG. 4b, the connector fitting 400 includes a connector fitting nut 410 for engaging the threaded region 406a to secure the tubing segment 164. In some embodiments, the fitting nut can be, for example, a compression nut. When the fitting nut 410 is rotated and tightened onto the threaded region 406a, the tubing segment 164 engages the connector fitting, and the internal conductive stripe conductively connects the conductive portion to the nipple portion 406b, forming a leak-proof seal between the tubing and the connector fitting. In one or more embodiments, the fitting nut 410 has a generally cylindrical shape with an inner surface including threads 410a for mating with the threaded region 406a. Additionally, the fitting nut 410 can have a structured outer surface, such as the ribs 270 shown in FIGS. 2 and 3. The ribs are symmetrically arranged around the outer surface to mate with a wrench or locking device for tightening or loosening the fitting nut 410 on the threaded region 406a.

[0033] In one or more embodiments, fitting nut 410 is constructed from a polymeric material. For example, in certain embodiments, fitting nut 410 is constructed from PFA, polyaniline, or other suitable polymers.

[0034] In some embodiments, the connector fitting 400 is a conductive polymer material, such as, for example, carbon-filled PFA, or other suitable conductive polymer formed using conventional molding processes.

[0035] In certain embodiments, when the connector fitting 400 is assembled with the pipe segment 164, the fitting nut 410 contacts the outer surface of the pipe segment 164 at the nipple forward portion 406b, creating a continuous fluid pathway between the pipe segment 164 and the connector fitting 400. When the fitting nut 410 is rotated and tightened, an O-ring 412 disposed between the fitting nut 410 and the shoulder portion 402 contacts the outer surfaces of both the fitting nut and the shoulder portion, providing a leak-proof connection.

[0036] In various embodiments, the O-ring 360 is constructed from a polymeric material such as PFA, or other polymers or elastomers. Those skilled in the art will understand that while the particular embodiments shown in Figures 2, 3, and 4 have the same connector fitting, in some embodiments, the connector fitting may have different sizes, may have different designs such as a step-down or step-up fitting, or may be located on different types of actuation components 210.

[0037] 5a-5e illustrate several embodiments of an actuating component 500. The actuating component 500 includes a body portion 504, a tube connector fitting 520, and a fitting nut 508. In one or more embodiments, the actuating component 500 further includes an actuating element 506 within the body. The actuating element 506 in various embodiments broadly includes any suitable structure, electronics, or other material for configuring the actuating component 500 to perform various operations. For example, in some embodiments, the actuating element 506 is a mixer, sensor, filter, pump, heat exchanger, or other suitable element. Thus, the actuating component 500 can be configured to perform various processes or tasks within a fluid circuit.

[0038] Body portion 504 includes conductive PFA extending between each of tube connector fittings 520, which forms electrical contact between each of tube connector fittings 520 and the interior conductive stripes of tube segments 522a and 522b. In Figures 5b and 5c, in one or more embodiments, the conductive portion of the tube segment is a narrow interior stripe of conductive material bonded to and uniform with the non-conductive polymer material of the tube segment. Figure 5b illustrates a tube segment with four interior conductive stripes 524a-524d. In another embodiment, Figure 5c illustrates a tube segment with eight interior conductive stripes 524a-524h. In yet another embodiment, Figure 5d illustrates a tube segment with eight interior conductive stripes 524a-524h and two exterior conductive stripes 526a and 526b. In a similar construction of a tube segment with internal and external stripes, FIG. 5e shows a tube segment with eight internal conductive stripes 524a-524h and two external conductive stripes 526a and 526b.

[0039] As noted above, in various embodiments, actuation component 500 is connected to tubing segments 522a and 522b at respective connector fittings 508. Connector fittings 508 form an electrical path from conductive portions 522a and 522b of the tubing segments through connector portion 508 and across body portion 504.

[0040] In various embodiments, as shown in FIG. 5 a, the body portion 504 includes an attachment feature 528. In one or more embodiments, the attachment feature 528 is a piece of conductive material that is conductively connected to the body portion 504 for attachment to an external electrical contact and then grounded. For example, the attachment feature 528 can be connected to a grounded electrical contact to configure the actuation component 500 for ESD mitigation. In one or more embodiments, the attachment feature 528 is a threaded connector boss for attachment to a nut or other threaded connector. In some embodiments, the attachment feature 528 is a tab, a threaded hole, or other suitable feature for connecting to an electrical contact. However, in certain embodiments, the attachment feature 528 can be configured for an interference fit, a snap fit, a friction fit, or other fitting method for fitting with an electrical contact.

[0041] FIG. 6a illustrates one embodiment of an active component that is a filter. This isometric view of filter 600 includes a housing 602, two conductive end caps 604 and 606, and an outer conductive sleeve 608. Housing 602 includes an internal filter element (not shown), which in some embodiments is a replaceable component, while in other embodiments, the internal filter element is a fixed, non-replaceable component. In various embodiments, housing 602 can be a polymeric material, and in other embodiments, a conductive polymer, such as, for example, conductive carbon-filled PFA, as described above. Both conductive end caps 604, 606 can be a conductive material, such as, for example, conductive carbon-filled PFA. Each end cap 604, 606 includes a fitting for connecting the end cap to housing 602. In some embodiments, the connection can be removable, while in other embodiments, the connection can be fixed or permanent. Additionally, each end cap 604, 606 includes one or more connector fittings, as described above, to connect the respective end cap to a pipe segment (also not shown) to provide both a connection path and a fluid passage from the pipe segment through one end cap and the housing to another end cap and pipe segment. In certain embodiments, the connector fitting includes, for example, a nipple portion 610, a threaded portion 612, a shoulder portion 614, and a fitting nut 616, as described above, to provide a conductive connection and a leak-proof passage from the pipe segment and the filter 600. Additionally, the connector fitting may include an O-ring (not shown). A conductive sleeve 608 extends over the exterior surfaces of both the housing 602 and the conductive end caps 604, 606. The sleeve 608 is a conductive polymer material, such as, for example, carbon-filled PFA, that provides a conductive connection between the end cap 604 and the housing 602. In some embodiments, the sleeve 608 is a shrink-wrap polymer that can be disposed on the exterior of the housing 602 and the end caps 604, 606 and connected to the exterior surfaces by applying heat to the sleeve using conventional equipment and processes. Optionally, one or both of the end caps 604, 606 may include mounting features (not shown).In one or more embodiments, the mounting feature is a piece of conductive material conductively connected to one or both end caps 604, 606 for attachment to an external electrical contact and thereby to ground. For example, the mounting feature can connect to a grounded electrical contact to form a filter for ESD mitigation. In one or more embodiments, the mounting feature is a threaded connector boss for attachment to a nut or other threaded connector. In some embodiments, the mounting feature is a tab, threaded hole, or other suitable feature for connecting to an electrical contact. However, in certain embodiments, the mounting feature can be configured for an interference fitting, a snap fitting, a friction fitting, or other fitting method with an electrical contact.

[0042] 6b, filter 600 includes a drain fitting 618 and a drain plug 620. If at least one of drain fitting 618 and drain plug is a conductive material, one or both of these components can be connected to ground to provide ESD mitigation.

[0043] FIG. 7a also illustrates one embodiment of an active component that is a filter. This isometric view of filter 700 includes a housing 702, a conductive end cap 704, and an outer conductive sleeve 708. Housing 702 includes an internal filter element (not shown), which in some embodiments is a replaceable component, while in other embodiments, the internal filter element is a fixed, non-replaceable component. In various embodiments, housing 702 can be a polymeric material, and in other embodiments, a conductive polymer, such as, for example, conductive carbon-filled PFA, as described above. Conductive end cap 704 can be a conductive material, such as, for example, conductive carbon-filled PFA. Conductive end cap 704 includes fittings for connecting the end cap to housing 702. In some embodiments, the connection can be removable, while in other embodiments, the connection can be fixed or permanent. Additionally, end cap 704 includes one or more connector fittings 710 for connecting the end cap to a tubing segment, as described above, to provide both a connection path and a fluid path from the tubing segment and conductor fitting through the housing to another conductor fitting and tubing segment. In certain embodiments, the connector fitting includes a nipple portion, a threaded portion, a shoulder portion, and a fitting nut, for example, as described above, to provide a conductive connection and a leak-proof fluid passage from the tubing segment 164 and the filter 700. Additionally, the connector fitting may include an O-ring (not shown). A conductive sleeve 708 extends over the exterior surfaces of both the housing 702 and the conductive end cap 704. The sleeve 708 is a conductive polymer material, such as, for example, carbon-filled PFA, that provides a conductive connection between the end cap 704 and the exterior of the filter 700. In some embodiments, the sleeve 708 is a shrink-wrap polymer that can be disposed on the exterior of the housing 702 and the end cap 704 and connected to the exterior surfaces by applying heat to the sleeve using conventional equipment and processes. Optionally, the end cap 704 may include an attachment feature (not shown). In one or more embodiments, the attachment feature is a piece of conductive material that is conductively connected to the end cap 704 for attachment to an external electrical contact and thereby grounding.For example, the mounting features can be connected to a grounded electrical contact to configure the filter for ESD mitigation. In one or more embodiments, the mounting features are threaded connector bosses for attachment to nuts or other threaded connectors. In some embodiments, the mounting features are tabs, threaded holes, or other suitable features for connecting to electrical contacts. However, in certain embodiments, the mounting features can be configured for interference fittings, snap fittings, friction fittings, or other fitting methods with electrical contacts. In certain embodiments, the filter 700 includes a drain fitting 718 and a drain plug (not shown). If at least one of the drain fitting 718 and the drain plug is made of a conductive material, one or both of these components can be connected to ground to mitigate ESD. FIG. 7a also illustrates an optional retaining clamp including clamping elements 721, 722, and 723.

[0044] FIG. 7 b shows an embodiment of an end cap 704 that includes a conductive polymer portion 730 and a natural polymer portion 732 . [Co-extrusion processing] Tubing segments with conductive polymer stripes as described in this disclosure can be fabricated using various coextrusion processes. For example, tubing segment 800a shown in FIG. 8a includes conductive stripes 802a and 804a on the exterior or outer diameter of the tubing segment and conductive stripe 806a on the interior or inner diameter of the tubing segment. In another embodiment, FIG. 8b illustrates tubing segment 800b with conductive stripe 802b on the interior of the tubing segment, where conductive stripe 802b is a spiral stripe extending along the axial length of the tubing segment. In another embodiment, FIG. 8c illustrates tubing segment 800c with conductive stripes 802c and 804c on both the exterior and interior of the tubing segment, where conductive stripes 802c and 804c are spiral stripes extending axially along the length of the tubing segment. In yet another embodiment, FIG. 8d illustrates tubing segment 800d with conductive stripe 802d on the exterior of the tubing segment, where conductive stripe 802d is a spiral stripe extending axially along the length of the tubing segment.

[0045] 9 is a digital image of a pipe segment 900 that includes eight interior stripes, which are black stripes within the image, that are joined together to form a uniform stripe within the rest of the pipe segment.

[0046] Figure 10 is a digital image of an extrusion apparatus for providing one or more tubing segments as described in this disclosure. Figure 10 shows a non-conductive extruded polymer (PFA) feed 1000 and a conductive extruded polymer (PFA / carbon black polymer) feed 1010 fed perpendicularly to a tool 1020 that extrudes a stripe 1030 onto the inner diameter of a tubing segment 1050 and onto both the inner and outer diameters of the tubing segment. One skilled in the art will readily determine the specific extrusion parameters that will provide a tubing segment with a uniform conductive stripe bonded to the non-conductive portion of the tubing segment.

[0047] [Example 1: Static generated test] This example measured the amount of static electricity generated by flowing deionized water through a tubing segment containing conductive and non-conductive materials as shown below in Table 1. The static electricity measurements were made using known methods for collecting and measuring the generated charge with a Faraday cup.

[0048] Figure 11 is a digital image showing the Faraday cup apparatus 1100 used in this example. Briefly, deionized water 1110 passes through an actuating element 1130 and a grounded tubing segment 1120, then is collected in the Faraday cup. The Faraday cup 1150 included a cover that was not visible in the image when the data for this example was collected. Exemplary data provided by the imaged data are shown in Charts 1-4 below.

[0049] Chart 1 (Table 1) and Chart 2 (Table 2) graphically show the difference in static charge generation between a PFA tubing segment and a stainless steel (SS) tubing segment of the same diameter under the same flow conditions. The PFA tubing segment generated substantially more static charge (approximately 1600 nC) compared to the static charge generated by the SS tubing segment (approximately 80 nC).

[0050] [Table 1]

[0051] [Table 2]

[0052] Chart 3 (Table 3) and Chart 4 (Table 4) graphically show the difference in static charge generation between a PFA / ID and OD striped tubing segment and a PFA / ID striped tubing segment with the same diameter under the same flow conditions. The PFA / ID and OD striped tubing segment generated less static charge (approximately 43 nC) compared to the static charge generated by the PFA / ID striped tubing segment (approximately 115 nC).

[0053] [Table 3]

[0054] [Table 4]

[0055] Table 1 summarizes the measured amounts of static electricity generated by the various pipe segments tested in this example. These results are also displayed graphically in Chart 5.

[0056] [Table 5]

[0057] [Table 6]

[0058] The description of various embodiments of the present disclosure has been presented for purposes of illustration, but is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terms used herein have been selected to explain the principles of the embodiments, practical applications or technical improvements to technology found in the market, or to enable those skilled in the art to understand the embodiments disclosed herein.

Claims

1. 1. A fluid circuit for mitigating electrostatic discharge, the fluid circuit comprising: a plurality of actuating components, each said actuating component having a conductive body portion defining a fluid passage; a plurality of tubing segments connecting a plurality of said working components; It is equipped with Each of the pipe segments comprises: (i) a non-conductive polymer portion that is substantially non-conductive; (ii) one or more internal conductive stripes disposed on the interior surface of said non-conductive polymeric portion; (iii) one or more external conductive stripes disposed on an outer surface of said non-conductive polymeric portion; It is equipped with the internal conductive stripe is conductively connected to the conductive body portion of the actuation component; fluid circuit.

2. the one or more inner conductive stripes and the one or more outer conductive stripes extend axially to an end of each of the pipe segments; The fluid circuit of claim 1 .

3. one or more of the internal conductive stripes are spiral stripes; 3. A fluid circuit according to claim 1 or 2.

4. one or more of the external conductive stripes are spiral stripes; The fluid circuit according to any one of claims 1 to 3.

5. At least one of the plurality of actuation components further includes an attachment feature configured to electrically connect the conductive body portion to ground. The fluid circuit according to any one of claims 1 to 4.

Images