Static pressure pipe device and system

Abstract

Static pressure measuring device, the device comprising: a housing (510) defining a passage (111) for the flow of gases; a static pressure tube (522) having an opening (522a), the static pressure tube (522) being attached to a side of the housing (510) at a connection point and extending into the passage (111) such that the opening (522a) is disposed within the flow of gases; a connecting part (511) arranged at the connection point, wherein: the connecting part (511) comprises an outer tube (1210) fixed to the exterior of the static pressure tube (522), the outer tube (1210) has a flange (1212) arranged on the lower portion of the outer tube (1210), the connector (511) further comprises a boss (1214) attached to the housing (510) for receiving the static pressure tube (522) and the outer tube (1210) and a nut (1216) arranged around the outer tube (1210) and configured to compress the flange (1212) against the boss (1214); and the flow of gases around the static pressure tube (522) increases the temperature of the static pressure tube (522).

Description

BACKGROUND OF THE INVENTION

[0001] This invention relates to gas measuring devices and, more particularly, to devices for sensing the static pressure of exhaust gas.

[0002] In various applications, it is desirable to measure the static pressure of a gas flowing through a housing. In engine exhaust streams, whether within the engine or on the engine aftertreatment system, static pressure sensors are commonly used to determine the exhaust gas recirculation fraction, exhaust manifold pressure, or the pressure drop across an exhaust treatment device or the backpressure generated by such a device. One such device is a diesel particulate filter, the use of which is becoming increasingly widespread due to increasingly stringent environmental regulations regarding diesel engine emissions. Accurate static pressure measurements are important for the proper functioning of engine and aftertreatment system components, as inaccurate measurements can result in engine or component failure.

[0003] The static pressure is measured by inserting a gas sampling tube into the wall of the housing, pipe, venturi nozzle or other component through which the exhaust gases pass, with one end of the tube, with an opening, arranged on the wall and the other end operatively connected to a pressure sensor.

[0004] It is common practice to install static pressure sampling lines upstream and downstream of a diesel particulate filter to determine the condition of the filter, i.e., how much soot or other particulate matter has been captured by the filter and is still present in the filter. Excessive particulate matter can lead to poor engine performance or uncontrolled particulate oxidation on the filter, damaging or destroying the filter and surrounding components.

[0005] Exhaust gases generally contain a variety of chemical components, including soot, hydrocarbons, water, carbon oxides, and carboxylates, each of which can potentially, and often actually, escape from suspension and form a deposit on some component of the exhaust system. One of the problems associated with static pressure sampling tubes is the formation of deposits at their openings, which distorts the pressure sensed by the sensor attached to the tube. In the case of diesel particulate filter sampling tubes, this can cause the engine control system to unduly delay filter regeneration (a controlled oxidation of the particulate matter on the filter), leading to filter damage or failure.

[0006] Further static pressure pipes are known from JP H07-224 636 A, JP 2005-256 626 A, JP 2003-42 885 A and DE 821 745 B. SUMMARY OF THE INVENTION

[0007] The present invention has been developed in response to the current state of the art and, in particular, in response to the problems and needs in this field that have not yet been fully solved.

[0008] Accordingly, the present invention has been developed to provide a static pressure piping apparatus and a static pressure piping system that overcomes many or all of the disadvantages of the prior art.

[0009] A static pressure measuring device according to the present invention is defined in claim 1. A static exhaust pressure measuring system according to the present invention is defined in claim 7. Further preferred embodiments are set out in the dependent claims.

[0010] According to one aspect of the invention, a static pressure measuring device comprises a passage configured to receive the flow of a gas and a static pressure sampling device arranged at the passage. The sampling device is operatively connected to a static pressure sensor configured to measure the static pressure of the gas. A thermal mechanism is provided, wherein the thermal mechanism is configured to heat the static pressure tube.

[0011] According to another aspect of the invention, a static pressure measuring device comprises a housing defining a passage for the flow of gases and a static pressure tube having an opening, the static pressure tube being attached to a connection point on one side of the housing.

[0012] The tube extends into the passage with the opening located within the flow of gases so that the flow of gases around the static pressure tube increases the temperature of the tube.

[0013] In one embodiment, the gases are exhaust gases, a particulate filter is disposed downstream of the static pressure pipe, a static pressure measuring device is disposed downstream of the particulate filter, and the device and the pipe cooperate to determine the static pressure drop across the particulate filter. A regenerative catalytic device may be disposed upstream of the static pressure pipe. Regeneration of the catalytic device increases the temperature of the exhaust gases and the static pressure pipe, thereby eliminating particulate buildup on the orifice.

[0014] In one embodiment, a connector is arranged at the connection point. The connector comprises an outer tube secured to the exterior of the static pressure tube, with a flare disposed on the lower portion of the outer tube. A boss is attached to the housing for receiving the static pressure tube and the outer tube, and a nut is disposed around the outer tube. The nut is configured to compress the flare against the boss.

[0015] According to another aspect of the invention, a method for measuring the static pressure of a gas stream comprises forcing the gas through a housing passage, the housing passage having an outer wall, and sampling the gas at a sampling point located inside the housing passage and at a substantial distance from the outer wall. In one embodiment, the method comprises raising the temperature of the gas and, by utilizing the elevated temperature of the gas, removing a buildup of particles formed at the sampling point.

[0016] Throughout this description, references to features, advantages, or similar language do not imply that all features and advantages feasible with the present invention are or should be present in every single embodiment of the invention. Rather, references to features and advantages are intended to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Discussion of features and advantages, as well as similar language, throughout this description may, but do not necessarily, refer to the same embodiment.

[0017] The described features, advantages, and characteristics of the invention may be combined in one or more embodiments in any suitable manner. Those skilled in the art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention. These features and advantages of the present invention will become more fully apparent from the following description and the appended claims, or may be learned by practice of the invention as hereinafter pointed out. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to readily understand the advantages of the invention, a more detailed description of the invention will be given by reference to specific embodiments illustrated in the accompanying drawings, which merely depict typical embodiments of the invention and are not to be considered as limiting the scope thereof, wherein Fig. Figure 1 is a cross-sectional view of a prior art static pressure pipe device; Fig. Figure 2 is a cross-sectional view of an embodiment of a static pressure pipe device according to the present invention; Fig. 3 is a perspective view of an exhaust gas treatment and sensing device according to the prior art; Fig. 4 a cross-sectional view of the device of Fig. 3 along the line 4'4; Fig. 5 is a cross-sectional view of an embodiment of an exhaust treatment and sensing device according to the present invention; Fig. 6 a cross-sectional view of the device of Fig. 5 is along line 6-6; Fig. 7 is a cross-sectional view of another embodiment of an exhaust treatment and sensing device according to the present invention; Fig. 8 is a cross-sectional view of another embodiment of an exhaust treatment and sensing device according to the present invention; Fig. 9 is a cross-sectional view of another embodiment of an exhaust treatment and sensing device according to the present invention; Fig. 10 is a schematic view of an embodiment of an exhaust treatment and sensor system according to the present invention; Fig. 11 is a schematic flow diagram illustrating one embodiment of an exhaust gas treatment, sensing and regeneration method according to the present invention; Fig. 12 is a cross-sectional view of one embodiment of a static pressure tube / housing fitting according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] Throughout this specification, references to "one of the embodiments," "an embodiment," or similar phrases indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Occurrences of the phrases "in one of the embodiments," "in an embodiment," and similar phrases throughout this specification may, but do not necessarily, refer to the same embodiment throughout.

[0020] The described features, structures, or characteristics of the invention may be combined in one or more embodiments in any suitable manner. In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the invention. However, one of ordinary skill in the art will recognize that the invention may be practiced without one or more of the specific details, or with different methods, components, materials, etc. In other instances, well-known structures, materials, or processes are not shown or described in detail to avoid obscuring aspects of the invention.

[0021] Fig. Figure 1 shows a prior art static gas pressure device 100 comprising: a cylindrical gas flow housing 110 defining a flow passage 111, a gas flow indicated by arrow 112 through the housing, a static pressure tube 114 having a bleed end 114a disposed on one side of the housing 110, the bleed end 114a being open to sample the gas flowing through the passage 111. The other end 114b of the static pressure tube 114 is attached to a static pressure sensor 116 that senses the static pressure of the gas.

[0022] As known to those skilled in the art, a fluid tends to flow slower along the walls of its passage than at the center, making the center of the gas flow faster than the flow at the edges. Deposits tend to form more easily in areas of low flow, making the tapping end 114a of the tube, located at the edge of the flow, more susceptible to deposit formation. Furthermore, there is little or no net flow through the interior of the length of the tube 114, making the open tapping end 114a even more susceptible to deposit formation.

[0023] The problem is exacerbated by the fact that, in warm or hot gas, the tube 114, including the opening 114a, is cooler than the gas because the tube 114 is located in the cooler ambient air and on the side of the housing 110, which is also cooler than the gas. This can make the open sampling end 114a even more susceptible to the formation of deposits due to thermophoretic forces, i.e., forces exerted on particles in a temperature gradient.

[0024] Fig. Figure 2 shows an embodiment of a static gas pressure device 200 according to the present invention. The device 200 is similar in construction to the device 100, except that the static pressure tube 214 of the device 200 extends into the gas stream 212, causing its extraction end 214a to be located well within the gas stream 212. In this embodiment, the hot gas stream 212 heats the tube 214 to a temperature that is closer to the temperature of the gas stream 212 than with a configuration of the tube 214 and the opening 214a as shown in Fig. 1. This reduces thermophoretic forces that drive particles toward the orifice, thus reducing particle deposition on it. Furthermore, orifice 214a is located at or near the center of stream 212, in a high-flow region, further reducing the formation of deposits on orifice 214a.

[0025] With specific reference to engine exhaust systems, Fig. 3 and Fig. 4 illustrates a prior art exhaust treatment device 300 having a housing 310 containing a catalytic converter 312 and a diesel particulate filter 314. The housing 310 receives, through an inlet 316, exhaust gases from a diesel engine (not shown) passing through the housing 310 generally in the direction of arrow 318, including the catalytic converter 312 and the particulate filter 314, as well as other emissions or acoustic treatment devices that may be contained within the housing 310. While the general direction of the exhaust gas is indicated by arrow 318, some turbulence is known to inevitably result from the placement of components of the system, such as the catalytic converter 312, in the exhaust stream. The exhaust gas exits the housing 310 through an outlet 320, either to further treatment devices or to the atmosphere. For structural reasons, brackets or clamps 321 are used on the housing 310.

[0026] The device 300 includes static pressure sampling tubes 322 and 324, respectively located upstream and downstream of the diesel particulate filter 314. Each tube 322 and 324 has a sampling end 322a and 324a located on the side of the housing 310, with the sampling ends 322a and 324a having openings for sampling the gas stream 318. The other ends of the tubes 322b and 324b are attached to a pressure sensor 326, which senses the pressure differential between the upstream and downstream sides of the particulate filter 314.

[0027] The gas contained in tubes 322 and 324 is essentially static (unmoved), except for slight movement and compression due to exhaust pulsations from engine operation, primarily the exhaust cycles of the pistons and cylinders, which creates slight gas movement through ports 322a and 324a.

[0028] As described in the Background section, particulate deposits tend to form at orifices 322a and 324a due to gas components emerging from suspension and depositing on orifices 322a and 324a due to the lower flow velocity near the wall of housing 310, as well as thermophoretic forces resulting from the temperature gradient between hot gas 318 and cooler housing and tubes 322 and 324.

[0029] The rate of particulate deposition on openings 322a and 324a depends on factors such as engine size, exhaust temperature, and ambient temperature, i.e., the outside air temperature. The larger the engine, the more exhaust gas and pollutants are generally produced, with correspondingly higher deposition rates. Deposition rates also increase with a decrease in ambient temperatures, as colder ambient temperatures create a higher temperature gradient between the gas stream 318 and the housing 310 and the tubes 322 and 324.

[0030] A primary indicator of the rate of deposition of particles on the discharge end 322a of the tube is therefore the following equation: ΔT / T

[0031] Where AT is the temperature difference between the withdrawal end 322a and the gas 318 (temperature gradient), and T is the total temperature.

[0032] Generally, particulate deposits on the upstream sampling pipe 322 are a greater problem than on the downstream pipe 324 because the particulate filter 314 removes many or most of the particulate and other deposit-forming materials in the exhaust gas before the exhaust gas reaches the downstream pipe 324.

[0033] Fig. 5 and Fig. 6 illustrate an embodiment of a static pressure extraction device 500 according to the present invention. The device 500 is similar in construction to the device 300, except that instead of the upstream static pressure tube terminating at 322a on the wall of the housing 310, the device 500 has an upstream static pressure tube 522 extending through a connector 511 into the interior of the housing, into the gas stream 518, such that its open extraction end 522a is disposed within the gas stream 518. In this embodiment, the hot gas stream 518 heats the tube 522 to a temperature that is closer to the temperature of the gas stream 518 than with a configuration of the tube 522 and the opening 522a as in Fig. 3 and Fig. 4. This reduces thermophoretic forces driving particles toward orifice 522a and thus reducing particulate deposition thereon. Additionally, orifice 522a is located at or near the center of stream 518 in a high-flow region, further reducing deposit formation on orifice 522a. Downstream sampling tube 524 may or may not be configured similarly to orifice 522, as fewer particulate matter and exhaust constituents are present to form deposits on orifice 524a after the exhaust passes through particulate filter 514, reducing the need to prevent deposit formation thereon.

[0034] The sampling tube end 522a may be located at locations other than the center of the gas flow 518 while still maintaining the advantages of the invention. Fig. Figure 7 shows an embodiment of the invention (seen in the same orientation and at the same location as in Fig. 6), which is similar to the device 500 in every respect, except that its upstream extraction tube 722 extends almost entirely across the inner diameter of the housing 510, so that its open extraction end 722a is located near the opposite side of the housing 510 from where the tube 722 enters the housing 510. Although the exhaust gas flow 518 may be slower in the region of the extraction end 722a, the Fig. 7 still allows the heating of the pipe 722 by interaction with the hot exhaust gas 518, thereby reducing thermophoretic forces and the corresponding particle deposition.

[0035] The scope of the invention also includes embodiments such as those in Fig. 8, which is similar in all respects to the device 500, except that its upstream sampling tube 822, instead of extending radially straight into the interior of the housing 510, curves around the interior near the wall of the housing 510 and terminates at an open sampling end 822a located near the point at which the sampling tube 822 enters the housing 510. Although the sampling end 822a is not far from the locations where existing sampling tubes have their openings (for example, the one shown in Fig. 4), less deposits form on the opening 822a. A substantial portion of the tube 822 is disposed inside the housing 510, providing heating of the tube 822—along with its open extraction end 822a—through interaction with the hot exhaust gases, thus reducing thermophoretic forces.

[0036] Embodiments such as those in Fig. 8 may be advantageous when, for example, the housing 510 has a small diameter, requiring a bend in the tube 822 inside the housing 510 to expose a substantial portion of the tube 822 to the exhaust stream 518.

[0037] What is considered a "substantial" portion of tubing extending into the interior of the housing depends on the particular application and the desired characteristics of the system. As will be apparent to one of ordinary skill in the art in light of this disclosure, any portion of tubing beyond a minor portion used for attachment to the housing—that is, any portion of tubing extending into the interior of the housing for the specific purpose of harnessing heating from the exhaust gases—will contribute to reducing deposit formation and thus may be considered "substantial." Experiments have shown that in an application where the outside diameter of the sampling tube is 0.79 cm (5 / 16 inch), there is a substantial benefit to placing at least 7.62 cm (3 inches) of tubing inside the housing, although a lesser length will also provide some benefit.

[0038] Embodiments of the present invention described so far enable a reduction of the thermophoretic forces by heating the upstream sampling tube, wherein the heating is carried out by placing a substantial portion of the sampling tube inside the exhaust housing. However, the heating can also be carried out in other ways within the scope of the invention, for example as described in Fig. 9 shown embodiment. The Fig. The device shown in Figure 9 is similar in all respects to the device 500, except that instead of the upstream sampling tube extending into the interior of the housing 510, the upstream sampling tube 922 of the device extends into Fig. 9 has an open sampling end 922a that terminates at the wall of the housing 510, as in existing devices. A heating wire 950 is wrapped around the tube 922 between the static pressure sensor 926 and the housing 510 so that it heats the tube 922 and its corresponding sampling end 922a, thereby reducing thermophoretic forces and the formation of deposits from the gas 518 at the sampling end 922a. Other thermal mechanisms designed to heat the upstream sampling tube may also be used within the scope of the invention.

[0039] Heating the tube 922 with the wire 950 may require equipment that is more complex to implement than extending the tube into the interior of the housing, as in Fig. 5, but may also have certain advantages, such as the ability to heat the tube 922 to a precise temperature within a wide range, rather than depending on the temperature of the exhaust gas 518. The Fig. The device shown in Figure 9 allows heating of the tube 922 to a temperature which exceeds that of the exhaust gas 518, so that reverse thermophoretic forces are generated.

[0040] Fig. 10 is a schematic diagram of device 500 operatively connected to an engine 1010 that produces exhaust gas catalyzed by catalyst 512. The exhaust gas moves, as indicated by arrows 518, past upstream static pressure sampling pipe 522, through diesel particulate filter 514, past downstream static pressure sampling pipe 524, and from there into the atmosphere. Other components or devices, not shown, may be included in the exhaust treatment system. A regeneration mechanism 1012 is operatively connected to the catalytic device 512 for the purpose of regenerating device 512. Generally, regeneration involves heating device 512 to a temperature such that accumulated materials on device 512 are fully or partially oxidized or otherwise removed.Regeneration is known to require an increase in temperature and is often accomplished by the regeneration mechanism 1012 initiating metering, i.e., injecting fuel or another flammable substance into the exhaust stream, thereby heating the gas and regenerating the device 512. Metering may occur at a range of points along the exhaust stream, for example, in the turbocharger of the engine 1010 or even within the cylinders. Such regenerations may also be accomplished in conjunction with regenerations of the diesel particulate filter 514 or separately.

[0041] Depending on the application, regenerations of device 512 may also occur spontaneously. For example, systems used in long-haul trucks may reach regeneration temperatures without dosing.

[0042] Regeneration of the catalytic device 512, either by initiating regeneration through the regeneration mechanism 1012 or spontaneously, increases the temperature of the interior of the housing 510 downstream of the device 512 and thus also serves to regenerate the open extraction end 522a of the extraction tube 522. Slight deposit formation is likely to occur at the extraction end 522a, although the deposits will be reduced compared to existing devices. Due to its location within the exhaust stream 518, the extraction end 522a utilizes temperatures resulting from the regenerating catalytic device 512 and oxidizes or otherwise removes any deposits formed.

[0043] As previously described, by locating the sampling end of the tube at various locations within the gas stream, the temperatures of the gas stream can be utilized, both separately from and during regeneration, although the benefit may vary with the radial variation of temperatures within the housing 510. Furthermore, the sampling port 522a of the tube may be regenerated at locations other than downstream of the catalytic device 512, for example, downstream of each exhaust treatment component being regenerated, or simply within the exhaust stream, with regeneration occurring when the temperature increases due to high engine load or other factors.

[0044] The following schematic flow diagram, like the preceding schematic diagram, is generally interpreted as a logical flow diagram. As such, the depicted sequence and steps indicate one embodiment of the presented method. Other steps and methods are conceivable which are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated method. Furthermore, the format and symbols used are provided for the purpose of explaining the logical steps of the method and are understood to be non-limiting to the scope of the method. While various types of arrows and lines may be used in the flow diagrams, it is understood that these do not limit the scope of the corresponding method.Some arrows or other connecting elements may be used to indicate only the logical flow of the procedure. For example, an arrow may indicate a wait or monitoring period of indefinite duration between enumerated steps of the illustrated procedure. Additionally, the order in which a particular procedure occurs may or may not strictly follow the order of the corresponding steps shown.

[0045] Fig. 11 illustrates one embodiment of a method 1100 for measuring static pressure in accordance with the present invention. The method 1100 depicts an embodiment used for measuring the static pressure of exhaust gases produced by a diesel engine, but is generalizable for use in any gas stream. As illustrated, the method 1100 begins in a block 1110, and the exhaust gases are forced through an exhaust housing, block 1112, such as housing 510. A controller or other device, or a person, then determines whether regeneration of the catalytic device 512 is required, block 1114. If so, regeneration of the device is initiated, block 1116, which also results in regeneration of the sample tube end 522a. Such regeneration may also occur spontaneously due to engine operation.After initiating regeneration, or if regeneration is not required, the exhaust gases are forced through the catalytic device 512, block 1118, and are then sampled using a tube heated by the gases, block 1120, the open end of the tube, for example, sample tube end 522a, being located a substantial distance inside the housing 510, measured by the length of the tube 522 between the end 522a and the point where the tube 522 is connected to the housing 510.

[0046] After the static pressure is removed, the gases are forced through the diesel particulate filter 514, block 1122, the gases are again removed from the pipe 524, block 1124, the sensor 526 determines the pressure drop across the filter 514 due to the pressure removal from the pipes 522 and 524, the gases escape to the atmosphere, block 1126, and the method ends, 1128.

[0047] In other applications, the method 1100 may be simplified. For example, if only the static pressure of a flowing gas is desired, the method will involve simply forcing the gas through a passage or enclosure and sampling the gas at a point within the gas stream, or using a heated tube.

[0048] Fig. Figure 12 shows further details of an embodiment of the connector 511 (shown in Fig.5) according to the present invention, wherein the fitting 511 is used as the attachment point of the tube 522 and the housing 510. The fitting 511 comprises the tube 522 and an outer tube 1210 welded or brazed to the exterior of the tube 522. The lower portion of the outer tube 1210 includes a flare 1212. In the illustrated embodiment of the flare 1212, the tube 1210 extends outward and downward before being bent back upon itself, thereby forming a double or double-layer flare. Other embodiments are possible, for example, a simple outward and downward extension (single flare) or a further bend back (triple flare).

[0049] A boss 1214 is welded or otherwise securely attached to the housing 510, and a nut 1216 is disposed around the outer tube 1210. To secure the attachment point, the nut 1216 is threaded downwardly into the boss 1214, the nut 1216 and boss 1214 having suitable threads for this purpose, and onto the double flare 1212, thereby compressing the flare 1212 and preventing gases from escaping from within the housing 510 through the fitting 511. The underside of the nut 1216a and the boss portion 1214a are angled for close engagement with the flare 1212.

[0050] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore indicated by the appended claims rather than by the foregoing description. All changes which come within the spirit and range of equivalence of the claims are therefore intended to be embraced within their scope.

Claims

[1] A static pressure measuring device, the device comprising: a housing (510) defining a passage (111) for the flow of gases; a static pressure tube (522) having an opening (522a), the static pressure tube (522) being attached to a side of the housing (510) at a connection point and extending into the passage (111) such that the opening (522a) is disposed within the flow of gases; a connecting part (511) arranged at the connection point, wherein: the connecting part (511) comprises an outer tube (1210) fixed to the exterior of the static pressure tube (522), the outer tube (1210) has a flange (1212) arranged on the lower portion of the outer tube (1210), the connector (511) further comprises a boss (1214) attached to the housing (510) for receiving the static pressure tube (522) and the outer tube (1210) and a nut (1216) arranged around the outer tube (1210) and configured to compress the flange (1212) against the boss (1214); and the flow of gases around the static pressure tube (522) increases the temperature of the static pressure tube (522). [2] The apparatus of claim 1, wherein the opening (522a) is located at least 7.62 cm (3 inches) from the connection point as measured along the static pressure tube (522). [3] The device of claim 1, wherein the housing (510) is cylindrical and the static pressure tube (522) extends radially into the passage (111). [4] The apparatus of claim 1, wherein the gases are exhaust gases, and further comprising a particulate filter (514) disposed downstream of the static pressure pipe (522) and a static pressure measuring device disposed downstream of the particulate filter (514), the device and the static pressure pipe (522) cooperating to determine the static pressure drop across the particulate filter (514). [5] The apparatus of claim 4, further comprising a catalytic device (512) disposed upstream of the static pressure pipe (522), the catalytic device (512) being capable of regeneration, the regeneration of the catalytic device (512) increasing the temperature of the exhaust gases and the static pressure pipe (522) while eliminating particulate accumulations on the opening (522a). [6] The device of claim 1, wherein the crimp (1212) comprises a double crimp (1212). [7] Static exhaust pressure measuring system, the system comprising: an exhaust housing (510) configured to receive the flow of exhaust gases; an elongated static pressure measuring tube disposed at a connection point through a side of the housing (510), the measuring tube having first and second ends, the measuring tube extending into the interior of the housing (510) such that the first end is disposed within the interior of the housing (510); an opening (522a) arranged at the first end of the measuring tube, wherein the opening (522a) is designed to remove the exhaust gases, and wherein a substantial portion of the measuring tube is arranged between the opening (522a) and the housing (510); a static pressure sensor (926) operatively connected to the second end of the measuring tube, the sensor (926) being configured to sense the static pressure of the gases; and a connector (511) arranged at the connection point, the connector (511) comprising an outer tube (1210) fixed to the exterior of the measuring tube, the outer tube (1210) having a flange (1212) arranged on the lower portion of the outer tube (1210), the connector (511) further comprising a boss (1214) attached to the housing (510) for receiving the measuring tube and the outer tube (1210) and a nut (1216) arranged around the outer tube (1210), the nut (1216) being configured to compress the flange (1212) against the boss (1214). [8] The system of claim 7, further comprising a motor (1010) that produces the exhaust gas, the motor (1010) being operatively connected to the exhaust housing (510). [9] System according to claim 7, wherein the housing (510) is cylindrical and the measuring tube extends radially into the interior of the housing (510). [10] The system of claim 7, wherein the crimp (1212) comprises a double crimp (1212). [11] The system of claim 7, further comprising a catalytic device (512) disposed upstream of the measuring tube and a particulate filter (514) disposed downstream of the measuring tube. [12] The system of claim 11, further comprising a static pressure measuring device arranged on the housing (510) after the particulate filter (514), the static pressure measuring device being operatively connected to the static pressure sensor (926), the difference between the static pressure measured by the measuring tube and the static pressure measured by the measuring device indicating the pressure drop across the particulate filter (514). [13] The system of claim 11, further comprising a regeneration mechanism (1012) configured to regenerate the catalytic device (512), wherein the regeneration of the catalytic device (512) heats the exhaust gas and regenerates the orifice (522a).

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