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EP-4686919-B1 - FLOW MEASUREMENT SYSTEM

EP4686919B1EP 4686919 B1EP4686919 B1EP 4686919B1EP-4686919-B1

Inventors

  • Schröter, Gerry
  • Panicke, Marcel
  • Kallisch, Gerald

Dates

Publication Date
20260513
Application Date
20240802

Claims (14)

  1. A throughflow measurement system (11) for measuring a fluid throughflow in a fluid line, in particular in a high pressure line, said throughflow measurement system (11) comprising: a housing (13) which has a fluid channel (15) and which defines a channel axis (17) by means of the course of the fluid channel (15), at least one ultrasonic probe (21, 22) which can be fastened to the housing (13) and which has a radiation direction (27), wherein, for fastening the ultrasonic probe (21, 22) to the housing (13), a fastening stub (33) is provided that is welded to the outer wall (29) of the housing (13) and that has a receiver (36) for the ultrasonic probe (21, 22), wherein the radiation direction (27) of the ultrasonic probe (21, 22) extends obliquely to the channel axis (17) when the ultrasonic probe (21, 22) is arranged in the receiver (36), wherein the fastening stub (33) has a lateral surface (43) which revolves around a stub axis (45) extending at a right angle to the channel axis (17) and which extends, starting from a housing-side end region of the fastening stub (33), in the direction of the stub axis (45), wherein a peripheral weld seam (46) is formed in the transition region between the lateral surface (43) of the fastening stub (33) and the outer wall (29) of the housing (13), characterized in that at least one spacer (55) projects from the outer wall (29) of the housing (31) and contacts a boundary surface (58) of the fastening stub (33).
  2. A throughflow measurement system according to claim 1, wherein the lateral surface (43) has a circular cylindrical shape and defines a cylinder axis which extends in parallel with the stub axis (45) and preferably coincides therewith.
  3. A throughflow measurement system according to claim 1 or 2, wherein the fastening stub (33) has at least one contact surface (37), in particular a planar contact surface (37), for the ultrasonic probe (21, 22), said contact surface extending obliquely to the stub axis (45).
  4. A throughflow measurement system according to any one of the preceding claims, wherein the fastening stub (33) has a planar clamping tool engagement surface (47) which extends at a right angle to the stub axis (45).
  5. A throughflow measurement system according to any one of the preceding claims, wherein the ultrasonic probe (21, 22) has a longitudinal axis (39) coinciding with the radiation direction (27) and a signal transmission surface (41) extending at a right angle to the longitudinal axis (39).
  6. A throughflow measurement system according to any one of the preceding claims, wherein at least one positioning pin (53) projects from the outer wall (29) of the housing (13) and is received in a pin receiver (57) of the fastening stub (33).
  7. A throughflow measurement system according to any one of the preceding claims, wherein at least one passage hole (31), which is in alignment with the receiver (36), for ultrasonic signals of the ultrasonic probe (21, 22) is formed in the housing (13).
  8. A throughflow measurement system according to any one of the preceding claims, wherein the throughflow measurement system (11) has at least one further ultrasonic probe (21, 22) which can be fastened to the housing (13), wherein a measurement path (25) extending obliquely to the channel axis (17) is formed between the two ultrasonic probes (21, 22) fastened to the housing (13).
  9. A throughflow measurement system according to any one of the preceding claims, wherein the housing (13) is at least sectionally tubular and is preferably provided with screw flanges at both ends.
  10. A method for fastening an ultrasonic probe (21, 22), which has a radiation direction (27), to a housing (13) which has a fluid channel (15) and which defines a channel axis (17) by means of the course of the fluid channel (15), comprising the steps: providing a fastening stub (33) which has a receiver (36) for the ultrasonic probe (21, 22) and a lateral surface (43) which revolves around a stub axis (45) and which extends, starting from an end region of the fastening stub (33), in the direction of the stub axis (45), positioning the fastening stub (33) relative to the housing (13) such that there is an air gap (61) between the end region and the outer wall (29) of the housing (13) and the stub axis (45) extends at a right angle to the channel axis (17), welding the fastening stub (33) to the outer wall (29) of the housing (13) while forming a peripheral weld seam (46) in the region of the air gap (61), and inserting the ultrasonic probe (21, 22) into the receiver (36) of the fastening stub (33) such that the radiation direction (27) of the ultrasonic probe (21, 22) extends obliquely to the stub axis (45), characterized in that the fastening stub (33) is moved towards the housing (13) during the positioning until at least one spacer (55) arranged at the outer wall (29) of the housing (13) abuts an end face (58) of the fastening stub (33).
  11. A method according to claim 10, wherein the spacer (55) is bolt-shaped and is inserted into a bolt receiver (51) of the housing (31).
  12. A method according to one of the claims 10 or 11, wherein the fastening stub (33) is moved towards the housing (13) during the positioning such that at least one positioning pin (53) arranged at the outer wall (29) of the housing (13) enters into a pin receiver (57) of the fastening stub (33), wherein the positioning pin (53) is preferably inserted into a pin receiver (51) of the housing (13).
  13. A method according to any one of the claims 10 to 12, wherein the fastening stub (33) is clamped against the housing (13) by means of a clamping tool during the welding, in particular wherein the clamping tool is brought into contact with a clamping tool engagement surface (47) of the fastening stub (33), said clamping tool engagement surface (47) preferably extending at a right angle to the stub axis (45).
  14. A method according to any one of the claims 10 to 13, wherein at least one passage hole (31) for ultrasonic signals is formed in the housing (13) before the positioning of the fastening stub (33) and the fastening stub (33) is positioned such that the passage hole (31) is aligned with the receiver (36) for the ultrasonic probe (21, 22).

Description

The invention relates to a flow measurement system for measuring a fluid flow in a fluid line, in particular in a high-pressure line, comprising: a housing having a fluid channel and defining a channel axis by the course of the fluid channel, and at least one ultrasonic probe which can be attached to the housing and which has a direction of emission, wherein a mounting stud is provided for attaching the ultrasonic probe to the housing, which is welded to the outer wall of the housing and which has a receptacle for the ultrasonic probe, wherein the direction of emission of the ultrasonic probe is inclined to the channel axis when the ultrasonic probe is arranged in the receptacle. In many areas of engineering, measurements must be taken on flowing fluids, i.e., gases or liquids. For example, flow velocities of fluids in pipelines can be determined using ultrasonic measurement technology based on the differential transit-time method. Based on the determined flow velocity and the known cross-sectional area of the pipeline, the volumetric flow rate of the fluid flowing through the pipeline can be calculated. Such volumetric flow measuring devices are frequently used in the form of meters to determine the delivery and/or consumption quantities of gases or liquids. Due to the oblique orientation of the radiation direction relative to the channel axis, a measurement section with a component in or against the flow direction is obtained, which is important for determining the axial flow velocity. However, the oblique orientation of the ultrasound probe is problematic. regarding the attachment to the housing, especially if it needs to be able to withstand high pressure. For example, a cylindrical mounting bracket can be welded to the housing at an angle to the channel axis, and the ultrasound probe can be aligned with the mounting bracket, i.e., positioned longitudinally within the mounting bracket. Such an arrangement is used, for example, in the CN 212082488 U1 revealed. However, due to the angled positioning of the mounting stud, this is associated with the risk of an uneven weld seam and undesirable distortion, which in many cases necessitates extensive rework. Nozzles angled to the channel axis can also be produced by forming or casting. However, this also involves considerable manufacturing effort. In high-pressure applications, the wall thickness of the housing is typically so great that forming techniques are not feasible anyway. To avoid misalignment of the mounting nozzle with the canal axis, a bent ultrasound probe could also be used; that is, an ultrasound probe with a bend so that the radiation direction is oblique to the probe axis. However, such probes are relatively expensive. Furthermore, positioning them with the required accuracy is difficult. The CN 2 658 719 Y Disclosure reveals a flow measurement system comprising an ultrasonic probe and a valve inserted between the probe and the duct housing. A section of pipe connected to the valve is attached to the duct housing by means of a mounting component. In the US 5 396 814 A A flow meter is disclosed, comprising two ultrasonic units which are attached to the associated pipe by means of respective brackets. The brackets are welded to the pipe. The CN 212 082 485 U Disclosing a flow measurement system with two ultrasonic probes arranged in respective receptacles of a mounting component. It is an object of the invention to provide a flow measurement system of the aforementioned type which ensures an exact and stable positioning of the ultrasound probe using simple means and preferably without mechanical post-processing. The problem is solved by a flow measurement system with the features of claim 1. According to the invention, the mounting stub has a cylindrical surface that surrounds a stub axis running perpendicular to the channel axis and extends from a housing-side end region of the mounting stub in the direction of the stub axis, wherein a circumferential weld seam is formed in the transition area between the cylindrical surface of the mounting stub and the outer wall of the housing. Thus, at least the part of the mounting sleeve facing the housing can be aligned perpendicular to the channel axis, which facilitates the welding process and, in particular, enables a comparatively uniform weld geometry, especially a uniform weld gap and a uniform weld seam, in contrast to a mounting sleeve welded at an angle to the housing. Distortion of the mounting sleeve during cooling is minimized. It has been found that, even with a flow measurement system according to the invention, particularly precise positioning of the The ultrasound probe is ensured if the mounting stud is welded to the housing automatically and without post-processing. If the housing has a round cross-section, the transition area between the outer surface of the mounting fitting and the housing's outer wall is curved, resulting in an axial variation in the circumferential weld seam relati