Method for Manufacturing a Measuring Tube

Abstract

A method for manufacturing a measuring tube, which serves for conveying a measured substance, which measuring tube comprises a pipeline having a lumen, into which lumen an immersion body protrudes. The immersion body is connected with a formed piece, and the formed piece is connected with the pipeline in such a manner that a vacancy in the wall of the pipeline is essentially measured substance tightly, for example, gas tightly and/or liquid tightly, sealed by the formed piece.

Claims

1-17. (canceled)

18. A method for manufacturing a measuring tube, which serves for conveying a measured substance, which measuring tube comprises a pipeline having a lumen, into which lumen an immersion body protrudes; the method comprising the steps of: providing a formed piece with the immersion body; connecting the immersion body with the formed piece; and sealingly connecting the formed piece with the pipeline in such a manner that a vacancy in the wall of the pipeline is essentially sealed tightly by the formed piece against the measured substance, for example, a gas and/or a liquid.

19. The method as claimed in claim 18, wherein: a piece of the tube wall, especially a tube wall section, is removed from the pipeline and serves as the formed piece.

20. The method as claimed in claim 18, wherein: the vacancy is formed by removing a piece of the wall of the pipeline.

21. The method as claimed in claim 18, wherein: the vacancy is provided especially window shaped or terminally in the pipeline.

22. The method as claimed in claim 19, wherein: the removed tube wall section is reconnected with the pipeline.

23. The method as claimed in claim 19, wherein: the formed piece, especially the removed tube wall section, has an essentially arc shaped cross section.

24. The method as claimed in claim 18, further comprising the step of: placing a sensor element in the immersion body.

25. The method as claimed in claim 24, wherein: there is used as the immersion body a tubular protective tube, which serves for accommodating the sensor element.

26. The method as claimed in claim 18, wherein: the immersion body is welded with the formed piece.

27. The method as claimed in claim 18, further comprising the step of: smoothing a weld seam between the immersion body and the formed piece, before the formed piece is connected with the pipeline.

28. The method as claimed in claim 18, wherein: the immersion body is connected, preferably welded, with the formed piece in such a manner that a radius between the immersion body and the formed piece satisfying hygiene regulations is formed.

29. The method as claimed in claim 18, wherein: the formed piece is removed from the tube wall by means of a laser- or plasma cutting method.

30. The method as claimed in claim 18, wherein: the formed piece is connected with the pipeline by means of a welding method.

31. The method as claimed in claim 18, wherein: a weld seam between the formed piece and the pipeline at the lumen of the measuring tube is smoothed, for example, by grinding and/or polishing the weld seam.

32. A measuring tube, which serves for conveying a measured substance, said measuring tube comprising a pipeline having a lumen, into which lumen an immersion body protrudes; said measuring tube produced by a method comprising the steps of: providing a formed piece with the immersion body; connecting the immersion body with the formed piece; and sealingly connecting the formed piece with the pipeline in such a manner that a vacancy in the wall of the pipeline is essentially sealed tightly by the formed piece against the measured substance, for example, a gas and/or a liquid.

33. A measuring tube as claimed in claim 32, wherein: said pipeline is a T-piece or an elbow.

34. A measuring system having a measuring tube as claimed in claim 32, wherein the immersion body includes a measuring transducer for determining temperature.

Description

[0034] The invention will now be explained in greater detail based on the appended drawing, the figures of which show as follows:

[0035] FIG. 1 a schematic representation of one form of embodiment of a measuring tube comprising a pipeline, a formed piece and an immersion body, and

[0036] FIG. 2 an exploded view of an additional form of embodiment of a measuring tube comprising a pipeline, a formed piece, an immersion body and a neck tube.

[0037] FIG. 1 shows a form of embodiment of a measuring tube M, which comprises a pipeline P, which serves for conveying, for example, a flowing, measured substance. Inserted in a vacancy V in the pipeline P is a formed piece F corresponding to the vacancy. The vacancy V is sealed by the formed piece F. Arranged centrally in the formed piece F in an opening O in the pipeline P is an immersion body I. The immersion body I is likewise embodied in the form of a tube, which has a base, which protrudes into the lumen of the pipeline P.

[0038] The immersion body I serves here for accommodating a measuring insert (not shown), which can be introduced into the immersion body I. Suitable (virtually) standardized measuring inserts are known, for example, for temperature measurement.

[0039] The measuring tube M includes a first, for example, welded, connection S2 between the formed piece F and the pipeline P. Furthermore, the measuring tube M includes a second, for example, welded, connection S1 between the formed piece F and the immersion body I.

[0040] The measuring tube M can be produced, in such case, for example, as described in the following. Cut out from a pipeline P, such as, for example, a round tube, is a formed piece F, so that an opening O is formed in the pipeline P, which connects the lumen of the pipeline P with the environment of the pipeline P. The formed piece F, respectively the vacancy V, has, in such case, preferably in cross section perpendicular to the longitudinal axis L, which serves as polar axis, a polar angle θ of greater than 45° . Preferably, the polar angle θ predetermined by the vacancy, respectively the formed piece, amounts to essentially 180° .

[0041] The proposed connection between the immersion body and the formed piece, respectively between the formed piece and the pipeline P, enables a hygienic welding of the components. The corresponding regulations prohibit a sharp edged transition between the components, since then the danger of material attachments is present. Rather, according to regulation, a radius, respectively a certain angle and/or a certain surface quality, must be present; compare, for example, Offenlegungsschrift DE 102012112579 A1.

[0042] Here, for example, a formed piece F can be removed from the pipeline P with the assistance of a 3D cutting machine, for example, by means of a laser- or plasma cutting method. The immersion body in the form of a tube wall section can be welded into this formed piece F. Because the formed piece F, when removed, is accessible from both sides, the weld seam S1 can be produced conforming to standard. In such case, for example, the radius of the transition between the immersion body and the formed piece can be polished.

[0043] Then, the formed piece F is welded back into the pipeline P. This welded seam S2 can now also be worked further from the inside, since the immersion body does not hinder the processing, respectively no longer must be processed. With suitable tools, thus the weld seam S2 can be ground and/or polished.

[0044] FIG. 2 shows a form of embodiment of the proposed invention in an exploded view. In a vacancy V of the pipeline, a formed piece F, in which an immersion body I, for example, a tubular immersion body I, has already been mounted, is connected with the pipeline P. The immersion body is, thus, first of all, placed in an opening O of the formed piece F and connected with the formed piece.

[0045] The immersion body I is, for example, tubularly embodied and includes a closed end, which serves to extend into the lumen of the pipeline. Furthermore, the immersion body I includes an open end lying opposite the closed end, into which a sensor element can be inserted.

[0046] The immersion body I is, in such case, introduced in such a manner into the opening that the edge of the open end of the immersion body is arranged flush with the surface of the formed piece. Alternatively, the immersion body I can, such as shown in FIG. 1, extend out on both sides of the formed piece F.

[0047] Preferably, the immersion body I protrudes in the installed state no more than half the tube diameter of the pipeline P into the lumen of the pipeline P.

[0048] From a round tube, which is straight or bent, and serves as pipeline P, a part of the wall, which serves as the formed piece, can be removed. Then, in this formed piece, a hole serving as opening O can be drilled and the immersion body inserted into this hole. Following this, the immersion body I can be welded with the formed piece F. The resulting weld seam can then be processed from both sides of the formed piece, i.e. the side facing the lumen of the pipeline in the installed state and the side facing the environment of the pipeline in the installed state. In such case, for example, a desired roughness of the formed piece and of the immersion body can be produced and/or a desired radius of the welded connection can be produced. Then, the formed piece can be welded back into the pipeline. Also, this weld seam can then be subsequently processed, since the welded-on immersion body does not hinder the processing.

[0049] Furthermore, a so-called neck tube N can be provided, which is likewise connected with the pipeline P and which is arranged in such a manner that the immersion body I is arranged within the neck tube N on the side of the pipeline P facing the environment. The neck tube can serve, for example, to accommodate connection lines to the sensor element or a measurement signal processing electronics

[0050] The proposed invention offers, thus, the advantage that a dead space free, measuring tube is created, which manages without a cross-section change of the pipeline. Furthermore, the welded seams can be processed in simple manner, in order to assure meeting of the requirements as regards application in plants, which must satisfy hygiene specifications.