Measuring and testing – Fluid pressure gauge – Mounting and connection
Patent
1994-06-02
1996-03-19
Chilcot, Richard
Measuring and testing
Fluid pressure gauge
Mounting and connection
G01L 700
Patent
active
054995396
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
The invention pertains to a connecting flange for pressure sensing elements with a separable connection by means of which the connecting flange and the pressure sensing element are connected in a positive fashion, and with connecting elements via which the pressure sensing element is connected physically with the medium, the pressure of which is to be measured.
Pressure sensing elements of this type which are connected physically as well as positively with the connecting flange serve for measuring the differential pressure, excess pressure, negative pressure as well as the flow of gases, vapors, and liquids; such pressure sensing elements may also be used to measure the level of a container hydrostatically.
According to the generally known state of the art as, for example, described in the applicant's prospectus cell which is arranged in the interior of a measuring cell housing, the annular measuring cell housing, and two identically shaped connecting flanges which are arranged in a mirror image to each other and clamp the measuring cell with the measuring cell housing between themselves in a positive fashion such that it is sealed by means of separable screw connections. The measuring cell is connected to an electronic circuit via electrical connecting lines. The electronic circuit is enclosed by a housing. In addition, the electronics housing is equipped with connecting elements in order to produce the electrical connection between the pressure sensing element and an energy supply and/or information processing center. However, it is also possible to equip the electronics housing with a display device in order to display the pressure directly.
Holes penetrate through the two connecting flanges in order to connect the measuring cell with the medium to be measured physically. The lines by means of which measuring space and hence the medium to be measured are connected physically with the pressure sensing element may be connected to these holes.
Pressure sensing elements of this type are frequently used for measuring the pressure of aggressive or corrosive media which may be present in a gaseous or a liquid state. In such instances, it is necessary and customary to manufacture the connecting flange from a material which is resistant to the aggressiveness or corrosiveness of the medium to be measured. However, the annular seals which are clamped between the ceramic measuring cell and the connecting flanges as well as between the measuring cell housing and the connecting flanges must also consist of a material which is resistant to the medium to be measured. Connecting flanges consisting of high-alloy, noncorrosive steels, e.g., X 6 CrNiMoTi 17122 1.4571, or highly corrosion-resistant Ni, Co, Cr, Mo, Fe alloys are particularly suitable for this purpose.
However, when using pressure sensing elements under particularly difficult conditions, e.g., in a chemical plant, there exists the necessity to measure media, the aggressiveness and/or corrosiveness of which lies far beyond the resistance of conventional flange materials used. These media may, for example, consist of copper or sodium chloride, mixtures of hydrochloric acid and nitric acid, or heated sulfuric acids. In order to prevent materials which are not resistant to the aggressiveness or corrosiveness from coming into contact with the medium to be measured; it was already suggested to manufacture the connecting flanges of a polymer plastic which is resistant to most acids or bases instead of a metallic material.
The intense heating of the medium to be measured which is associated with the processing sequence in such chemical plants results in the disadvantage that such plastic flanges, despite the fact that they are resistant to the medium to be measured, lose their stability due to the high temperatures. This may lead to leaks and thus dangerous spillage of the medium to be measured at the positive connection between the connecting flange and the measuring cell housing.
The invention, in contrast, is based on the objective of specifying a con
REFERENCES:
patent: 3618390 (1971-11-01), Frick
patent: 4993265 (1991-02-01), Koen et al.
patent: 5063784 (1991-11-01), Ridenour
patent: 5313839 (1994-05-01), Ridenour
"High-Pressure Transducer Package NASA Tech Brief", N.T.I.S. Tech Notes, Springfield, Va., Nov. 1987.
"Konstruktionskriterien Fur Druck-Und Differenzdruck-Messumformer", Von Dipl.-Ing. E. Freitage, May 1986, messen prufen automatisieren, pp. 257-261.
Glienke Horst
Maier Winfried
Chilcot Richard
Endress & Hauser GmbH & Co.
Felber Joseph L.
LandOfFree
Metallic connecting flange for ceramic pressure sensing elements does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Metallic connecting flange for ceramic pressure sensing elements, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Metallic connecting flange for ceramic pressure sensing elements will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1953301