Vortex shedding flowmeter probe structure adopting novel packaging process

Abstract

The utility model relates to the technical field of vortex shedding flowmeters, in particular to a vortex shedding flowmeter probe structure adopting a novel packaging technology, which comprises a probe shell, a combination body used for outputting signals is fixedly connected in the probe shell, and the upper side of the probe shell is fixedly connected with a first packaging layer shell. A glass powder sintering packaging layer is arranged in the first packaging layer shell; the upper side of the first packaging layer shell is fixedly connected with a second packaging layer shell, a glue packaging layer is arranged in the second packaging layer shell, and the top of the second packaging layer shell is fixedly connected with high-performance bonding sealing silicon rubber. As the temperature required by sintering of the glass powder is far higher than the use temperature allowed by steam measurement of the vortex shedding flowmeter, the glass powder does not crack when encountering slow cold and hot changes, and the phenomenon that a probe cannot perform measurement due to moisture invasion caused by cracking of a packaging layer and the like is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of vortex flowmeters, and more specifically to a vortex flowmeter probe structure adopting a novel packaging process. Background Art

[0002] In the metallurgical, pharmaceutical, chemical, air separation and other industries, vortex flowmeters are widely used to measure steam flow. Since steam has high temperature, good thermal conductivity and strong penetration, the vortex probe used to measure steam flow needs to have good heat resistance. In addition, since the steam pipeline may be stopped for repair during operation, the pipeline temperature drops, and the temperature of the probe also drops. Therefore, the packaging part of the probe must be able to withstand the hot and cold changes in the probe temperature, as well as the possible cracking and other adverse reactions. Moreover, due to the high temperature characteristics of steam, the temperature around the running pipeline is also higher than the outdoor temperature, the water vapor is abnormally active, the water content in the air is high, and the humidity is heavy, which is more corrosive to the vortex probe. Therefore, the packaging process used by the vortex probe to cope with steam conditions is very important.

[0003] In order to achieve the above application requirements, the conventional solutions of domestic vortex flowmeter manufacturers are as follows:

[0004] 1) The vortex probe uses high temperature resistant crystal and is encapsulated with high temperature resistant glue.

[0005] 2) Add an additional sealing layer to the outside of the probe to prevent moisture from entering and contacting the surface of the probe packaging part.

[0006] This approach does meet the needs of industry users, but it also has the following limitations:

[0007] 1) Since the probe shell is made of stainless steel with strong thermal conductivity, and the glue encapsulation layer is close to the liquid contact part of the probe, the glue encapsulation layer is prone to cracking during the alternating hot and cold cycles of the probe, causing moisture in the external environment to enter the probe, making the probe internally conductive and unable to be used for measurement;

[0008] 2) Since the steam temperature measured by the vortex flowmeter can reach 350 degrees, asbestos gaskets are often used as the additional sealing layer on the outside of the probe. The gasket is affected by the assembly operation and the assembly ability of the employees during the assembly process, and there is a certain probability of leakage. When leakage occurs, the glue packaging layer cracks due to the alternating hot and cold, and the external moisture can easily enter the probe, making the probe internally conductive and unable to measure;

[0009] 3) Since manufacturers generally do not have the conditions for high-temperature steam testing, the reliability of the practice of encapsulating the probe with glue and adding an additional sealing layer on the outside of the probe cannot be verified before the instrument leaves the factory, which also increases the uncertainty during the use of the probe. Utility Model Content

[0010] In order to solve the above problems, the utility model provides a vortex flowmeter probe structure which is more stable and reliable and adopts a new packaging process.

[0011] In order to achieve the above-mentioned purpose, the utility model provides the following technical solutions, which mainly include:

[0012] A vortex flowmeter probe structure using a new packaging process includes a probe shell, a combination for outputting signals is fixedly connected inside the probe shell, a first packaging layer shell is fixedly connected to the upper side of the probe shell, a glass powder sintering packaging layer is provided inside the first packaging layer shell; a second packaging layer shell is fixedly connected to the upper side of the first packaging layer shell, a glue packaging layer is provided inside the second packaging layer shell, and a high-performance adhesive sealing silicone rubber is fixedly connected to the top of the second packaging layer shell, a first probe external lead and a second probe external lead are respectively passed through the glass powder sintering packaging layer and the glue packaging layer, and the first probe external lead and the second probe external lead are both electrically connected to the combination.

[0013] Preferably, the combination includes packaging glue, an external electrode, a first high-temperature crystal, a core rod, a second high-temperature crystal, a first probe steel wire lead and a second probe steel wire lead; the first high-temperature crystal and the second high-temperature crystal are fixedly connected to the core rod in sequence, the upper end of the core rod is fixedly connected to the external electrode, the outside of the above structure is wrapped with packaging glue and fixedly connected to the probe shell, and the whole is cylindrical, the second probe steel wire lead is fixedly connected to the external electrode, the first probe steel wire lead is fixedly connected to the core rod, the first probe steel wire lead is fixedly connected to the second probe external lead, and the second probe steel wire lead is fixedly connected to the first probe external lead.

[0014] Preferably, the steel wire lead of the first probe and the external lead of the second probe are fixedly connected by welding through a second capillary needle tube, and a second Teflon heat shrink tube is sheathed on the outer side of the second capillary needle tube.

[0015] Preferably, the steel wire lead of the second probe is fixedly connected to the external lead of the first probe by welding through a first capillary tube, and a first Teflon heat shrink tube is sheathed on the outer side of the first capillary tube.

[0016] It can be seen from the above technical solutions that compared with the prior art, the utility model adds a glass powder sintering sealing layer and retains a glue sealing layer. The glass powder melts under the action of high-frequency heating and perfectly wraps the probe lead, eliminating the intrusion of external moisture. Since the temperature required for sintering the glass powder is much higher than the allowable operating temperature of the vortex flowmeter for steam measurement, it will not crack when encountering slow changes in temperature, solving the problem of the probe being unable to measure due to moisture intrusion caused by cracking of the packaging layer. The glue sealing layer is retained to add double insurance to the glass powder sintering sealing layer, which further ensures the reliability of the probe. The new packaging process structure optimizes the packaging process requirements of the glue packaging layer, making it more reliable and stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of the utility model.

[0019] Figure 2 It is an enlarged view of X of the utility model.

[0020] Explanation of the accompanying drawings: 1-probe shell; 2-packaging glue; 3-external electrode; 4-first high-temperature crystal; 5-core rod; 6-second high-temperature crystal: 7-first probe steel wire lead; 8-first packaging layer shell; 9-glass powder sintering packaging layer; 10-second packaging layer shell; 11-glue packaging layer; 12-high-performance adhesive sealing silicone rubber; 13-second probe steel wire lead; 14-first probe external lead; 15-second probe external lead; 16-first Teflon heat shrink tube; 17-first capillary needle; 18-second Teflon heat shrink tube; 19-second capillary needle. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] Example

[0023] A vortex flowmeter probe structure using a new packaging process, such as Figure 1 As shown, it includes a probe shell 1, in which a combination for outputting signals is fixedly connected, a first packaging layer shell 8 is fixedly connected on the upper side of the probe shell 1, a glass powder sintering packaging layer 9 is arranged in the first packaging layer shell 8, a second packaging layer shell 10 is fixedly connected on the upper side of the first packaging layer shell 8, a glue packaging layer 11 is arranged in the second packaging layer shell 10, and a high-performance adhesive sealing silicone rubber 12 is fixedly connected to the top of the second packaging layer shell 10, which can play a buffering and protective role for the glue packaging layer 11, a first probe external lead 14 and a second probe external lead 15 are respectively passed through the glass powder sintering packaging layer 9 and the glue packaging layer 11, and the first probe external lead 14 and the second probe external lead 15 are both electrically connected to the combination; and the ends of the first probe steel wire lead 7 and the second probe steel wire lead 13 are both provided with a bending structure, which can ensure that the steel wire lead will not contact the probe shell 1 body, and effectively prevent the conduction between the steel wire lead and the probe shell 1 body.

[0024] The first packaging layer shell 8 of the glass powder sintered packaging layer 9 loaded in the present application is a polished tube. The outer surface of the traditional stainless steel tube needs to be solution treated before leaving the factory. The stainless steel tube after the solution treatment has high heat resistance. It takes more heating time to melt the internal glass powder during high-frequency heating. The use of polished tubes can effectively save operation time. According to actual measurements, the high-frequency heating operation time of the polished tube is only 1 / 3 of that of the solution treated stainless steel tube.

[0025] When high-frequency heating is used to melt and sinter the glass powder, the glass powder is in a liquefied and flowable state during the sintering process. The liquid glass in this state can be firmly adsorbed on the steel wire lead of the probe, isolating the moisture exchange inside and outside the packaging layer, and blocking external moisture from entering the probe through the packaging gap, thus eliminating the phenomenon of the probe being unable to measure due to internal conduction caused by moisture intrusion.

[0026] In this embodiment, the combination includes packaging clay 2, an external electrode 3, a first high-temperature crystal 4, a core rod 5, a second high-temperature crystal 6, a first probe steel wire lead 7 and a second probe steel wire lead 13; the first high-temperature crystal 4 and the second high-temperature crystal 6 are fixedly connected to the core rod 5 in sequence, and the upper end of the core rod 5 is fixedly connected to the external electrode 3. The outer side of the above structure is wrapped with packaging clay 2 and fixedly connected to the probe shell 1, and the whole is cylindrical. The second probe steel wire lead 13 is fixedly connected to the external electrode 3, the first probe steel wire lead 7 is fixedly connected to the core rod 5, the first probe steel wire lead 7 is fixedly connected to the second probe external lead 15, and the second probe steel wire lead 13 is fixedly connected to the first probe external lead 14.

[0027] The glue encapsulation layer 11 needs to ensure that the glue is encapsulated under a heating state. The glue encapsulated under the heating state has good fluidity, and the flowing glue can fill in various dead corners of the encapsulation layer to form a closed encapsulation layer.

[0028] The glue adopts a polymer composite structure, is resistant to high temperatures and corrosion, and performs well under alternating hot and cold conditions;

[0029] The double-layer packaging is beneficial to isolating internal and external moisture. The presence of the glue packaging layer 11 is beneficial to preventing external moisture from corroding the glass powder sintering packaging layer 9, so that the impedance of the probe steel wire lead at the glass powder sintering packaging layer 9 will not increase due to moisture corrosion, thereby affecting the measurement result.

[0030] At the same time, the glue encapsulation layer 11 encapsulates the steel wire lead inside the probe and the welding point of the external probe lead. The heat tracing process of the glue encapsulation makes the glue in a liquid state. The glue perfectly wraps the probe lead, so that the external moisture cannot enter the internal encapsulation layer and the internal crystal layer of the probe through the encapsulation gap, and thus cannot have an adverse effect on the measurement.

[0031] In this embodiment, if Figure 2 As shown, the first probe steel wire lead 7 and the second probe external lead 15 are fixedly connected by welding through a second capillary needle tube 19 , and a second Teflon heat shrink tube 18 is sheathed on the outer side of the second capillary needle tube 19 .

[0032] In this embodiment, if Figure 2 As shown, the second probe steel wire lead 13 and the first probe external lead 14 are fixedly connected by welding through a first capillary needle tube 17 , and a first Teflon heat shrink tube 16 is sheathed on the outside of the first capillary needle tube 17 .

[0033] The above-mentioned probe steel wire lead and probe external lead are welded through a capillary needle tube by resistance welding. The steel wire lead and the capillary needle tube, the external lead and the capillary needle tube are multi-point resistance welded respectively, which can effectively provide welding strength, increase service life, reduce operating requirements, and improve the yield rate.

[0034] In addition, the welding point between the probe steel wire lead and the probe external lead is isolated and protected by a Teflon sleeve. The Teflon sleeve is temperature-resistant to 300°C and can effectively isolate each steel wire lead to ensure that the leads are not connected to each other.

[0035] The specific implementation steps are as follows:

[0036] Coat the back of the first high temperature crystal 4 and the second high temperature crystal 6 with conductive glue, stick them on the core rod 5, and weld the first probe steel wire 7 to the core rod 5 by resistance welding;

[0037] Weld the second probe wire lead 13 to the middle of the outer electrode 3 by resistance welding;

[0038] Bend the middle part of the outer electrode 3, apply conductive glue, and stick it on the core rod 5;

[0039] The assembled body is tied and fixed with glass fiber rope, placed in an oven at 80°C, and taken out after 2 hours;

[0040] The dried assembly is wrapped with the encapsulating glue 2, kneaded into a cylindrical shape, and then placed in a 65°C oven and taken out after 1 hour;

[0041] Take out the dried assembly, bend the first probe steel wire 7 and the second probe steel wire 13 inward, put them into the probe shell 1, add a small amount of encapsulation glue 2 to fill and fix, put them into a 65°C oven, and take them out after 1 hour;

[0042] Laser welding the first packaging layer shell 8 to the probe shell 1

[0043] Lead-free glass powder is added into the first encapsulation layer shell 8 and sintered on a workbench to produce a glass powder sintered encapsulation layer 9. The sintering time is 23 seconds.

[0044] After the glass powder sintered packaging layer 9 is naturally cooled, the second probe steel wire lead 13 and the first probe external lead 14 are respectively inserted into the two ends of the first capillary needle tube 17 and inserted to the bottom, and resistance welding is adopted. After the welding is completed, the first probe external lead 14 is pulled to ensure reliable welding;

[0045] Insert the first probe wire lead 7 and the second probe external lead 15 into the two ends of the second capillary needle tube 19 and insert them to the bottom, and weld them by resistance welding. After welding, pull the second probe external lead 15 to ensure reliable welding;

[0046] Insert the first Teflon heat shrink tube 16 and the second Teflon heat shrink tube 18 into the two capillary needle welding points respectively;

[0047] Laser welding the second packaging layer shell 10 to the first packaging layer shell 8;

[0048] Add the prepared polymer glue into the second packaging layer shell 10, and heat it with a heat source, the temperature of which is between 80°C and 100°C, so that the glue flows and fills the entire second packaging layer shell 10, thereby completing the glue packaging layer 11;

[0049] When the glue encapsulation layer 11 is in a semi-dry state, a high-performance adhesive sealing silicone rubber 12 is coated on the top of the glue encapsulation layer 11 .

[0050] After passing the inspection, the production is completed and put into storage for use in subsequent probe assembly.

[0051] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0052] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A vortex flowmeter probe structure using a new packaging process, including a probe shell, characterized in that: A combination for outputting signals is fixedly connected inside the probe shell, a first packaging layer shell is fixedly connected on the upper side of the probe shell, a glass powder sintering packaging layer is provided inside the first packaging layer shell; a second packaging layer shell is fixedly connected on the upper side of the first packaging layer shell, a glue packaging layer is provided inside the second packaging layer shell, a high-performance adhesive sealing silicone rubber is fixedly connected to the top of the second packaging layer shell, a first probe external lead and a second probe external lead are respectively passed through the glass powder sintering packaging layer and the glue packaging layer, and the first probe external lead and the second probe external lead are both electrically connected to the combination.

2. The vortex flowmeter probe structure according to claim 1, characterized in that: The combination includes packaging glue, an external electrode, a first high-temperature crystal, a core rod, a second high-temperature crystal, a first probe steel wire lead and a second probe steel wire lead; the first high-temperature crystal and the second high-temperature crystal are fixedly connected to the core rod in sequence, the upper end of the core rod is fixedly connected to the external electrode, the outer side of the above structure is wrapped with packaging glue and fixedly connected to the probe shell, and the whole is cylindrical, the second probe steel wire lead is fixedly connected to the external electrode, the first probe steel wire lead is fixedly connected to the core rod, the first probe steel wire lead is fixedly connected to the second probe external lead, and the second probe steel wire lead is fixedly connected to the first probe external lead.

3. The vortex flowmeter probe structure according to claim 2, characterized in that: The first probe steel wire lead and the second probe external lead are fixedly connected by welding through a second capillary needle tube, and a second Teflon heat shrink tube is sleeved on the outer side of the second capillary needle tube.

4. The vortex flowmeter probe structure according to claim 2, characterized in that: The steel wire lead of the second probe is fixedly connected to the external lead of the first probe by welding through a first capillary needle tube, and a first Teflon heat shrink tube is sleeved on the outer side of the first capillary needle tube.

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