CN102507032A - COT thermocouple for cracking furnace - Google Patents
COT thermocouple for cracking furnace Download PDFInfo
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- CN102507032A CN102507032A CN2011103450228A CN201110345022A CN102507032A CN 102507032 A CN102507032 A CN 102507032A CN 2011103450228 A CN2011103450228 A CN 2011103450228A CN 201110345022 A CN201110345022 A CN 201110345022A CN 102507032 A CN102507032 A CN 102507032A
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Abstract
The invention provides a COT thermocouple for a cracking furnace. The COT thermocouple comprises a junction box, an upper protecting tube, a leak-preventing sealing device, a connecting flange, a lower protecting tube and a measurement end which are connected in turn, wherein the upper protecting tube, the leak-preventing sealing device, the lower protecting tube and the measurement end which are connected together form an inner cavity; an armored thermocouple is arranged in the inner cavity; the measurement end comprises a protective body and a measuring head which are connected into a whole; and the connected part of the measuring head and the protective body is provided with a temperature measuring groove. The COT thermocouple has high thermostability and high measurement accuracy.
Description
Technical field
The present invention relates to a kind of thermopair, particularly a kind of thermopair that is used to measure the rare device Control for Pyrolysis Furnace Area of second temperature.
Background technology
The temperature element of measuring the Control for Pyrolysis Furnace Area temperature need be set, with the process of monitoring cracking in ethane cracking furnace.For reaching this purpose, main mode is in the crack furnance radiation section furnace tube exit thermopair to be set, and measures the temperature in this exit, and the thermopair of employing is called as COT (Coil Outlet Temperature) thermopair.
The principle of work of thermopair is based on thermoelectric effect.Thermoelectric effect is meant that conductor (in thermopair, being called as thermocouple wire material or the thermode) two ends of two kinds of unlike materials are bonded into the loop, when the temperature at two abutments not simultaneously, in the loop, will produce electromotive force.The main element of thermopair is exactly a thermode, in order to protect thermode, need thermode be arranged in the protection tube, also is filled with insulating material in the protection tube, and this thermopair is called as armoured thermocouple (referring to Fig. 3).The end that thermopair touches measured medium is the working end, and the other end is a cold junction.Cold junction is connected with Displaying Meter or matching instrument, and Displaying Meter can be pointed out the thermoelectrical potential that thermopair produces.Thermopair is actually a kind of energy converter, and it is an electric energy with thermal power transfer, uses the thermoelectrical potential that is produced to characterize temperature.The thermoelectrical potential of thermopair is two thermode temperature funtions poor of thermopair working end, rather than the function of thermocouple cold junction and working end temperature difference.The size of the thermoelectrical potential that is produced, irrelevant when the material of thermode when being even, only relevant with the temperature difference at composition, working end and the cold junction two ends of thermode material with the length and the diameter of thermode.After the material of thermode was confirmed, the size of the thermoelectrical potential that produces was only relevant with the temperature difference of working end and cold junction.Further, certain if the temperature of cold junction keeps, thermoelectrical potential only is the single-valued function of working end temperature.
When pyrolysis furnace was in running order, its inner environment was: temperature is between 800 ℃-900 ℃, and the flow velocity of detected fluid medium is 138-175m/s.This shows that the COT thermopair should possess certain anti-safeguard measure of washing away, make the temperature that under harsh like this working environment, still can record fluid media (medium) accurately and efficiently.
Fig. 1 has shown existing a kind of COT thermopair, comprises the terminal box 1 that is linked in sequence, separated packoff 2, joint flange 3, following protection tube 4 and the measuring junction 5 of leaking.At a distance from leakage packoff 2, joint flange 3, following protection tube 4 with after measuring junction 5 is connected, formed the inner chamber 6 of a strip, armoured thermocouple is arranged in the inner chamber 6.The working end of said armoured thermocouple is positioned at measuring junction 5, and measuring junction 5 contacts with measured medium and measures; The cold junction of said armoured thermocouple is positioned at terminal box 1, is connected with cable.Because protection tube 4 can contact with the detected fluid medium with measuring junction 5 down, therefore, following protection tube 4 is all processed by the high-temperature alloy material with measuring junction 5, and improves the surface treatment of wearing quality.At a distance from leaking packoff 2 main effects be: the first, if measuring junction 5 breaks, when high temperature fluid upwards leaks along armoured thermocouple,, avoid high temperature fluid further to leak at a distance from leaking packoff 2 effective barrier fluid; The second, the high temperature of protection tube 4 and measuring junction 5 these sides under isolating avoids the temperature of cold junction in the butted line box to exert an influence.
An important indicator of COT thermopair is to keep precision, and this is embodied in three aspects: the sensitivity of COT thermopair, thermal stability (be under the duty the COT thermopair that makes as far as possible avoid measuring accuracy to descend in a long time) and serviceable life.
Summary of the invention
In order to improve the said precision and the serviceable life of COT thermopair, guarantee the obvious raising of ethylene furnace output and quality, the invention provides a kind of pyrolysis furnace COT thermopair.
Technical scheme of the present invention is following:
A kind of pyrolysis furnace COT thermopair comprises the terminal box that is linked in sequence, last protection tube, separated packoff, joint flange, following protection tube and the measuring junction of leaking; Said protection tube, separated leakage packoff, following protection tube and the measuring junction gone up that links together forms an inner chamber, in said inner chamber, is provided with armoured thermocouple, and said measuring junction comprises protection body and measuring head, and said measuring head and said protection body link into an integrated entity; Be provided with the thermometric groove at said measuring head and said protection body junction.
Make in the process of said armoured thermocouple, envionmental humidity is smaller or equal to 25%.
Said protection body is the combination of terrace with edge and pyramid, and the bottom surface of said terrace with edge is near said protection tube setting down, and the bottom surface of said pyramid is arranged on the upper bottom surface of said terrace with edge.
In the junction of said measuring head and said protection body, the width of said protection body is greater than the width of said measuring head; On the said protection body of said measuring head both sides, be respectively arranged with said thermometric groove.
Said thermometric groove separates said measuring head end with said protection body.
Projected area on the xsect of said cracking furnace pipe is a if said measuring junction extend into said cracking furnace pipe part; The projected area of said cracking furnace pipe inner chamber on said xsect is b; Then, the value of a/b is 1.2～2.5%.
The volume that said protection body extend into said cracking furnace pipe part is the 1200-6500 cubic millimeter.
Said joint flange is provided with suspension ring.
Said joint flange is provided with the ejection screw; Said pyrolysis furnace COT thermopair also comprises the ejection bolt with said ejection screw coupling; The distance that the said joint flange of said ejection bolt ejection moves is smaller or equal to 1 centimetre.
When said COT thermopair was assembled to said pyrolysis furnace, an end of said protection tube down and measuring junction slave unit connecting pipe stretched into, and the other end of said equipment connecting pipe is communicated with cracking furnace pipe; The outer wall of said protection tube down and the distance between the said equipment connecting pipe inwall are smaller or equal to 2 millimeters.
Said measuring junction is the 50-120 millimeter in the said length of protection tube axis direction down.
Said armoured thermocouple comprises two thermodes, and the spacing L of the parallel portion of said two thermodes is the 0.73-1.08 millimeter.
Minor increment M between the protection tube inwall of said thermode and said armoured thermocouple is the 0.73-1.08 millimeter; L equates with M.
The material of said terminal box is a spheroidal-graphite cast iron.
Said sealing and connecting device comprises seal connector, the packing seal web member that is linked in sequence; Said seal connector is connected with the said protection tube of going up, and said packing seal web member is connected with said joint flange; Be provided with cylindrical graphite grazing pad between said seal connector and the said packing seal web member; Be provided with the conical graphite sealing gasket between said packing seal web member and the said joint flange.
Technique effect of the present invention:
The thermometric groove is arranged between protection body and the measuring head;, fluid media (medium) forms turbulent flow when entering into around the measuring head; The thermometric groove has increased the thermometric area of measuring head on the one hand; The aggravation turbulent flow has prolonged the time that fluid media (medium) stops near measuring head on the other hand, and this all helps the accurate thermometric of measuring head.
In addition, influencing COT thermopair factors of accuracy has a lot, and people often pay close attention to the conventional factors such as purity like insulating material in the armoured thermocouple, and has ignored in making the armoured thermocouple process ambient humidity to the influence of final COT thermopair precision.In making the armoured thermocouple process, the employed insulating material of armoured thermocouple absorbs airborne moisture easily.The moisture distribution that insulating material absorbs is more even, and armoured thermocouple uses under low temperature condition, not adverse influence.When the temperature of measuring when armoured thermocouple surpassed 300 degrees centigrade, the moisture in the insulating material began to assemble, i.e. the distribution of moisture in insulating material begins to occur uneven trend, thereby moisture has a negative impact to the measuring accuracy of armoured thermocouple.Specifically influence is exactly to make the distortion of armoured thermocouple measurement result, and for example, measurement result is lower than actual temperature.Armoured thermocouple measurement result distortion meeting brings following consequence: during the measurement result of specific armoured thermocouple and be lower than actual temperature, the time and be higher than actual temperature; Because in actual use, all be that a plurality of thermopairs are measured same medium, the inconsistency of the measurement result of a plurality of thermopairs strengthens at this moment.These consequences all make the production of pyrolysis furnace to continue, and must change thermopair, cause cost to rise.The ambient humidity of technical scheme of the present invention when making armoured thermocouple limits, and effectively avoided airborne moisture in manufacture process, to penetrate into armoured thermocouple, improved the precision of armoured thermocouple.
Description of drawings
Fig. 1 is the external structure of existing COT thermopair.
Fig. 2 is the cut-open view of one section sheathed cable.
Fig. 3 is the cut-open view of armoured thermocouple thermometric end.
Fig. 4 is the elevational cross-sectional view of the on a rare occasion individual embodiment of COT thermoelectricity of the present invention.
Fig. 5 is a vertical view embodiment illustrated in fig. 4.
Fig. 6 is a upward view embodiment illustrated in fig. 4.
Fig. 7 is the stereographic map of thermometric end embodiment illustrated in fig. 4.
Fig. 8 is the elevational cross-sectional view of second embodiment of COT thermopair of the present invention.
Fig. 9 is a vertical view embodiment illustrated in fig. 8.
Figure 10 is a upward view embodiment illustrated in fig. 8.
Figure 11 is the stereographic map of thermometric end embodiment illustrated in fig. 8.
Figure 12 is the elevational cross-sectional view of the 3rd embodiment of COT thermopair of the present invention.
Figure 13 is a vertical view embodiment illustrated in fig. 12.
Figure 14 is a upward view embodiment illustrated in fig. 12.
Figure 15 is the stereographic map of thermometric end embodiment illustrated in fig. 12.
Figure 16 is installed to the wiring layout of pyrolysis furnace for COT thermopair of the present invention.
Identifier declaration is following among the figure:
1, terminal box; 2, at a distance from leaking packoff; 3, joint flange; 4, following protection tube; 5, measuring junction; 6, inner chamber;
7, protection tube; 8, inwall; 9, thermode; 10, insulating packing; 11, solder joint;
12, terminal box; 13, go up protection tube; 14, seal connector; 15, cylindrical graphite grazing pad; 16, packing seal web member; 17, conical graphite sealing gasket; 18, flange-interface spare; 19, suspension ring; 20, ejection bolt; 21, joint flange; 22, following protection tube; 23, armoured thermocouple; 24, measuring junction; 25, thermometric groove; 26, protection body; 27, measuring head;
28, terminal box; 29, go up protection tube; 30, seal connector; 31, cylindrical graphite grazing pad; 32, packing seal web member; 33, conical graphite sealing gasket; 34, flange-interface spare; 35, suspension ring; 36, ejection bolt; 37, joint flange; 38, following protection tube; 39, armoured thermocouple; 40, measuring junction; 41, thermometric groove; 42, protection body; 43, measuring head;
44, terminal box; 45, go up protection tube; 46, seal connector; 47, cylindrical graphite grazing pad; 48, packing seal web member; 49, conical graphite sealing gasket; 50, flange-interface spare; 51, suspension ring; 52, ejection bolt; 53, joint flange; 54, following protection tube; 55, armoured thermocouple; 56, measuring junction; 57, protection body; 58, measuring head;
59, joint flange; 60, nozzle flange; 61, following protection tube; 62, equipment connecting pipe; 63, measuring junction; 64, cracking furnace pipe.
Embodiment
Below technical scheme of the present invention is elaborated.
The manufacture process of armoured thermocouple in the COT thermopair of the present invention is described in conjunction with Fig. 2 and Fig. 3.In advance two rhizoid shape thermodes 9 are arranged in the protection tube 7; And in protection tube 7, fill insulating packing 10 (magnesia powder); To guarantee between two thermodes 9 parallel simultaneously; Formed sheathed cable after accomplishing above-mentioned steps, structure promptly shown in Figure 2 is the cable-like structure that extends to form of both direction up and down.The sheathed cable that manufacturing is good can coil into a volume as cable and be convenient to deposit.
Armoured thermocouple of the present invention is made with above-mentioned sheathed cable, and in following process for making, the relative humidity of environment (the environment here is meant the environment of carrying out following step process place, like workshop) is less than and equals 25%:
1, long one section of intercepting 1 meter (model according to armoured thermocouple is different, and length can be different) from the sheathed cable, and be drawn into straightened condition.This section abbreviated cable as before manufacturing armoured thermocouple.
2, at an end of said cable, with 9 welding of two thermodes, the welding back forms solder joint 11, and the diameter of solder joint 11 approximately is 1.6 times of diameter of thermode 9.
3, with protection tube 7 solder ups of solder joint 11 these ends, form the thermometric end of encirclement solder joint 11 as shown in Figure 3, should be full of insulating packing 10 in the thermometric end this moment.
4, the protection tube 7 of the cable other end is cut a bit of, remove insulating packing 10, expose a bit of of two thermodes 9.
5, will handle two thermodes 9 that expose through 4 and dry (can repeat oven dry) at 350-450 ℃ down.
6, will through 5 handle two thermodes 9 exposing the end separate with tetrafluoroethene.
7, the end of handled two thermodes 9 in 6 is entangled with the shutoff cover, the shutoff cover is passed in the end of two thermodes 9.
8, said shutoff cover and cable are clamped.
9, cable is provided with said this end encapsulating of shutoff cover.
The control of ambient humidity is very big to the influence of the thermal stability of final thermopair in the process of above-mentioned manufacturing armoured thermocouple, and table one has shown that the ambient humidity difference is to the influence of the thermal stability of final armoured thermocouple in the process of making armoured thermocouple.
Table one
COMPARISON OF CALCULATED RESULTS WITH EXPERIMENTAL DATA experiment to obtaining in the table one describes.
The first step, to testing as follows with the solder joint of the armoured thermocouple of making under the varying environment humidity: measure the thermopower value of solder joint under different temperatures, temperature is respectively 400 ℃, 600 ℃ and 800 ℃.
In second step, the armoured thermocouple of making under the varying environment humidity is made into the COT thermopair.These COT thermopairs are lasted 192 hours respectively wear out under 900 ℃ actual working environment, and then measure the thermopower value of thermode solder joint under different temperatures, temperature is respectively 400 ℃, 600 ℃ and 800 ℃.
In addition, the insulating resistance value of test armoured thermocouple under 500 ℃ and 900 ℃ of conditions respectively.The equipment of test armoured thermocouple insulating resistance value comprises: digital multimeter, 300～1200 ℃ of electric thermo-couple test furnaces of detected temperatures, low potential switch, 500V0-2000M Ω megohmmeter, freezing point calibration cell.The method of test armoured thermocouple insulating resistance value is summarized as follows:
At first, measuring junction and the standard platinum rhodium 10-platinum thermocouple with armoured thermocouple to be detected is bundled into circular a branch of with the high temperature silk.
Secondly, the above-mentioned thermopair of tying up bunchy is packed in the electric thermo-couple test furnace, the measuring junction of thermopair should be in assay furnace highest temperature district center, and standard couple is consistent with the assay furnace axial location.
The 3rd, the assay furnace fire door blocks up with insulating refractories around the thermopair bundle.
The 4th, be connected with copper conductor with the standard couple reference edge that armoured thermocouple to be detected is tied up, tie point inserts the freezing point calibration cell, and the copper conductor other end is connected with the low potential switch, and the low potential switch is connected with digital multimeter.
The 5th, assay furnace is warmed up to 500 ℃ or 900 ℃.Binding post of 500V0-2000M Ω megohmmeter is contacted the armoured thermocouple reference edge of tested detection, and another root binding post contacts tested thermopair shell, and the stable back of pointer value pointed is exactly an armoured thermocouple insulation values to be detected.
The experimental data that obtains through table one can obtain as drawing a conclusion:
1, the ambient humidity of manufacturing thermopair is low more, and through after the long duty, the thermopower of the solder joint of thermode trends towards increasing, and this helps improving the thermal stability of COT thermopair.Generally, through using for a long time, preferential oxidation can take place in the chromium in the positive pole of thermode, and thermoelectrical potential can slowly descend, and this variation is unfavorable for the thermal stability of COT thermopair.Through ambient humidity control, the thermopower of the solder joint of thermode trends towards increasing, and therefore helps improving the thermal stability of COT thermopair.
2, thermode is under the high temperature, because thermal expansion effects can make the insulating resistance value of armoured thermocouple reduce, insulation resistance value is low more, and is unfavorable more to the precision of thermopair, and insulation resistance value is minimum also will to keep 2M Ω.Visible from table one, the ambient humidity of making thermopair is low more, and the insulating resistance value of armoured thermocouple is high more.This conclusion can be applicable to make the COT thermopair that at high temperature has high insulating resistance value.
Can see from the data of table one that 3, the ambient humidity of preferably making thermopair is between 21% to 25%.
In order further to improve the thermal stability of COT thermopair, the spacing of two thermode parallel portion is between the 0.73-1.08 millimeter.For example, the spacing of two thermode parallel portion is 0.73 millimeter-0.79 millimeter when the diameter of thermode is 6 millimeters; The spacing of two thermode parallel portion is 0.97 millimeter-1.08 millimeters when the diameter of thermode is 8 millimeters.
Also be in order to improve the thermal stability of COT thermopair, the minor increment between the protection tube inwall of thermode and said armoured thermocouple is the 0.73-1.08 millimeter.For example, when the diameter of thermode is 6 millimeters and the minor increment between the protection tube inwall of said armoured thermocouple be 0.73 millimeter-0.79 millimeter; When the diameter of thermode is 8 millimeters and the minor increment between the protection tube inwall of said armoured thermocouple be 0.97 millimeter-1.08 millimeters.More excellent mode be the spacing and the thermode that make two thermode parallel portion with the protection tube inwall of said armoured thermocouple between distance equate.
Fig. 4 to Fig. 7 has shown first embodiment of COT thermopair of the present invention, comprises the terminal box 12 that is linked in sequence, last protection tube 13, separated packoff, joint flange 21, following protection tube 22 and the measuring junction 24 of leaking.Wherein, Comprise at a distance from leaking packoff: the seal connector 14 and the packing seal web member 16 that are linked in sequence; The upper end of seal connector 14 is connected with the lower end of last protection tube 13; The lower end of packing seal web member 16 is connected with joint flange 21 through flange-interface spare 18, is provided with cylindrical graphite grazing pad 15 between seal connector 14 and the packing seal web member 16, is provided with conical graphite sealing gasket 17 between packing seal web member 16 and the flange-interface spare 18.The sealing gasket of graphite material has the strong characteristics of plasticity; After armoured thermocouple 23 passes seal connector 14, cylindrical graphite grazing pad 15, packing seal web member 16 and conical graphite sealing gasket 17 and is seated; After dismounting armoured thermocouple 23 also assembles once more; At a distance from leaking the pressure that packoff still can bear 10Mpa, reduced replacement cost.Cylindrical graphite grazing pad 15 with conical graphite sealing gasket 17 manufacture processes is: through chemical treatment, high temperature expands and is rolled into graphite paper, and the graphite paper height is pressed into sealing gasket with the high-carbon scale graphite.The thickness of graphite paper be 0.2mm to 0.4mm, the end face plane of the sealing gasket made of the graphite paper of thickness is smooth like this, periphery is smooth, vestibule inner wall smooth, size are even, with armoured thermocouple 23 assembling back good seal performance, the finished product sealing gasket is non-friable.Cylindrical graphite grazing pad 15 can tolerate 800 ℃ high temperature with conical graphite sealing gasket 17, at 600 ℃ of pressure that still can bear 5Mpa.This makes the security of COT thermopair of the present invention improve greatly, for example when the unstable superhigh temperature of start operation control is more than 1000 ℃, and following protection tube 22 softening gas leakage, this can effectively be avoided the generation of leaking after leaking double seal.The right alignment of seal connector 14, cylindrical graphite grazing pad 15, packing seal web member 16 and conical graphite sealing gasket 17 can make at a distance from the sealing property of leaking packoff more excellent smaller or equal to 0.05 millimeter.After seal connector 14, cylindrical graphite grazing pad 15, packing seal web member 16 and conical graphite sealing gasket 17 assemble; Distance between seal connector 14 and the packing seal web member 16 is greater than and equals 5 millimeters; Distance between packing seal web member 16 and the flange-interface spare 18 is less than and equals 2 millimeters, and the taper number of degrees of conical graphite sealing gasket 17 and the flange-interface spare 18 inner conical number of degrees differ 2.5 °.
The last protection tube 13 that links together, separated packoff, joint flange 21, following protection tube 22 and the measuring junction 24 of leaking form a strip inner chamber, at said inner chamber armoured thermocouple 23 are set.The material of terminal box 12 is a spheroidal-graphite cast iron, and concrete model is QT450-10.Ductile cast iron material has good plasticity and toughness, and heat-proof quality is good, and pyrolysis furnace site environment temperature is high, will avoid receiving the interference of external high temperature in the terminal box 12, so the good ductile cast iron material of heat-proof quality is to select preferably.Armoured thermocouple 23 is made under smaller or equal to 25% condition at envionmental humidity, has good thermal stability.
From Fig. 4 and Fig. 5, can see, on joint flange 16, be uniformly distributed with 2 suspension ring 19 and 4 ejection screws.In 4 ejection screws, screwed in ejection bolt 20.After the COT thermopair is through long-time the use, can coking on the outer wall of following protection tube 22, the COT thermopair is bonded at is difficult on the equipment connecting pipe take out.Suspension ring 19 provide the force application part that lifts the COT thermopair, are convenient to the COT thermopair that is bonded on the equipment connecting pipe is pulled out.Lift the COT thermopair equally for ease; Be provided with the ejection screw, the ejection screw runs through joint flange 21, ejection screw and the disconnected screw of using; The equipment of corresponding ejection screw connects on the mouth of pipe ring flange does not have through hole; When lifting the COT thermopair on the needs slave unit connecting pipe, with 20 rotations of ejection bolt, ejection bolt 20 connects mouth of pipe ring flange to equipment and advances up to pushing up equipment connection mouth of pipe ring flange.Be further rotated ejection bolt 20, can make ejection bolt 20 as lifting jack with lifting on the COT thermopair slave unit connecting pipe.When coking is relatively more serious; The simple ejection bolt 20 that uses can't be lifting on the COT thermopair slave unit connecting pipe; Be further rotated ejection bolt 20 and then mobile joint flange 21 this moment again, can cause equipment to connect mouth of pipe ring flange and damage, even also can cause down protection tube 22 to damage.For this reason, limit distance that ejection bolt 20 ejection joint flanges 21 move smaller or equal to 1 centimetre, preferred 0.5 centimetre.The distance that ejection bolt 20 ejection joint flanges 21 move can effectively be become flexible coking place in this scope, be aided with suspension ring 19 again and lift joint flange 21, has avoided the generation of above-mentioned damage.
From Fig. 4, Fig. 6 and Fig. 7, can see the structure of measuring junction 24.Measuring junction 24 is to process with solid blank, and an end of measuring junction 24 is the ends that are connected with following protection tube 22, is a disk, and the diameter of this disk is identical with the external diameter of following protection tube 22, and is connected with following protection tube 22.From said disk boring, this hole is used to hold the thermometric end of armoured thermocouple 23.The other end at measuring junction 24, be processed into two parts---protection body 26 and measuring head 27.Protection body 26 is one-body molded with measuring head 27, and the external dimensions of protection body 26 and volume are greater than the external dimensions and the volume of measuring head 27.Protection body 26 is the combination of a terrace with edge and a pyramid from the appearance, and the bottom surface of terrace with edge is near said protection tube setting down, and promptly the bottom surface of terrace with edge is arranged on the said disk, and the bottom surface of said pyramid is arranged on the upper bottom surface of said terrace with edge.Certainly, protection body 26 itself is as a whole, and above-mentioned terrace with edge and the pyramid of utilizing describes the shape of protection body 26, only in order to express easily, and do not mean that protection body 26 is divided into terrace with edge and pyramid two parts.For the ease of understanding, provide the notion of pyramid and terrace with edge: if a polyhedral face is a polygon, all the other each faces are triangles that a public vertex is arranged, and this polyhedron is called pyramid so; The bottom surface of pyramid and be parallel to the part between a cross section of this bottom surface is called terrace with edge.
Be the hole that holds the thermometric end of armoured thermocouple 23 in the measuring head 27, the thermometric end of 27 pairs of armoured thermocouples 23 of measuring head forms protection.As shown in the figure, the volume of measuring head 27 is less, and promptly the thermometric end of armoured thermocouple (with reference to the thermometric end that comprises solder joint 11 shown in Figure 3) external protection is thin, and the thermometric end that is beneficial to armoured thermocouple 23 can reach in time to be responded to the temperature variation of outside.Protection body 26 with the width of measuring head 27 junctions width greater than measuring head 27, stop the impact of fluid media (medium) to measuring head 27.Protection body 26 has a plurality of anti-impact brush finish in measuring head 27 these sides dorsad, and the antiscour mask has higher intensity.Be provided with thermometric groove 25 in protection body 26 and measuring head 27 junctions.Thermometric groove 25 is arranged on the protection body 26, is positioned at the both sides of measuring head 27, the groove that thermometric groove 25 is left for oblique temperature measuring head direction.The effect of thermometric groove 25 is: form turbulent flow in the time of around fluid media (medium) enters into measuring head 27; Thermometric groove 25 has increased the thermometric area of measuring head 27 on the one hand; Aggravation is turbulent on the other hand; Prolonged near the time that fluid media (medium) stops measuring head 27, this all helps measuring head 27 accurate thermometrics.
The material of following protection tube 22 is the chrome-nickel alloy steel, and wherein chromium content is 20～33%, and nickel content is 30～42%, for example, and Incoloy800H, Incoloy800, XH45M.The compound requirement of protection tube 22 down of the intensity of this material, cost is cheap relatively simultaneously.
Fig. 8 to Figure 11 has shown another embodiment of COT thermopair of the present invention.Fig. 8 is identical to embodiment illustrated in fig. 11 and Fig. 4 effect of following structure of the same name in embodiment illustrated in fig. 7: terminal box 28, at a distance from leaking packoff, suspension ring 35, ejection bolt 36, joint flange 37, following protection tube 38, armoured thermocouple 39.Wherein, seal connector 30, cylindrical graphite grazing pad 31, packing seal web member 32 and conical graphite sealing gasket 33 orders link to each other, and have constituted said at a distance from leaking packoff.Fig. 8 is measuring junction 40 with Fig. 4 to difference embodiment illustrated in fig. 7 to embodiment illustrated in fig. 11, and the volume of the volume ratio protection body 26 of the protection body 42 of measuring junction 40 is smaller, the groove of thermometric groove 41 between protection body 42 and measuring head 43, directly leaving.Thermometric groove 41 is separated protection body 42 and measuring head 43.Figure 11 has shown the spatial structure of measuring junction 40.This set of thermometric groove 41 has following benefit: protection body 42 still is that one is connected with measuring head 43 basically, and when fluid media (medium) impacted, the intensity of measuring head 43 was still higher; Thermometric groove 41 makes the end of measuring head 43 outstanding, and the end is the main position of thermometric, and the contact area that has increased with fluid media (medium) is given prominence in the end, has improved temperature measurement accuracy.
Figure 12 to Figure 15 has shown the 3rd embodiment of COT thermopair of the present invention.Figure 12 is identical to embodiment illustrated in fig. 15 and Fig. 4 effect of following structure of the same name in embodiment illustrated in fig. 7: terminal box 44, at a distance from leaking packoff, suspension ring 51, ejection bolt 52, joint flange 53, following protection tube 54, armoured thermocouple 55.Wherein, seal connector 46, cylindrical graphite grazing pad 47, packing seal web member 48 and conical graphite sealing gasket 49 orders link to each other, and have constituted said at a distance from leaking packoff.Figure 12 is measuring junction 56 to embodiment illustrated in fig. 15 and Fig. 4 to difference embodiment illustrated in fig. 7.Measuring junction 56 comprises protection body 57 and measuring head 58, and protection body 57 separates setting with measuring head 58, protection body 57 be shaped as semisphere.Figure 15 has shown the spatial structure of measuring junction 56.Protection body 57 hemispheric shapes mean that anti-impact brush finish (being that protection body receives the face that fluid media (medium) washes away) is hemisphere face.Because anti-impact brush finish flow direction best and fluid media (medium) is certain angle, therefore, the angle direction of anti-impact brush finish has certain limitation for the angle that the COT thermopair extend into cracking furnace pipe.And the anti-impact brush finish to be hemisphere face can avoid this restriction, variation to a certain degree takes place in the angle that the COT thermopair extend into cracking furnace pipe, hemisphere face can both keep best angular relationship with the flow direction of fluid media (medium).
Figure 16 has shown that COT thermopair of the present invention is installed to the state of pyrolysis furnace.From Figure 16, can see; The one end entering of the following protection tube 61 of COT thermopair and measuring junction 63 slave unit connecting pipes 62 also makes measuring junction 63 extend into cracking furnace pipe 64; The joint flange 59 of COT thermopair is connected with the nozzle flange 60 of equipment connecting pipe 62; Distance between following protection tube 61 and equipment connecting pipe 62 inwalls is smaller or equal to 2 millimeters; This is apart from the probability that has reduced coking between time protection tube 61 and equipment connecting pipe 62 inwalls, and avoiding distance excessive simultaneously is the fluid media (medium) crossfire that makes progress, and this can make the accuracy of COT thermocouple temperature measurement reduce.
Measuring junction 63 extend into how much need taking all factors into consideration of cracking furnace pipe 64: measuring junction 63 stretches into excessive, and measuring junction 63 can stop the media flow in the cracking furnace pipe 64, and then has reduced the output and the quality of the product of pyrolysis furnace; Measuring junction 63 stretches into too small, and then measuring head is insufficient with contacting of fluid media (medium), accurately thermometric.For this reason; The present invention carries out like delimit the amount of stretching into of measuring junction 63: suppose that it is a at the area of the last projection of xsect (being the plane of vertical cracking furnace pipe axis) of cracking furnace pipe 64 that measuring junction 63 extend into cracking furnace pipe 64 parts; The area of cracking furnace pipe 64 inner chambers projection on this xsect is b; Then, the value of a/b is that 1.2～2.5% o'clock measuring junction 63 thermometrics are accurate, and is minimum to the output and the quality adverse effect of the product of pyrolysis furnace simultaneously.The volume that the protection body of measuring junction 63 extend into the part of cracking furnace pipe 64 is the 1200-6500 cubic millimeter.The volume that protection body is extend into the part of cracking furnace pipe 64 limits following meaning: it is too small that protection body stretches into the volume of cracking furnace pipe 64, is unfavorable for the measuring head of measuring junction 63 is formed effective protection; If it is excessive that protection body stretches into the volume of cracking furnace pipe 64, then fluid medium forms and stops, directly causes output to reduce.
Measuring junction 63 is preferably the 50-120 millimeter in the length of the axis direction of following protection tube 61.Because measuring junction 63 is to be welded to down on the protection tube 61, near the intensity the weld seam is lower, and under the effect of cracking furnace pipe 64 inner fluid media, this length is equivalent to arm of force length, if long, near weld seam, forms cracking easily; If this length is too short, fluid media (medium) can form directly following protection tube 61 and impact, and the intensity of protection tube 61 is lower down, the serviceable life that can reduce the COT thermopair.
It should be noted that the above is merely preferred embodiment of the present invention, be not so limit scope of patent protection of the present invention that the present invention can also adopt equivalent technologies to replace.So the equivalence that all utilizations instructions of the present invention and diagramatic content are done changes, or directly or indirectly apply to other correlative technology fields and all in like manner all be contained in the scope that the present invention contains.
Claims (15)
1. a pyrolysis furnace COT thermopair comprises the terminal box that is linked in sequence, last protection tube, separated packoff, joint flange, following protection tube and the measuring junction of leaking; Said protection tube, separated leakage packoff, following protection tube and the measuring junction gone up that links together forms an inner chamber; In said inner chamber, be provided with armoured thermocouple; It is characterized in that: said measuring junction comprises protection body and measuring head, and said measuring head and said protection body link into an integrated entity; Be provided with the thermometric groove at said measuring head and said protection body junction.
2. according to the said pyrolysis furnace COT of claim 1 thermopair, it is characterized in that: make in the process of said armoured thermocouple, envionmental humidity is smaller or equal to 25%.
3. according to claim 1 or 2 said pyrolysis furnace COT thermopairs; It is characterized in that: said protection body is the combination of terrace with edge and pyramid; The bottom surface of said terrace with edge is near said protection tube setting down, and the bottom surface of said pyramid is arranged on the upper bottom surface of said terrace with edge.
4. according to the said pyrolysis furnace COT of claim 3 thermopair, it is characterized in that: in the junction of said measuring head and said protection body, the width of said protection body is greater than the width of said measuring head; On the said protection body of said measuring head both sides, be respectively arranged with said thermometric groove.
5. according to the said pyrolysis furnace COT of claim 3 thermopair, it is characterized in that: said thermometric groove separates said measuring head end with said protection body.
6. according to the said pyrolysis furnace COT of claim 3 thermopair, it is characterized in that: establishing said measuring junction, to extend into the projected area of said cracking furnace pipe part on the xsect of said cracking furnace pipe be a; The projected area of said cracking furnace pipe inner chamber on said xsect is b; Then, the value of a/b is 1.2～2.5%.
7. according to the said pyrolysis furnace COT of claim 6 thermopair, it is characterized in that: the volume that said protection body extend into said cracking furnace pipe part is the 1200-6500 cubic millimeter.
8. according to the said pyrolysis furnace COT of claim 7 thermopair, it is characterized in that: said joint flange is provided with suspension ring.
9. said according to Claim 8 pyrolysis furnace COT thermopair, it is characterized in that: said joint flange is provided with the ejection screw; Said pyrolysis furnace COT thermopair also comprises the ejection bolt with said ejection screw coupling; The distance that the said joint flange of said ejection bolt ejection moves is smaller or equal to 1 centimetre.
10. according to the said pyrolysis furnace COT of claim 9 thermopair; It is characterized in that: when said COT thermopair is assembled to said pyrolysis furnace; One end of said protection tube down and measuring junction slave unit connecting pipe stretches into, and the other end of said equipment connecting pipe is communicated with cracking furnace pipe; The outer wall of said protection tube down and the distance between the said equipment connecting pipe inwall are smaller or equal to 2 millimeters.
11. according to the said pyrolysis furnace COT of claim 10 thermopair, it is characterized in that: said measuring junction is the 50-120 millimeter in the said length of protection tube axis direction down.
12. according to the said pyrolysis furnace COT of claim 11 thermopair, it is characterized in that: said armoured thermocouple comprises two thermodes, the spacing L of the parallel portion of said two thermodes is the 0.73-1.08 millimeter.
13. according to the said pyrolysis furnace COT of claim 12 thermopair, it is characterized in that: the minor increment M between the protection tube inwall of said thermode and said armoured thermocouple is the 0.73-1.08 millimeter; L equates with M.
14. according to the said pyrolysis furnace COT of claim 13 thermopair, it is characterized in that: the material of said terminal box is a spheroidal-graphite cast iron.
15. according to the said pyrolysis furnace COT of claim 14 thermopair, it is characterized in that: said sealing and connecting device comprises seal connector, the packing seal web member that is linked in sequence; Said seal connector is connected with the said protection tube of going up, and said packing seal web member is connected with said joint flange; Be provided with cylindrical graphite grazing pad between said seal connector and the said packing seal web member; Be provided with the conical graphite sealing gasket between said packing seal web member and the said joint flange.
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| CN201110345022.8A CN102507032B (en) | 2011-11-04 | 2011-11-04 | cracking furnace COT thermocouple |
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| CN201110345022.8A CN102507032B (en) | 2011-11-04 | 2011-11-04 | cracking furnace COT thermocouple |
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| CN102507032B CN102507032B (en) | 2016-03-30 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103278256A (en) * | 2013-03-22 | 2013-09-04 | 吴方立 | Cracking furnace cot thermocouple and mounting method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2932341Y (en) * | 2006-10-17 | 2007-08-08 | 乐清市伦特电子仪表有限公司 | Cracking oven COT thermocouple anti-scouring sleeve |
| JP2008096215A (en) * | 2006-10-10 | 2008-04-24 | Kawasaki Precision Machinery Ltd | Sheathed thermocouple for measuring temperature in high pressure domain, and its manufacturing method |
| CN201289405Y (en) * | 2008-12-30 | 2009-08-12 | 乐清市伦特仪表有限公司 | Special-purpose thermoelectric couple for measurement of degradation and coking resistance of pyrolysis furnace COT |
| CN201575871U (en) * | 2010-01-08 | 2010-09-08 | 浙江伦特机电有限公司 | COT thermocouple for tapered cracking furnace |
| CN201844889U (en) * | 2010-11-12 | 2011-05-25 | 浙江伦特机电有限公司 | Temperature sensor for high-temperature and low-temperature measurement of hearth |
| CN202403823U (en) * | 2011-11-04 | 2012-08-29 | 吴方立 | Cracking furnace COT thermocouple |
-
2011
- 2011-11-04 CN CN201110345022.8A patent/CN102507032B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008096215A (en) * | 2006-10-10 | 2008-04-24 | Kawasaki Precision Machinery Ltd | Sheathed thermocouple for measuring temperature in high pressure domain, and its manufacturing method |
| CN2932341Y (en) * | 2006-10-17 | 2007-08-08 | 乐清市伦特电子仪表有限公司 | Cracking oven COT thermocouple anti-scouring sleeve |
| CN201289405Y (en) * | 2008-12-30 | 2009-08-12 | 乐清市伦特仪表有限公司 | Special-purpose thermoelectric couple for measurement of degradation and coking resistance of pyrolysis furnace COT |
| CN201575871U (en) * | 2010-01-08 | 2010-09-08 | 浙江伦特机电有限公司 | COT thermocouple for tapered cracking furnace |
| CN201844889U (en) * | 2010-11-12 | 2011-05-25 | 浙江伦特机电有限公司 | Temperature sensor for high-temperature and low-temperature measurement of hearth |
| CN202403823U (en) * | 2011-11-04 | 2012-08-29 | 吴方立 | Cracking furnace COT thermocouple |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103278256A (en) * | 2013-03-22 | 2013-09-04 | 吴方立 | Cracking furnace cot thermocouple and mounting method thereof |
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| CN102507032B (en) | 2016-03-30 |
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Inventor after: Wu Jiate Inventor after: Wu Fangli Inventor after: Chen Jing Inventor after: Wang Yuhua Inventor before: Wu Jiate Inventor before: Wu Fangli Inventor before: Chen Jing Inventor before: Huang Man Inventor before: Wang Yuhua |
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