An automatic distillation range measuring instrument and its calibration method

Abstract

This invention belongs to the field of distillation apparatus technology and discloses an automatic distillation range measuring instrument and its calibration method, including a housing, a distillation flask, and a tube cover. The left end of the housing has a working area A, and the right end has a working area B. A control box is fixedly installed on the top of the housing. A heating plate is fixedly connected inside the working area A. The invention simultaneously starts a first motor to drive a second pulley to rotate. This, in turn, drives the first pulley to rotate via a drive belt, causing the tube cover to rotate with the mounting end. The serpentine condenser then rotates, and small volumes of liquid adhering to the inner wall of the serpentine condenser, under centrifugal force, slowly slide along the inner wall and merge with other small volumes of liquid to form a larger volume of liquid. Simultaneously, propelled by gas, this liquid drips down the discharge pipe into the collection bottle, effectively cleaning the liquid inside the serpentine condenser and avoiding waste.

Description

Technical Field

[0001] This invention belongs to the field of distillation apparatus technology, specifically an automatic distillation range measuring instrument and its calibration method. Background Technology

[0002] A distillation apparatus, also known as a distillation device, is a technology that separates substances under vacuum conditions. It is widely used in the extraction of vitamins, active ingredients from traditional Chinese medicine, petrochemicals, and the food industry. It works by boiling the solution inside a distillation flask. The desired component is vaporized and condensed into a liquid by a condenser, dripping into a collection flask. However, existing automatic distillation range measuring instruments and their calibration methods suffer from this problem. During condensation, the liquid adheres to the inner wall of the condenser. As the volume of the liquid increases, its weight causes it to drip directly down the inner wall of the condenser for collection. However, after distillation, insufficient vapor enters the condenser, and the small volume of liquid adhering to the inner wall is too small to drip due to its own weight, resulting in the waste of some components. Furthermore, the entire process requires heating, and the flask containing the original solution needs nearly two hours, or even longer, to cool down after the experiment before subsequent cleaning and refilling can be performed. This long waiting time leads to delays and wasted time. Summary of the Invention

[0003] The purpose of this invention is to provide an automatic distillation range measuring instrument and its calibration method to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an automatic distillation range measuring instrument and its calibration method, comprising a housing, a distillation flask, and a tube cover. A working area A is provided at the left end of the housing, and a working area B is provided at the right end of the housing. A control box is fixedly installed on the top of the housing. A heating plate is fixedly connected inside the working area A, and a positioning hole is provided on the upper surface of the heating plate. A branch pipe is fixedly installed on the housing, and a connecting pipe is fixedly connected to the right side of the branch pipe. A gas guide pipe is fixedly installed on the connecting pipe, and a fixing block is fixedly connected inside the gas guide pipe. A fixing plate is provided at the bottom of the fixing block. The working area B... An inflation device is fixedly connected to the inner wall of the working area. An installation end is fixedly installed on the top of the tube cover. A first pulley is fixedly connected to the outer side of the upper end of the installation end. A drive belt is sleeved on the outside of the first pulley. Bearings are fixedly installed on the outer side of the lower end of the installation end and the outer side of the tube cover. A serpentine condenser tube is fixedly installed inside the tube cover. A support plate that is movably sleeved on the outside of the bearing is fixedly connected to the inner wall of the B working area. A first motor is fixedly connected to the inner wall of the B working area. A collection bottle located directly below the tube cover is placed inside the B working area. A threaded sleeve is fixedly installed at the bottom of the control box.

[0005] Preferably, a drain pipe is fixedly connected to the outside of the distillation flask, and a sealing plug is provided inside the drain pipe. A lifting platform is fixedly connected inside the A working area, a support plate is fixedly connected to the top of the lifting platform, and a refrigeration box is fixedly connected to the top of the support plate.

[0006] Preferably, the inflation device is externally fixedly connected to an air supply pipe, and an air inlet is provided at equal intervals along the outer side of the lower end of the air supply pipe.

[0007] Preferably, a flexible hose is fixedly connected to the outside of the branch pipe, the flexible hose is fixedly connected to the connecting pipe, a disc is fixedly installed on the outside of the connecting pipe, and a threaded rod that is movably connected to the disc is movably sleeved in the middle of the threaded sleeve.

[0008] Preferably, the bottom of the fixing block has equidistant holes along the annular ring, a spring is fixedly connected inside the holes, the middle of the fixing block has a through opening, and the top of the fixing plate has a rod fixedly connected to the spring along the annular ring.

[0009] Preferably, the mounting end has a frustum-shaped structure, a rubber pad is fixedly installed on the inner wall of the mounting end, a coolant inlet / outlet is fixedly connected to the outer side of the tube cover, and a discharge pipe is fixedly connected to the bottom of the tube cover.

[0010] Preferably, a second pulley is fixedly connected to the bottom of the first motor, the drive belt is sleeved on the outside of the second pulley, a temperature measuring device is fixedly connected to the top of the distillation flask, and a connecting end is fixedly installed on the outside of the distillation flask.

[0011] Preferably, an installation sleeve is fixedly installed on the outer side of the sealing plug, and threads are engraved on both the outer wall of the drain pipe and the inner wall of the installation sleeve.

[0012] Preferably, a first motor is fixedly installed on the top of the support plate, and an agitator plate located inside the refrigeration box is fixedly installed on the top of the first motor. A slide rail is provided on the inner wall of the A working area. Limiting sliders that are slidably connected inside the slide rails are fixedly installed on both sides of the refrigeration box. Side plates are fixedly connected to the top of the three sides of the refrigeration box.

[0013] A calibration method for an automatic distillation range meter includes the following steps:

[0014] A: Preparations

[0015] A1: Measure 100 mL of standard sample

[0016] Inject the standard sample into the distillation flask. Excess standard sample will flow out from the drain tube. Once the standard sample stops flowing out, seal the stopper. Then place the distillation flask into the positioning hole on the upper surface of the heating plate.

[0017] A2: Determine the location of the temperature measuring device

[0018] When the temperature measuring device uses a mercury thermometer, the thermometer bulb should be positioned on the center line, and the bottom of the mercury capillary tube should be flush with the bottom of the inner wall of the branch tube.

[0019] When a platinum resistance thermometer is used in the temperature measuring device, the upper ends of the two parallel platinum wires are flush with the bottom of the inner wall of the branch pipe.

[0020] A3: Check the instrument's sealing.

[0021] Check the sealing between the mouth of the distillation flask and the temperature measuring device, between the distillation flask and the branch pipe, and between the branch pipe and the connecting pipe;

[0022] B: Set the heating program for the control box according to the standard sample, heat the standard sample, distill at a rate of 45 mL / min, and automatically record the initial boiling point IBP, the temperature reading at 5% recovery volume, the temperature reading at 10% recovery volume, the temperature reading at each multiple of 10% recovery volume, the final boiling point FBP, and the measured atmospheric pressure; at the same time, record the maximum recovery volume Vmax and the corresponding temperature. After reaching the final boiling point, when the temperature is raised to the highest point according to the heating program, the instrument stops the heating program, and the entire distillation range test is completed.

[0023] C: After the distillation range test is completed, clean the remaining standard sample inside the serpentine condenser.

[0024] Rotate the threaded rod upwards to make it rise through the disc and drive the connecting pipe upwards without contacting the rubber pad. During the process, the gas guide pipe drives the fixed block upwards, and the gas supply pipe is directly inserted into the inlet and moves downwards against the fixed plate. Then the inlet is connected to the inside of the gas guide pipe. Start the gas filling device and introduce pure gas into the gas guide pipe through the gas supply pipe. The gas is then introduced into the serpentine condenser to remove residual standard samples. At the same time, start the first motor to make the tube cover rotate with the installation end. The serpentine condenser rotates, and the gaseous standard samples on the inner wall of the serpentine condenser slide slowly along the inner wall of the serpentine condenser under the action of centrifugal force. They merge with other small volume standard samples to form standard sample particles with larger volume and weight. At the same time, driven by the gas, they drip down along the discharge pipe into the collection bottle, thus removing the residual standard samples inside the serpentine condenser.

[0025] D: Rapidly cool the distillation flask.

[0026] The lifting platform pushes the support plate and the cooling box to rise, so that the cooling box can wrap around the heating plate and the lower part of the distillation flask, and quickly cool down the heating plate and the lower part of the distillation flask.

[0027] E: After the distillation flask has cooled and no further vapor is observed, remove the distillation flask and pour the residual standard into a 5 mL graduated cylinder. Invert the distillation flask over the graduated cylinder and allow the residual standard to drip down until the volume of liquid in the graduated cylinder does not increase significantly. Record the volume to an accuracy of 0.1 mL and record it as the residual percentage R. H Simultaneously, the percentage of maximum recovery volume R is derived based on the maximum recovery volume. max and residual percentage R H Calculate the percentage of loss L H ;

[0028] F: Repeat the measurement 3 times according to the procedure of step BE, take the average value of the 3 measurement results as the measurement value, and calculate the indication error according to formula (1);

[0029]

[0030] Where: ΔT—temperature indication error, °C;

[0031] —The percentage of recovery corresponds to the measured temperature, in °C;

[0032] T S —The percentage of recovery corresponds to the standard temperature, ℃.

[0033] G: Distillation temperature repeatability

[0034] The difference between the maximum and minimum values ​​of the three measurements for each standard sample in step C is taken as the measurement repeat.

[0035] Sex, calculated according to formula (2):

[0036] R = |T max -T m | Formula (2)

[0037] In the formula: R—distillation temperature repeatability, °C;

[0038] T max —The percentage of recovery corresponds to the measured temperature, in °C;

[0039] T min —The percentage of recovery corresponds to the standard temperature, ℃.

[0040] H: Based on the indication error and distillation temperature repeatability obtained from steps F and G, the calibration result is the corrected value or calibration value of the calibrated object, thereby determining the relationship between the indication value of the calibrated object and the corresponding value reproduced by the metrological standard, so as to achieve traceability of the value.

[0041] It also includes the following steps:

[0042] Step 1: Establish a measurement model

[0043] 1): Under the condition that the calibration method requirements are met, the indication error of the instrument under test is calculated by formula (1). Then, the sensitivity coefficient of the measurement uncertainty obtained by formula (1) is given by formula (3) and formula (4):

[0044]

[0045] C1 and C2 represent sensitivity coefficients, which are obtained by... Taking the partial derivative yields the result;

[0046] 2) The uncertainty propagation rate is obtained from formulas (1), (3), and (4) and is given by formula (5):

[0047]

[0048] Among them, u c (ΔT): The combined standard uncertainty of the measured quantity ΔT;

[0049] Input Standard uncertainty;

[0050] u(T s Input quantity T s Standard uncertainty;

[0051] Step 2: The main sources of uncertainty include (1) relative standard uncertainty introduced by distillation range reference materials; (2) relative standard uncertainty introduced by the repeatability of distillation range temperature measurement; and (3) relative standard uncertainty introduced by the measurement of the receiving volume of the distillation instrument.

[0052] (1): Relative standard uncertainty introduced by distillation range standard reference

[0053] The relative standard uncertainty of the distillation range standard is determined by using a Type B method for evaluation. This uncertainty is found by referring to the distillation temperature uncertainty u1 at 50% recovery volume as stated on the standard certificate. With a coverage factor of k=2, the relative standard uncertainty component introduced by the distillation range standard is calculated using formula (6):

[0054] u 1rel (T s)=u1 / 2 (6);

[0055] (2): Relative standard uncertainty introduced by the repeatability of distillation range temperature measurement

[0056] The distillation range temperature of a standard sample at a recovery volume of n% was repeatedly measured using an instrument temperature sensor. The three measurements were n1℃, n2℃, and n3℃, respectively. The standard uncertainty component introduced by the repeatability of the graduated cylinder was evaluated using the range method according to Type A criteria.

[0057]

[0058] Among them, T omax : Represents the maximum value among the measured values;

[0059] T omin : Represents the minimum value among the measured values;

[0060] C: Represents the range coefficient;

[0061] Then, the temperature is measured corresponding to the percentage of recovery. The relative standard uncertainty component introduced by the repeatability of the distillation range temperature measurement is calculated using formula (8):

[0062] (3): Relative standard uncertainty introduced by the volume measurement of the distillation instrument

[0063] Since the measured volume and the measured distillation temperature have a linear relationship—that is, as the volume of the distillate increases, the distillation temperature rises—we can assume that T = f(V). Therefore, we can conclude that the uncertain components of the two have a consistent relationship, i.e., u 2 rel (T)=u 2 rel (V); The evaluation is carried out according to the Type B method, with a coverage factor of k=2. The relative standard uncertainty component introduced by the receiving volume measurement is calculated according to formula (9):

[0064]

[0065] in,

[0066] Among them, V L Represents the percentage of loss, u rel (V) represents the standard uncertainty component introduced by the receiving volume measurement;

[0067] Step 3: Calculation of Combined Standard Uncertainty

[0068] Based on the components of the relative standard uncertainty in step two, the combined relative standard uncertainty is calculated using formula (10):

[0069]

[0070] u crel (ΔT): Represents the relative combined standard uncertainty of the measured quantity;

[0071] u 1rel (T S ): Represents the relative standard uncertainty component introduced by the standard reference material;

[0072] This represents the relative standard uncertainty component introduced by measurement repeatability;

[0073] This represents the relative standard uncertainty component introduced by the instrument's received volume measurement.

[0074] Step 4: Evaluation of Relative Expanded Uncertainty

[0075] Taking a confidence probability p = 95% and a coverage factor k = 2, the relative expanded uncertainty can be calculated as follows:

[0076] U rel (Tr)=u crel (ΔT)×2 (11)

[0077] Urel(Tr): Relative expanded uncertainty;

[0078] Step 5: Compare the parameters of the instrument being calibrated with the relative expanded uncertainty obtained in Step 3 to further provide the evaluation results;

[0079] The relative expanded uncertainty is compared with the instrument class requirements inherent in the calibrated instrument to determine whether it meets the requirements for daily use.

[0080] The beneficial effects of this invention are as follows:

[0081] 1. When there is no water vapor supply after the work is completed, the threaded rod can be rotated upwards to make the connecting pipe rise through the disc without contacting the rubber pad. During the process, the gas guide pipe will rise with the fixing block, and the gas supply pipe will be directly inserted into the inlet and move down against the fixing plate. Then the vent will be connected to the inside of the gas guide pipe. Start the gas charging device to introduce pure gas into the gas guide pipe through the gas supply pipe. The gas will then enter the serpentine condenser. Then disconnect the connection between the coolant inlet / outlet and the liquid supply end. At the same time, start the first motor to drive the second pulley to rotate. The drive belt will drive the first pulley to rotate, so that the tube cover will rotate with the installation end. The serpentine condenser will rotate, and the small volume liquid adhering to the inner wall of the serpentine condenser will slowly slide along the inner wall of the serpentine condenser under the action of centrifugal force and merge with other small volume liquids to form a larger volume and weight liquid. At the same time, driven by the gas, it will drip down along the discharge pipe into the collection bottle, which can clean the liquid inside the serpentine condenser more thoroughly and avoid waste.

[0082] 2. This invention involves pouring a solution into the distillation flask. When the solution reaches the graduation mark, any excess solution will drain out through the drain tube. The drained solution can be collected at the drain tube, ensuring a more accurate amount of solution poured into the distillation flask. Compared to the traditional method of adding solution little by little, it is easier to add too much or too little. A sealing plug is then inserted into the drain tube to block it, and the installation sleeve is tightened to secure it to the drain tube using threads. This prevents water vapor and solution from escaping from the drain tube when the solution is heated and boiled, thus achieving a sealing effect.

[0083] 3. This invention uses a lifting platform to push the support plate and the cooling box upwards, allowing the cooling box to enclose the lower part of the heating plate. Simultaneously, the three side plates surround the lower end of the distillation flask. The lower end of the heating plate is immersed in the coolant inside the cooling box. A first motor drives a stirring plate to rotate, thus agitating the coolant inside the cooling box and effectively cooling the heating plate. The coolant absorbs the heat from the heating plate and is then cooled by the cooling box, maintaining a consistently low temperature and accelerating the cooling of the heating plate. Simultaneously, the cold air from the coolant rises, surrounding the outside of the distillation flask and further accelerating its cooling, making it convenient for secondary use.

[0084] 4. The present invention calibrates the indicated value error and distillation temperature repeatability of the calibrated instrument, and obtains the corrected value or calibrated value of the calibrated object, as well as the main sources of uncertainty information, including (1) the relative standard uncertainty introduced by the distillation range standard material; (2) the relative standard uncertainty introduced by the distillation range temperature measurement repeatability; and (3) the relative standard uncertainty introduced by the distillation instrument receiving volume measurement. By synthesizing the standard uncertainty through these information, the relative expanded uncertainty is obtained, thereby determining the relationship between the indicated value of the calibrated object and the corresponding value reproduced by the metrological standard, so as to realize the traceability of the value. Attached Figure Description

[0085] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0086] Figure 2 This is a schematic diagram of the cross-sectional structure of the distillation flask of the present invention;

[0087] Figure 3 This is a schematic diagram of the connection between the connecting pipe and the mounting end of the present invention;

[0088] Figure 4 This is a schematic diagram of the cross-sectional structure of the serpentine condenser tube of the present invention;

[0089] Figure 5 This is a schematic cross-sectional view of the gas delivery pipe inserted into the port of the present invention.

[0090] Figure 6 This is a schematic cross-sectional view of the connection between the fixing block and the fixing plate of the present invention;

[0091] Figure 7 This is a schematic diagram of the internal cross-sectional structure of the refrigeration box of the present invention;

[0092] Figure 8 This is a schematic diagram of the side plate of the present invention wrapping around the heating plate and the distillation flask for cooling.

[0093] In the diagram: 1. Box body; 2. Working area A; 3. Working area B; 4. Control box; 5. Distillation flask; 501. Temperature measuring device; 502. Connecting end; 6. Branch pipe; 601. Hose; 7. Heating plate; 8. Refrigeration box; 801. Limiting slider; 802. Side plate; 9. Support plate; 901. Second motor; 902. Stirring plate; 10. Lifting platform; 11. Gas filling device; 111. Gas supply pipe; 112. Vent; 12. Threaded sleeve; 121. Threaded rod; 13. First motor; 131. 14. Pipe cover; 141. Coolant inlet / outlet; 15. Collection bottle; 16. Drain pipe; 17. Sealing plug; 171. Mounting sleeve; 18. Connecting pipe; 181. Disc; 19. Drive belt; 20. Mounting end; 201. Rubber pad; 21. First pulley; 22. Air guide pipe; 23. Support plate; 24. Serpentine condenser tube; 241. Discharge pipe; 25. Bearing; 26. Fixing block; 261. Insertion hole; 262. Spring; 263. Through port; 27. Fixing plate; 271. Insert rod. Detailed Implementation

[0094] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0095] like Figures 1 to 7As shown, this embodiment of the invention provides an automatic distillation range measuring instrument and its calibration method, including a housing 1, a distillation flask 5, and a tube cover 14. A working area A 2 is provided at the left end of the housing 1, and a working area B 3 is provided at the right end of the housing 1. A control box 4 is fixedly installed on the top of the housing 1. A heating plate 7 is fixedly connected inside the working area A 2. The upper surface of the heating plate 7 has positioning holes. A branch pipe 6 is fixedly installed on the housing 1. A connecting pipe 18 is fixedly connected to the right side of the branch pipe 6. A gas guide pipe 22 is fixedly installed on the connecting pipe 18. A fixing block 26 is fixedly connected inside the gas guide pipe 22. A fixing plate 27 is provided at the bottom of the fixing block 26. A fixing plate 27 is fixedly installed on the inner wall of the working area B 3. An inflation device 11 is connected to the top of the tube cover 14, an installation end 20 is fixedly installed on the top, a first pulley 21 is fixedly connected to the outer side of the upper end of the installation end 20, a drive belt 19 is sleeved on the outside of the first pulley 21, bearings 25 are fixedly installed on the outer side of the lower end of the installation end 20 and the outer side of the tube cover 14, a serpentine condenser tube 24 is fixedly installed inside the tube cover 14, a support plate 23 is fixedly connected to the inner wall of the B working area 3 and movably sleeved on the outside of the bearing 25, a first motor 13 is fixedly connected to the inner wall of the B working area 3, a collection bottle 15 located directly below the tube cover 14 is placed inside the B working area 3, and a threaded sleeve 12 is fixedly installed at the bottom of the control box 4.

[0096] The working principle and beneficial effects of the above technical solution are as follows: When there is no water vapor supply after the work is completed, the threaded rod 121 can be rotated upward so that it drives the connecting pipe 18 to rise through the disc 181 without contacting the rubber pad 201. During the process, the air guide pipe 22 will rise with the fixing block 26, and the air supply pipe 111 will be directly inserted into the inlet 263 and move downward against the fixing plate 27. Then the air inlet 112 will be connected to the inside of the air guide pipe 22, and the inflation device 11 will be started to introduce pure gas into the air guide pipe 22 through the air supply pipe 111. The gas will then enter the serpentine condenser pipe 24, and the first... The motor 13 drives the second pulley 131 to rotate, which in turn drives the first pulley 21 to rotate via the drive belt 19. This causes the tube cover 14 to rotate with the mounting end 20, and the serpentine condenser tube 24 to rotate. Small volumes of liquid adhering to the inner wall of the serpentine condenser tube 24 will slowly slide along the inner wall of the serpentine condenser tube 24 under the action of centrifugal force, and merge with other small volumes of liquid to form a larger volume and weight of liquid. At the same time, driven by the gas, it will drip down along the discharge pipe 241 into the collection bottle 15, which can clean the liquid inside the serpentine condenser tube 24 more thoroughly and avoid waste.

[0097] like Figures 1-7As shown, in one embodiment, a drain pipe 16 is fixedly connected to the outside of the distillation flask 5, and a sealing plug 17 is provided inside the drain pipe 16. A lifting platform 10 is fixedly connected inside the working area A 2, a support plate 9 is fixedly connected to the top of the lifting platform 10, and a refrigeration box 8 is fixedly connected to the top of the support plate 9.

[0098] The working principle and beneficial effects of the above technical solution are as follows: By pouring solution into the distillation flask 5, when the poured solution reaches the mark, the excess solution will be discharged from the drain pipe 16. The discharged solution can be collected at the drain pipe 16, ensuring that the amount of solution poured into the distillation flask 5 is accurate. Compared with the traditional method of adding solution little by little, it is easier to add too much or too little. Then, the sealing plug 17 is inserted into the drain pipe 16 to block it, and the installation sleeve 171 is screwed on to fix it to the drain pipe 16 using threads. This prevents water vapor and solution from escaping from the drain pipe 16 when the solution is heated and boiled, thus achieving a sealing effect. The lifting platform 10 pushes the support plate 9 and the refrigeration box 8 to rise, and the refrigeration box... 8. The lower part of the heating plate 7 is wrapped around it, and the three side plates 802 can surround the outer side of the lower end of the distillation flask 5, so that the lower end of the heating plate 7 is immersed in the coolant inside the cooling box 8. Then, the second motor 901 drives the stirring plate 902 to rotate, thereby stirring the coolant inside the cooling box 8, which can effectively cool the heating plate 7. The coolant absorbs the temperature of the heating plate 7, and then is cooled by the cooling box 8, keeping the coolant at a low temperature, which can accelerate the cooling speed of the heating plate 7. At the same time, the cold air from the coolant will rise, and the rising cold air will surround the outer side of the distillation flask 5, which can accelerate the cooling speed of the distillation flask 5 for use in the second operation.

[0099] like Figure 5 As shown, in one embodiment, an air supply pipe 111 is fixedly connected to the outside of the inflation device 11, and an air inlet 112 is provided at equal intervals along the outer side of the lower end of the air supply pipe 111.

[0100] The working principle and beneficial effects of the above technical solution are as follows: When the inflation device 11 is working, it will introduce gas into the gas supply pipe 111 and then release it through the air inlet 112, thereby realizing the flow of gas and facilitating the introduction of gas into the serpentine condenser 24.

[0101] like Figure 3 As shown, in one embodiment, a flexible hose 601 is fixedly connected to the outside of the branch pipe 6. The flexible hose 601 is fixedly connected to the connecting pipe 18. A disc 181 is fixedly installed on the outside of the connecting pipe 18. A threaded rod 121 that is movably connected to the disc 181 is movably sleeved in the middle of the threaded sleeve 12.

[0102] The working principle and beneficial effects of the above technical solution are as follows: the presence of the hose 601 allows the connecting pipe 18 to move up and down unimpeded when the branch pipe 6 is fixed, by rotating the threaded rod 121 along the inner wall of the threaded sleeve 12, thereby facilitating the adjustment of its position during operation.

[0103] like Figure 5 , 6 As shown, in one embodiment, the bottom of the fixing block 26 is provided with equidistant holes 261 along the annular axis, and a spring 262 is fixedly connected inside the holes 261. The middle part of the fixing block 26 has a through-hole 263, and the top of the fixing plate 27 is fixedly connected with a rod 271 fixedly connected to the spring 262 along the annular axis.

[0104] The working principle and beneficial effects of the above technical solution are as follows: When the height of the air duct 22 rises, the air supply pipe 111 is inserted into the port 263 and moves downward against the fixing plate 27, which allows the insertion rod 271 to slowly slide out of the insertion hole 261 and pull the spring 262 to make it elastic. At the same time, the fixing plate 27 is not in contact with the bottom of the fixing block 26, so that the air port 112 is connected to the inside of the air duct 22, allowing the pure gas input into the air supply pipe 111 to enter the air duct 22 through the air port 112. When the height of the air duct 22 falls, the air supply pipe 111 will be pulled out from the port 263, and the elastic spring 262 will pull the fixing plate 27 to be tightly attached to the bottom of the fixing block 26 and block the port 263. The automatic adjustment effect is good.

[0105] like Figure 4 As shown, in one embodiment, the mounting end 20 is a frustum-shaped structure, a rubber pad 201 is fixedly installed on the inner wall of the mounting end 20, a coolant inlet / outlet end 141 is fixedly connected to the outer side of the pipe cover 14, and a discharge pipe 241 is fixedly connected to the bottom of the pipe cover 14.

[0106] The working principle and beneficial effects of the above technical solution are as follows: By pressing the lowered connecting pipe 18 tightly against the rubber gasket 201, a sealing effect can be achieved at the connection between the mounting end 20 and the connecting pipe 18, preventing water vapor from escaping from the connection seam. At the same time, the moving connecting pipe 18 does not contact the rubber gasket 201, making the connection seam very small. This not only does not affect the rotation of the mounting end 20, but also ensures that less pure gas is lost from the inside of the serpentine condenser tube 24. Refrigerant is introduced into the tube cover 14 through the coolant inlet / outlet 141, keeping the serpentine condenser tube 24 at a low temperature. When water vapor encounters the cold, it will adhere to the inner wall of the serpentine condenser tube 24 to form a liquid. The liquid adhering to the inner wall of the serpentine condenser tube 24 will drip down through the outlet pipe 241.

[0107] like Figure 1 , 2As shown, in one embodiment, a second pulley 131 is fixedly connected to the bottom of the first motor 13, a drive belt 19 is sleeved on the outside of the second pulley 131, a temperature measuring device 501 is fixedly connected to the top of the distillation flask 5, and a connecting end 502 is fixedly installed on the outside of the distillation flask 5.

[0108] The working principle and beneficial effects of the above technical solution are as follows: starting the first motor 13 can drive the second pulley 131 to rotate, thereby driving the first pulley 21 to rotate through the drive belt 19, thus realizing the rotation of the tube cover 14; the temperature inside the distillation flask 5 can be detected through the temperature measuring device 501, and it can be connected to the branch pipe 6 through the connecting end 502.

[0109] like Figure 2 As shown, in one embodiment, an installation sleeve 171 is fixedly installed on the outside of the sealing plug 17, and threads are engraved on the outer wall of the drain pipe 16 and the inner wall of the installation sleeve 171.

[0110] The working principle and beneficial effects of the above technical solution are as follows: the sealing plug 17 is inserted into the drain pipe 16 to block it, and the installation sleeve 171 is screwed on to fix it to the drain pipe 16 by means of threads, which can prevent water vapor and solution from being discharged from the drain pipe 16 when the solution is heated and boiled, thus achieving a sealing effect.

[0111] like Figure 1 , 7 As shown, in one embodiment, a second motor 901 is fixedly installed on the top of the support plate 9, and an agitator 902 located inside the refrigeration box 8 is fixedly installed on the top of the second motor 901. A slide is provided on the inner wall of the working area 2. Limiting sliders 801 that are slidably connected inside the slide are fixedly installed on both sides of the refrigeration box 8. Side plates 802 are fixedly connected to the top of the three sides of the refrigeration box 8.

[0112] The working principle and beneficial effects of the above technical solution are as follows: When the lifting platform 10 pushes the support plate 9 and the refrigeration box 8 to rise, the limit sliders 801 on both sides will slide along the slide rail, so that the refrigeration box 8 will wrap around the lower part of the heating plate 7. At the same time, the side plates 802 on the three sides can surround the lower end of the distillation flask 5, so that the lower end of the heating plate 7 is immersed in the water-cooling liquid inside the refrigeration box 8. Then, the second motor 901 drives the stirring plate 902 to rotate, thereby stirring the water-cooling liquid inside the refrigeration box 8, which can effectively cool the heating plate 7. The water-cooling liquid will absorb the temperature of the heating plate 7, and then be cooled by the refrigeration box 8, so that the water-cooling liquid is always kept at a low temperature, which can accelerate the cooling speed of the heating plate 7. At the same time, the cold air of the water-cooling liquid will escape upward, and the continuously rising cold air will surround the outside of the distillation flask 5, which can accelerate the cooling speed of the distillation flask 5 and facilitate its use in secondary work.

[0113] Working principle and usage process:

[0114] First, pour the solution into the distillation flask 5. When the solution reaches the mark, the excess solution will be discharged from the drain pipe 16. The discharged solution is collected at the drain pipe 16 to ensure that the amount of solution poured into the distillation flask 5 is accurate.

[0115] Next, by rotating the threaded rod 121, it is slowly slid out of the threaded sleeve 12 using the thread, and the connecting tube 18 is moved down by the disc 181 until it is inserted into the installation end 20 and pressed tightly against the rubber gasket 201, so that the connection between the two can be sealed.

[0116] Then, by activating the heating plate 7, the distillation flask 5 is heated, and the water vapor generated by the solution inside is introduced into the serpentine condenser 24 through the branch pipe 6, connecting pipe 18 and mounting end 20. Refrigerant is introduced into the tube cover 14 through the coolant inlet / outlet end 141, so that the serpentine condenser 24 is kept at a low temperature. When the water vapor encounters the cold, it will adhere to the inner wall of the serpentine condenser 24 to form a liquid. As it gradually increases, it will slide down the inner wall into the collection bottle 15.

[0117] When there is no water vapor supply after the work is finished, the threaded rod 121 can be rotated upward so that it drives the connecting pipe 18 to rise through the disc 181 without contacting the rubber pad 201. During the process, the air guide pipe 22 will rise with the fixing block 26, and the air supply pipe 111 will be directly inserted into the opening 263 and move down against the fixing plate 27. Then the air opening 112 will be connected to the inside of the air guide pipe 22.

[0118] Restart the gas charging device 11 and introduce pure gas into the gas pipe 22 through the gas supply pipe 111. The gas will then enter the serpentine condenser tube 24. Then disconnect the coolant inlet / outlet 141 from the liquid supply end. At the same time, start the first motor 13 to drive the second pulley 131 to rotate. The drive belt 19 will drive the first pulley 21 to rotate, so that the tube cover 14 will rotate with the installation end 20. The serpentine condenser tube 24 will rotate, and the small volume liquid adhering to the inner wall of the serpentine condenser tube 24 will slowly slide along the inner wall of the serpentine condenser tube 24 under the action of centrifugal force. It will merge with other small volume liquids to form a larger volume and weight of liquid. At the same time, driven by the gas, it will drip down along the discharge pipe 241 into the collection bottle 15, which can clean the liquid inside the serpentine condenser tube 24 more thoroughly and avoid waste.

[0119] The lifting platform 10 pushes the support plate 9 and the cooling box 8 to rise, allowing the cooling box 8 to enclose the lower part of the heating plate 7. At the same time, the three side plates 802 can surround the lower end of the distillation flask 5, immersing the lower end of the heating plate 7 in the coolant inside the cooling box 8. Then, the second motor 901 drives the stirring plate 902 to rotate, thereby agitating the coolant inside the cooling box 8, which can effectively cool the heating plate 7. The coolant absorbs the temperature of the heating plate 7 and is then cooled by the cooling box 8, keeping the coolant at a low temperature, which can accelerate the cooling speed of the heating plate 7. At the same time, the cold air from the coolant will escape upwards, and the rising cold air will surround the outside of the distillation flask 5, which can accelerate the cooling speed of the distillation flask 5 for use in secondary operations.

[0120] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0121] A calibration method for an automatic distillation range meter includes the following steps:

[0122] A: Preparations

[0123] A1: Measure 100 mL of standard sample

[0124] Inject the standard sample into the distillation flask. Excess standard sample will flow out from the drain tube. Once the standard sample stops flowing out, seal the stopper. Then place the distillation flask into the positioning hole on the upper surface of the heating plate.

[0125] A2: Determine the location of the temperature measuring device

[0126] When the temperature measuring device uses a mercury thermometer, the thermometer bulb should be positioned on the center line, and the bottom of the mercury capillary tube should be flush with the bottom of the inner wall of the branch tube.

[0127] When a platinum resistance thermometer is used in the temperature measuring device, the upper ends of the two parallel platinum wires are flush with the bottom of the inner wall of the branch pipe.

[0128] A3: Check the instrument's sealing.

[0129] Check the sealing between the mouth of the distillation flask and the temperature measuring device, between the distillation flask and the branch pipe, and between the branch pipe and the connecting pipe;

[0130] B: Set the heating program for the control box according to the standard sample, heat the standard sample, distill at a rate of 45 mL / min, and automatically record the initial boiling point IBP, the temperature reading at 5% recovery volume, the temperature reading at 10% recovery volume, the temperature reading at each multiple of 10% recovery volume, the final boiling point FBP, and the measured atmospheric pressure; at the same time, record the maximum recovery volume Vmax and the corresponding temperature. After reaching the final boiling point, when the temperature is raised to the highest point according to the heating program, the instrument stops the heating program, and the entire distillation range test is completed.

[0131] C: After the distillation range test is completed, clean the remaining standard sample inside the serpentine condenser.

[0132] Rotate the threaded rod upwards to make it rise through the disc and drive the connecting pipe upwards without contacting the rubber pad. During the process, the gas guide pipe drives the fixed block upwards, and the gas supply pipe is directly inserted into the inlet and moves downwards against the fixed plate. Then the inlet is connected to the inside of the gas guide pipe. Start the gas filling device and introduce pure gas into the gas guide pipe through the gas supply pipe. The gas is then introduced into the serpentine condenser to remove residual standard samples. At the same time, start the first motor to make the tube cover rotate with the installation end. The serpentine condenser rotates, and the gaseous standard samples on the inner wall of the serpentine condenser slide slowly along the inner wall of the serpentine condenser under the action of centrifugal force. They merge with other small volume standard samples to form standard sample particles with larger volume and weight. At the same time, driven by the gas, they drip down along the discharge pipe into the collection bottle, thus removing the residual standard samples inside the serpentine condenser.

[0133] D: Rapidly cool the distillation flask.

[0134] The lifting platform pushes the support plate and the cooling box to rise, so that the cooling box can wrap around the heating plate and the lower part of the distillation flask, and quickly cool down the heating plate and the lower part of the distillation flask.

[0135] E: After the distillation flask has cooled and no further vapor is observed, remove the distillation flask and pour the residual standard into a 5 mL graduated cylinder. Invert the distillation flask over the graduated cylinder and allow the residual standard to drip down until the volume of liquid in the graduated cylinder does not increase significantly. Record the volume to an accuracy of 0.1 mL and record it as the residual percentage R. H Simultaneously, the percentage of maximum recovery volume R is derived based on the maximum recovery volume. max and residual percentage R H Calculate the percentage of loss L H ;

[0136] F: Repeat the measurement 3 times according to the procedure of step BE, take the average value of the 3 measurement results as the measurement value, and calculate the indication error according to formula (1);

[0137]

[0138] Where: ΔT—temperature indication error, °C;

[0139] —The percentage of recovery corresponds to the measured temperature, in °C;

[0140] T S —The percentage of recovery corresponds to the standard temperature, ℃.

[0141] Table 1 shows the distillation range measurement results for a certain oil sample.

[0142] Table 1. Distillation range measurement results of a certain oil sample

[0143]

[0144] G: Distillation temperature repeatability

[0145] The difference between the maximum and minimum values ​​of the three measurements for each standard sample in step C is taken as the measurement repeatability, and calculated according to formula (2):

[0146] R = |T max -T m | Formula (2)

[0147] In the formula: R—distillation temperature repeatability, °C;

[0148] T max —The percentage of recovery corresponds to the measured temperature, in °C;

[0149] T min —The percentage of recovery corresponds to the standard temperature, ℃.

[0150] Table 2 Standard deviation of six measurements of a certain oil sample

[0151] Table 2 Standard deviation of six measurements of a certain oil sample

[0152]

[0153] H: Based on the indication error and distillation temperature repeatability obtained from steps F and G, the calibration result is the corrected value or calibration value of the calibrated object, thereby determining the relationship between the indication value of the calibrated object and the corresponding value reproduced by the metrological standard, so as to achieve traceability of the value.

[0154] The calibration method for the automatic distillation range measuring instrument further includes the following steps:

[0155] Step 1: Establish a measurement model

[0156] 1): Under the condition that the calibration method requirements are met, the indication error of the instrument under test is calculated by formula (1). Then, the sensitivity coefficient of the measurement uncertainty obtained by formula (1) is given by formula (3) and formula (4):

[0157]

[0158] C1 and C2 represent sensitivity coefficients, which are obtained by... Taking the partial derivative yields the result;

[0159] 2) The uncertainty propagation rate is obtained from formulas (1), (3), and (4) and is given by formula (5):

[0160]

[0161] Among them, u c (ΔT): The combined standard uncertainty of the measured quantity ΔT;

[0162] Input Standard uncertainty;

[0163] u(T s Input quantity T s Standard uncertainty;

[0164] Step 2: The main sources of uncertainty include (1) relative standard uncertainty introduced by distillation range reference materials; (2) relative standard uncertainty introduced by the repeatability of distillation range temperature measurement; and (3) relative standard uncertainty introduced by the measurement of the receiving volume of the distillation instrument.

[0165] (1): Relative standard uncertainty introduced by distillation range standard reference

[0166] The relative standard uncertainty of the distillation range standard is determined by using a Type B method for evaluation. This uncertainty is found by referring to the distillation temperature uncertainty u1 at 50% recovery volume as stated on the standard certificate. With a coverage factor of k=2, the relative standard uncertainty component introduced by the distillation range standard is calculated using formula (6):

[0167] u 1rel (T S )=u1 / 2 (6);

[0168] Taking toluene distillation range standard reference as an example, a Type B method is used for evaluation. The standard reference certificate provides a distillation range temperature uncertainty of 0.60% at a recovery volume of 50%. Using a coverage factor k=2, the relative standard uncertainty components are:

[0169] u 1rel (T S ) = 0.60% 2 = 0.30%

[0170] (2): Relative standard uncertainty introduced by the repeatability of distillation range temperature measurement

[0171] The distillation range temperature of a standard sample at 50% recovery volume was repeatedly measured using an instrument temperature sensor. The three measurements were 109.5℃, 109.3℃, and 109.2℃, respectively. Using the range method and a Type A method for evaluation, the standard uncertainty component introduced by the repeatability of the graduated cylinder is:

[0172]

[0173] The recovery percentage corresponds to a measured temperature of T0 = 109.3℃. Since the actual number of measurements was 2, the relative standard uncertainty component introduced by the repeatability of the distillation range temperature measurement is calculated using formula (8):

[0174]

[0175] (3): Relative standard uncertainty introduced by the volume measurement of the distillation instrument

[0176] Since the measured volume and the measured distillation temperature have a linear relationship—that is, as the volume of the distillate increases, the distillation temperature rises—we can assume that T = f(V). Therefore, we can conclude that the uncertain components of the two have a consistent relationship, i.e., u 2 rel (T)=u 2 rel (V);

[0177] Based on experience in visually observing and reading 100mL graduated cylinders, here, when the recovery volume is 50%, follow V... L Calculating based on a visual error of 0.3 mL, the standard uncertainty component introduced by the volume measurement received by the distillation apparatus is:

[0178]

[0179] The evaluation is conducted according to the Type B method, with a coverage factor of k=2. The relative standard uncertainty component introduced by the receiving volume measurement is calculated using formula (9):

[0180]

[0181] Among them, V L Represents the percentage of loss, u rel (V) represents the standard uncertainty component introduced by the receiving volume measurement;

[0182] Step 3: Calculation of Combined Standard Uncertainty

[0183] According to Table 3, which summarizes the components of the relative standard uncertainty in step two,

[0184] Summary table of components of relative standard uncertainty

[0185]

[0186] The combined relative standard uncertainty is then calculated using formula (10):

[0187]

[0188] Step 4: Evaluation of Relative Expanded Uncertainty

[0189] Taking a confidence probability p = 95% and a coverage factor k = 2, the relative expanded uncertainty can be calculated as follows:

[0190] U rel (T r )=0.44×2=0.44×2=1% (11)

[0191] U rel (Tr): Relative expanded uncertainty;

[0192] Step 5: Compare the parameters of the instrument being calibrated with the relative expanded uncertainty obtained in Step 3 to further provide the evaluation results;

[0193] The relative expanded uncertainty is compared with the instrument class requirements inherent in the calibrated instrument to determine whether it meets the requirements for daily use.

[0194] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic distillation range measuring instrument, comprising a housing (1), a distillation flask (5), and a tube cover (14), characterized in that: The left end of the box (1) is provided with a working area A (2), the right end of the box (1) is provided with a working area B (3), the top of the box (1) is fixedly installed with a control box (4), the inside of the working area A (2) is fixedly connected with a heating plate (7), the upper surface of the heating plate (7) is provided with positioning holes, the outside of the distillation flask (5) is fixedly installed with a connecting end (502), the distillation flask (5) is set on the heating plate (7), the box (1) is fixedly installed with a branch pipe (6), the left side of the branch pipe (6) is sleeved with the connecting end (502) on the outside of the distillation flask, the right side of the branch pipe (6) is fixedly connected with a connecting pipe (18), the connecting pipe (18) An air guide tube (22) is fixedly installed on the upper part of the work area (3). A fixing block (26) is fixedly connected inside the air guide tube (22). A fixing plate (27) is provided at the bottom of the fixing block (26). An insertion hole (261) is provided at equal intervals along the annular axis at the bottom of the fixing block (26). A spring (262) is fixedly connected inside the insertion hole (261). A through-hole (263) is passed through the middle of the fixing block (26). An insertion rod (271) fixedly connected to the spring (262) is fixedly connected at equal intervals along the annular axis at the top of the fixing plate (27). An inflation device (11) is fixedly connected to the inner wall of the B working area (3). An inflation device (11) is fixedly connected to the outside of the inflation device (11). A gas pipe (111) is provided. An installation end (20) is fixedly installed on the top of the pipe cover (14). A rubber pad (201) is fixedly installed on the inner wall of the installation end (20). A first pulley (21) is fixedly connected to the outer side of the upper end of the installation end (20). A drive belt (19) is sleeved on the outside of the first pulley (21). Bearings (25) are fixedly installed on the outer side of the lower end of the installation end (20) and on the outer side of the pipe cover (14). A serpentine condenser tube (24) is fixedly installed inside the pipe cover (14). A first support plate (23) is movably sleeved on the outer side of the bearing (25) and fixedly connected to the inner wall of the B working area (3). (3) is fixedly connected to the inner wall of the first motor (13), and the bottom of the first motor (13) is fixedly connected to the second pulley (131). The drive belt (19) is sleeved on the outside of the second pulley (131). The inside of the working area B (3) is a collection bottle (15) located directly below the tube cover (14). The bottom of the tube cover (14) is fixedly connected to the discharge pipe (241). The bottom of the control box (4) is fixedly installed with a threaded sleeve (12). The outside of the connecting pipe (18) is fixedly installed with a disc (181). The middle of the threaded sleeve (12) is movably sleeved with a threaded rod (121) that is movably connected to the disc (181). Rotate the threaded rod upwards to make it rise through the disc, causing the connecting pipe to rise without contacting the rubber pad. During this process, the gas guide pipe drives the fixed block to rise, and the gas supply pipe is directly inserted into the inlet and moves downward against the fixed plate. The inlet then connects with the inside of the gas guide pipe. Start the gas filling device and introduce pure gas into the gas guide pipe through the gas supply pipe. The gas then enters the serpentine condenser to remove residual standard samples. At the same time, start the first motor to make the tube cover rotate with the installation end. The serpentine condenser rotates, and the residual standard samples on the inner wall of the serpentine condenser slide slowly along the inner wall of the serpentine condenser under the action of centrifugal force. They merge with other small-volume standard samples to form larger standard sample particles. At the same time, driven by the gas, they drip down along the discharge pipe into the collection bottle, thus removing the residual standard samples inside the serpentine condenser.

2. The automatic distillation range measuring instrument according to claim 1, characterized in that: The distillation flask (5) is fixedly connected to the outside of a drain pipe (16), and a sealing plug (17) is provided inside the drain pipe (16). The working area A (2) is fixedly connected to a lifting platform (10), and a second support plate (9) is fixedly connected to the top of the lifting platform (10). A refrigeration box (8) is fixedly connected to the top of the second support plate (9). An installation sleeve (171) is fixedly installed on the outside of the sealing plug (17). Threads are engraved on the outer wall of the drain pipe (16) and the inner wall of the installation sleeve (171).

3. An automatic distillation range measuring instrument according to claim 2, characterized in that: The lower end of the gas pipe (111) has equidistant vents (112) on the outer side along a ring.

4. An automatic distillation range measuring instrument according to claim 3, characterized in that: A flexible hose (601) is fixedly connected to the outside of the branch pipe (6), and the flexible hose (601) is fixedly connected to the connecting pipe (18).

5. An automatic distillation range measuring instrument according to claim 4, characterized in that: The mounting end (20) has a frustum-shaped structure, and the coolant inlet / outlet end (141) is fixedly connected to the outside of the tube cover (14).

6. An automatic distillation range measuring instrument according to claim 5, characterized in that: A temperature measuring device (501) is fixedly connected to the top of the distillation flask (5).

7. An automatic distillation range measuring instrument according to claim 6, characterized in that: A second motor (901) is fixedly installed on the top of the second support plate (9), and an agitator (902) located inside the refrigeration box (8) is fixedly installed on the top of the second motor (901). A slide is provided on the inner wall of the working area A (2). Limiting sliders (801) that are slidably connected inside the slide are fixedly installed on both sides of the refrigeration box (8). Side plates (802) are fixedly connected to the top of the three sides of the refrigeration box (8).

8. A calibration method for an automatic distillation range measuring instrument according to claim 7, characterized in that: Includes the following steps: A: Preparations A1: Measure 100 mL of standard sample Inject the standard sample into the distillation flask. Excess standard sample will flow out from the drain tube. Once the standard sample stops flowing out, seal the stopper. Then place the distillation flask into the positioning hole on the upper surface of the heating plate. A2: Determine the location of the temperature measuring device When the temperature measuring device uses a mercury thermometer, the thermometer bulb should be positioned on the center line, and the bottom of the mercury capillary tube should be flush with the bottom of the inner wall of the branch tube. When a platinum resistance thermometer is used in the temperature measuring device, the upper ends of the two parallel platinum wires are flush with the bottom of the inner wall of the branch pipe. A3: Check the instrument's sealing. Check the sealing between the mouth of the distillation flask and the temperature measuring device, between the distillation flask and the branch pipe, and between the branch pipe and the connecting pipe; B: Based on the standard sample, set the heating program for the control box, heat the standard sample, distill at a rate of 45 mL / min, and automatically record the initial boiling point (IBP), the temperature reading at 5% recovery volume, the temperature reading at 10% recovery volume, the temperature reading at each multiple of 10% recovery volume, the final boiling point (FBP), and the measured atmospheric pressure; simultaneously record the maximum recovery volume. The instrument stops heating when the temperature reaches the highest point after the final boiling point is reached, and the entire distillation range test is completed. C: After the distillation range test is completed, remove any residual standard sample from inside the serpentine condenser. Rotate the threaded rod upwards to make it rise through the disc and drive the connecting pipe upwards without contacting the rubber pad. During this process, the gas guide pipe drives the fixed block upwards, and the gas supply pipe is directly inserted into the inlet and moves downwards against the fixed plate. The inlet then connects with the inside of the gas guide pipe. Start the gas filling device and introduce pure gas into the gas guide pipe through the gas supply pipe. The gas then enters the serpentine condenser to remove residual standard samples. At the same time, start the first motor to make the tube cover rotate with the installation end. The serpentine condenser rotates, and the residual standard samples on the inner wall of the serpentine condenser slide slowly along the inner wall of the serpentine condenser under the action of centrifugal force. They merge with other small volume standard samples to form standard sample particles with larger volume and weight. At the same time, driven by the gas, they drip down along the discharge pipe into the collection bottle, thus removing the residual standard samples inside the serpentine condenser. D: Rapidly cool the distillation flask. The lifting platform pushes the support plate and the cooling box to rise, so that the cooling box can wrap around the heating plate and the lower part of the distillation flask, and quickly cool down the heating plate and the lower part of the distillation flask. E: After the distillation flask has cooled and no further vapor is observed, remove the distillation flask and pour the residual standard into a 5mL graduated cylinder. Invert the distillation flask over the graduated cylinder and allow the residual standard to drip down until the volume of liquid in the graduated cylinder does not increase significantly. Record the volume to an accuracy of 0.1mL as the residual percentage. Simultaneously, the percentage of the maximum recovery volume is derived based on the maximum recovery volume. and residual percentage Calculate the percentage of loss ; F: Repeat the measurement 3 times according to the procedure of step BE, take the average value of the 3 measurement results as the measurement value, and calculate the indication error according to formula (1); G: Distillation temperature repeatability The difference between the maximum and minimum values ​​of the three measurements for each standard sample in step C is taken as the measurement repeatability, and calculated according to formula (2): In the formula: R—distillation temperature repeatability, °C; —The maximum value of the measured temperature corresponding to the percentage of recovery, in °C; —The minimum standard temperature corresponding to the recovery percentage, in °C; H: Based on the indication error and distillation temperature repeatability obtained from steps F and G, the calibration result is the corrected value or calibration value of the calibrated object, thereby determining the relationship between the indication value of the calibrated object and the corresponding value reproduced by the metrological standard, so as to achieve traceability of the value.

9. The calibration method according to claim 8, characterized in that: It also includes the following steps: Step 1: Establish a measurement model 1): Under the condition that the calibration method requirements are met, the indication error of the instrument under test is calculated by formula (1). Then, the sensitivity coefficient of the measurement uncertainty obtained by formula (1) is given by formula (3) and formula (4): — Represents the sensitivity coefficient, Through respectively Taking the partial derivative yields the result; 2) The uncertainty propagation rate is obtained by formulas (1), (3) and (4) and is then expressed as formula (5): （5） in, Combined standard uncertainty of the measured quantity ΔT; Input quantity Standard uncertainty; Input quantity Standard uncertainty; Step 2: The main sources of uncertainty include (1) relative standard uncertainty introduced by distillation range reference materials; (2) relative standard uncertainty introduced by the repeatability of distillation range temperature measurement; and (3) relative standard uncertainty introduced by the measurement of the receiving volume of the distillation instrument. (1): Relative standard uncertainty introduced by distillation range standard reference The relative standard uncertainty of the standard reference material was evaluated using a Type B method, based on the distillation temperature uncertainty at 50% recovery volume as stated on the standard reference material certificate. u 1 If the inclusion factor is k=2, then the relative standard uncertainty component introduced by the distillation range standard material can be calculated using formula (6): （6）； (2): Relative standard uncertainty introduced by the repeatability of distillation range temperature measurement The distillation range temperature of a standard sample at a recovery volume of n% was repeatedly measured using an instrument temperature sensor. The three measurements were n1℃, n2℃, and n3℃, respectively. The standard uncertainty component introduced by the repeatability of the graduated cylinder was evaluated using the range method according to Type A criteria. （7） in, This represents the maximum value among the measured values; This represents the minimum value among the measured values; C: Represents the range coefficient; Then, the temperature is measured corresponding to the percentage of recovery. The relative standard uncertainty component introduced by the repeatability of the distillation range temperature measurement is calculated using formula (8): (8) (3): Relative standard uncertainty introduced by the volume measurement of the distillation instrument Since there is a linear relationship between the measured volume of the distillate and the measured distillation temperature, i.e., as the volume of the distillate increases, the distillation temperature rises, it can be considered that... Therefore, it can be concluded that the uncertain components of the two have a consistent relationship, that is... The evaluation is conducted according to the Type B method, with a coverage factor of k=2. The relative standard uncertainty component introduced by the receiving volume measurement is calculated according to formula (9): （9）， Among them, u rel (V) represents the standard uncertainty component introduced by the receiving volume measurement; Step 3: Calculation of Combined Standard Uncertainty Based on the components of the relative standard uncertainty in step two, the combined relative standard uncertainty is calculated using formula (10): （10） : Represents the relative combined standard uncertainty of the measured quantity; : Represents the relative standard uncertainty component introduced by the standard reference material; : Represents the relative standard uncertainty component introduced by measurement repeatability; : Represents the relative standard uncertainty component introduced by the instrument's received volume measurement; Step 4: Evaluation of Relative Expanded Uncertainty Take confidence probability p= With a coverage factor of 95% and a coverage factor of k=2, the relative expanded uncertainty can be calculated as follows: （11） Urel(Tr): Relative expanded uncertainty; Step 5: Compare the parameters of the instrument being calibrated with the relative expanded uncertainty obtained in Step 3 to provide a more accurate evaluation result; The relative expanded uncertainty is compared with the instrument class requirements inherent in the calibrated instrument to determine whether it meets the requirements for daily use.

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