Comparison test device, test method and evaluation method for heat conduction capability of floor heating pipe

Abstract

The invention discloses a floor heating pipe heat conduction capability comparison test device, a test method and an evaluation method, and the device comprises a constant temperature water tank containing water, the top of the constant temperature water tank is provided with a tank cover, the bottom of the constant temperature water tank is provided with a constant temperature heater, the tank cover is provided with two station ports communicated with the interior of the constant temperature water tank, and the two station ports are respectively provided with a left contact and a right contact. The left contact and the right contact are connected with the temperature measurement display timer through lines; the bottom of the to-be-detected pipe is closed, the to-be-detected pipe is filled with liquid, the upper end of the to-be-detected pipe is provided with a sealing end cap, the to-be-detected pipe extends into the constant-temperature water tank through the station opening, the lower end of the to-be-detected pipe is immersed in water in the constant-temperature water tank, and the upper end of the to-be-detected pipe is fixed to the station opening through the sealing end cap; and the other end is connected with the temperature measurement display timer through a line. Through the device, the heat conduction capabilities of different pipes can be simply, conveniently and quickly compared, and meanwhile, the quality of the heat conduction capabilities of the floor heating pipes in the production process can be compared and evaluated.

Description

Technical Field

[0001] The present invention relates to the field of pipe testing, and in particular to a comparative testing device, a testing method and an evaluation method for thermal conductivity of floor heating pipes. Background Art

[0002] With the increasing application of floor radiant heating in the field of home heating, people's performance requirements for floor heating pipes are also getting higher and higher. However, the thermal conductivity of ordinary pipes such as PERT and PPR is relatively low. When used in the heating field, it will affect the heat dissipation rate of floor heating pipes. Therefore, the thermal conductivity of floor heating pipes has gradually become an important evaluation indicator of floor heating pipe products, and it is also a quality item that floor heating pipe manufacturers need to focus on controlling during the production process. However, due to the diverse production processes of floor heating pipes, different manufacturers, different raw materials, different formulas, and different equipment produce floor heating pipes with varying thermal conductivity. Therefore, it is necessary to establish effective inspection and analysis methods for the quality control of the thermal conductivity of floor heating pipes in order to effectively regulate the market and ensure the quality stability of the thermal conductivity of floor heating pipe products.

[0003] At present, the quality inspection method for the thermal conductivity of floor heating pipes can evaluate the thermal conductivity of floor heating pipes by measuring the thermal conductivity coefficient of floor heating pipes. However, the equipment for measuring the thermal conductivity coefficient is expensive and the operation is complicated. In addition, when comparing the thermal conductivity of multiple floor heating pipe samples, the thermal conductivity coefficient of each pipe sample must be tested separately before comparative evaluation. There are problems such as long comparative test cycle, low test efficiency and high test cost. In addition, this detection method requires first preparing samples of the raw materials of the floor heating pipes and then comparing and evaluating the quality of the thermal conductivity by measuring the thermal conductivity coefficient. The quality of the thermal conductivity cannot be directly compared and evaluated by preparing samples of the floor heating pipes. The sample preparation is complicated, the comparison is not intuitive, the quality inspection evaluation method is cumbersome, and the comparison of the thermal conductivity of multi-layer composite pipes of different materials is limited. Therefore, the current detection method for the thermal conductivity of floor heating pipes still has some shortcomings, and also restricts the company's rapid inspection, quality evaluation and improvement of the quality assurance capabilities of the product during the production process of floor heating pipes, affecting the quality stability of the thermal conductivity of floor heating pipe products. Summary of the Invention

[0004] The present invention provides a device, method, and evaluation method for comparing the thermal conductivity of floor heating pipes. This device allows for a quick and easy comparison of the thermal conductivity of different pipes. It also allows for a comparative evaluation of the thermal conductivity quality of floor heating pipes during production, thereby improving the quality stability of the product's thermal conductivity. The specific technical solution is as follows: A device for comparing and testing the thermal conductivity of floor heating pipes includes a constant temperature water tank, characterized in that the constant temperature water tank is filled with water, a box cover is provided on the top of the constant temperature water tank, and a constant temperature heater is provided at the bottom of the constant temperature water tank, and the water in the constant temperature water tank can be heated by the constant temperature heater to ensure that the water in the constant temperature water tank is always within a required water temperature range; two work station openings are provided on the box cover, the two work station openings are connected to the interior of the constant temperature water tank, and the two work station openings are provided with left and right contacts, and the left and right contacts are connected to a temperature measuring display timer through a circuit; the bottom of the pipe to be tested is closed, the interior is filled with liquid, and a sealing end cap is provided at the upper end, the pipe to be tested is extended into the constant temperature water tank through the work station opening, the lower end of the pipe to be tested is immersed in the water in the constant temperature water tank, the upper end of the pipe to be tested is fixed at the work station opening by the sealing end cap, a probe is provided in the middle of the sealing end cap, one end of the probe is extended into the pipe to be tested and immersed in the liquid in the pipe to be tested, and the other end of the probe is connected to the temperature measuring display timer through a circuit.

[0005] Furthermore, the temperature measurement and display timer includes a housing and a circuit board disposed in the housing, the circuit board being provided with a microprocessor, a temperature measurement module, a timing module, an input keyboard, a time display, and a temperature display, the temperature measurement module, the timing module, the input keyboard, the time display, and the temperature display being electrically connected to the microprocessor via wires, respectively, the input keyboard, the time display, and the temperature display being disposed on the outer surface of the housing, the temperature T being pre-set via the input keyboard as the endpoint temperature of the liquid inside the pipe to be measured; The timing module is connected to the left and right contacts through a circuit. When the pipe to be tested is placed in the work station, the sealing end cap on its upper end triggers the left and right contacts, and the timing module starts timing. The temperature measurement module is connected to the probe via a circuit. The probe can measure the initial temperature T1 of the liquid inside the pipe. As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to continue to rise. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time it takes for the liquid inside the pipe to go from the initial temperature T1 to the end temperature T. The temperature display is used to display the preset end point temperature T and the initial temperature T1 of the liquid inside the pipe; the time display is used to display the time t used by the liquid inside the pipe to change from the initial temperature T1 to the end point temperature T.

[0006] Furthermore, a reset button is provided on the circuit board. The reset button is exposed outside the shell and is electrically connected to the microprocessor through a wire. After completing the recording of the initial temperature T1, end temperature T and time t of the liquid inside the pipe, the pipe is taken out and the reset button is clicked to clear the data display and reset the temperature display timer to wait for a new test.

[0007] Furthermore, a memory and a communication unit are also provided on the circuit board. The memory and the communication unit are electrically connected to the microprocessor through wires respectively. The memory is used to store the signals processed by the microprocessor. The records in the memory can be retrieved through the input keyboard and displayed through the display; the communication unit can connect and send the signals processed by the microprocessor to an external device.

[0008] Furthermore, a power supply is provided in the housing, and the power supply is a lithium battery. The power supply is connected to the microprocessor and provides power to each unit on the circuit board through the microprocessor.

[0009] Furthermore, the box cover is provided with sealing grooves near the two workstation openings. After the pipe to be tested passes through the workstation opening and enters the constant temperature water tank, the sealing end cap at the upper end of the pipe to be tested fits tightly with the sealing groove.

[0010] Furthermore, the sealing end cap includes a top cover, an end cap ring is provided at the lower end of the top cover, an end cap inner seat is provided inside the end cap ring, an upper sealing ring and a lower sealing ring are provided on the end cap inner seat, the probe passes through the sealing end cap and is placed inside the pipe to be tested, and the end cap inner seat extends into the pipe, so that the upper and lower sealing rings of the end cap inner seat are tightly fitted with the inner wall of the pipe to be tested to form a sealed space, which plays the role of double sealing, heat insulation and fixing the pipe; the end cap ring is tightly fitted with the sealing groove at the work station mouth to achieve sealing and heat insulation; the outer layer of the sealing end cap is provided with an insulation layer, and the sealing end cap can be insulated by the insulation layer.

[0011] Furthermore, the liquid inside the pipe to be tested is distilled water or thermal oil; an insulation layer is provided on the outside of the constant temperature water tank, and the constant temperature water tank can be thermally insulated by the insulation layer.

[0012] Furthermore, a comparative test method for thermal conductivity of floor heating pipes includes the following steps: Step 1: Cut equal lengths of the pipes to be compared according to the same specifications and dimensions. Seal the lower end of the pipes with a heat-insulating pipe plug. Add the same amount of liquid (distilled water or heat-conducting oil) into the upper end of the pipes. Seal the sealing end cap on the upper end of the pipes. Insert the probe into the pipe and immerse it in the liquid to prepare the pipe samples to be compared. Step 2: Heat the water in the constant temperature water tank to the required temperature and wait until the water temperature in the constant temperature water tank is constant; Step 3: Use the input keyboard to pre-set the temperature T as the end point temperature of the liquid inside the pipe to be tested, which will be displayed on the temperature display; Step 4: Place the pipe samples to be compared in an environment with the same temperature for state adjustment. After the initial temperature of the liquid inside the pipes is the same, quickly place the two pipes to be compared in the corresponding workstations. The initial temperature T1 of the liquid inside the pipes is transmitted to the temperature measurement module through the probe and displayed on the temperature display. Step 5: When the sealing end cap on the upper end of the pipe to be tested triggers the left and right contacts, the timing module starts timing; Step 6: As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to continue to rise. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time taken for the liquid in the pipe to go from the initial temperature T1 to the end temperature T, and displays it on the time display; Step 7: Use the temperature measurement and display timer corresponding to station 1 to record the time t1 taken by the liquid in the pipe at station 1 from the initial temperature T1 to the final temperature T. Use the temperature measurement and display timer corresponding to station 2 to record the time t2 taken by the liquid in the pipe at station 2 from the initial temperature T1 to the final temperature T. Compare the thermal conductivity of the pipes at stations 1 and 2: R is the comparative evaluation value of thermal conductivity; Indicates the time (s) taken by the liquid inside the pipe at station 1 to change from the initial temperature T1 to the final temperature T; Indicates the time (s) taken by the liquid inside the pipe at station 2 to reach the final temperature T from the initial temperature T1; When R>1, the thermal conductivity of the pipe at station 1 is better than that of the pipe at station 2; When R<1, the thermal conductivity of the pipe at station 2 is better than that of the pipe at station 1; When R=1, the thermal conductivity of the pipe at station 1 is the same as that of the pipe at station 2; The above method can be used to compare and evaluate the thermal conductivity of pipes at different workstations.

[0013] Furthermore, a comparative test and evaluation method for thermal conductivity of floor heating pipes includes the following steps: Step 1: Obtain comparison samples: Sample the floor heating pipes of the current production batch according to the preset sampling plan, and obtain n number of sampling samples, where n represents the number of sampling samples; the sampling samples are recorded as N i ,i=1,2,…n;According to the preset quality requirements, determine the preset standard sample of floor heating pipes and record it as N s ; Step 2: Comparative test of thermal conductivity of floor heating pipe samples: S1: Take the sample N of the pipes from the current production batch to be compared. i and preset standard sample N s Cut equal lengths according to the same specifications and sizes, seal the lower end of the pipe with a pipe plug with insulation, add the same mass of the same liquid into the pipe from the upper end of the pipe. The liquid can be distilled water or heat-conducting oil, seal the sealing end cap on the upper end of the pipe, extend the probe into the pipe and immerse it in the liquid, and prepare sampling samples N respectively. i and preset standard sample N s The pipe sample to be tested; S2: Heat the water in the constant temperature water tank to the required temperature and wait until the water temperature in the constant temperature water tank is constant; S3: Preset the temperature T through the input keyboard as the end point temperature of the liquid inside the pipe to be tested, which is displayed on the temperature display; S4: Place the pipe samples to be compared in an environment with the same temperature for state adjustment. After the initial temperature of the liquid in the pipe is the same, quickly place the two pipes to be compared in the corresponding stations. i The pipe sample to be tested is placed in station 1, and the preset standard sample N s The pipe sample to be tested is placed in station 2; the initial temperature T1 of the liquid inside the pipe is transmitted to the temperature measurement module through the probe and displayed on the temperature display; S5: When the sealing end cap on the upper end of the pipe to be tested triggers the left and right contacts, the timing unit starts timing; S6: As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to rise continuously. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time taken by the liquid inside the pipe to reach the end temperature T from the initial temperature T1, and displays it on the time display. The sampling sample N of station 1 is recorded through the time displays corresponding to station 1 and station 2 respectively. i The time t taken by the liquid in the pipe to change from the initial temperature T1 to the final temperature T 1i And station 2 preset standard sample N s The time t taken by the liquid in the pipe to change from the initial temperature T1 to the final temperature T 2i ; Step 3: Comparative evaluation of thermal conductivity of floor heating pipe samples: Calculate R by comparing the evaluation formula i , where R i Indicates the comparative evaluation value of thermal conductivity of the i-th sample, t 1i Indicates the sample N of station 1 for the comparison test of the i-th samplei The time (s) it takes for the liquid inside the pipe to reach the final temperature T from the initial temperature T1; t 2i Indicates the preset standard sample N of station 2 for the comparison test of the i-th sampling sample s The time (s) it takes for the liquid inside the pipe to reach the final temperature T from the initial temperature T1; By R i Comparative evaluation of thermal conductivity for sample N i With the preset standard sample N s The thermal conductivity of the following are compared and evaluated: When R i >1, sample N i The thermal conductivity is better than the preset standard sample N s thermal conductivity; When R i When <1, preset standard sample N s The thermal conductivity is better than that of the sample N i thermal conductivity; When R i =1, the sampling sample N i The thermal conductivity of the preset standard sample N s The thermal conductivity is the same; Step 4: Stability evaluation of thermal conductivity of floor heating pipe samples: Calculate s according to the following analytical formula i : where s i R represents the thermal conductivity deviation evaluation value of the i-th sample; i It represents the comparative evaluation value of thermal conductivity of the i-th sample; By thermal conductivity deviation value s i For the sample N i With the preset standard sample N s The degree of deviation of thermal conductivity is analyzed and compared with the pre-set threshold value s0 of thermal conductivity deviation evaluation value: When s i When ≤s0, the sampling sample N i With the preset standard sample N s The degree of thermal conductivity deviation meets the pre-set requirements; When s i >s0, sample N i With the preset standard sample N s The degree of thermal conductivity deviation does not meet the pre-set requirements; Step 5: Comprehensively evaluate the thermal conductivity of the current production batch of floor heating pipes and form a quality inspection report: According to the following analysis formula, R i The number of times M is greater than or equal to 1: Where M is the thermal conductivity comparison evaluation factor, which means R i ≥1 times; n represents the number of samples; R i It represents the comparative evaluation value of thermal conductivity of the i-th sample; According to the following analysis formula, statistics s i The number of times ≥s0 K: Where K is the thermal conductivity deviation evaluation factor, which means s i ≥s0 times; n represents the number of sampling samples; s i represents the deviation evaluation value of the thermal conductivity of the i-th sample; s0 represents the threshold requirement of the pre-set thermal conductivity deviation evaluation value; By comparing the thermal conductivity comparison evaluation factor M and the thermal conductivity deviation evaluation factor K with the pre-set threshold requirements M0 and K0 respectively, a comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipe products is conducted: When M≥M0 and K≤K0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes meets the pre-set requirements and is determined to be qualified; When M≥M0 and K>K0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes does not meet the pre-set requirements and is judged to be unqualified; When M<M0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes does not meet the pre-set requirements and is judged to be unqualified; Wherein, M0 represents the threshold requirement of the pre-set thermal conductivity comparison evaluation factor; K0 represents the threshold requirement of the pre-set thermal conductivity deviation evaluation factor.

[0014] The beneficial effects of the present invention are as follows: 1. The thermal conductivity of floor heating pipes can be simply and quickly compared and tested by this device, especially the thermal conductivity comparison of multi-layer composite pipes made of different materials. The comparative test can be directly carried out by preparing pipe samples, and the comparison is intuitive, efficient, short in cycle, and low in cost. 2. The thermal conductivity of floor heating pipes can be comprehensively evaluated quickly and comprehensively in many aspects by this device. The thermal conductivity of different batches of floor heating pipes can be directly compared with the standard samples during the production process, and the fluctuation of the thermal conductivity of different batches of floor heating pipes can also be monitored. Quality inspection and evaluation are carried out from multiple dimensions, including the comparison of the thermal conductivity of floor heating pipes and the degree of deviation of thermal conductivity, thereby improving the quality assessment system of the thermal conductivity of floor heating pipes, which is conducive to better ensuring the quality of floor heating pipe products. 3. The present invention judges whether the thermal conductivity of floor heating pipe products is qualified and generates a quality inspection report through the comparison and evaluation of the thermal conductivity of floor heating pipes, so that enterprises can find problems existing in the production process of floor heating pipes, and provide a basis for enterprises to evaluate and improve production processes and optimize product designs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a front view of the testing device of the present invention; Figure 2 is a top view of the testing device of the present invention; Figure 3 It is a structural schematic diagram of placing the pipe to be tested into the testing device of the present invention; Figure 4 It is a schematic structural diagram of the sealing end cap of the present invention; Figure 5 yes Figure 4 The cross-sectional view of the AA surface; Figure 6 It is a structural block diagram of the temperature measurement and display timer of the test device of the present invention. DETAILED DESCRIPTION

[0016] In order to better understand the purpose, function and specific design scheme of the present invention, the following is a further detailed description of the thermal conductivity comparison test device, test method and evaluation method of the floor heating pipe of the present invention in conjunction with the accompanying drawings.

[0017] like Figure 1-Figure 3As shown, the thermal conductivity comparison test device of the floor heating pipe of the present invention includes a constant temperature water tank 1, which is filled with water. A tank cover 2 is provided on the top of the constant temperature water tank 1, and a constant temperature heater 3 is provided at the bottom of the constant temperature water tank 1. The water in the constant temperature water tank 1 can be heated by the constant temperature heater 3 to ensure that the water in the constant temperature water tank 1 is always within the required water temperature range. The tank cover 2 is provided with a first workstation opening 21 and a second workstation opening 22, both of which are connected to the interior of the constant temperature water tank 1. The first workstation opening 21 is provided with a left contact 25 and a right contact 26, and the left contact 25 and the right contact 26 are connected to their corresponding temperature measurement and display timers 4 through a circuit. The second workstation opening 22 is provided with a left contact 27 and a right contact 28, and the left contact 27 and the right contact 28 are connected to their corresponding temperature measurement and display timers 5 through a circuit. Two temperature measurement and display timers are provided on the front surface of the constant temperature water tank 1.

[0018] The bottom of the pipe to be tested 6 is closed, liquid is filled inside, and a sealing end cap 7 is provided on the upper end. The liquid inside the pipe to be tested 6 is distilled water or thermal oil. The pipe to be tested is extended into the constant temperature water tank 1 through the work station opening, and the lower end of the pipe to be tested 6 is immersed in the water of the constant temperature water tank 1. The upper end of the pipe to be tested 6 is fixed at the work station opening through the sealing end cap 7. A probe 76 is provided in the middle of the sealing end cap 7. One end of the probe 76 is extended into the pipe to be tested and immersed in distilled water or thermal oil. The other end of the probe 76 is connected to the corresponding temperature measurement display timer through a circuit.

[0019] like Figure 6 As shown, the two temperature measuring and display timers have the same structure. For the convenience of description, one of the temperature measuring and display timers is taken as an example. The temperature measuring and display timer includes a shell and a circuit board arranged in the shell. The circuit board is provided with a microprocessor, a temperature measuring module, a timing module, an input keyboard, a time display and a temperature display. The temperature measuring module, the timing module, the input keyboard, the time display and the temperature display are electrically connected to the microprocessor through wires respectively. The input keyboard, the time display and the temperature display are arranged on the outer surface of the shell. The temperature T can be pre-set through the input keyboard as the end temperature of the liquid inside the pipe to be measured.

[0020] The timing module is connected to the left and right contacts through a circuit. After the pipe to be tested is placed in the work station, the sealing end cap at its upper end triggers the left and right contacts, and the timing module starts timing.

[0021] The temperature measurement module is connected to the probe through a circuit, and the probe measures the initial temperature T1 of the liquid inside the pipe. As time increases, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to continue to rise. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, that is, the time taken for the liquid in the pipe to reach the end temperature T from the initial temperature T1.

[0022] The temperature display is used to display the preset end point temperature T and the initial temperature T1 of the liquid inside the pipe, and the time display is used to display the time t used by the liquid inside the pipe to change from the initial temperature T1 to the end point temperature T.

[0023] A reset button is also provided on the circuit board. The reset button is exposed outside the shell and is electrically connected to the microprocessor through a wire. After completing the recording of the initial temperature T1, end temperature T and time t of the liquid in the tube, take out the tube and click the reset button to clear the data display and reset the temperature display timer to wait for a new test.

[0024] The circuit board is also provided with a memory and a communication unit, which are electrically connected to the microprocessor through wires respectively. The memory is used to store the signals processed by the microprocessor. The records in the memory can be retrieved through the input keyboard and displayed on the display. The communication unit can connect and send the signals processed by the microprocessor to external devices.

[0025] A power supply is also provided in the housing. The power supply is a lithium battery. The power supply is connected to the microprocessor and provides power to each unit on the circuit board through the microprocessor.

[0026] like Figure 1-Figure 3 As shown, the cover 2 is provided with sealing grooves 23 and 24 near the two workstation openings. After the test pipe 6 passes through the workstation openings and enters the constant temperature water tank 1, the sealing end cap 7 on the upper end of the test pipe 6 tightly fits into the sealing grooves. The constant temperature water tank 1 is provided with an insulation layer 11 on the outside to keep the constant temperature water tank 1 warm.

[0027] like Figure 4 and Figure 5 As shown, the sealing end cap 7 includes a top cover 71, an end cap ring 72 is provided at the lower end of the top cover 71, an end cap inner seat 75 is provided inside the end cap ring 72, an upper sealing ring 73 and a lower sealing ring 74 are provided on the end cap inner seat 75, a probe 76 passes through the sealing end cap 7 and is placed inside the pipe 6 to be tested, and the end cap inner seat 75 extends into the pipe, so that the upper and lower sealing rings of the end cap inner seat 75 are tightly fitted with the inner wall of the pipe to be tested to form a double seal, heat insulation and fix the pipe, and the end cap ring 72 is tightly fitted with the sealing groove at the work station mouth to achieve sealing and heat insulation.

[0028] The comparative test method for thermal conductivity of floor heating pipes includes the following steps: Step 1: Cut equal lengths of the pipes to be compared according to the same specifications and dimensions. Seal the lower end of the pipes with a heat-insulating pipe plug. Add the same amount of liquid (distilled water or heat-conducting oil) into the upper end of the pipes. Seal the sealing end cap on the upper end of the pipes. Insert the probe into the pipe and immerse it in the liquid to prepare the pipe samples to be compared. Step 2: Heat the water in the constant temperature water tank to the required temperature and wait until the water temperature in the constant temperature water tank is constant; Step 3: Use the input keyboard to pre-set the temperature T as the end point temperature of the liquid inside the pipe to be tested, which will be displayed on the temperature display; Step 4: Place the pipe samples to be compared in an environment with the same temperature for state adjustment. After the initial temperature of the liquid inside the pipes is the same, quickly place the two pipes to be compared in the corresponding workstations. The initial temperature T1 of the liquid inside the pipes is transmitted to the temperature measurement module through the probe and displayed on the temperature display. Step 5: When the sealing end cap on the upper end of the pipe to be tested triggers the left and right contacts, the timing module starts timing; Step 6: As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to continue to rise. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time taken for the liquid in the pipe to go from the initial temperature T1 to the end temperature T, and displays it on the time display; Step 7: Use the temperature measurement and display timer corresponding to station 1 to record the time t1 taken by the liquid in the pipe at station 1 from the initial temperature T1 to the final temperature T. Use the temperature measurement and display timer corresponding to station 2 to record the time t2 taken by the liquid in the pipe at station 2 from the initial temperature T1 to the final temperature T. Compare the thermal conductivity of the pipes at stations 1 and 2: R is the comparative evaluation value of thermal conductivity; Indicates the time (s) taken by the liquid inside the pipe at station 1 to change from the initial temperature T1 to the final temperature T; Indicates the time (s) taken by the liquid inside the pipe at station 2 to reach the final temperature T from the initial temperature T1; When R>1, the thermal conductivity of the pipe at station 1 is better than that of the pipe at station 2; When R<1, the thermal conductivity of the pipe at station 2 is better than that of the pipe at station 1; When R=1, the thermal conductivity of the pipe at station 1 is the same as that of the pipe at station 2; The above method can be used to compare and evaluate the thermal conductivity of pipes at different workstations.

[0029] The evaluation method for comparative testing of thermal conductivity of floor heating pipes includes the following steps: Step 1: Obtain comparison samples: Sample the floor heating pipes of the current production batch according to the preset sampling plan, and obtain n number of sampling samples, where n represents the number of sampling samples; the sampling samples are recorded as N i ,i=1,2,…n;According to the preset quality requirements, determine the preset standard sample of floor heating pipes and record it as N s ; Step 2: Comparative test of thermal conductivity of floor heating pipe samples: S1: Take the sample N of the pipes from the current production batch to be compared. i and preset standard sample N s Cut equal lengths according to the same specifications and sizes, seal the lower end of the pipe with a pipe plug with insulation, add the same mass of the same liquid into the pipe from the upper end of the pipe. The liquid can be distilled water or heat-conducting oil, seal the sealing end cap on the upper end of the pipe, extend the probe into the pipe and immerse it in the liquid, and prepare sampling samples N respectively. i and preset standard sample N s The pipe sample to be tested; S2: Heat the water in the constant temperature water tank to the required temperature and wait until the water temperature in the constant temperature water tank is constant; S3: Preset the temperature T through the input keyboard as the end point temperature of the liquid inside the pipe to be tested, which is displayed on the temperature display; S4: Place the pipe samples to be compared in an environment with the same temperature for state adjustment. After the initial temperature of the liquid in the pipe is the same, quickly place the two pipes to be compared in the corresponding stations. i The pipe sample to be tested is placed in station 1, and the preset standard sample N s The pipe sample to be tested is placed in station 2; the initial temperature T1 of the liquid inside the pipe is transmitted to the temperature measurement module through the probe and displayed on the temperature display; S5: When the sealing end cap on the upper end of the pipe to be tested triggers the left and right contacts, the timing unit starts timing; S6: As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to rise continuously. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time taken by the liquid inside the pipe to reach the end temperature T from the initial temperature T1, and displays it on the time display. The sampling sample N of station 1 is recorded through the time displays corresponding to station 1 and station 2 respectively. i The time t taken by the liquid in the pipe to change from the initial temperature T1 to the final temperature T 1i And station 2 preset standard sample N sThe time t taken by the liquid in the pipe to change from the initial temperature T1 to the final temperature T 2i ; Step 3: Comparative evaluation of thermal conductivity of floor heating pipe samples: Calculate R by comparing the evaluation formula i , where R i Indicates the comparative evaluation value of thermal conductivity of the i-th sample, t 1i Indicates the sample N of station 1 for the comparison test of the i-th sample i The time (s) it takes for the liquid inside the pipe to reach the final temperature T from the initial temperature T1; t 2i Indicates the preset standard sample N of station 2 for the comparison test of the i-th sampling sample s The time (s) it takes for the liquid inside the pipe to reach the final temperature T from the initial temperature T1; By R i Comparative evaluation of thermal conductivity for sample N i With the preset standard sample N s The thermal conductivity of the products is compared and evaluated respectively: When R i >1, sample N i The thermal conductivity is better than the preset standard sample N s thermal conductivity; When R i When <1, preset standard sample N s The thermal conductivity is better than that of the sample N i thermal conductivity; When R i =1, the sampling sample N i The thermal conductivity of the preset standard sample N s The thermal conductivity is the same; Step 4: Stability evaluation of thermal conductivity of floor heating pipe samples: Calculate s according to the following analytical formula i : where s i R represents the thermal conductivity deviation evaluation value of the i-th sample; i It represents the comparative evaluation value of thermal conductivity of the i-th sample; By thermal conductivity deviation value s i For the sample N i With the preset standard sample N s The degree of deviation of thermal conductivity is analyzed and compared with the pre-set threshold value s0 of thermal conductivity deviation evaluation value: When si When ≤s0, the sampling sample N i With the preset standard sample N s The degree of thermal conductivity deviation meets the pre-set requirements; When s i >s0, sample N i With the preset standard sample N s The degree of thermal conductivity deviation does not meet the pre-set requirements; Step 5: Comprehensively evaluate the thermal conductivity of the current production batch of floor heating pipes and form a quality inspection report: According to the following analysis formula, R i The number of times M is greater than or equal to 1: Where M is the thermal conductivity comparison evaluation factor, which means R i ≥1 times; n represents the number of samples; R i It represents the comparative evaluation value of thermal conductivity of the i-th sample; According to the following analysis formula, statistics s i The number of times ≥s0 K: Where K is the thermal conductivity deviation evaluation factor, which means s i ≥s0 times; n represents the number of sampling samples; s i represents the deviation evaluation value of the thermal conductivity of the i-th sample; s0 represents the threshold requirement of the pre-set thermal conductivity deviation evaluation value; By comparing the thermal conductivity comparison evaluation factor M and the thermal conductivity deviation evaluation factor K with the pre-set threshold requirements M0 and K0 respectively, a comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipe products is conducted: When M≥M0 and K≤K0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes meets the pre-set requirements and is determined to be qualified; When M≥M0 and K>K0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes does not meet the pre-set requirements and is judged to be unqualified; When M<M0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes does not meet the pre-set requirements and is judged to be unqualified; Wherein, M0 represents the threshold requirement of the pre-set thermal conductivity comparison evaluation factor; K0 represents the threshold requirement of the pre-set thermal conductivity deviation evaluation factor.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A device for comparing the thermal conductivity of floor heating pipes, comprising a constant temperature water tank, characterized in that: The constant temperature water tank is filled with water, a tank cover is provided on the top of the constant temperature water tank, and a constant temperature heater is provided at the bottom of the constant temperature water tank. The water in the constant temperature water tank can be heated by the constant temperature heater to ensure that the water in the constant temperature water tank is always within the required water temperature range; two work station openings are provided on the tank cover, and the two work station openings are connected to the interior of the constant temperature water tank, and both work station openings are provided with left and right contacts, and the left and right contacts are connected to the temperature measurement display timer through lines; the bottom of the pipe to be tested is closed, the interior is filled with liquid, and the upper end is provided with a sealing end cap, the pipe to be tested is extended into the constant temperature water tank through the work station opening, the lower end of the pipe to be tested is immersed in the water in the constant temperature water tank, the upper end of the pipe to be tested is fixed at the work station opening through the sealing end cap, and a probe is provided in the middle of the sealing end cap, one end of the probe is extended into the pipe to be tested and immersed in the liquid in the pipe to be tested, and the other end of the probe is connected to the temperature measurement display timer through a line.

2. The device for comparing thermal conductivity of floor heating pipes according to claim 1, characterized in that: The temperature measurement and display timer includes a housing and a circuit board disposed within the housing. The circuit board is provided with a microprocessor, a temperature measurement module, a timing module, an input keyboard, a time display, and a temperature display. The temperature measurement module, timing module, input keyboard, time display, and temperature display are electrically connected to the microprocessor via wires. The input keyboard, time display, and temperature display are disposed on the outer surface of the housing. The temperature T can be pre-set via the input keyboard as the endpoint temperature of the liquid inside the pipe to be measured. The timing module is connected to the left and right contacts through a circuit. When the pipe to be tested is placed in the work station, the sealing end cap on its upper end triggers the left and right contacts, and the timing module starts timing. The temperature measurement module is connected to the probe via a circuit. The probe can measure the initial temperature T1 of the liquid inside the pipe. As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to continue to rise. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time it takes for the liquid inside the pipe to go from the initial temperature T1 to the end temperature T. The temperature display is used to display the preset end point temperature T and the initial temperature T1 of the liquid inside the pipe; the time display is used to display the time t used by the liquid inside the pipe to change from the initial temperature T1 to the end point temperature T.

3. The device for comparing thermal conductivity of floor heating pipes according to claim 2, characterized in that: A reset button is also provided on the circuit board. The reset button is exposed outside the shell and is electrically connected to the microprocessor through a wire. After completing the recording of the initial temperature T1, end temperature T and time t of the liquid inside the pipe, take out the pipe and click the reset button to clear the data display and reset the temperature display timer to wait for a new test.

4. The device for comparing thermal conductivity of floor heating pipes according to claim 2, characterized in that: The circuit board is also provided with a memory and a communication unit, which are electrically connected to the microprocessor through wires respectively. The memory is used to store the signals processed by the microprocessor. The records in the memory can be retrieved through the input keyboard and displayed on the display; the communication unit can connect and send the signals processed by the microprocessor to an external device.

5. The device for comparing thermal conductivity of floor heating pipes according to claim 2, characterized in that: A power supply is also provided in the housing. The power supply is a lithium battery. The power supply is connected to the microprocessor and provides power to each unit on the circuit board through the microprocessor.

6. The device for comparing thermal conductivity of floor heating pipes according to claim 1, characterized in that: The box cover is provided with sealing grooves near the two workstation openings. After the pipe to be tested passes through the workstation opening and enters the constant temperature water tank, the sealing end cap on the upper end of the pipe to be tested fits tightly with the sealing groove.

7. The device for comparing thermal conductivity of floor heating pipes according to claim 6, characterized in that: The sealing end cap includes a top cover, an end cap ring is provided at the lower end of the top cover, an end cap inner seat is provided inside the end cap ring, an upper sealing ring and a lower sealing ring are provided on the end cap inner seat, the probe passes through the sealing end cap and is placed inside the pipe to be tested, and the end cap inner seat extends into the pipe, so that the upper and lower sealing rings of the end cap inner seat are tightly fitted with the inner wall of the pipe to be tested to form a sealed space, which plays the role of double sealing, heat insulation and fixing the pipe; the end cap ring is tightly fitted with the sealing groove at the work station mouth to achieve sealing and heat insulation; the outer layer of the sealing end cap is provided with an insulation layer, and the sealing end cap can be insulated by the insulation layer.

8. The device for comparing thermal conductivity of floor heating pipes according to claim 1, characterized in that: The liquid inside the pipe to be tested is distilled water or thermal oil; the outside of the constant temperature water tank is provided with a thermal insulation layer, which can be used to insulate the constant temperature water tank.

9. A method for comparative testing of thermal conductivity of floor heating pipes, using the comparative testing device according to any one of claims 1 to 8, characterized in that: The comparative test method includes the following steps: Step 1: Cut equal lengths of the pipes to be compared according to the same specifications and dimensions. Seal the lower end of the pipes with a heat-insulating pipe plug. Add the same amount of liquid (distilled water or heat-conducting oil) into the upper end of the pipes. Seal the sealing end cap on the upper end of the pipes. Insert the probe into the pipe and immerse it in the liquid to prepare the pipe samples to be compared. Step 2: Heat the water in the constant temperature water tank to the required temperature and wait until the water temperature in the constant temperature water tank is constant; Step 3: Use the input keyboard to pre-set the temperature T as the end point temperature of the liquid inside the pipe to be tested, which will be displayed on the temperature display; Step 4: Place the pipe samples to be compared in an environment with the same temperature for state adjustment. After the initial temperature of the liquid inside the pipes is the same, quickly place the two pipes to be compared in the corresponding workstations. The initial temperature T1 of the liquid inside the pipes is transmitted to the temperature measurement module through the probe and displayed on the temperature display. Step 5: When the sealing end cap on the upper end of the pipe to be tested triggers the left and right contacts, the timing module starts timing; Step 6: As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to continue to rise. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time taken for the liquid in the pipe to go from the initial temperature T1 to the end temperature T, and displays it on the time display; Step 7: Use the temperature measurement and display timer corresponding to station 1 to record the time t1 taken by the liquid in the pipe at station 1 from the initial temperature T1 to the final temperature T. Use the temperature measurement and display timer corresponding to station 2 to record the time t2 taken by the liquid in the pipe at station 2 from the initial temperature T1 to the final temperature T. Compare the thermal conductivity of the pipes at stations 1 and 2: R is the comparative evaluation value of thermal conductivity; Indicates the time (s) taken by the liquid inside the pipe at station 1 to change from the initial temperature T1 to the final temperature T; Indicates the time (s) taken by the liquid inside the pipe at station 2 to reach the final temperature T from the initial temperature T1; When R>1, the thermal conductivity of the pipe at station 1 is better than that of the pipe at station 2; When R<1, the thermal conductivity of the pipe at station 2 is better than that of the pipe at station 1; When R=1, the thermal conductivity of the pipe at station 1 is the same as that of the pipe at station 2; The above method can be used to compare and evaluate the thermal conductivity of pipes at different workstations.

10. A method for evaluating the thermal conductivity of floor heating pipes by comparative testing, using the comparative testing device according to any one of claims 1 to 8, characterized in that: The comparative test evaluation method includes the following steps: Step 1: Obtain comparison samples: Sample the floor heating pipes of the current production batch according to the preset sampling plan, and obtain n number of sampling samples, where n represents the number of sampling samples; the sampling samples are recorded as N i ,i=1,2,…n;According to the preset quality requirements, determine the preset standard sample of floor heating pipes and record it as N s ; Step 2: Comparative test of thermal conductivity of floor heating pipe samples: S1: Take the sample N of the pipes from the current production batch to be compared. i and preset standard sample N s Cut equal lengths according to the same specifications and sizes, seal the lower end of the pipe with a pipe plug with insulation, add the same mass of the same liquid into the pipe from the upper end of the pipe. The liquid can be distilled water or heat-conducting oil, seal the sealing end cap on the upper end of the pipe, extend the probe into the pipe and immerse it in the liquid, and prepare sampling samples N respectively. i and preset standard sample N s The pipe sample to be tested; S2: Heat the water in the constant temperature water tank to the required temperature and wait until the water temperature in the constant temperature water tank is constant; S3: Preset the temperature T through the input keyboard as the end point temperature of the liquid inside the pipe to be tested, which is displayed on the temperature display; S4: Place the pipe samples to be compared in an environment with the same temperature for state adjustment. After the initial temperature of the liquid in the pipe is the same, quickly place the two pipes to be compared in the corresponding stations. i The pipe sample to be tested is placed in station 1, and the preset standard sample N s The pipe sample to be tested is placed in station 2; the initial temperature T1 of the liquid inside the pipe is transmitted to the temperature measurement module through the probe and displayed on the temperature display; S5: When the sealing end cap on the upper end of the pipe to be tested triggers the left and right contacts, the timing unit starts timing; S6: As time goes by, the constant temperature water outside the pipe continuously transfers heat to the liquid inside the pipe, causing the temperature of the liquid inside the pipe to rise continuously. When the temperature of the liquid inside the pipe reaches the preset temperature T, the timing module stops timing and records the time t, which is the time taken by the liquid inside the pipe to reach the end temperature T from the initial temperature T1, and displays it on the time display. The sampling sample N of station 1 is recorded through the time displays corresponding to station 1 and station 2 respectively. i The time t taken by the liquid in the pipe to change from the initial temperature T1 to the final temperature T 1i And station 2 preset standard sample N s The time t taken by the liquid in the pipe to change from the initial temperature T1 to the final temperature T 2i ; Step 3: Comparative evaluation of thermal conductivity of floor heating pipe samples: Calculate R by comparing the evaluation formula i , where R i Indicates the comparative evaluation value of thermal conductivity of the i-th sample, t 1i Indicates the sample N of station 1 for the comparison test of the i-th sample i The time (s) it takes for the liquid inside the pipe to reach the final temperature T from the initial temperature T1; t 2i Indicates the preset standard sample N of station 2 for the comparison test of the i-th sampling sample s The time (s) it takes for the liquid inside the pipe to reach the final temperature T from the initial temperature T1; By R i Comparative evaluation of thermal conductivity for sample N i With the preset standard sample N s The thermal conductivity of the products is compared and evaluated respectively: When R i >1, sample N i The thermal conductivity is better than the preset standard sample N s thermal conductivity; When R i When <1, preset standard sample N s The thermal conductivity is better than that of the sample N i thermal conductivity; When R i =1, the sampling sample N i The thermal conductivity of the preset standard sample N s The thermal conductivity is the same; Step 4: Stability evaluation of thermal conductivity of floor heating pipe samples: Calculate s according to the following analytical formula i : where s i R represents the thermal conductivity deviation evaluation value of the i-th sample; i It represents the comparative evaluation value of thermal conductivity of the i-th sample; By thermal conductivity deviation value s i For the sample N i With the preset standard sample N s The degree of deviation of thermal conductivity is analyzed and compared with the pre-set threshold value s0 of thermal conductivity deviation evaluation value: When s i When ≤s0, the sampling sample N i With the preset standard sample N s The degree of thermal conductivity deviation meets the pre-set requirements; When s i >s0, the sampling sample N i With the preset standard sample N s The degree of thermal conductivity deviation does not meet the pre-set requirements; Step 5: Comprehensively evaluate the thermal conductivity of the current production batch of floor heating pipes and form a quality inspection report: According to the following analysis formula, R i The number of times M is greater than or equal to 1: Where M is the thermal conductivity comparison evaluation factor, which means R i ≥1; n represents the number of samples; R i It represents the comparative evaluation value of thermal conductivity of the i-th sample; According to the following analysis formula, statistics s i The number of times ≥s0 K: Where K is the thermal conductivity deviation evaluation factor, which means s i ≥s0 times; n represents the number of sampling samples; s i represents the deviation evaluation value of the thermal conductivity of the i-th sample; s0 represents the threshold requirement of the pre-set thermal conductivity deviation evaluation value; By comparing the thermal conductivity comparison evaluation factor M and the thermal conductivity deviation evaluation factor K with the pre-set threshold requirements M0 and K0 respectively, a comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipe products is conducted: When M≥M0 and K≤K0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes meets the pre-set requirements and is determined to be qualified; When M≥M0 and K>K0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes does not meet the pre-set requirements and is judged to be unqualified; When M<M0, the comprehensive evaluation of the thermal conductivity of the current production batch of floor heating pipes does not meet the pre-set requirements and is judged to be unqualified; Wherein, M0 represents the threshold requirement of the pre-set thermal conductivity comparison evaluation factor; K0 represents the threshold requirement of the pre-set thermal conductivity deviation evaluation factor.

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