An apparatus for determining asphalt volatile loss

Abstract

The utility model discloses an asphalt volatile loss determination device relates to asphalt performance detection equipment technical field, aims at solving the low temperature control precision of existing equipment, the problem of cumbersome operation, poor safety and the lack of structural stability. The device includes heating temperature control assembly, nitrogen preheating assembly, sample lifting assembly, open and close subassembly and control assembly, heating temperature control assembly contains upper and lower heating aluminum base body, can form sealed heating cavity, and is equipped with the direct monitoring sample temperature of through -type sample temperature measurement thermocouple, nitrogen preheating assembly preheats nitrogen through the coil that winds in lower heating aluminum base body, sample lifting assembly and open and close subassembly realize sample dish automatic lifting and heating cavity automatic open and close respectively, and control assembly overall planning controls each component, realizes the automation operation. The device can avoid cold nitrogen temperature disturbance, accurate temperature control, improves operating efficiency and safety, satisfies the efficient accurate detection demand of asphalt volatile loss.

Description

Technical Field

[0001] This utility model relates to the technical field of asphalt performance testing equipment, specifically a special testing device for determining the amount of volatilization loss of asphalt at a specific temperature. Background Technology

[0002] In the production, construction, and quality testing of asphalt, the volatilization loss of asphalt is a key indicator for evaluating its high-temperature stability and durability. Existing equipment for determining asphalt volatilization loss has the following technical shortcomings: First, when nitrogen is directly introduced into the heating chamber as a protective and purging gas, the low temperature can easily disrupt the temperature balance within the chamber, leading to an unstable test environment and affecting the accuracy of the test data. Second, the sample temperature is indirectly inferred from the heated substrate, making it impossible to directly obtain the real-time internal temperature of the sample, hindering precise control of the heating rate, and easily causing uneven heating of the sample. Third, the opening and closing of the upper heating component often uses a manual snap-fit ​​structure, which is cumbersome to operate and its sealing is easily affected by human error. Furthermore, the placement and removal of the sample dish requires manual insertion into the heating chamber, which is not only inefficient but also poses a risk of burns from high temperatures. Fourth, the fixing method of the nitrogen conduction component lacks stability and is prone to displacement during the test, further reducing the reliability of the test data. To address the aforementioned issues, there is currently no structurally sound and fully functional solution. There is an urgent need to design an asphalt volatilization loss measuring device that can achieve nitrogen preheating, direct sample temperature measurement, automatic opening and closing, and safe lifting and lowering, in order to meet the requirements of high-precision and high-efficiency testing. Summary of the Invention

[0003] The purpose of this utility model is to provide a device for measuring asphalt volatilization loss, solving the problems of low temperature control accuracy, cumbersome operation, poor safety, and insufficient structural stability of existing equipment, and achieving efficient and accurate detection of asphalt volatilization loss. The asphalt volatilization loss measuring device includes a heating and temperature control component, a nitrogen preheating component, a sample lifting component, an opening and closing component, and a control component.

[0004] The heating and temperature control assembly includes upper and lower heating aluminum substrates. The lower heating aluminum substrate is made of high thermal conductivity aluminum alloy. Two lower heating rod mounting holes are vertically oriented inside the lower heating aluminum substrate, each fitted with a lower heating rod to provide a stable heat source. A lower substrate temperature measuring hole is also provided inside the lower heating aluminum substrate, housing a lower substrate temperature measuring thermocouple for real-time temperature monitoring. Spiral grooves are machined on the outer circumferential surface of the lower heating aluminum substrate to secure the nitrogen preheating assembly. The lower heating aluminum substrate is wrapped with ceramic fiber to reduce heat loss and prevent operators from contacting high-temperature components. The upper heating aluminum substrate is sized to match the lower heating aluminum substrate and is distributed vertically. When the upper and lower heating aluminum substrates are closed, they form a sealed heating cavity, providing a stable heating environment for the asphalt sample. The upper heating aluminum substrate has two vertically oriented mounting holes for each heating rod, which is fitted with one heating rod to supplement the heat source and ensure uniform temperature within the heating cavity. The upper heating aluminum substrate also has two temperature measuring holes. One hole houses a thermocouple for monitoring the temperature of the upper heating aluminum substrate, while the other hole penetrates the upper and lower surfaces of the upper heating aluminum substrate and houses a thermocouple for the sample. The lower end of the thermocouple can extend into the sample within the heating cavity to directly monitor the sample's heating rate.

[0005] The nitrogen preheating assembly includes a nitrogen preheating coil and a gas flow meter. The nitrogen preheating coil is made of stainless steel and is wound and fixed on the outer spiral groove of the lower heating aluminum substrate, so that the coil is in close contact with the lower heating aluminum substrate to ensure efficient heat conduction. One end of the nitrogen preheating coil is connected to an external nitrogen source through the gas flow meter, and the other end is connected to the inside of the heating cavity to realize the preheating of nitrogen before it enters the heating cavity, thus avoiding cold nitrogen from disrupting the temperature balance inside the cavity.

[0006] The sample lifting assembly includes a sample carrying lifting mechanism, which consists of a lifting drive rod and a lifting platform. The lifting drive rod is an electric push rod structure, installed at the bottom center of the lower heated aluminum substrate, and its axis coincides with the axis of the lower heated aluminum substrate. The lifting platform is formed by welding a metal tube and a metal disk, specifically, one end of the metal tube is welded to the center of the metal disk. The lower end of the metal tube is fixedly connected to the output end of the lifting drive rod. The diameter of the metal disk is adapted to the inner diameter of the heating cavity and is used to place standard aluminum sample dishes. Through the extension and retraction of the lifting drive rod, the lifting platform can be moved up and down synchronously, realizing convenient placement and precise positioning of standard aluminum sample dishes.

[0007] The opening and closing assembly includes an upper base opening and closing slide mechanism, which consists of a slide bracket and an electric slide. The slide bracket connects the upper heated aluminum base to the slide block. By moving the sliding block of the electric slide block up and down, the upper heated aluminum base can be driven to rise and fall synchronously, realizing the automatic opening and closing of the heating cavity without manual operation.

[0008] The control component includes a multi-channel temperature control system. The signal input terminals of the multi-channel temperature control system are electrically connected to the signal output terminals of the lower substrate temperature measuring thermocouple, the upper substrate temperature measuring thermocouple, and the sample temperature measuring thermocouple, respectively, for receiving temperature signals collected by each thermocouple. The control output terminals of the multi-channel temperature control system are electrically connected to the control terminals of the lower heating rod, the upper heating rod, the lifting drive rod, the electric slide, and the nitrogen source, respectively. It can automatically control the start and stop of the lower heating rod and the upper heating rod according to the received temperature signals, stabilize the temperature of the heating chamber within the set range, and accurately regulate the sample heating rate and nitrogen flow rate. It can also control the movement of the lifting drive rod and the electric slide to achieve automated operation.

[0009] Compared with the prior art, the asphalt volatilization loss measuring device provided by this utility model has the following beneficial effects:

[0010] First, it solves the problems of cold nitrogen temperature disturbance and blind spots in sample temperature measurement. By tightly fitting the nitrogen preheating coil with the lower heating aluminum substrate, the nitrogen is preheated to near the target temperature before entering the cavity, avoiding disruption of the temperature balance. At the same time, the through-type sample temperature measuring thermocouple extends directly into the sample to collect the temperature in real time, greatly improving accuracy. Second, it optimizes operational efficiency and safety. The upper substrate opening and closing slide mechanism enables automatic opening and closing, and the sample carrying lifting mechanism drives the sample dish to automatically rise and fall, eliminating the need for manual contact with the high-temperature cavity, improving operational efficiency and completely eliminating the risk of burns. Attached Figure Description

[0011] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, do not constitute an undue limitation of the present invention. In the drawings:

[0012] Figure 1 This is a schematic diagram of an embodiment of the present invention.

[0013] Figure 2 This is a cross-sectional view of the heating temperature control component according to an embodiment of the present invention.

[0014] Figure 3 This is a cross-sectional view of the upper and lower heated aluminum substrates in the snap-fit ​​state of an embodiment of this novel experimental design.

[0015] Among them, 1. Heating temperature control component, 10. Upper heating aluminum substrate, 101.1# heating well, 102.2# heating well, 103. Through-hole temperature measuring well, 104.1# temperature measuring well, 105. Exhaust gas outlet, 11. Lower heating aluminum substrate, 111.3# heating well, 112.4# heating well, 113.2# temperature measuring well, 114. Nitrogen inlet, 115. Spiral groove, 12. Heating rod, 13. Substrate temperature measuring thermocouple, 14. Sample temperature measuring thermocouple, 15. Aluminum sample dish, 2. Nitrogen preheating coil, 20. Gas flow meter, 3. Slide table, 30. Slide table support, 4. Lifting rod, 40. Lifting platform, 5. Control component. Detailed Implementation

[0016] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. 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. The present invention is not limited to the specific embodiments disclosed below.

[0017] Please see Figure 1-3 This utility model provides a device for measuring the volatilization loss of asphalt, comprising: a heating and temperature control component 1, an upper heating aluminum substrate 10, a heating well 1# 101, a heating well 2# 102, a through-temperature measuring well 103, a temperature measuring well 1# 104, a waste gas outlet 105, a lower heating aluminum substrate 11, a heating well 3# 111, a heating well 4# 112, a temperature measuring well 2# 113, a nitrogen inlet 114, a spiral groove 115, a heating rod 12, a substrate temperature measuring thermocouple 13, a sample temperature measuring thermocouple 14, an aluminum sample dish 15, a nitrogen preheating coil 2, a gas flow meter 20, a slide table 3, a slide table support 30, a lifting rod 4, a lifting platform 40, and a control component 5.

[0018] Heating wells 101, 202, 311, and 412 are each equipped with a heating rod 12 for heating the upper heating aluminum substrate 10, the lower heating aluminum substrate 11, and the nitrogen in the nitrogen preheating coil 2. A sample temperature measuring thermocouple 14 is installed in the through-hole 103, and the sample temperature measuring thermocouple 14 has an axial elastic movement space within the through-hole 103. A substrate temperature measuring thermocouple 13 is installed in each of the heating wells 104 and 213 for real-time monitoring and adjustment of the temperature of the upper heating aluminum substrate 10 and the lower heating aluminum substrate 11. The heated aluminum substrate 10 is connected to the slide table 3 via the slide table support 30; the nitrogen preheating coil 2 is coiled around the spiral groove of the lower heated aluminum substrate 11, one end of which is connected to an external nitrogen source via a gas flow meter 20 connected in series, and the other end is connected to the nitrogen inlet 114 of the lower heated aluminum substrate 11; the exhaust outlet 105 is connected to an external vent pipe; the lifting platform 40 is axially inserted into the lower heated aluminum substrate 11, and the metal tube at the bottom of the metal disc is connected to the movable rod of the lifting rod 4; the control component 5 is electrically connected to all the heating rods 12, substrate temperature measuring thermocouples 13, sample temperature measuring thermocouples 14, slide table 3, lifting rod 4, and gas flow meter 20 on the device.

[0019] Taking the determination of volatilization loss of asphalt samples at 350℃ as an example, 15g of pre-treated asphalt sample is weighed and evenly spread in an aluminum sample dish 15. The control component 5 is activated with all heating rods 12 and the substrate temperature measuring thermocouple 13 to preheat the heating temperature control component 1. A nitrogen source is turned on, and the flow rate of nitrogen flowing into the nitrogen preheating coil 2 is adjusted using a gas flow meter 20 to 10mL / min ± 0.1mL / min. When the overall temperature of the upper heated aluminum substrate 10 and the lower heated aluminum substrate 11 reaches 350 ± 10℃, the slide 3 and the lifting rod... 4. Simultaneously, the slide table 3 raises the upper heating aluminum substrate 10 to the designated height; the lifting rod 4 pushes the lifting platform 40 out of the lower heating aluminum module 11, quickly placing the aluminum sample dish 15 containing the asphalt sample into the center of the metal disc of the lifting platform 40; after placement, the slide table 3 snaps the upper heating aluminum substrate 10 onto the lower heating aluminum substrate 11, forming a cavity between them. Simultaneously, the lifting rod 4 lowers the lifting platform 40 back into the cavity, heating the asphalt sample in the aluminum sample dish 15. Then, the sample temperature measuring thermocouple 14 is pushed downwards into the asphalt sample, adjusting its insertion depth to ensure it is completely covered by the asphalt sample but does not contact the bottom of the aluminum sample dish, measuring the heating rate of the asphalt sample. While the asphalt sample is heated and volatilized, nitrogen gas is introduced into the nitrogen preheating coil 2, heated by the lower heating aluminum substrate 11, and then enters the cavity through the nitrogen inlet 114 of the lower heating aluminum substrate 11 to purge the asphalt sample. This serves as both carrier gas and protective gas, blowing the volatilized waste gas from the upper heating aluminum substrate 10 out through the waste gas outlet 105. Heating and purging are continued for 30 minutes. After 30 minutes, the upper heating aluminum substrate 10 and the lifting platform 4 are raised, and the aluminum sample dish 15 is lifted out. The control component 5 stops heating and nitrogen purging. The aluminum sample dish 15 is then held in place with clamps or lifted with a heat-insulating plate for cooling. Once a hard shell forms on the sample surface, the aluminum sample dish 15 containing the sample is placed in a desiccator for cooling for 30 minutes, and then its mass loss is measured.

Claims

1. A device for measuring asphalt volatilization loss, characterized in that, The system includes a heating and temperature control component, a nitrogen preheating component, a sample lifting component, an opening and closing component, and a control component. The heating and temperature control component comprises an upper heating aluminum substrate and a lower heating aluminum substrate. The upper and lower heating aluminum substrates are sized to fit each other and are correspondingly distributed vertically, forming a sealed heating cavity when closed. The lower heating aluminum substrate has a lower heating rod mounting hole and a lower substrate temperature measuring hole inside. A lower heating rod is installed in the lower heating rod mounting hole, and a lower substrate temperature measuring thermocouple is installed in the lower substrate temperature measuring hole. The outer circumferential surface of the aluminum substrate is machined with spiral grooves; the interior of the upper heating aluminum substrate has an upper heating rod mounting hole and two temperature measuring holes. An upper heating rod is installed in the upper heating rod mounting hole. One temperature measuring hole houses an upper substrate temperature measuring thermocouple, and the other temperature measuring hole penetrates the upper and lower end faces of the upper heating aluminum substrate, housing a sample temperature measuring thermocouple. The lower end of the sample temperature measuring thermocouple can extend into the sample within the heating chamber. The nitrogen preheating assembly includes a nitrogen preheating coil and a gas flow meter. The sample lifting assembly is wound and fixed on the outer spiral groove of the lower heating aluminum substrate. One end of the assembly is connected to an external nitrogen source via a gas flow meter, and the other end is connected to the interior of the heating chamber. The sample lifting assembly includes a sample carrying lifting mechanism consisting of a lifting drive rod and a lifting platform. The lifting drive rod adopts an electric push rod structure and is installed at the center of the bottom of the lower heating aluminum substrate, with its axis coinciding with the axis of the lower heating aluminum substrate. The lifting platform is welded from a metal tube and a metal disk. One end of the metal tube is connected to the center of the metal disk, and the other end is connected to... The output end of the lifting drive rod is fixed, and the diameter of the metal disc is adapted to the inner diameter of the heating chamber; the opening and closing assembly includes an upper base opening and closing slide mechanism composed of a slide bracket and an electric slide, the slide bracket connecting the upper heated aluminum base and the slider of the electric slide; the control assembly includes a multi-channel temperature control system, whose signal input end is electrically connected to the lower base temperature measuring thermocouple, the upper base temperature measuring thermocouple, and the sample temperature measuring thermocouple, and whose control output end is electrically connected to the lower heating rod, the upper heating rod, the lifting drive rod, the electric slide, and the nitrogen source control end.

2. The asphalt volatilization loss measuring device according to claim 1, characterized in that, The lower heating aluminum substrate has two lower heating rod mounting holes in the vertical direction, and one lower heating rod is installed in each lower heating rod mounting hole; the upper heating aluminum substrate has two upper heating rod mounting holes in the vertical direction, and one upper heating rod is installed in each upper heating rod mounting hole.

3. The asphalt volatilization loss measuring device according to claim 1, characterized in that, The nitrogen preheating coil is made of stainless steel and is tightly bonded to the lower heating aluminum substrate.

4. The asphalt volatilization loss measuring device according to claim 1, characterized in that, The upper heating aluminum substrate has an exhaust gas outlet, which is connected to an external vent pipe; the lower heating aluminum substrate has a nitrogen inlet, and the end of the nitrogen preheating coil away from the gas flow meter is connected to the nitrogen inlet. Nitrogen enters the heating chamber through the nitrogen inlet and is discharged from the exhaust gas outlet.

Images