CN-121990315-A - Spiral feeding device and method for asphalt

CN121990315ACN 121990315 ACN121990315 ACN 121990315ACN-121990315-A

Abstract

The invention discloses a spiral feeding method for asphalt, which relates to the technical field of asphalt conveying and comprises the steps of collecting spiral torque, rotating speed, temperature of a feeding hole, temperature of a blade and a set value of temperature of heat conducting oil at the last moment in the running process of a spiral feeding machine in real time, obtaining apparent viscosity of asphalt according to the torque and the rotating speed, obtaining reference viscosity according to the temperature of the discharging hole, determining current viscosity deviation, obtaining dynamic temperature difference between the blade and the asphalt according to the temperature of the blade and the temperature of the feeding hole, determining response delay time according to the rotating speed of the spiral, predicting the viscosity deviation after the delay time by combining with a viscosity change rate, obtaining temperature adjustment quantity of the heat conducting oil based on the predicted viscosity deviation, the viscosity change rate and the dynamic temperature difference, and updating the set value of the temperature at the current moment to execute heating control. According to the invention, by introducing dynamic temperature difference and response delay prediction, the advanced compensation of asphalt viscosity fluctuation is realized, and the stability and control precision of spiral feeding are obviously improved.

Inventors

WANG JIANLI
LI JIAJIA
ZHAO GUOLIANG
ZHANG JIANQING

Assignees

山东坤达公路材料有限公司

Dates

Publication Date: 20260508
Application Date: 20260305

Claims (10)

1. A spiral feeding method for asphalt, which is characterized by comprising the following steps: Collecting data in the running process of the spiral feeding machine in real time, wherein the data at least comprise spiral torque, spiral rotating speed, temperature of a feeding hole, temperature of a discharging hole, a plurality of temperature measuring point values distributed along a spiral blade and a heat conducting oil temperature set value at the last moment; obtaining apparent viscosity of asphalt according to the spiral torque and the spiral rotating speed, obtaining reference viscosity according to the temperature of a discharge hole, and further determining current viscosity deviation; acquiring a dynamic temperature difference between the spiral blade and asphalt according to the blade temperature measuring point value and the temperature of the feeding and discharging port; Determining response delay time of asphalt viscosity to temperature change of heat conduction oil according to the current spiral rotating speed, and predicting predicted viscosity deviation after the response delay time by combining with the current viscosity change rate; Based on the predicted viscosity deviation, the current viscosity change rate and the dynamic temperature difference, the adjustment amount of the heat transfer oil temperature is obtained, and the heat transfer oil temperature set value at the current moment is updated accordingly to execute heating control.
2. The spiral feeding method for asphalt according to claim 1, wherein the apparent viscosity of the asphalt is calculated by the following formula: Wherein, the Indicating time of day The apparent viscosity of the asphalt of (a) is, Indicating time of day Is used for the screw torque of the motor, Indicating time of day Is used for the spiral rotation speed of the (a), Representing the geometric constant of the screw conveyor.
3. The spiral feeding method for asphalt according to claim 1, wherein the reference viscosity is calculated by the following formula: Wherein, the Indicating time of day The asphalt of the discharge port of the (2) is referenced to the viscosity, Represents the theoretical minimum viscosity of asphalt, Indicating the temperature constant of the material, Indicating time of day Is arranged at the discharge port.
4. The spiral feeding method for asphalt according to claim 1, wherein the current viscosity deviation is obtained by the following formula: Wherein, the Indicating the current deviation of the viscosity of the fluid, Indicating time of day The apparent viscosity of the asphalt of (a) is, Indicating time of day The asphalt reference viscosity of the discharge port.
5. The spiral feeding method for asphalt according to claim 1, wherein the dynamic temperature difference is obtained by: obtaining average blade temperature And average temperature of asphalt The method comprises the steps of obtaining dynamic temperature difference based on average blade temperature and asphalt average temperature, and obtaining the dynamic temperature difference specifically as follows: , wherein, Indicating the number of blade temperature sensors, Represent the first The measurement of the individual blade temperature sensors at the moment, The temperature of the feeding port is indicated, Indicating the temperature of the discharge port.
6. The spiral feeding method for asphalt according to claim 1, wherein the response delay time is obtained by: The pitch based on current screw rotational speed and helical blade obtains pitch axial displacement speed, specifically does: Wherein, the Indicating the axial movement speed of the asphalt, Indicating the current rotational speed of the spiral, Representing the pitch of the helical blade; The response delay time is obtained based on the axial movement speed of asphalt, the total length of the screw conveyor and the inherent delay time of heat conduction, and is specifically as follows: Wherein, the The response delay time is indicated as such, Indicating the total length of the screw conveyor, Indicating the axial movement speed of the asphalt, Indicating the intrinsic delay time of heat conduction.
7. The spiral feeding method for asphalt according to claim 1, wherein the viscosity deviation after the response delay time is obtained by the following formula: Wherein, the Represents the predicted viscosity deviation after a response delay time, The response delay time is indicated as such, The rate of change of the viscosity is indicated, Representing the current viscosity deviation; The viscosity change rate is approximately calculated by a difference method: Wherein, the The rate of change of the viscosity is indicated, Indicating the apparent viscosity at the present moment, The apparent viscosity at the last sampling instant is indicated, Representing the sampling time interval.
8. The spiral feeding method for asphalt according to claim 1, wherein the adjustment amount of the temperature of the heat transfer oil is calculated by the following formula: Wherein, the Represents the adjustment amount of the heat transfer oil temperature at the present time, Indicating the deviation of the predicted viscosity, The rate of change of the viscosity is indicated, Represents the dynamic temperature difference and the temperature difference, The scale factor is represented by a ratio of, Representing the differential coefficient of the sample, Representing the feed forward coefficient.
9. The spiral feeding method for asphalt according to claim 1, wherein the set value of the temperature of the heat conducting oil at the current moment is updated by the following formula: Wherein, the Indicating the set value of the temperature of the heat conducting oil at the current moment, The current temperature adjustment amount of the heat conduction oil is represented, Indicating the set point of the temperature of the conduction oil at the previous moment.
10. The spiral feeding device for asphalt comprises a spiral feeding machine and is characterized in that the spiral feeding method for asphalt is adopted according to any one of claims 1-9, the spiral feeding machine is of a hollow blade or jacket structure, and heat conduction oil is filled in the blades.

Description

Spiral feeding device and method for asphalt Technical Field The invention belongs to the technical field of asphalt conveying, and particularly relates to a spiral feeding device and method for asphalt. Background At present, various asphalt screw conveying devices are disclosed in the prior art, for example, asphalt is insulated by arranging a heat conducting oil heating pipe on the outer wall of a shell, or conveying temperature is maintained by a heatable bearing structure. These schemes typically employ simple temperature feedback control, i.e., adjusting the heating power of the conduction oil based on the deviation of the outlet temperature from the set point. In practical engineering applications, operators also often manually adjust the heating temperature empirically to account for asphalt viscosity variations. However, the prior art has the following defects that firstly, only temperature control is concerned and the key parameter of asphalt viscosity is ignored, and the change of conveying resistance cannot be directly reflected, secondly, the dynamic temperature difference between a spiral blade and asphalt is not considered, when the blade temperature is inconsistent with the core temperature of a material, local wall sticking or coking is easy to occur, thirdly, the response delay of asphalt viscosity to temperature change is not considered, when the temperature of heat conduction oil is adjusted, the viscosity change can be transmitted to a discharge port only after a long time is required, so that control lag is caused, and torque fluctuation and even equipment overload are easy to occur. Therefore, the prior art is difficult to realize the accurate and stable control of the pitch spiral feeding. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a spiral feeding device and method for asphalt, and solves the problems. In order to achieve the purpose, the invention is realized by the following technical scheme that the spiral feeding method for asphalt comprises the following steps: Collecting data in the running process of the spiral feeding machine in real time, wherein the data at least comprise spiral torque, spiral rotating speed, temperature of a feeding hole, temperature of a discharging hole, a plurality of temperature measuring point values distributed along a spiral blade and a heat conducting oil temperature set value at the last moment; obtaining apparent viscosity of asphalt according to the spiral torque and the spiral rotating speed, obtaining reference viscosity according to the temperature of a discharge hole, and further determining current viscosity deviation; acquiring a dynamic temperature difference between the spiral blade and asphalt according to the blade temperature measuring point value and the temperature of the feeding and discharging port; Determining response delay time of asphalt viscosity to temperature change of heat conduction oil according to the current spiral rotating speed, and predicting predicted viscosity deviation after the response delay time by combining with the current viscosity change rate; Based on the predicted viscosity deviation, the current viscosity change rate and the dynamic temperature difference, the adjustment amount of the heat transfer oil temperature is obtained, and the heat transfer oil temperature set value at the current moment is updated accordingly to execute heating control. Based on the technical scheme, the invention also provides the following optional technical schemes: According to a further technical scheme, the apparent viscosity of the asphalt is calculated by the following formula: Wherein, the Indicating time of dayThe apparent viscosity of the asphalt of (a) is,Indicating time of dayIs used for the screw torque of the motor,Indicating time of dayIs used for the spiral rotation speed of the (a),The geometric constant (in cubic meters) of the screw conveyor is shown. Further technical proposal is that the reference viscosity is calculated by the following formula: Wherein, the Indicating time of dayThe asphalt of the discharge port of the (2) is referenced to the viscosity,Represents the theoretical minimum viscosity of asphalt,Indicating the material temperature constant (in kelvin,,Indicating the activation energy required for the asphalt to flow,Representing an ideal gas constant),Indicating time of dayIs arranged at the discharge port. The current viscosity deviation is obtained by the following formula: Wherein, the Indicating the current viscosity deviation (time of dayViscosity deviation of (c) of the oil-based fluid),Indicating time of dayThe apparent viscosity of the asphalt of (a) is,Indicating time of dayThe asphalt reference viscosity of the discharge port. The dynamic temperature difference is obtained through the following steps: obtaining average blade temperature And average temperature of asphaltThe method comprises the steps of obtaining dynamic temperature d