Summary of the invention
For the shortcoming of currently available technology, the object of this invention is to provide a kind of drying plant of sheet material, solve existing market intelligent product degree not high, the shortcomings such as inefficiency.
To achieve these goals, technical scheme of the present invention is as follows: comprise casing, heater block, temperature sensor, Programmable Logic Controller and conveyer belt, described conveyer belt is through casing, heater block and temperature sensor are arranged in casing, and heater block is connected with Programmable Logic Controller with temperature sensor; Described drying plant comprises thickness detection apparatus further, the thickness of sheet material is automatically detected by thickness detection apparatus and obtains, described thickness detection apparatus and programmable automatic controller data cube computation, the thickness data of sheet material is sent to Programmable Logic Controller by thickness detector; Programmable Logic Controller is according to the change of the thickness of sheet material and moisture control temperature.
Preferably, thickness detection apparatus is arranged on the entry position place of casing, and/or apart from the support outside the casing of the certain distance of tank inlet.
Preferably, by arranging the thickness detection apparatus of diverse location, repetitive measurement sheet metal thickness carrys out calculated thickness mean value.
Preferably, thickness detection apparatus comprises infrared transmitter and infrared remote receiver, and infrared rays survey sheet metal thickness launched by infrared transmitter, and infrared remote receiver accepts the thickness data that infrared transmitter sends, and thickness data is sent to Programmable Logic Controller.
Preferably, infrared transmitter comprises the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit that level is equidistantly placed; Infrared remote receiver comprises the first infrared receiver, the second infrared receiver and the 3rd infrared receiver that level is equidistantly placed, and the first infrared receiver, the second infrared receiver and the 3rd infrared receiver and the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit receive the infrared ray that the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit are launched respectively.
Preferably, infrared emission unit be arranged on distance entrance keep at a certain distance away across on the support of driving-belt, infrared receiving unit is arranged on the entry position of casing, and level is corresponding respectively for the first infrared receiver, the second infrared receiver and the 3rd infrared receiver and the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit.
Preferably, infrared receiving unit be arranged on distance entrance keep at a certain distance away across on the support of driving-belt, infrared emission unit is arranged on the entry position of casing, and level is corresponding respectively for the first infrared receiver, the second infrared receiver and the 3rd infrared receiver and the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit.
Preferably, it is characterized in that, transfer rate and heating and temperature control mode as follows: in Programmable Logic Controller stored in reference data sheet metal thickness be L, quality moisture content is S, the temperature of heating is T, the transfer rate of conveyer belt to be V be sheet metal thickness be L, quality moisture content be S time, the absolute temperature of the heating needed is T, and the transfer rate of conveyer belt is V;
When the thickness of sheet material is for becoming l, quality moisture content is that when becoming s, the biography speed of conveyer belt and heating-up temperature meet following relation:
In Programmable Logic Controller stored in reference data sheet metal thickness be L, quality moisture content is S, the temperature of heating is T, the transfer rate of conveyer belt to be V be sheet metal thickness be L, quality moisture content be S time, the absolute temperature of the heating needed is T, and the transfer rate of conveyer belt is V;
When the thickness of sheet material is for becoming l, quality moisture content is when becoming s, and the temperature of heating meets following relation:
V keeps reference speed V constant, and heating-up temperature adjustment is as follows: t=T*(s/S)
a* (l/L)
b, wherein a, b are parameter, 1.07<a<1.13,1.15<b<1.20;
The following condition of demand fulfillment in above-mentioned formula: 0.8<s/S<1.2,0.8<l/L<1.2;
In above-mentioned formula, temperature T, t are absolute temperature, and unit is K, and be the average heating-up temperature in casing, speed V, v unit is m/s, and sheet metal thickness L, l are centimetre that moisture content s, S are mass percent.
Compared with prior art, drying plant of the present invention has following advantage:
1) temperature and/or line speed in Programmable Logic Controller automatic control box body, realize the intelligentized oven dry of sheet material.
2) by arranging multiple heater block, realize the Based Intelligent Control to each heater block, thus realize the distribution preset of the temperature in whole casing.
3) infrared heating parts are arranged closer to tank outlet than heating using microwave parts, can reach dry fast, and drying effect are good.
4) best control rate and the relational expression of temperature is drawn by large quantity research.
5) by thickness setting automatic detection device, the intelligence degree of equipment is further increased.
Detailed description of the invention
It should be noted that, sheet material herein refers to the material of tabular, the timber, warming plate etc. of such as tabular.
As shown in Figure 1, a kind of drying plant of sheet material 8, comprise casing 1, heater block 3, temperature sensor 7, Programmable Logic Controller 5 and conveyer belt 2, described conveyer belt 2 is through casing 1, heater block 3 and temperature sensor 7 are arranged in casing, and heater block 3 is connected with Programmable Logic Controller 5 with temperature sensor 7.
As preferably, conveyer belt arranges speed control unit, and speed control unit and Programmable Logic Controller 5 carry out data cube computation, and Programmable Logic Controller 5 Negotiation speed control assembly controls the speed of conveyer belt.
As preferably, speed control unit comprises speed detecting component, and the conveyer belt data of detection are sent to Programmable Logic Controller by speed detecting component, and Programmable Logic Controller adjusts the power of conveyer belt motor according to the data detected.If the speed detected is less than the data that Programmable Logic Controller calculates, increase the power of motor, otherwise, reduce the power of motor.Preferably, the transfer rate of conveyer belt is adjusted by the rotating speed of Electric Machine Control delivery wheel 9.
As preferably, the temperature sensor in casing is multiple, calculates mean temperature by the mean value arranging multiple temperature sensor measurement data.
As preferably, the perpendicular longitudinal direction of the axial direction that the temperature sensor in casing is set to transmit along conveyer belt arranges many rows, and distance of each row is identical.
As preferably, as shown in Figure 3, the arrangement mode of the temperature sensor 7 of adjacent row is wrong row.By the mode that mistake is arranged, the temperature of longitudinally upper axially different position can be obtained, avoid only measuring same temperature axially, ensure the accuracy of measurement data.
As preferably, casing 1 is cross section is trapezoidal cavity, and entrance 6 and outlet arrange Electrically operated gate, and the aperture of described Electrically operated gate can regulate.Central controller regulates the aperture of Electrically operated gate automatically according to the thickness of sheet material of input, prevents that aperture is excessive causes energy loss, has reached the object of economize energy.
As preferably, also comprise temperature detector 4, certainly, temperature detector is conversion sensor reading, sends it to PLC, when necessary, directly the data of temperature sensor measurement directly can be sent to controller, or set temperature detector, such as Fig. 1 in controller.
Preferably, the transfer rate of conveyer belt is 0.4-0.6m/s.
As preferably, arrange the thermal treatment zone in casing, along conveyer belt direction of transfer, Heating Zone Temperature is that continuity distribution reduces gradually.Make sheet material more and more higher along with degree of drying like this, need heat fewer and feweri, thus save energy.
As preferably, along conveyer belt direction of transfer, the range of decrease of the temperature of the thermal treatment zone increases gradually.If temperature t to be set to the function of the distance x of distance thermal treatment zone entrance, t=f(x), then in the thermal treatment zone, f'(x) <0, f''(x) >0, wherein f'(x), f''(x) be f(x respectively) first order derivative and second derivative.
T is the mean temperature on X position cross section.In practice can by arranging the mean temperature of multiple temperature sensor measurement, or the mean temperature on the cross section measured by infrared radiation thermometer.
Show by experiment, by the change of said temperature and the change of amplification, the drying of sheet material can be made to obtain best effect, but also can economize energy.
Why limit the thermal treatment zone herein, be because casing in also preheating zone may be set, the thermal treatment zone be herein exactly preheating zone after heating region.Certainly, sometimes preheating zone is not set, only the thermal treatment zone is set.
Preferably, the temperature range of oven dry is 85-120 DEG C.
As preferably, described heater block 3 comprises infrared heating parts and heating using microwave parts two kinds, and in the thermal treatment zone, infrared heating parts are arranged closer to tank outlet than heating using microwave parts.Main cause is that infrared heating parts are different with the principle that heating using microwave parts heat, because sheet material passed through heating using microwave before this, the hydrone in sheet material is made just to produce the motion of vibration and rotational energy level, other molecules of surrounding are rubbed fast, thus accelerate hydrone from the inner outwards evaporation of sheet material, by the time when hydrone evaporate near plate surface substantially, then carry out baking type heating by infrared heating parts, thus accelerate the drying of sheet material.
In practical work process, need a best relation between the speed of conveyer belt and heating-up temperature, if the excessive velocities of conveyer belt, then the heat time is short, can affect heating quality, if the speed of conveyer belt is excessively slow, the heat time is long, then may waste too many energy, in like manner, if heating-up temperature is too low, heating quality can be affected, if heating-up temperature is too high, can cause wasting too many energy.Therefore by a large amount of experiments, the relation between best heating-up temperature and transfer rate has been drawn.
Thickness and humidity that described drying plant can realize according to heating sheet material adjust heating-up temperature and conveyer belt transfer rate automatically.Control mode is as follows: when supposing that sheet metal thickness is L, quality moisture content is S, and in casing, the temperature of heating is T(absolute temperature), time the transfer rate of conveyer belt is V, represent the drying effect meeting certain condition.Above-mentioned sheet metal thickness is L, quality moisture content is that S, speed V and temperature T are called root thickness, reference humidity, reference speed and fiducial temperature, i.e. reference data.Described reference data stores in the programmable controller.
Reference data represents the data of the drying effect meeting certain condition.Can be such as satisfied certain drying effect, such as drying effect is sheet material moisture content be 0.02%, or when reaching certain drying effect, the energy expended is minimum.Certainly preferred condition is when reaching certain drying effect, and the minimum data of the energy expended are as reference data.
The temperature adjusted by following formula and speed also can meet the drying effect of the certain condition that reference data reaches substantially.
When the thickness of sheet material is for becoming l, quality moisture content is when becoming s, and the temperature of heating and speed meet one of following three kinds of different operational modes:
First mode: v keeps reference speed V constant, and heating-up temperature change is as follows:
T=T*(s/S)
a* (l/L)
b, wherein a, b are parameter, 1.07<a<1.13,1.15<b<1.20; Preferably, a=1.10, b=1.18;
Second pattern: t keeps fiducial temperature T constant, and the transfer rate change of conveyer belt is as follows:
V/v=(s/S)
c* (l/L)
d, wherein c, d are parameter, 1.12<c<1.18,1.25<d<1.29; Preferably, c=1.15, d=1.27
3rd pattern: v and t is variable, the relation of the transfer rate of heating-up temperature and conveyer belt is as follows:
(v*t)/(V*T)=g*(s/S)
e* (l/L)
f, wherein g, e, f are parameter, and g meets following formula:
(s/S)/(l/L) >1,0.95<g<0.98; Preferably, g=0.96;
(s/S)/(l/L) <1,1.04<g<1.08; Preferably, g=1.06;
(s/S)/(l/L)=1,0.98<g<1.04; Preferably, g=1.02;
Preferably, the 3rd pattern is chosen ((1-v/V)
2+ (1-t/T)
2) minimum one group of v and t of value; First group of v and t met the demands can certainly be selected, also can select one group immediately from v and t satisfied condition;
1.10<e<1.15,1.18<f<1.20; Preferably, e=1.13, f=1.19.
The wherein following condition of demand fulfillment in the formula of above-mentioned Three models: 0.8<s/S<1.2,0.8<l/L<1.2.
Above-mentioned formula is through a large amount of actual verification, meets the needs of sheet material actual drying completely.
In actual applications, store in Programmable Logic Controller and organize reference data more, then the data (sheet metal thickness and sheet material moisture content) that input according to user of Programmable Logic Controller, meeting 0.8<s/S<1.2, in 0.8<l/L<1.2 situation, automatically selecting suitable reference data as foundation.
Preferably, when under appearance two groups or many group reference data situations, the interface of the reference data that user can be provided to select, preferred, system can be selected automatically ((1-s/S)
2+ (1-l/L)
2) minimum one of value.
Described Three models only can store one in the programmable controller, also can store two kinds or three kinds in the programmable controller.
In time having multiple temperature sensor, heating-up temperature is the mean temperature of multiple temperature sensor measurement in casing.
In above-mentioned formula, temperature T, t are absolute temperature, and unit is K, and speed V, v unit is m/s, and sheet metal thickness L, l are cm(centimetre), moisture content s, S are mass percent.
Preferably, when adjusting temperature, the heating power of the heater block of all thermals treatment zone takes identical amplification or the range of decrease, such as, increase by 10% all simultaneously.
Preferably, when adjusting temperature, the heating power of all thermal treatment zone heater blocks takes different amplification or the range of decrease, and along with the direction of transfer of conveyer belt, the amplitude that the heating power of the heater block of the thermal treatment zone increases or reduces reduces gradually, such as, along the direction of transfer of conveyer belt, heater block above increases by 15%, increase successively 12% below, 11%, etc.
Preferably, arrange preheating zone in casing, preheating zone is arranged on the front portion of the thermal treatment zone and is connected with the thermal treatment zone.In preheating zone, along conveyer belt direction of transfer, the temperature of preheating zone is continuity distribution rising gradually, and preferably along conveyer belt direction of transfer, the amplification of temperature increases gradually.If temperature t to be set to the function of the distance x of distance entrance, t=f(x), then in preheating zone, f'(x) >0, f''(x) >0, wherein f'(x), f''(x) be f(x respectively) first order derivative and second derivative.
T is the mean temperature on X position cross section.In practice can by arranging the mean temperature of multiple temperature sensor measurement, or the mean temperature on the cross section measured by infrared radiation thermometer.
Show by experiment, by the change of said temperature and the change of amplification, the preheating of sheet material can be made to obtain extraordinary effect, but also can economize energy more than 10%.
When arranging preheating zone, the temperature T of preceding formula, t be comprise preheating zone together with the thermal treatment zone mean temperature, the temperature by preheating zone and the thermal treatment zone is considered as a mean temperature.
When arranging preheating zone, preferably, when adjusting temperature, the heating power of the heater block of all preheating zones takes identical amplification or the range of decrease, such as, increase by 10% all simultaneously.
Preferably, when adjusting temperature, the heating power of preheating zone heater block takes different amplification or the range of decrease, and along with the direction of transfer of conveyer belt, the amplitude that the heating power of the heater block of preheating zone increases or reduces raises gradually, such as, along the direction of transfer of conveyer belt, heater block above increases by 8%, increase successively 10% below, 11%, etc.
By the change of above-mentioned amplification, can very big economize energy, compared with identical with amplification, and fully can ensure the accuracy of dry result.Prove by experiment, the situation of amplification change, error is less, and heating effect is better.
The invention also discloses a kind of method realizing drying equipment intelligent operation, comprise the steps:
1) store one group or organize reference data first in the programmable controller more: sheet metal thickness is L, quality moisture content is S, in casing the temperature of heating be T(absolute temperature), the transfer rate of conveyer belt is V;
2) thickness of input slab and water content on operation interface;
3) Programmable Logic Controller is according to the thickness of the sheet material of input and water content, and user selects perform or automatically perform (when such as only having a kind of operational mode) one of three patterns below:
First mode.V keeps reference speed V constant, and heating-up temperature change is as follows:
T=T*(s/S)
a* (l/L)
b, wherein a, b are parameter, 1.07<a<1.13,1.15<b<1.20; Preferably, a=1.10, b=1.18;
Second pattern.T keeps fiducial temperature T constant, and the transfer rate change of conveyer belt is as follows:
V/v=(s/S)
c* (l/L)
d, wherein c, d are parameter, 1.12<c<1.18,1.25<d<1.29; Preferably, c=1.15, d=1.27
3rd pattern.V and t is variable, and the relation of the transfer rate of heating-up temperature and conveyer belt is as follows:
(v*t)/(V*T)=g*(s/S)
e* (l/L)
f, wherein g, e, f are parameter, and g meets following formula:
(s/S)/(l/L) >1,0.95<g<0.98; Preferably, g=0.96;
(s/S)/(l/L) <1,1.04<g<1.08; Preferably, g=1.06;
(s/S)/(l/L)=1,0.98<g<1.04; Preferably, g=1.02;
Preferably, the 3rd pattern is chosen ((1-v/V)
2+ (1-t/T)
2) minimum one group of v and t of value; First group of v and t met the demands can certainly be selected, also can select one group immediately from v and t satisfied condition;
1.10<e<1.15,1.18<f<1.20; Preferably, e=1.13, f=1.19.
The wherein following condition of demand fulfillment in the formula of above-mentioned Three models: 0.8<s/S<1.2,0.8<l/L<1.2.
4) drying plant starts to carry out drying operation.
As preferably, input in step 1) and organize reference data more;
As preferably, when under appearance two groups or many group reference data situations, the reference data that user can be selected by user interface.
Preferably, system can be selected ((1-s/S) automatically
2+ (1-l/L)
2) the minimum reference data of value.
Preferably, the thickness of sheet material is automatically detected by thickness detection apparatus and obtains, and described thickness detection apparatus and programmable automatic controller data cube computation, the thickness data of sheet material is sent to Programmable Logic Controller by thickness detector.Take the major advantage of thickness detection apparatus to be the thickness data of automatic acquisition sheet material, avoid the complicated procedures of manual input thickness data, improve efficiency and the degree of accuracy of oven dry.
Preferably, thickness detection apparatus is arranged near the entry position of casing, such as, be arranged on tank inlet position, and/or on the support of the casing outside of the certain distance of distance tank inlet.Also can by arranging the thickness detection apparatus of diverse location, repetitive measurement thickness carrys out calculated thickness mean value.
Preferably, thickness detection apparatus comprises infrared transmitter and infrared remote receiver, and infrared rays survey sheet metal thickness launched by infrared transmitter, and infrared remote receiver accepts the thickness data that infrared transmitter sends, and thickness data is sent to Programmable Logic Controller.
Preferably, infrared transmitter comprises the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit that level is equidistantly placed; Infrared remote receiver comprises the first infrared receiver, the second infrared receiver and the 3rd infrared receiver that level is equidistantly placed, and the first infrared receiver, the second infrared receiver and the 3rd infrared receiver and the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit receive the infrared ray that the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit are launched respectively.By arranging multiple infrared emission unit and infrared receiving unit, can repetitive measurement be passed through, ensureing the accuracy of data.When part infrared emission unit and infrared receiving unit damage, can also not affect the measurement to sheet metal thickness simultaneously.
Preferably, infrared emission unit be arranged on distance entrance keep at a certain distance away across on the support 10 of driving-belt, infrared receiving unit is arranged on the entry position of casing, and level is corresponding respectively for the first infrared receiver, the second infrared receiver and the 3rd infrared receiver and the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit.
Preferably, infrared receiving unit be arranged on distance entrance keep at a certain distance away across on the support 10 of driving-belt, infrared emission unit is arranged on the entry position of casing, and level is corresponding respectively for the first infrared receiver, the second infrared receiver and the 3rd infrared receiver and the first infrared emission unit, the second infrared emission unit and the 3rd infrared emission unit.
Certainly, Fig. 4 show only the schematic diagram of Fig. 1 embodiment thickness setting checkout gear, and the embodiment in Fig. 2 also can thickness setting checkout gear, and those skilled in the art can be able to obtain according to description, is not just drawings illustrating further.
Although the present invention discloses as above with preferred embodiment, the present invention is not defined in this.Any those skilled in the art, without departing from the spirit and scope of the present invention, all can make various changes or modifications, and therefore protection scope of the present invention should be as the criterion with claim limited range.