Mixing is indispensable to modern industrial production process, with the continuous development of China's industry, the development of the hybrid system and the equipment will be stronger and stronger.Mixed covered the entire industrial sectors, such as chemical industry, food, building materials, medicine, chemical fertilizer, products we use every day all the time at least one step mixing process in the production.
An overview, blending and mixing machine
Mix refers to the two materials and two or more physical activities together, without any chemical change.
Including their mix and mechanical mixing.Their movement between mixed refers to material, through mixing friction by oneself;Mechanical mixing refers to the materials by mechanical force effect after mixing.General gas for their mix;3 d mixing equipment for their mix and a combination of mechanical mixing;All mixed containers don't exercise in the mix for mechanical mixing.
Mixing equipment quality evaluation according to the different physical quantities.
Mixed uniformity: ginseng to stand or fall of physical quantity analysis material, through the theory of probability, mixing uniformity is determined by mixing equipment types.
Corner: refers to the material in a mixed container can't participate in the combination of physical phenomenon, corner percentage is mixing equipment manufacturing quality evaluation of physical quantities.
Mixing time: evaluation of mixing speed of physical quantities, refers to the different material began to mix to achieve uniformity requirements within the time, mixing time is determined by mixing equipment types and models.
Second, the selection of dry powder mixing equipment
There are many types of dry powder mixing equipment, this paper mainly on the Chinese market at present commonly used in the mechanical mixing equipment equipment double helix cone mixer, horizontal zero gravity mixing machine, horizontal colter mixer, horizontal ribbon mixer for analysis:
1, the double helix cone mixer
Mixed type space is an inverted cone, barrel body has two, three, or a single spiral shaft's rotation and orbit along the barrel wall, under the condition of motor reducer with the top of the power unit at the mixer.
Hybrid material applicable scope is big, the hybrid material density deviation, size deviation is not very strict, easy to control the material of friction heat or static electricity
Mixed material of crystal damage small.
When mixed equipment low power requirements, the same type of equipment motor power is reduced greatly.
Equipment model can be extended to large, China's domestic with 30 cubic greatly.
Mixing time is relatively long, but large equipment manufacturing into three spiral form, can greatly shorten the mixing time.
Main application and powder mixed with powder, can be blended in when the water in the material into a lot of liquid, but mixed in the whole process of material in the form of solid powder, application cases of dye, monosodium glutamate, additives, such as plastic particles.
2, horizontal zero gravity mixing machine
Hybrid space for twin u-shaped barrel horizontal form, there are two barrels in the horizontal shaft, shaft with a blade arm, two mixing shaft rotate along the opposite direction, motor reducer in the side of the main equipment.
Mainly for the powder, mix between particles, for the mixing of materials is not adapted to the light
When mixed with the material for a wide range of sports, damage to the material of crystal have small range.
Equipment mixed all materials are in motion, high power demand is high.
Mixing time is fast in mechanical mixing equipment.
Chinese domestic with 20 cubic.
Mainly used mixed with powder and powder, mixed material can be a form of particles, can be blended in when the water in the material into a small amount of liquid, but mixed in the whole process of material in the form of solid powder, dry mortar application example, salt, chemical fertilizer, etc.
3, horizontal colter mixer
Hybrid space for barrel horizontal form, the barrel body one stripe coulter horizontal axis;On the side of the barrel with a large number of high speed, and the main mixing shaft into 90 degrees, motor reducer in the end face of the main equipment.
When mixed with high-speed movement, to material of crystal have much damage.
With the power requirements, mixed with time.
Chinese domestic with 20 cubic.
Main application and powder mixed with powder, mixed material can take a small amount of short fiber, can be blended in when the water in the material into a small amount of liquid.Application cases of building materials, fiber dry powder mixing, etc.
4, horizontal ribbon mixer
Hybrid space for u-shaped barrel horizontal form, there is a whole bucket body screw shaft.The motor reducer in the end face of the main equipment.
Blend smoothly, to the destruction of the crystal effect is small.
When mixed equipment all materials in the whole motion, high power requirements.
Relatively short mixing time.
Main application and powder and powder or mixed with sticky materials, can be blended in when the water in the material into a lot of liquid, mixing material body can be reflected in the whole process of solid powder can also reflect a viscous, application cases of thickening powder, gray surface, coating etc.
Three, selection of mixing equipment size
Mixing equipment in terms of size, the current domestic do 30 cubic, a leading producer for Shanghai, zhejiang, sichuan province.Mixing process and the requirement of hybrid, mixing equipment can be divided into experimental 0.05 ~ 0.5 cubic;0.5 ~ 6 cubic production;Batch type 4 ~ 30 cubic;
Experimental equipment
Production ability request is not high, mainly at the early stage of the enterprise investment experiment and pilot production.
Production equipment
High production capacity, it is mainly for the enterprise investment products, such relative strength design of the equipment are high, there is no power requirements, cooperate with other production equipment, including the ingredients, automatic feeding, automatic discharging, manufacture a complete set of mixed production line, production efficiency is high, the investment is relatively low.According to the production requirements, a set of production lines of one or two products, do not need to replace the product for a long time form, implements the assembly line equipment, instead of the big production need to select equipment technical requirements.
Batch type equipment
Mainly used in places mixed batch is very strict, such as dyestuff, food, etc.With a batch of goods should not be under the special requirements such as color, taste the difference.
Four, mixed the choice of auxiliary functions
For the mixing of materials according to the requirements of the different mixing process, need different hybrid method and the environment.Mixing equipment according to the different ways of mix design a lot of mixed auxiliary function, according to the requirements of the different hybrid choose different auxiliary functions.
Heating or cooling
In the process of material mixing, heating is a common phenomenon.
(1) mixing process of some material need to be realized in a certain temperature conditions, can satisfy the raw material can be mixed, can improve the uniformity of mixing.
(2) some mixed material itself contains certain moisture, can by raising the temperature in the process of mixed water drying, such as simple solution to implement a simple mixing, drying step function.
For mechanical dry powder mixing equipment, heating or cooling in the casing mixing vessel, ensure the mixing vessel inner at a constant temperature in the process of mixing, mixing machine insulation is the main way, the traditional call for jacketed.
According to the requirements of the different temperature, the common heating mode are: (1) inside the jacket to join the heat conduction oil, direct heating thermal oil heating wire (2) circulating oil heating (3) heating steam cycle
Heating jacket in order to improve the efficiency of energy utilization, the shell need to do a layer of heat preservation, avoid heat to the air.To coincide with the heating requirements for mixing process, equipment, general need auxiliary boiler or other energy equipment.To eliminate mixed in the process of heating steam or other material, system also needs a set of system for wind and dust removal system.
Vacuum or pressurized
May oxidation in the process of mixing, or other material will not be able to in the process of air condition to complete, you need to vacuum mixing equipment container, when necessary inert gas protection is needed.
spray
In order to meet the dry powder to join a small amount of fluid in the mixing process, at the same time must improve liquid and powder mixing uniformity, liquid needs to be in contact with the powder spray pattern.
When we mixed ash surface, for example, if the water, grey surface after loading container again by mechanical mixing together, it is hard to mix;If the gray surface mechanical movement let water in fog and grey surface contact, will greatly improve the mixing uniformity and mixed time.
Fly knife device
Hybrid material if there is a fiber or other difficult to disperse in the material, high-speed mixing process to disperse, mixing equipment requires the design and manufacture of high speed rotating shaft.
Five, selection of auxiliary equipment
Mixer is the core of the mixing process.In order to improve the speed and mix of process automation, mixing machine needs to be equipped with other auxiliary equipment, meet the mixed process as a whole.Conventional mechanical mixing equipment works are intermittent operation, single batch mixing materials need to be ready to join mixer, mixing and discharge
Feeding equipment to improve the clearance and mixing time, the need to quickly join mixer mixing material prepared at a time.In order to prepare a material for each need to mix, can design manual batching or automatic batching.
Feeding equipment
Mixer discharge according to the different forms, different process has a different way.But no matter what form, the mixed material need to step in a bin or under the other process equipment, etc.
Mixer valve according to different operation requirements have different options:
According to the discharging valve forms are gate valve, butterfly valve, ball valve, rotary valve, gate valve, valve, arc valve.
According to the operation way of discharging valve with manual, electric, pneumatic control.
Mixing machine selection: powder mixed operation is very complex, especially due to the nature of the powder mixed effect of shape ring is very large.So the more large mixed pause type field difficult.So the selection of mixing machine, in addition to the African palm to catch the above general principles, further grasp the general selection method of in general.Selection method are: the analogy method, small test, test, analogy method
Users according to their own material, reference to peer manufacturers choose models.Can quickly select the mixing machine models.This method has the advantage of the method is simple.Spending less in the selection process.With others' experience for reference, so the correctness of the model selection is larger, less mistakes.Drawback is that the market competition is fierce, sometimes counterparts ask technical secret, it is hard to understand to the exact circumstances.
A small test
Users are able to quote according to their own material.Refer to the manufacturer's product manuals and other documents.Preliminary model test in selected face to try.In the small mixer of assorted to be measured can state of mixing, mixing uniformity, etc.
In small, we can choose light several mixer were contrast experiment.Then according to the following principles, selected mixer: (1) mixing uniformity and the time needed for mixing;(2) comprehensive comparison of equipment cost, energy cost, maintenance cost and handling fee sichuan;(3) the installation conditions, such as for space and power limit.According to the results of test analysis.Determine the model.As for the selected product and dissatisfaction with the place, to broad party request correction.Make it more suitable for production requirement.
In the test
In large type no alternative.Sometimes just rely on test results is not enough.For pilot, validation is the purpose of the pilot test results, at the same time provide further basis for selection.When the pilot should pay attention to the following son points:
The bigger 1, test equipment and the closer to the use of large equipment, the test results can be more reliable.
2, due to the powder mixing machine amplification published data.So when the pilot should work closely with manufacturers, more general pilot (enlarge) the operation of the data provided by the manufacturer or structure improvement.Wipes the pilot process, should also focus on the mixing uniformity, power change, mixing time and mixing of libel, start on such issues.Only after the pilot result is consistent with the test results.Further equipment selection have reliable basis
3, pilot, the material should be used as a given process, consistent with the kind of material.
Selection is accurate, the advantage of this method is: in the future production, product production, can fully guarantee, mixing time, energy, equipment costs can be controlled within the scope of the better.Lack of us is: the equipment for a long time.The amount of manpower and material resources.