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About Huakai

Production equipment

                                   PVB film production equipment             

Cone mixer

Working principle: two asymmetric helical rotation in the cone mixer barrel lifts the material upward, and the rotating arm moves slowly around; The material outside the spiral enters the stud to different degrees, so as to achieve the continuous update and diffusion of the material in the whole circumference. The two materials mentioned above then converge to the central recess, forming a downward material flow and filling the vacancy at the bottom, thus forming the triple mixing effect of convection circulation. Standard conical screw mixer has two stirring screws. In practical application, single screw (one long screw), double screw (one asymmetric screw of each length) and three screw (two short screw and one long screw arranged symmetrically) can be used according to equipment specifications. In theory, the more screw stirring, the better mixing effect; The device generally adopts the plum shaped "dislocation valve", which is closely fitted to the bottom of the long screw to effectively reduce the mixing dead Angle. Butterfly valve, ball valve, star unloader, side discharge can also be installed according to the user's needs.Performance characteristics: according to the process requirements, the cone mixer can be added to the outside of the mixer barrel jacket, by injecting cold and hot media into the jacket to achieve the cooling or heating of the material; Cooling generally pumped into industrial water, heating can be steam or electric heating heat conduction oil. The conical cylinder is suitable for the high requirement of no residue of mixed materials. Gentle stirring speed will not damage fragile materials. The stirring action of the machine has a better coordination effect to the chemical reaction of materials.

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Single screw extruder

Single screw extruder is mainly used for extruding soft, hard polyvinyl chloride, polyethylene and other thermoplastic plastics, can process a variety of plastic products, such as blowing film, extrusion tube, pressing plate, wire drawing, can also be used for melting granulation.

Principle of single screw extruder:

The first paragraph is called transmission materials, and can't plasticizing here; but to preheating, squeezing the reality, the past old extrusion theory is that the material is loose, then by showing that the material is actually a solid plug, that is to say here after squeezed a solid material like the plug, so as long as the delivery task is the function of it.

The second section is called compression section, when the screw slot volume gradually decreases by large, and the temperature should reach the degree of material plasticization, compression is generated here by conveying section three, compression here, this is called screw compression ratio -- 3:1, plasticized material into the third section.

The third section is the measurement section, where the material to maintain the plasticizing temperature, just like the metering pump as accurate, quantitative transfer of melt material to supply the head, at this time the temperature can not be lower than the plasticizing temperature, generally slightly higher.

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Single screw extruder structure and location of main components

1- flange; 2 -- shunt plate; 3 - screw; 4 -- cooling water pipe; 5 -- heater; 6 - barrel; 7 -- gear pump; 8,10 -- motor; 9 - bearing; 11 - hopper; 12 -- gear reduction box; 13 -- swivel joint; 14 - V belt wheel; 15 -- motor; 16 - reduction box body; 17 - stand; 18 - hood

Net changer

A mesh changer is a manual or automatic switch consisting of one or more filters to remove foreign particles and impurities as the plasticizer passes through the mesh. The screen is supported by an alloy porous plate mounted on a plate-type or column-type carrier that can be moved to switch between a system's working position and off-line non-working position. Net changer can be installed on any new or existing extruder, melt pump, reactor or other extrusion line. It can be used to filter any type of polymer, rubber or ceramic melt.

PVB products special non - stop net changers such plastic products outstanding characteristics are high transparency, high precision and relatively high molding temperature. The special screen changing appliance has the following features:

(1) there is a "spot" exhaust mechanism and flow channel, when changing the net can exhaust the gas in the new net to maintain the net pressure balance, thoroughly solve the problem of "bubble".

(2) the exhaust position is also the preheating position of the mesh block at the same time, which can ensure that the network to be replaced is consistent with the network temperature to be replaced, avoiding the low temperature of the new mesh block which leads to the crystallization of molten material and then the flow becomes poor or even crystal point.

(3) the ordinary net changer is the filter (porous plate) carrier directly in contact with the plastic melt, because the net needs to move back and forth friction, which is easy to produce black spot impurities, filter clean no matter how clean, because can not directly clean the carrier. And special mesh changer is not the same: the filter (porous plate) and carrier into a whole into a mesh block, and let it circulation one-way movement, to avoid the production of black spot impurities, and after the net can be taken to clean up, clean mesh block is installed on the new filter net no black spot impurities.

(4) PET has excellent fluidity. In order to maintain the stability of the rigid mechanical seal of the mesh changer, the steel used in the mesh changer is wear-resistant and heat-resistant, and the flow channel is smoother than that of the general mesh changer.

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The melt pump

Melt pump is mainly used for conveying, pressurizing and measuring high temperature and high viscosity polymer melt. Its main function is to supercharge and stabilize the high temperature melt from the extruder, to keep the melt flow accurate and stable into the extruder head. Direct metering control can be realized to eliminate the impact of extruder fluctuation and screw on the die head. The extruder can effectively extrude the melt and the mixing technology to send the resin material, but not effectively enough to provide the melt of the die head with constant pressure and volume. Melt pump can effectively supercharge the melt and accurately measure the melt.

Benefits of polymer extrusion using melt pumps:

(1) improved dimensional stability -- effectively isolated the die head from pressure fluctuation from upstream, and minimized dimensional tolerance of extruded products.

(2) control the melting mass -- adjust the back pressure of the extruder to reduce the retention time, stabilize the plasticizing effect, and reduce the melting temperature. (3) increased output -- reduced the pressure requirements on the screw, from the original screw to the die head pressure, melt pump to the die head pressure, screw can be high speed and efficient extrusion, regardless of the size of the pressure required to provide a very high efficiency.

(4) reduce the use of raw materials -- extrude the final product with small size change, reduce scrap and scrap rate.

(5) eliminate the fluctuation and screw shock -- effectively solve the pressure fluctuation caused by melt density or extruder parameters.

(6) increased the flexibility of the extruder, allowing for changes in processing conditions, such as higher recycling volume, temperature and pressure, etc.

(7) reasonable operation and operation -- pressure closed-loop control, PLC or intelligent instrument.

(8) extend the service life of the extruder -- reduce the extrusion pressure of the extruder, reduce the work intensity of the extruder, can greatly delay the wear of the screw and screw barrel, and extend the life of the extruder.

(9) low operating cost -- more accurate conveying measurement is provided to avoid waste of raw materials.

 

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