CN110014637A - A down blowing water-cooled film blowing device - Google Patents

Abstract

The invention discloses a bottom blowing water-cooling film blowing device, which mainly includes a plasticizing mechanism, a film blowing mechanism, a frame, a cooling mechanism, a cutting mechanism, a traction mechanism and a winding mechanism. The plasticizing mechanism, cutting mechanism and winding mechanism are located on the ground, the film blowing mechanism is located on the frame, and the cooling mechanism and the pulling mechanism are located in the water tank under the ground. The material is melted and plasticized by the plasticizing mechanism and enters the film blowing mechanism on the left side. The film blowing mechanism blows the material into a film and enters the cooling mechanism below for cooling. The cutting mechanism cuts the film as it enters the cooling mechanism. The cooled film is guided by the pulling mechanism and finally wound by the winding mechanism. The downward blowing water-cooling film blowing device proposed by the present invention is suitable for the production of large-folded diameter and ultra-wide films. The water in the water tank in the device of the present invention can be kept in a constant temperature state through the circulation of the water pump. Due to the downward pulling of the membrane tube, the self-weight fracture of the membrane will be greatly improved. The performance of the shaped film is greatly improved compared with that of the film produced by the traditional process.

Description

A down blowing water-cooled film blowing device

technical field

The invention relates to the field of blown film forming and is used for down blowing water cooling to produce PVC film.

Background technique

Blown film is one of the most widely used forming methods in the production of plastic films. The top blowing method is commonly used in production. The actual production has the following problems: (1) In summer, the workshop temperature is high, the traction direction is the same as the heat flow direction, and the cooling effect is not good. (2) Because the frame is too high, the self-weight fracture of the membrane tube is easy to occur. (3) After the membrane tube passes through the herringbone, the membrane strength is not enough and the fracture will occur. In order to solve the above problems, the down-blown water-cooled film blowing method is proposed. It avoids the self-weight fracture of the film caused by upward blow molding, and the cooling effect is also greatly improved compared with the upward blow method. The cooling system of the traditional down-blowing water cooling method mostly adopts the water ring spray method or the device method in the membrane tube. After searching, the Chinese patent discloses a cooling water ring for down-blown film [application number CN201610447228.4], which has the advantage of uniformly distributing cooling water on the film bubble, improving the cooling effect and improving the quality of the film. A circulating water cooling device in a film tube of a film blowing machine [application number CN201210345991.8] has the advantages of simple structure and fast cooling speed.

With the actual needs of people's production, ultra-wide and large-folded films have been proposed. Due to the characteristics of ultra-wide and large-diameter films: the diameter of the film bubble is large and the height is long (the height of the film with a 24m-folded diameter is more than 10m), efficient heat dissipation has become the first factor to be considered. For the production of large-diameter films, the traditional down-blowing water-cooling device has the following disadvantages: (1) In the production of large-diameter films, the distance from the film bubble to the water ring is long, and the air flow in the workshop causes the water sprayed out by the water ring. The cooling water cannot be evenly distributed, and the quality of the film bubble will be greatly reduced; (2) the traditional down-blowing water cooling mostly focuses on the structural optimization of the water ring, the die head, and the device in the film. The introduction of compressors, pumps and other equipment makes the device more and more complicated. If the traditional production method is used in the production of large-diameter films, the volume requirements of the moving equipment are high, and the cost will increase accordingly; (3) For large-diameter films (4) For the spring and summer seasons, the traditional down-blowing water cooling device, the membrane tube is exposed to the air, and the temperature of the membrane tube in the two seasons is quite different. Great impact on the production process.

SUMMARY OF THE INVENTION

The purpose of the present invention is mainly to propose a new type of downward blowing water cooling device for the production of ultra-wide and large-folded diameter films, so as to solve the problems raised by the above background.

The invention is realized by the following technical solutions: a bottom blowing water-cooled film blowing device mainly includes a plasticizing mechanism, a film blowing mechanism, a frame, a cooling mechanism, a cutting mechanism, a traction mechanism and a winding mechanism. The plasticizing mechanism, cutting mechanism and winding mechanism are located on the ground, the film blowing mechanism is located on the frame, and the cooling mechanism and the pulling mechanism are located in the water tank under the ground. The material is melted and plasticized by the plasticizing mechanism and enters the film blowing mechanism on the left side. The film blowing mechanism blows the material into a film and enters the cooling mechanism below for cooling. The cutting mechanism cuts the film as it enters the cooling mechanism. The cooled film is guided by the pulling mechanism and finally wound by the winding mechanism. The plasticizing mechanism includes a twin-screw extruder. The extruder melts and plasticizes the material, and the melted material is extruded through the gap of the annular die of the die. One side of the plasticizing mechanism is provided with a film blowing mechanism. The film blowing mechanism includes a machine head, an air ring, and a pressure sensor. The film blowing mechanism blows the extruded film tube to a high elastic state, and leads the film tube vertically to the cooling mechanism below. The frame is located below the ground, and is characterized in that a film blowing head and an air ring are installed on a flat plate above the frame. The cooling mechanism includes a constant temperature water tank and cooling water. It is characterized in that the constant temperature water tank is located below the level ground, which can control the height of the water level and the temperature of the cooling water. The film blown out by the film blowing mechanism is cooled by a constant temperature water tank. The cutting mechanism includes a hydraulic device, a cutting knife and a knife groove, and is characterized in that the hydraulic device pushes the transmission element to move back and forth through the hydraulic cylinder actuator, the transmission element drives the knife groove to rotate, and the cutting knife can move in the knife groove. When the membrane tube passes through the water tank, the water pressure in the water tank gradually increases, and the membrane tube in the water tank will be flattened due to the pressure difference between the inner gas and the outer water pressure. At this time, the hydraulic device drives the cutting knife to move, and the cutting knife When cutting the film in the water tank, the pressure of the cooling water is greater than the air pressure in the film tube, so that the cooling water enters the film tube and ensures the internal and external pressure balance of the film tube. The traction mechanism of the film includes a winding roller and a traction roller, and the winding roller and the traction roller are fixed inside the constant temperature water tank. The rolling roller flattens the cylindrical film tube, and the formed film is then taken up by the traction roller and pulled to the winding mechanism above the ground. The rewinding mechanism is located on the left side of the ground. The blown film tube is wound by the pulling device, pulled to the ground, and then automatically wound by the winding device.

The working flow of the downward blowing water-cooled film blowing device of the invention is as follows: the material is placed in the feeding port of the extruder, the material is melted and plasticized, and extruded under the action of the die of the die. The film blowing mechanism blows the extruded material into a film tube, and the film tube reaches a state of equilibrium vertically downward under the action of gravity and the compressed air in the machine head. The membrane tube enters the constant temperature water tank and is cooled by cooling water. Due to the unbalanced pressure difference between the inside and outside of the membrane tube, the membrane tube in the water tank will sag inward. At this time, the hydraulic device drives the cutter to cut the membrane tube below the water surface, and the water outside the membrane tube will enter In the membrane tube, the internal and external pressures are kept balanced, and the sunken membrane tube returns to its original state. The film tube is extruded into a film by the winding roller, and is wound up by the winding device drawn by the traction roller to the ground.

A water-cooled spray device can be added near the machine head.

The invention is a bottom blowing water-cooling film blowing device, which can add an appropriate amount of ethylene glycol to the water in winter, the water temperature can be lower, and the freezing can be prevented. In addition, cooling pipes (with compressors) and heating pipes can be provided outside the water tank to control the temperature of the cooling water.

The invention is a bottom blowing water-cooling film blowing device, which is suitable for the production of large folded diameter and ultra-wide films. The beneficial effect is that (1) the water in the water tank can be kept in a constant temperature state through the circulation of the water pump. After the film tube extruded by the extruder is cooled by the cooling water in the water tank, the surface temperature of the film can be kept constant and low. (2) Due to the downward traction of the film tube, the self-weight fracture of the film will be greatly improved. The performance of the shaped film is greatly improved compared with that of the film produced by the traditional process. (3) The blown film device is located below the ground, and the construction cost of the workshop will be greatly reduced. (4) The temperature of the film tube is not much different in the four seasons, which has little impact on the production process.

Description of drawings

FIG. 1 is a schematic diagram of a bottom blowing water-cooled film blowing device of the present invention.

FIG. 2 is a schematic diagram of a hydraulic device and a cutting device of a down-blowing water-cooled film blowing device of the present invention.

3 is a schematic diagram of the state of the film before and after cutting in a water tank of a water-cooled film blowing device for downward blowing of the present invention.

In the picture: 1—extruder, 2—head, 3—frame, 4—air ring, 5—winding device, 6—film, 7—traction roller, 8—constant temperature water tank, 9—roller, 10 - Cutting knife, 11 - Knife groove, 12 - Hydraulic device, 13 - Transmission element.

Detailed ways

A bottom blowing water-cooled film blowing device of the present invention, as shown in Figure 1, mainly includes a plasticizing mechanism, a film blowing mechanism, a frame, a cooling mechanism, a cutting mechanism, a traction mechanism and a winding mechanism. The plasticizing mechanism, cutting mechanism and winding mechanism are located on the ground, the film blowing mechanism is located on the frame, and the cooling mechanism and the pulling mechanism are located in the water tank under the ground. The material is melted and plasticized by the plasticizing mechanism and enters the film blowing mechanism on the left side. The film blowing mechanism blows the material into a film and enters the cooling mechanism below for cooling. The cutting mechanism cuts the film as it enters the cooling mechanism. The cooled film is guided by the pulling mechanism and finally wound by the winding mechanism. The plasticizing mechanism includes a twin-screw extruder 1 . The extruder 1 melts and plasticizes the material, and the melted material is extruded through the gap between the annular die of the die head 2. One side of the plasticizing mechanism is provided with a film blowing mechanism. The film blowing mechanism includes a machine head 2, an air ring 4, and a pressure sensor. The film blowing mechanism blows the extruded film tube to a high elastic state, and leads the film tube vertically to the cooling mechanism below. The frame 3 is located below the ground, and is characterized in that a film blowing head 2 and an air ring 4 are installed on a flat plate above the frame 3 . The cooling mechanism includes a constant temperature water tank 8 and cooling water. It is characterized in that the constant temperature water tank 8 is located under the horizontal ground, and can control the height of the water level and the temperature of the cooling water. The film 6 blown out by the film blowing mechanism is cooled by a constant temperature water tank 8 . As shown in FIG. 3(1), the film in the cooling water sags due to the unbalanced internal and external pressure. During the process of the film tube 6 passing through the water tank 8, the water pressure in the water tank 8 gradually increases, and the film tube 6 in the water tank 8 will Because of the pressure difference between the inner gas and the outer water pressure, it is squashed, as shown in Figure 3 (2), at this time, the hydraulic device 12 drives the cutting knife 10 to move, the cutting knife 10 cuts the film 6 in the water tank 8, and the cooling water The pressure is greater than the air pressure in the membrane tube 6, so that the cooling water enters the membrane tube 6, and the internal and external pressures of the membrane tube 6 are ensured to be balanced. As shown in FIG. 2, the cutting mechanism includes a cutting knife 10, a knife groove 11 and a hydraulic device 12, which is characterized in that the hydraulic device 12 pushes the transmission element 13 to move back and forth through the hydraulic cylinder actuator, and the transmission element 13 drives the knife groove 11 to rotate. , the cutting knife 10 can move in the knife groove 11 . The traction mechanism includes a traction roller 7 and a winding roller 9 , and the traction roller 7 and the winding roller 9 are fixed inside the constant temperature water tank 8 . The cylindrical film tube 6 is flattened by the winding roller 9, and the formed film 6 is then taken up by the pulling roller 7 and pulled to the winding device 5 above the ground. The rewinding device 5 is located on the left side of the ground. The blown film tube 6 is taken up by the pulling device 5 , pulled to the ground, and then automatically wound by the winding device 5 .

When the device is working, the material is first placed in the feed port of the extruder 1, the material is melted and plasticized, and extruded under the action of the die 2 of the die. The film blowing mechanism blows the extruded material into a film tube 6, and the film tube 6 reaches a state of equilibrium vertically downward under the action of gravity and the compressed air in the machine head 2. As shown in FIG. 3 , the membrane tube enters the constant temperature water tank 8 and is cooled by cooling water. Due to the unbalanced pressure difference between the inside and outside of the membrane tube 6, the membrane tube 6 in the water tank 8 will sag inward. At this time, the hydraulic device 12 drives the cutter 10 to cut the water surface. In the membrane tube 6 below, the water outside the membrane tube 6 will enter the membrane tube 6 to maintain the internal and external pressure balance, and the depressed membrane tube 6 will return to the initial state. The film tube 6 is extruded into a film by the winding roller 8, and is wound up by the winding device 5 drawn to the ground by the pulling roller 7.

Claims (3)

1. a kind of downward-blowing water-cooling blown film device, mainly include plastifying organization, blown film mechanism, rack, cooling body, cutting mechanism, Traction mechanism and rolling-up mechanism, it is characterised in that: plastifying organization, cutting mechanism and rolling-up mechanism are rest on the ground, blown film mechanism In rack, cooling body and traction mechanism are located in sink below ground；Material via plastifying organization fusion plastification into Enter the blown film mechanism in left side, material is blown thin film forming by blown film mechanism, and the cooling body for entering lower section is cooling；Cutting mechanism is thin Cutting when film enters cooling body；Film after cooling is guided by traction mechanism, is finally wound by rolling-up mechanism；The inflation film manufacturing machine Structure includes head, vane, pressure sensor, and blown film mechanism vertically guides to the membrane tube inflation of extrusion to elastomeric state, and by membrane tube The cooling body of lower section；The rack is located at below ground, and rack upper plate is equipped with the head and vane of blown film, described Cooling body includes thermostatic water bath, cooling water, and thermostatic water bath is located at below level ground, can control the height of water level and cold But the temperature of water；Traction mechanism described in film includes winding up roller and traction roller, and winding up roller and traction roller are fixed on inside thermostatic water bath； The rolling-up mechanism is located at ground left side of face, and the membrane tube of blowout is batched by traction device, drawn to ground, then certainly by wrap-up Dynamic winding.

2. a kind of downward-blowing water-cooling blown film device according to claim 1, it is characterised in that: the cutting mechanism includes hydraulic Device, cutter and cutter groove, hydraulic device push actuated element to move forward and backward by hydraulic cylinder executive component, and driving member drives Cutter groove rotation, cutter can move in cutter groove.

3. a kind of downward-blowing water-cooling blown film device according to claim 1, it is characterised in that: add suitable second two in water Alcohol, or cooling tube and heating tube are set for controlling the temperature of cooling water outside sink.