I. what is a blow molding machine
Blow molding machines, also known as hollow blow molding, are a rapidly developing plastic processing method. A blow molding machine is a machine that blows liquid plastic out and uses the wind blown out of the machine to blow the plastic body into a mold cavity of a certain shape to make a product. The plastic is melted and quantitatively extruded in a screw extruder, then formed by mouth film, then cooled by air circulation, and then a tractor pulls at a certain speed, and the winder winds it into a roll.
II. Types of blow molding machines
Blow molding machines can be divided into extrusion blow molding machines, injection blow molding machines, and special structure blow molding machines.
Extrusion blow molding machine: Jwell blow molding machine is a combination of an extruder, blow molding machine and clamping mechanism. It consists of an extruder and mold head, blowing device, mold closing mechanism, billet thickness control system, and transmission mechanism. Billet dies are important components that determine the quality of blow-molded products. There are usually side-feed dies, and center feed dies. Storage cylinder type billet die mostly used for blow molding of large products. The minimum volume of the storage cylinder is 1kg, and the maximum can reach 240kg. The billet thickness control device controls the bad wall thickness, with control points up to 128 points, generally 20 to 30 points. JWELL blow molding machine can produce hollow products with a volume range of 25m1~1041.
Injection blow molding machine: It is a combination of injection molding machine and blow molding mechanism, including plasticizing mechanism, hydraulic system, control appliance, and other mechanical parts. Common types are three-station injection blow molding machines and four-station injection blow molding machines. The three-station device has three stations for prefabricated blanks, blowing, and demoulding. Each station is 120° apart, and the four-station machine has one more performed station, and each station is 90° apart. In addition, there are double-station injection blow molding machines 180 stations apart. The plastic container produced by the injection blow molding machine is precise in size and does not require secondary processing, but a high mold cost.
Special structure blow molding machine is a blow molding machine that blows hollow bodies with special shapes and uses sheets, molten materials, and cold blanks as blanks. Due to the different conditions and requirements of the products produced, the structure of the blow molding machine also varies.
III. Production process of jwell blow molding machine
The extrusion blow molding process consists of 5 steps:
- Plastic embryo (extrusion of hollow plastic pipe).
- JWELL blow molding machine closes the flap mold on the mold embryo, clamps the mold, and cuts off the mold.
- Blow to the cold wall of the mold cavity, adjust the opening and maintain a certain pressure during cooling.
- Open the mold and write down the blown parts.
- Trim the flying edge to get the finished product.
Ⅳ. Basic principles of JWELL blow molding machine
The automatic air ring structure of JWELL blow molding machine adopts dual air outlet mode, in which the lower air outlet air volume remains constant, the upper air outlet is divided into several air ducts on the circumference, each air duct is composed of an air chamber, valve, motor, etc.
In the control process of the JWELL blow molding machine, the thickness probe detects the film’s thickness and transmits it to the computer. The computer compares the thickness signal with the current set average thickness, calculates according to the thickness deviation and the curve change trend, and controls the motor drive valve to move. By changing the air volume of each point on the circumference of the wind ring and adjusting the cooling speed of each issue, the lateral thickness deviation of the film is controlled in the target range.
Ⅴ. Main start-up preparation of jwell blow molding machine
The cooling water of the cooling barrel must be fully opened to avoid the occurrence of screw gnashing.
Preheat the hydraulic oil. If the hydraulic oil temperature in the hollow blow molding machine oil tank of JWELL blow molding machine is too low, the heater should be turned on immediately.
Press the start button to stop immediately and check whether the pump is running in the correct direction. If it is found that it does not correspond, directly change the power cord of the two-phase induction motor.
The opening of the JWELL blow molding machine should be carried out without pressure in the hydraulic system. When turned on, adjust the pressure of the relief system of each pump to the safety pressure. There are often two pressure systems; one is a mold closing unit, and the other is a blow molding unit, and each team has a pressure vent valve. This pressure relief valve must be opened after the pump is stopped, and when the pump is working, the pressure relief valve must be closed.
Adjust the position of all the stroke switches so that the moving template remote switch is smooth.
Close the door completely. According to safety protection requirements, all safety doors should be closed when the machine is working. For large hollow blow molding machines, opening the safety gate and closing movement will be stopped, and the oil pump will stop if another safety gate is opened.
Turn on the heating and temperature control system.
Install the mold. The mold surface and the contact surface with the hollow blow molding machine template must be cleaned when installing the mold.
Ⅵ. Precautions for the shutdown of jwell blow molding machine
- Each speed is reset to zero during the shutdown, and each heating section is shut down one by one.
- Close the mold in a closed state, blow the needle half a centimeter away from the mold to prevent hard objects from falling into the decay and causing damage to the mold.
- Anti-rust treatment of the mold: If the downtime is long, it is necessary to keep the water inside the mold clean to prevent rust and clogging.
- Turn off the main power supply of JWELL blow molding machine, lubricate and maintain the equipment, add lubricating oil, clean the whole machine hygienically, and turn off the water strings.
- The screw inlet should be covered with textile or cloth to isolate debris, air and moisture.