1. Principle of wire extruder:
A. Using screw rotation to shear the rubber material and make it flow from the feed port towards the machine head;
B. The feeding area of the extruder preheats the rubber material and continuously transports the raw material forward, while removing moisture from the material during this process;
C. The compression zone mainly heats up the raw materials pushed from the feeding zone to fully gelatinize the rubber material and fully mix it, so as to enrich the composition of the rubber material;
D. The metering area mainly further mixes the raw materials in the compression area to make the rubber material more uniform, ensuring that the rubber material is pushed forward at a constant volume and pressure;
E. The porous plate mainly changes the material flow from rotation to linear flow, and supports the filter screen to filter the unmelted rubber particles and impurities in the rubber material. At the same time, it increases the internal pressure of extrusion, thereby achieving full melting of the rubber material during its retention time in the machine barrel;
F. The material flow is divided through the machine head and the diameter is extruded into the desired shape by the mold;
2. The extruder is set at different temperatures due to different materials used. The following are the processing temperatures for various extrusion materials:
A. PP and PE materials are generally extruded at temperatures between 150 ℃ and 230 ℃ in each section;
B. PVC core wire materials are generally extruded at temperatures between 130 ℃ and 190 ℃ in each section;
C. PVC outer coating is generally extruded at temperatures between 120 ℃ and 160 ℃ in each section;
D. PU materials are generally extruded at temperatures between 150 ℃ and 220 ℃ in each section;
3. How to choose the inner and outer molds when extruding wire?
A. Principles for selecting internal molds:
a. The extrusion of the internal mold depends on the total outer diameter of the copper wire or core wire (total outer diameter=number of pieces) × one point one five × Single outer diameter);
b. It is advisable to extrude the inner mold of the core wire with a total outer diameter of+0.1mm;
c. The PVC outer inner mold should have a total outer diameter of+0.4mm-0.6mm (depending on the effect of core wire assembly. If the core wire is round, the inner mold should be smaller, and if the core wire is not round or cotton paper is added, a larger inner mold should be used);
B. Principles for selecting external molds:
a. PP and PE materials should have a finished outer diameter of+0.4mm, while PVC materials should have a finished outer diameter of+0.05mm;
b. When PVC is extruded, the outer mold is selected to have a finished outer diameter of+0.3-0.5mm;
Note: When PVC is extruded, the selection of the outer mold is greatly influenced by the core wire structure and the completed outer diameter;
4. How to adjust the wire deviation?
A. The reason is that the locking sleeve is loose, causing core deviation;
B. The wire deviation adjustment is carried out by adjusting the outer mold with the head locking sleeve, and the principle of less looseness and more tightness should be followed in the adjustment;
5. What is the purpose of preheating the stranded wire?
A. To increase the adhesion between the adhesive and the copper wire, in order to enhance the anti sway performance of the core wire.
6. What is the function of a spark machine? How to set up a spark generator? How to handle spark machine alarms?
A. The function of the spark machine is to detect insulation defects (such as insufficient insulation thickness or exposed copper wires) in the core wire during production
B. The spark machine should be set at 3kV during production;
C. The alarm should be immediately adjusted to resolve this defect and the defect should be scrapped;
7. What is the purpose of a filter?
A. 1. Filter unmelted adhesive or impurities; 2. Adjust the pressure of the extruder;
B. Prevent the rubber material from scorching or hardening in the screw