Introduction of vacuum casting technology and vacuum resin casting equipment

---

Vacuum casting technology Introduction

Vacuum casting technology refers to the development of epoxy resin casting from atmospheric molding to vacuum molding. Vacuum casting molding makes it easier to discharge the bubbles in the castable, and the internal quality and appearance quality of the products are greatly improved, which promotes the development of power transmission and transformation technology. However, the focus of users in this period is mainly the internal performance. And not too concerned about the appearance quality.

Epoxy resin casting technology is a new type of insulating material manufacturing technology produced in the 1950s, which emerged with the development of power transmission and transformation technology. In the early days, the voltage level of power transmission and transformation equipment was low, and its core insulation components were still made of traditional insulating materials. When the voltage level of power transmission and transformation equipment increased, the shortcomings of traditional insulation materials became prominent, especially those that could not meet the power frequency withstand voltage and local In order to solve these problems, epoxy resin casting technology came into being as required for discharge.

Vacuum casting technology appeared in the 1960s, and epoxy resin casting developed from atmospheric molding to vacuum molding. Vacuum casting molding makes it easier to discharge the bubbles in the castable, and the internal quality and appearance quality of the products are greatly improved, which promotes the development of power transmission and transformation technology. However, the focus of users in this period is mainly the internal performance. And not too concerned about the appearance quality.

In the late 1970s, my country began to introduce a complete set of vacuum systems controlled by microcomputers. Vacuum technology was realized from material pretreatment, piping system to mixed pouring system, and the degree of automation increased, and the quality of pouring products rose to a new level. Today, the material system and formula are very mature, the pouring equipment has been intelligent, and the product performance can fully meet the requirements of high-voltage power transmission and transformation equipment. At present, the epoxy casting for the megavolt transmission and transformation equipment of the highest voltage level Parts have been made domestically. At this time, the appearance quality has become the focus of user acceptance and manufacturers’ attention, and it is also the basis for epoxy casting products to gain a foothold in the market.

Introduction of pouring process
Pouring process: material pretreatment (the insert is coated with adhesive or semi-conductive rubber, the filler is evacuated and dried, the solid epoxy resin is melted and vacuumed, and the curing agent is vacuumed) → material mixing (first mix the filler and epoxy resin at once Vacuum, then mix with curing agent) → pre-curing (casting material is cured in a curing oven, and the curing degree is above 80%) → demolding and mold loading (keep the proper temperature to unload the product and quickly load it into the next mold) →Post curing (concentrated curing of the product after demolding to improve the degree of curing and release internal stress) →Post treatment (clean up the product gate, mold clamping seams and other defects) → inspect the packaging.
Compared with traditional insulating materials, epoxy vacuum casting products have many unique advantages:
①No air gap or less air gap, the product has excellent electrical insulation performance;
②Pouring molding has good fluidity, filling the cavity naturally, and good product uniformity;
③Due to the good electrical performance, the product can be miniaturized and the host structure optimized;
④The product can be made into complex shapes, and it can be formed at one time, and the integrity of the metal insert and the insulating material is good;
⑤Good weather resistance, can be used in indoor and outdoor fields;
⑥The product is solid, non-flammable, safe and convenient to use.
However, the process also has shortcomings:
① There is no reinforcing material in the system, the mechanical properties are poor, and the main engine is broken during use;
② A certain stress is generated in the product, and the product may crack when the stress is accumulated and released;
③There are various defects in appearance quality

The advantages of SIMUWU’s epoxy resin vacuum casting equipment
Epoxy resin vacuum casting equipment is developed by our company on the basis of drawing lessons from imported equipment and combining the performance characteristics of imported and domestic raw materials. The technical level is in a position. Epoxy resin vacuum casting equipment is used for vacuum casting of dry-type transformers, reactors, high voltage switch insulators of transformers and other products.
1. Epoxy resin vacuum casting equipment can realize intermittent and periodic production with high production efficiency.
2. Membrane degassing technology, faster, more effective and fuller dehydration and degassing of the mixture, the preparation system can realize full vacuum processing.
3. The special mixing system can more fully mix the filler with epoxy resin during the filling process to prevent the filling from forming into small clusters or uneven mixing, which will affect the casting quality. The special structure device avoids the precipitation of the bottom filler.

Learn More : Vacuum Casting Plant