Advantages of phenolic resin laminated sand regeneration
Phenolic resin laminated sand has a phenolic resin film remaining on the surface of the old sand, which cannot be reused without regeneration. Phenolic resin laminated sand recycle line can regenerate the used waste sand and reuse it in an environmentally friendly way. Phenolic resin laminated sand regeneration line can reduce the production cost of phenolic resin laminated sand manufacturers by re-processing the used sand to its original state through high temperature. and through high temperature regeneration of the sand compared to the original sand impurities less, the production of higher quality cladding sand, sanzhuji according to the phenolic resin cladding sand regeneration characteristics to make the following summary:
1. Regenerated sand advantages
1.1 thermal expansion rate is reduced, reduce casting defects
Waste shell type (core) sand after casting, a part of the original sand in contact with the iron has undergone phase change, after regeneration expansion rate from 1.3% to 1.5 reduced to 0.5%. The reduction of the high temperature expansion rate of silica sand can avoid or reduce the defects of the casting such as sand eye, deformation and so on. Therefore, the use of low expansion rate of recycled sand for precision casting production, while improving the quality of the castings, but also reduce the additional materials due to reduce production costs.
1.2 gas emission reduction, reduce casting porosity
After regeneration of the sand alkaline earth metal oxides and organic matter to reduce the amount of gassing to 0.5ml/g, only one eighth of the original sand. The amount of gassing is the main cause of casting porosity, domestic general use to reduce the amount of resin added and its organic additional material, to ensure that the user strength requirements, from the past more than 30ml/g reduced to the current 16 ~ 18ml/g. Regenerated sand due to the basic removal of gassing impurities, the amount of gassing can be reduced to less than 12ml/g. The use of regenerated sand can significantly reduce the occurrence of casting porosity.
1.3 Improve bond strength hair, reduce the amount of phenolic resin
Regenerated sand its silica silicon oxygen Jian activity enhanced, so that the phenolic resin coating improved, improve the bond strength between the overcoat sand and resin, help prevent castings sticky sand. The overcoated sand produced with regenerated sand can reduce the resin dosage by 10%~15% than the original sand under the same technical index. The strength ratio of recycled sand to original sand is more than 1.12 to 1 under the same resin addition. The reduction of resin dosage in casting production can improve the production environment, improve the strength to reduce the sand core fracture, cracking of the mold surface and other phenomena.
1.4 Fluidity increase
Waste sand in the regenerative furnace for boiling roasting process of relative friction extrusion and impact to improve the roundness of the sand surface, the production of film sand fluidity also increased accordingly, the use of sand core or sand filling degree significantly improved.
2. Equipment composition and working principle
2.1 Waste sand bin
It is used for storing used and waste phenolic resin laminated sand. There is a plate feeder under the waste sand bin, through which the waste sand is sent to the next process. The plate feeder is used to ensure the quality of regeneration at a uniform speed and to screen out large stones from the waste sand to ensure the normal operation of the equipment.
2.2 Suspended Permanent Magnetic Separator
After the waste sand passes through the suspended permanent magnetic separator to the crushing screen, the suspended magnetic separator produced by sanzhuji is crossed with the sand conveying belt, showing a cross-shaped cross, and the magnetic material in the waste sand is screened out through two sections of magnetic separation to ensure the quality of the recycled sand.
2.3 Crushing Screen
The crushing screen will grind and crush the large sand blocks to waste, and the 3.7kw power motor effectively crushes the sand blocks. High-strength shock spring is not easy to break durable, bracket box welded and polished smooth, rejecting low cost and improving product quality.
2.4 Lifting machine
Bucket elevator is divided into two types of transmission: belt type and chain type.
Belt type structure: use customized 10mm high wear-resistant rubber belt. With the advantages of having a long life, more durable, etc. The belt service life is more than 5 years under the condition of continuous production all day long.
Chain type structure: Using chain drive, compared to belt type hoist, there is a higher lifting height.
Will be matched according to the equipment required, or special customized according to customer needs
2.5 Furnace front silo
After magnetic separation and crushing, the waste sand enters the furnace front bin, which is equipped with auger conveyor to convey the sand to the vertical regeneration furnace at a uniform speed.
2.6 Vertical regeneration furnace
The vertical roaster is composed of preheating system, thermal regeneration system, dust removal system and electric control system together. The output is 5~6 tons per hour, which has the advantages of gas saving and high output. Compared with the horizontal regenerator, it is more gas-saving. It consumes only 50~60 cubic meters of natural gas per ton of sand, and the gas consumption is only 50% of that of the horizontal furnace.
The waste sand to be regenerated is fed into the regenerating furnace through a screw feeder. The regeneration furnace is 10 meters high and the upper part is a preheating system with a buffer structure inside. The sand grains enter and fall from the entrance and the hot flue gas rises from below inside, so that the sand grains are preheated. The lower part is boiling roasting system, the sand is boiling and tumbling in the roasting system, and the sand is heated to the set temperature by the burner, so that the surface resin is burned away or loses its adhesion to achieve the purpose of regeneration. sanzhuji has developed another regeneration furnace with buried burning method after continuous research and test, and the sand is buried and burned in the regeneration furnace after heating, so that the regenerated sand is of better quality.
2.7 Boiling cooling bed
The cooling process boils the sand by high pressure wind, which effectively removes the excess dust of the sand and improves the strength of the regenerated sand coating. It saves 8~10% of resin than general boiling bed out of sand.
The cooling bed produced by sanzhuji has a unique heat recovery structure, which recovers the residual heat of the sand during the cooling process through the heat recovery system to reuse it and convert it into energy to return to the regeneration furnace for reuse, which can effectively reduce the regeneration cost.
2.8 Grading screen finished product bin
The grading screen screens and filters the large particles and other impurities in the recycled sand again, and enters the finished product bin for storage.
Qingdao Sanzhuji Equipment Manufacturing Co., Ltd. specializes in the production of Green Sand Molding Line,Self-hardening sand molding line,foundry machines,Sand molding machine,Sand casting equipment,sand mixer,GS high efficiency rotary mixer,Resin sand mixer,no-bake resin sand mixer,Jolt squeeze molding machine/Jolt-squeezing moulding machines,Multi- Piston Moulding Machine/Hydraulic multi-piston moulding machine,sand casting molding machine,sand reclamation equipment，foundry molding machine,flaskless moulding machine,shot blasting machine,dust collector,according to the amount of old sand recovered Carry out plan customization, and provide sand reclamation equipment installation, commissioning, and training. Welcome guests to visit the factory.
