Craftsmanship | Unique Advantages of Liujing Technology Group

1、Overview

The production process used in this project is independently developed by Willow Crystal Technology. Willow Crystal Technology has a group of industry experts, scientific research colleges and universities led by doctors and masters of scientific research team and modern research and development centre, with a number of technical patents and achievements. In order to help the foundry industry towards green and promote the recycling of foundry waste sand, the company's R & D centre researchers have learned from all the strengths and weaknesses of various domestic and foreign waste sand treatment devices, the use of technologically advanced and less energy-consuming production process, combined with advanced and reasonable, energy-efficient structural design, the independent research and development of successful foundry waste sand regeneration technology and equipment.

In 2019, Liujing Technology introduced the German RS inorganic binder waste sand regeneration equipment, becoming a domestic enterprise with both organic and inorganic waste sand regeneration capacity, solving the problems of high energy consumption for regeneration of similar production equipment at home and abroad, unstable quality of regenerated sand, low recycling rate of finished products, and high comprehensive cost, which is in the absolute leading position in the industry.

(Products: Coated sand)

(Product: sand core)

2、Regeneration mechanism

1）Regeneration mechanism of casting waste sand by thermal method

The low temperature roasting regeneration of casting waste sand can achieve the effect of high quality and low energy consumption mainly by using the principle of secondary roasting. The mechanism of secondary roasting is as follows:

The heat exchanger is used to increase the temperature of the air entering the furnace, so that the residual carbon in the waste sand can be burned more efficiently in the high-temperature heated air, and the resulting combustion heat is also used as the heat source for roasting. The hot sand continues to flow in the heat exchanger for a long time, the unroasted charcoal residue in the waste sand continues to be burned, and the heat of combustion is absorbed by the heat exchanger, thus saving energy again. The residual charcoal in the waste sand is burnt out in the second roasting, thus realising complete regeneration.

(2) Willow Crystal's Thermal Regeneration Process

The regeneration sand production line equipment and process independently developed by Liu Jing Technology is a multi-functional and multi-purpose production line that adopts thermal and mechanical regeneration to regenerate the resin sand waste sand or clay sand waste sand after casting, and then use it as the original sand of coating sand or clay sand.

(Equipment: independent innovation based on the integration of domestic and foreign advanced regeneration technologies)

(Equipments: Introducing German Rs inorganic regeneration equipment in 2019)

3、Introduction of technical characteristics of production process

(1) Roaster system: The low-temperature roaster of Liu Jing Technology has many times of roasting, and the organic matter or surface film on the surface of waste sand is fully burnt, so the quality of regenerated sand can be fully guaranteed, and the energy consumption is also greatly reduced. The new energy-saving roaster device independently researched and designed by Liu Jing Technology is a kind of intermittent roaster with simple structure, reliable use, low roasting temperature and low energy consumption. The main features are:

(1) Intermittent combustion, low roasting temperature, greatly reducing the damage to the furnace chamber and core, etc., so that the life of the furnace is greatly improved, almost no maintenance;

(2) Use of waste sand residual carbon in the combustion process of the heat generation mechanism, to achieve multiple roasting, to achieve complete removal of carbon film, regeneration purposes, to obtain high-quality recycled sand;

(3) Realise the heat exchange between air and roasted sand, increase the air temperature, and greatly reduce energy consumption;

(2) Automatic sand discharging device: when discharging, the computer automatically controls the discharging valve to achieve intermittent cyclic discharging. This device is not affected by high temperature, not easy to mechanical deformation, stable and reliable, long service life, compact structure, easy to operate.

(3) The heat preservation system of the roaster: the design of the furnace lining adopts advanced refractory materials and heat preservation and insulation technology, which not only saves energy, but also reduces the temperature of the exterior of the furnace body greatly, and the temperature of the exterior of the furnace body is only about 50 degrees.

(4) sand level automatic control system: the sand level in the roaster is crucial to the quality of the product, sand level is too high or too low directly affect the quality of recycled sand roasting. When the sand level in the furnace is set at a low level, it will automatically shut off the fire, and when the sand level in the furnace is set at a high level, it will stop feeding.

(5) Cooling of high-temperature sand: The sand cooling system has the functions of sand cooling and dust removal. The hot sand contacts with the heat exchange parts in the suspended state and carries out heat exchange and cooling, and in the process of movement, the sand particles rub together to make the adhering micro-powder detach and enter into the dust removal system along with the airflow.

(6) Surface treatment: the surface treatment device consists of scrubbing, grinding, cutting, shaping and other multi-stage surface treatment devices overlap and combine, low force cutting machine can achieve continuous force cutting, the sand surface 0.01mm alkaline material removed and sand surface dust separation, greatly improving the quality of regenerated sand. The surface treatment device has simple structure and long service life.

(7) Classifier: The regenerated sand with different granularity will be classified with multi-stage granularity according to the needs of production.

8）Automatic control system: Liu Jing Technology recycled sand production line adopts self-developed automatic control system with independent intellectual property rights. The system consists of a general control cabinet and some on-site control keys. It has the following functions:

(1) The whole control system is equipped with manual and automatic control functions;

(2) Each temperature, pressure, material level and other control points are equipped with temperature and pressure monitoring and control instruments and meters;

(3) There are sound and light alarms for motor overload and temperature overrun, and automatic shutdown;

(4) Conveying, lifting, feeding and other equipment and furnace working conditions with the heating system interlock, if the conditions do not have continuous production or abnormal shutdown, the entire production line will automatically alarm, the heater stops heating;

(5) The use of multi-point, combustion status, pressure automatic monitoring, in order to safety in the programme designed to have enough time after the furnace stops on the discharge of combustible gases.

Willow Crystal's regeneration sand production line can handle resin sand, clay sand, cold core, hot core of all kinds of casting waste sand, can be long-term, safe and reliable operation, the regeneration of Willow Crystal's regeneration processing system after the treatment of waste sand reaches the standard of replacing the new sand can be used to replace the new sand for the cold core, hot core, etc., to ensure that the regeneration of the silica sand quality, performance and production requirements; and the production line of energy consumption is much lower than the same kind of equipment at home and abroad, the actual natural gas consumption of foreign products 200,000 large. The energy consumption of the production line is much lower than that of similar equipments at home and abroad, the actual consumption of natural gas of foreign products is 200,000 kcal/t sand, the actual consumption of natural gas of Liujing Technology series products is 50,000-100,000 kcal/t sand, meanwhile, the production line of Liujing Technology has the features of no running parts of the key equipments, the long service life of the roasting furnace (almost no maintenance), and the realisation of the high-temperature logistics continuous flow control with no gaps.