Equipment Introduction
The SLG85-A large twin-screw extruder is a puffed food equipment developed using advanced twin-screw extrusion technology from abroad, combined with our company's rich experience in puffed food technology research over the years, which is suitable for China's national conditions.
The device adopts a stable and reliable variable frequency speed regulation system, an accurate pressure sensing system, and more convenient and accurate operation. The spiral part adopts a specially designed screw structure with two co rotating screws, double ended circular arc grooves, and kneading blocks. It has the characteristics of self-cleaning function, high push efficiency, and good shear homogenization effect. This equipment has high output, reasonable design, high degree of automation, easy operation, small footprint, energy saving, and low processing loss. It can be deeply redeveloped and applied to grains. This extrusion equipment belongs to the advanced level in China, and its development and production have filled the gap of large diameter twin-screw in ChinaPuffing equipmentThe blank space has been identified and recommended by the China Packaging Food Machinery Association of the Ministry of Machinery and Electronics as a high-quality domestic food machinery.
　　Equipment structure:

1. Vacuum suction machine 2. Storage drum 3. Feeding device 4. Mixing device 5. Forced feeding 6. Drive device 7. Distribution box 8. Squeezing chamber 9. Rotary cutting device 10. Lubrication device 11. Oil cooling device 12. Control cabinet 13. Platform

As shown in the figure, the SLG85-A host is mainly composed of 11 parts. Firstly, the raw materials are mixed and added to the storage drum through a vacuum automatic feeding machine. Then, they are evenly fed into the mixing device through a feeding device. The mixing device disperses the raw materials evenly and automatically moves them to the discharge port of the drum. After forced feeding, the mixed raw materials are transported to the extrusion chamber. There are heating and cooling devices outside the extrusion device to control the constant temperature required for the raw materials. The screw in the extrusion device is controlled by a powerful driving device and a reliable distribution box to ensure the stability of the equipment. The distribution box is a key part of the equipment, which is forcibly lubricated by a lubrication device and an oil cooling device to ensure operation! The raw materials are mixed, kneaded, and extruded into semi-finished products through specific molds under high temperature and high pressure in the extrusion chamber, and finally cut into qualified products by a rotary cutting device.
All power of this equipment is centrally controlled by the control cabinet; The conditioner and storage device are installed on the workbench, making the equipment structure compact and easy to operate!

In addition to the 13 major parts shown in Figure I, the SLG85-A host also requires a cooling water tower and a quantitative water injection machine to ensure its normal operation. The specific arrangement and connection are shown in the figure!
　　Equipment Principle
The main components of a twin-screw extrusion system are the screw and the screw sleeve. Both screws are double headed right-handed, meshing with each other and rotating in the same direction. During the working process, the materials adhered to the screw are scraped and pushed forward. The screw is composed of 20 shear rings and kneading blocks with pitches of 80mm, 60mm, 40mm, and 80mm respectively. All threads are trapezoidal with a depth of 15mm. The material increases the contact area with the sleeve, making it easier to absorb and heat externally, which is beneficial for the maturation of the material; On the other hand, when using the last specially designed 20 shear rings, the material can be fully subjected to shear forces, increasing internal energy and completing material organization. The screw is connected by a spline shaft sleeve, forming a concentric screw as a whole. This connection method has good interchangeability, easy assembly and disassembly, and is easy to replace.
The lubrication system consists of a gear pump, an oil tank, and an oil circuit, and is equipped with a dedicated oil cooling device to forcibly lubricate and cool the rotating parts of the distribution box.
The main driving force in the transmission system is a specially customized FA series parallel axis helical gear reducer, directly connected to a 90KW motor. The power enters the distribution box and is decomposed into two output shafts that rotate in the same direction; The helical gears Z30 and Z60 are external meshing and belong to a triangular transmission system. The two Z30 helical gears each carry the torque and radial thrust transmitted by the screw. The speed control system of this machine adopts variable frequency speed control technology, which is reliable in adjustment, has a large adjustment range, and runs smoothly. The gear shafts inside the box are equipped with the most advanced series thrust cylindrical roller bearings to ensure the stability of the equipment.

The heating system and the cooling system of the machine barrel complement each other (matched with the water tower). As shown in the figure, this host consists of six machine barrels, including one feeding section machine barrel, one cooling section machine barrel, and the other four cooling water tanks as shown in the figure. The water tank is equipped with copper pipes to cool the machine barrel, and there is one infrared stainless steel heating ring for each area outside to control. The power of each heating ring is 6KW, for a total of 24KW. The temperature in each area can be independently adjusted. Cooling is divided into five zones, four of which correspond to heating, and are automatically controlled by solenoid valves according to the heating temperature for entry and exit. The last zone has a cooling water bag as a continuous water supply at the machine barrel closest to the feeding port!
　　Technical Specifications
Total power of equipment: 121.12KW
Screw diameter: f85mm
Screw length: 1960mm
Length to diameter ratio: 1:21
Screw speed: 0-406rpmz
Processing capacity: 500-800kg/h
Temperature control range: 0-399 ℃
Main driving power: 90KW
Heating power: 6 × 4KW
Speed regulation method: Variable frequency speed regulation
Rotary cutting drive power: 2.2KW
Oil pump drive power: 0.37KW
Water tower driving power: 0.55KW
Oil cooling power: 0.18KW
Cooling fan power of water tower: 0.12KW
Dimensions of water tower: 900 × 900 × 1850 (mm)
Machine center height: 1200mm
Workbench height: 2400mm
Overall dimensions of extrusion host: 5200 × 2700 × 5500 (mm)