Laboratory small mixer small open mill

Introduction of common rubber machinery and equipment -- rubberProduction Equipment   

It is a machine for preparing rubber or semi-finished products, including raw material processing machinery, rubber mixing machine, extruder, calender, curtain canvas pretreatment device and cutting machine.

 rubber mixing machine:

 The rubber mixing machine is divided into two categories: open type and closed type.

 Open type rubber mixing machine (open mill):

 double-roller open type rubber mixing machine1826The year began to be used for production. Its structure is relatively simple, modern still commonly used. 

 It is mainly used for hot refining, tabletting, breaking, plasticizing and mixing of rubber. It is composed of roller, roller bearing, roller distance adjustment device, emergency brake device, frame, machine base, transmission device and heating and cooling system.

The working principle of the open rubber mixing machine is: raw rubber or rubber material is pulled into the roller gap by friction between two rollers rotating at different speeds, and the plasticity is increased by strong shearing and extrusion.

 Closed rubber mixing machine: (internal mixer)

 1916The invention of the oval rotor closed rubber mixing machine

Mainly used for rubber plastication and mixing. It has one more chamber than the open mill. After the raw rubber and compounding agent are loaded into the mixing chamber from the hopper, the material door is closed, the upper top bolt of the pressing device is pressed down, and the two rotors in the mixing chamber rotate in opposite directions at different or the same speed. The loaded rubber material is constantly stirred, rolled and strongly kneaded between the rotors and between the rotors and the mixing chamber, resulting in oxidative chain scission and increasing the plasticity.

At the same time, the rubber material is dispersed and evenly mixed due to shear action, so as to achieve the purpose of mixing rubber. Since one hundred years, the closed rubber mixing machine has developed rapidly in the rubber industry. Later appeared in other forms of rotor closed rubber mixing machine. The mixing cycle of the modern closed rubber mixing machine is.2.5～3Minutes, the capacity of the chamber is up650l.

 Extruder:

 Rubber machinery is used to extrude treads, inner tubes, hoses and various rubber strips, and is also used to cover cables and wire products. Screw extruders are common. Its working principle is: the rubber material is stirred, mixed, plasticized and compacted in the barrel by means of the rotation of the extrusion screw, and then moves in the direction of the head, and finally extrudes a certain shape of product from the mouth. According to the needs of the product, multiple machines can be used for compound extrusion of a variety of rubber materials. Screw extruder is divided into two kinds of hot feed and cold feed. The hot feed extruder is usually fed with a strip of material that has been preheated by an open mill. The rubber fed by the cold feed extruder is not subjected to hot refining, which can save the hot refining equipment.

Calendering:

It is mainly used for laminating, laminating and embossing of curtain canvas. The main working part of the calender is the roller, and the number of rollers is usually3or3More. When the rubber material with a certain temperature and plasticity is fed into the roller gap of the opposite rotation, it is strongly squeezed and extended under the action of friction to form the desired product. No. yi calender in1857It was made and used in production, and has since been continuously improved. especially20Century50Since the 1990 s, the development of the plastics industry has effectively promoted the improvement of high-precision and high-speed calenders. In order to obtain calendered products with uniform thickness, the new calender is generally equipped with a roller deflection compensation device. The thickness of the calendered semi-finished products is measured by special equipment, and some calenders are also equipped with an automatic thickness adjustment system controlled by an electronic computer.

Characteristics of Mixing in Internal Mixer

The plasticizing rubber and various compounding agents are put into the internal mixing chamber of the internal mixer with high temperature and high pressure. After a short time of kneading, dispersing and mixing, the mixing rubber required by the process can be obtained.
 The mixing process is:Upper top bolt lifting→Feeding→Upper top bolt falling→pressurized mixing→End of mixing→Flip→discharge→Flip back.