The Laboratory Two Roll Mill (LTRM) is an electric mixing machine. It shears and compresses polymers, such as rubber, plastic, and elastomer materials, or mixtures with similar melting points, using a pair of rotating rolls preheated to the required temperature, converting raw materials into various compounds.
Two Roll Mill is a must-have machine in the plastic and rubber sectors for formula development, color matching, small batch testing, pilot production, contrast, and quality control.
Significantly, additives in the form of particles, powder, and liquid are permitted to be added to the base as activators, fillers, or oils. The interior macromolecular chains of the raw materials are broken correspondingly. This is done for mastication as the two rolls rotate, and the compositions inside the rubber compound are further dispensed to complete mixing. This generates sheet-like materials for further molding desired products.
Throughout the procedure, the operator must physically cut, fold, and roll the material on the front roll with a bamboo or wood instrument to ensure the composition’s homogeneity.
This article will explore the purpose and function of the lab two-roll mills. Read on
What is Two Roll Mill?
The Lab Two Roll Mill is an open-type rubber refining equipment. A sort of rubber roller exposed machine used in a rubber factory to produce plastic rubber, mixed-rubber, or hot refining.
The major functioning pieces are two hollow or drilling rollers revolving in opposing directions. On the operator side, the component is known as the front roller. It can vary the roll distance and adapt to the operation requirements by moving forward and backward using manual or electric movements.
Notably, the rear roll is fixed and cannot be advanced or reversed. Significantly, the two rollers are roughly the same size and rotate at different speeds.
With the rotation of the roller, the distance between the two rollers is drawn, and the raw glue or glue material is subjected to strong shear to achieve the aim of mixing. The mill is also utilized in the processing of polymers and other departments.
The History of Two Roll Mill and Development
The two-roll mill was the first to be employed in the rubber business, and it has the most basic structure of all rubber machinery.
A manual-driven single-roller trough rubber, the refining machine was invented around 1820. In 1826, a double-roller rubber mixing machine was utilized in rubber production. It also has a more than 180-year history.
In 1955, China began designing and manufacturing large-scale drilling machines. The mill’s design and manufacturing levels have substantially advanced during the last fifty years. Domestic-created new-type structure mixers have constantly been emerging in recent years and effectively promoted drilling machine development.
Until now, the domestic mill has evolved into a series. It also accomplished some standard design work and has been exported internationally.
Notably, the opening mill is being developed and updated as the rubber industry continues to develop because of the application and advancement of equipment such as the extruder. The mixer and continuous mixer’s application range has been substantially decreased in the automatic water mixing manufacturing line.
However, it is still frequently utilized in medium and small-sized companies, particularly in manufacturing recycled rubber and unusual rubber kinds in small batches and rubber materials.
Lab Two Roll Mill Working Principle
With the rotation of the rolls, the raw materials and additional components put between the two rollers are dragged into the roll gap and subjected to intense squeezing and shearing. Material deformation increases the contact area between the compositions.
When the stress applied to the materials exceeds the allowed limit, the interior macromolecular chains of the materials are stretched and broken, causing the compositions to be further spread and mixed uniformly. This process is repeated until the desired compound is obtained in a sheet shape and the expected mastication or mixing state is reached.
What Is the Structure and Classification of Two Roll Mill?
The two-roll mill’s essential components are the roller, bearing, frame, gland, driving device, distance adjusting device, lubrication system, temperature adjusting device, and emergency braking device. Although the mill is varied in size, its basic structure is the same. The mill primarily relies on two relatively rotating rollers to crush and shear the rubber throughout the refining process. The chain of huge molecules inside the rubber is broken after several repetitions of kneading and the chemical action accompanying the kneading process. Diverse components inside the rubber are mixed uniformly, and eventually, the objective of rubber refining is fulfilled.
Because of the difference in surface speed and temperature of the two rollers, the film excluded in the roller gap is coated on one roller. It returns to the other two rollers, completing the rubber refining process twice. Rubber molecular chains change from long to short during plasticization.
The elasticity changes from large to small; during the mixing process, the surface of each adhesive component is constantly updated and blended equally. After passing the rubber material through the distance multiple times in the batch operation of the mixer, eventually chop the lower pieces.
Significantly, the rubber material causes the extrusion effect as the roller spacing gradually lowers, resulting in a rise in transverse pressure and extrusion. The stronger the shear force, the greater the pressure; the speed ratio between the front and back rollers causes shear action.
Notably, the machine’s technical specifications must include roller speed, speed ratio, power, mixing capacity, roller distance adjustment range, external installation size, and transmission mode.
Two Roll Mill Applications
Two-roll mills are widely used in the mixing of foods, sealants, adhesives, coatings, pigments, dental composites, glass coatings, chemicals, pharmaceuticals, paints, graphite/carbon, plastisols, cosmetics, high-performance ceramics, electronic thick film inks, and mix printing inks. They are also utilized to make artificial polymers, soap, electronics, and cable covers, thanks to recent technological advancements.
Small bench models are used for low-volume production, laboratory work, and bench-top development work. The larger bench and floor variants are developed to meet the diverse needs of pilot plants from low-volume production to high-volume manufacturing.
This process has many advantages, the most notable of which is that it allows high-viscosity pastes to be milled, as well as the advantage that, due to their high surface contact with the cooled rollers, the temperature is allowed to remain low regardless of how much dispersion work is put in. The main downside is that the paste’s vast exposed surface on the rollers causes volatile loss.
In conclusion, two roll mills are essential tools for a wide range of industries, offering unbeatable performance and producing high-quality products that thoroughly enhance the industries. And when it comes to finding the best equipment for your needs, two roll mills are designed to deliver precision, consistency, and efficiency, helping you achieve your goals and take your business to new heights.
With our cutting-edge technology and expert support, you can trust a reliable vendor to provide the necessary equipment to succeed.