What Is Slitting? Breaking Down the Process in Manufacturing

Introduction

Do you ever think about how a large roll of material such as steel, paper, aluminum, foil or nonwoven material is cut into thin and equal strips? In the packaging, textiles, or any other converting industries, the process of slitting is very important in making this possible. But what is slitting, in fact, and why is it so important in the sphere of manufacturing?

Slitting may sound like a very easy process but in actual practice it is a very delicate process that needs the right tools and technique to be done properly. The capacity to take a large coil of material and slit it down to a narrower width that is usable is a critical factor in industries that require precision and accuracy. In this article, we will discuss what slitting is, why it is used in today’s manufacturing industry, and how you can select the most suitable slitting technique. Whether you are using plastic film, paper, aluminum or soft material such as foil, slitting is the first thing that you need to know to improve your production line and give your customers the best products.

What is Slitting? How it Works?

So, what is slitting? In its simplest definition, slitting is a process of cutting a large roll of material into a smaller width or smaller coils of material to meet certain requirements in the next process. It entails feeding the roll of material through a slitting line where it is cut with accuracy by rotary knives or razor blades. The narrower strips are then wound into coils and are ready for the next process of production or for immediate use in different industries.

Why Is Slitting Essential in Manufacturing?

Slitting is a very important process in manufacturing since it is a process that helps in cutting the material into the right size and shape at the initial stage of production. In this way, slitting reduces wastage of raw materials by cutting them into narrow strips or coils that are suitable for various industries and increases flexibility in the design and use of the final product.

For instance, a standard roll of aluminum foil can weigh up to 1000kg and be 1.2 meters wide. However, there are other packaging or food industries that may require much narrower widths, which range from 100mm to 500mm. If slitting is not done, it becomes very hard for the manufacturers to produce these widths in the best way possible, which would result to wastage of raw materials or otherwise, inefficient use of the same. The slitting process can be optimized to save 5-10% of the material, which is very important when working with expensive materials such as aluminum foil, which costs up to $2 per kg.

Also, the use of automated slitting machines increases accuracy and dependability, decreases wastage, and increases productivity. The implementation of slitting in the production line can help manufacturers to make the best use of resources, reduce costs, and improve competitiveness in the market. Hence, slitting is a critical factor in enhancing efficiency in the manufacturing industry.

Main Types of Slitting Processes

Razor Slitting

Razor slitting is one of the most common cutting techniques that are preferred for cutting soft materials and thin substrates. This method employs the use of razor blades to make neat and clean cuts which is very important in industries where the material cannot be compromised in any way such as in the manufacturing of foils, plastics, papers, and thin fabrics. For instance, when cutting aluminum foil, razor slitting can achieve slit width of 2 millimeters, which is very thin and precise compared to other cutting methods.

The process involves pulling the material through a set of rotary knives and the razor blade cuts the material as it passes through. This leads to thin and neat strips of material that are fit for packing or other subsequent processes. Razor slitting is especially appreciated for its precision and ability to make very thin and clean cuts, which are important for the further use of the material.

Shear Slitting

Shear slitting, as the name suggests, which involves the use of two blades, the upper blade and the lower blade that work in a shearing manner to cut the material. The blades exert pressure on the material to be cut and this leads to the material being cut along the cutting line in a clean manner. This method is suitable for thicker and stiffer materials like metals, nonwoven fabrics or thicker plastic films. Unlike razor slitting, which is more effective for thin materials, shear slitting applies more force and is therefore better suited for heavier industrial rolls and materials.

One of the advantages of shear slitting is that it is a very flexible process. It is versatile and can work on a variety of materials with a lot of accuracy. For instance, in the packaging sector, shear slitting is applied to cut thicker cardboard or corrugated paper into the right width for packaging to fit the required dimensions without compromising on the strength or the durability of the packaging material. Shear slitting is suitable for large scale cutting since it provides accurate slit width and high quality cuts regardless of whether the material is a high strength material such as cardboard or a flexible material such as plastic film.

Crush Slitting

Crush slitting differs from razor and shear slitting by the fact that it features the use of tools or rollers that have been specifically designed to apply pressure to an object in order to create indentations along a specific line. The process involves weakening the material at the dearly prepared indentation or line while the indent is not fully cut through. The action of crushing is particularly useful for softer materials for instance thin plastic films, paper or cardboard since those materials are easily compressed to create perforations with the additional benefit of enabling high speed processing without the need for precision cuts.

While not as precise as razor or shear slitting, crush slitting excels in high-volume production. It is suitable for applications where the precision of the cut is not very important. For example, in the packaging industry where large rolls of material have to be converted into narrower strips. While the edges are not perfectly smooth, the process is very efficient and inexpensive, which makes it ideal for applications where high volume is more important than accuracy.

Slitting Process	Key Features	Applicable Materials	Precision	Production Speed	Applicable Scenarios
Razor Slitting	Smooth cutting, narrow widths, high precision, suitable for delicate materials	Plastic films (BOPP, PET, PE, PVC), Aluminum foil, paper, soft textiles	High precision (±0.1 mm)	Medium speed	Food packaging, pharmaceutical packaging, electronic films
Shear Slitting	Powerful cutting, wide applicability, clean edges	Metal coils (aluminum, steel, stainless steel), Nonwoven fabrics, thick plastic films, cardboard, rubber materials	Medium precision (±0.5 mm)	Medium speed	Metal processing, automotive manufacturing, construction industry
Crush Slitting	High-speed production, cost-effective, creates perforations	Thin plastic films, paper, corrugated cardboard, low-density foam, soft packaging materials	Low precision (±1 mm)	High-speed production	Quick packaging, carton production, low-cost material slitting

Key Considerations in Choosing a Slitting Method

In choosing the right slitting method, there are some important factors that should be taken into consideration in order to achieve the best results and at the same time, minimize costs.

Material Type is one of the most important considerations. For example, slitting thicker materials like rubber or plastic sheets requires more robust equipment and often calls for shear slitting, which can handle the increased force needed for precision cuts. On the other hand, softer materials like plastic films or foil, which are thinner, may be better suited for razor slitting, where precision is crucial but less force is required.

An important aspect that needs to be considered is Cutting Precision. Razor slitting is the most suitable for the material that needs to be slit with high accuracy since it offers a high level of accuracy with tolerances of tight to ± 0.1mm. Shear slitting may not be as accurate as razor slitting, but it is suitable for thicker materials where the emphasis is on strength rather than thinness of the slit.

Another factor is the speed of production, which is important for large-scale production. Crush slitting may be the best option for applications where speed is of essence, for instance in packaging. It permits high-speed cutting, even with less precision, which makes it ideal for applications such as cutting of cardboard or plastic film where speed is of essence.

Product Use is also another factor that determines the right method to be used in a given project. For instance, if the final product is to be employed in areas that demand strength and sturdiness, for example, automotive or construction industries, shear slitting may be adopted due to its effectiveness in cutting. On the other hand, if the material is to be used for packaging where appearance and flexibility are of paramount importance, razor slitting may be more suitable due to its accuracy and smooth edges.

Other considerations include the Material Cost and the Production Volume. In large scale and low cost applications, manufacturers often use techniques such as crush slitting since they offer both speed and reasonable quality. On the other hand, if the material is more expensive or if the production is in small quantities, then razor or shear slitting may be more appropriate.

These factors have to be considered in order to choose the most appropriate slitting method that will provide the best results in terms of quality, productivity and cost.

Enhancing Manufacturing with KETE Slitting Solutions

KETE is one of the most professional slitting machine manufacturers in China, providing high precision and competitive price slitting solutions for the development of manufacturing industry. Our slitting machines are of high quality and highly reliable and come with the latest technology to enable the cutting of large rolls of material into narrower rolls, suitable for materials such as plastic films, papers, aluminum foils, and non-woven fabrics. Every machine goes through a rigorous final check before it is shipped from the factory to guarantee that it will function optimally in the harshest environment.

KETE machines are used in more than 80 countries and the annual sales is more than 2000 units. Each machine is warranted for one year so that your manufacturing line is not interrupted. We know that the proper equipment is essential for the effective functioning of your business. KETE’s slitting solutions will help you to minimize wastage and guarantee that each roll or strip is cut to the right dimensions for your intended uses. Choose KETE for high-quality slitting machines and exceptional service.

Conclusion

In conclusion, slitting is a critical process in manufacturing that helps industries to reduce the width of the material in large rolls to a more manageable size that meets production requirements. When it comes to slitting, there are three primary techniques: crush slitting, razor slitting, and shear slitting, and it is crucial to choose the right one to get the right level of precision, use the least amount of material, and work as efficiently as possible.

With the advancement of industries and the need for accuracy, slitting will remain a crucial factor in the enhancement of production lines in the world. It is possible to overcome these challenges and sustain high quality production with the help of proper tools and methods in manufacturing companies, and stay competitive in the marketplace.

FAQ

Q1: What are the factors that should be taken into consideration during slitting?

It is important to maintain alignment and stability of the material during the slitting process. Some of the factors that affect the quality of the cuts include equipment maintenance, sharpness of the blades, and the speed of cutting. High speed may lead to material distortion or low accuracy of the results.

Q2: What is the difference between slitting and other processing techniques?

Slitting is a process of cutting the material by applying force while other processes like stamping or extrusion may involve bending of the material. Slitting is more direct and flexible particularly when it comes to dimensions and shapes of the slitted material.

Q3: What is precision slitting?

Precision slitting is a process of cutting the material with a high level of accuracy, sometimes up to the level of micrometers. It is suitable for use in areas where high precision and accuracy of cuts is required, such as in the manufacturing of electronics and high end packaging materials.