月: 2022年12月

What Is an Ultracentrifuge?

An ultracentrifuge is a specialized centrifuge designed to achieve extremely high centrifugal forces, often exceeding 100,000 g, with some models capable of reaching up to 1,000,000 g. These devices are essential in separating components of mixtures based on their density, with applications spanning across research and industrial sectors. Ultracentrifuges come in two primary types: analytical and preparative, with significant cost variations reflecting their advanced capabilities and technical specifications.

Applications of Ultracentrifuges

Ultracentrifuges are utilized for diverse purposes, tailored to the specific needs of analytical or preparative tasks. Their applications include:

• Protein Analysis: Analytical ultracentrifuges play a crucial role in studying protein properties, interactions, and structures, aiding in fields like biochemistry and molecular biology.
• Cellular and Viral Component Separation: Preparative ultracentrifuges are instrumental in isolating cell organelles and viruses, facilitating studies in cell biology and virology.

Operating Principles of Ultracentrifuges

Key to ultracentrifugation is the rotor design, which influences separation efficiency and application suitability. Common rotor types include:

• Swinging Rotors: Ideal for achieving even sediment deposition and facilitating supernatant removal.
• Fixed Angle Rotors: Optimizes sediment collection at an angle, suitable for collecting dense particles.
• Zonal Rotors: Utilized for density gradient centrifugation, enabling separation of large volumes under continuous flow conditions.

Preparation and balance of samples are critical, with rigorous checks required to prevent equipment damage and ensure safety.

Features of Ultracentrifuges

Ultracentrifuges distinguish themselves by their ability to generate significantly higher centrifugal forces than standard centrifuges, offering:

• Enhanced Separation Capabilities: They can separate components with minimal differences in density, which are indiscernible in conventional centrifuges.
• Real-Time Analytical Insights: Analytical ultracentrifuges allow for the direct observation of sedimentation, providing valuable data on molecular behavior and properties.

Considerations for Using Ultracentrifuges

Operating ultracentrifuges requires adherence to strict safety protocols to avoid accidents and equipment damage. Essential precautions include ensuring sample balance, maintaining vacuum conditions to control frictional heat, and verifying chamber integrity. These measures are crucial for the safe and effective use of ultracentrifuges in high-speed separations.

What Is Cemented Carbide?

Cemented carbide is a generic term for composite alloys made by adding iron-based metals to metals in groups 4-6 of the periodic table.

In particular, WC-Co alloys, in which cobalt is bonded to tungsten carbide, are commonly used. They are extremely hard and can maintain their room temperature hardness even at high temperatures. They are also strong and resistant to external forces, such as bending.

Uses of Cemented Carbide

Cemented carbides are used in fields where wear resistance is required. Specifically, they are used in cutting and polishing tools for glass, plastic, and metal processing. They are also suitable for applications such as drills for drilling holes in rock and concrete, nozzles for industrial products, pipes for electrodes, pins for dot printers, and punch pins.

Cemented carbide is second only to diamond in hardness and maintains its hardness even at high temperatures. It is also characterized by its high strength and resistance to bending under load. They are used in fields where these characteristics can be utilized.

Principle of Cemented Carbide

Cemented carbides are composite alloys made by bonding (sintering) metal oxides of metals belonging to groups 4 to 6 of the periodic table with iron-based metals, as described above.

The following nine metals belonging to groups 4-6 of the periodic table are listed.

• W (Tungsten)
• Cr (Chromium)
• Mo (Molybdenum)
• Ti (Titanium)
• Zr (Zirconium)
• Hf (Hafnium)
• V (Vanadium)
• Nb (Niobium)
• Ta (Tantalum)

Typical ferrous metals are as follows:

• Fe (Iron)
• Co (Cobalt)
• Ni (Nickel)

Among these, WC-Co alloys made by adding cobalt as a binder to tungsten carbide are the most representative.

Cemented Carbide Manufacturing Methods

Cemented carbides are manufactured by a special method called powder metallurgy. This is because the melting point of tungsten carbide, the main material used in cemented carbide, is as high as 2,900℃, making it difficult to melt it like iron.

Powder metallurgy is a manufacturing method in which metal powder is pressed and then hardened. Cemented carbide is manufactured by mixing tungsten carbide metal powder with cobalt or other metal powder as a binder, pressing and hardening the mixture, and then sintering it at a high temperature of 1,300 to 1,500℃.

Various composite alloys can be produced by changing the composition of the metal powder to suit the application. At present, in addition to the “WC-Co series,” there are many other types developed, including the “WC-TiC-Co series,” “WC-TaC-Co series,” and “WC-TiC-TaC-Co series.

Cemented Carbide Machining Methods

Cemented carbides are so hard that they cannot be machined by ordinary methods. Therefore, it is machined either by using diamonds, which are harder than cemented carbide, or by using pulsed electric discharge from a pulsed power source.

1. Machining Using Diamond

Diamond is very expensive, so diamond abrasives are used on a wheel for cutting and polishing. The disadvantage is that the diamond portion to be cut is small, so the cutting is done gradually and the process takes a long time. For this reason, tools with a diamond coating on the cutting tool itself have recently been developed.

2. Electric Discharge Machining

Electrical discharge machining includes wire machining and profile drilling. In wire processing, wires are stretched above and below the material, and the material is cut by an electric discharge from the wires. Shape drilling refers to a method in which the material is placed in a liquid and the electrode is brought close to the material while discharging electricity to melt the metal.

Other Information on Cemented Carbide

Cemented Carbide Standards

Cemented carbide is described as HW-P20, which is a cross between a classification by cutting tool material (HW part) and a classification by work material (P20 part).

This indicates what kind of material and what kind of workpiece can be machined. Cemented carbides mainly composed of tungsten carbides are classified into HW and HF according to the particle size, with HW being those with an average particle size of 1 μm or larger and HF being those with an average particle size of less than 1 μm.

HT and HC are also listed as cemented carbides in the standard. HT refers to cermet, which is mainly made of titanium, tantalum, and niobium carbides and nitrides with a low content of tungsten carbide. HC is a symbol for coated cemented carbide, nitride, oxide, or diamond coated on one or more layers on the surface of cemented carbide.

What Is an Infrared Spectrophotometer?

Figure 1. Infrared spectrophotometer and IR spectrum image

An infrared spectrophotometer is an analytical instrument that irradiates a sample with infrared light and detects the transmitted and reflected infrared light.

It is used to obtain information about the molecular structure of a sample. The primary components of the device include a light source, spectrometer, sample, and detector. When a molecule is irradiated with infrared light, absorption occurs due to the vibration and rotation of the molecules in the sample. Since this absorption spectrum differs depending on the molecular structure, it is possible to obtain information about the molecular structure.

It is especially used to identify functional groups in molecular structures and for qualitative and quantitative analysis of samples. This method is non-destructive and easy to use and can be applied to a variety of materials, including powder samples and thin films.

Uses of Infrared Spectrophotometers

Infrared spectrophotometers (IR) are used in a wide range of fields, including pharmaceuticals, agriculture, biology, gas analysis, and forensics, where organic compounds are handled. The technique is used for qualitative and quantitative analysis of substances.

One of its main applications is the partial structure determination of compounds. This is based on the fact that each functional group has a unique absorption, and each peak is detected in a nearly constant wave number range (characteristic absorption band).

Since IR spectra are unique to a substance, they can also be used to identify unknown samples by comparing the measured spectrum with that of a standard sample. Infrared spectrophotometers, which can locally irradiate infrared light, can be used to measure minute amounts of samples and identify foreign substances in materials.

Principle of Infrared Spectrophotometers

Figure 2. Examples of molecular vibrations observed by infrared absorption

The technique used in infrared spectrophotometers is called infrared spectroscopy (IR). When a substance is irradiated with infrared light (2500-25000 nm), absorption occurs based on the vibration and rotation of molecules.

At this time, the bonds connecting atoms in a molecule show different stretching and contraction depending on the type of bond, and as a result, the absorption spectrum also differs depending on the type of bond. This is the reason why IR is suitable for structure determination of functional groups. The type of functional group can be determined by examining the wave number of the absorbed IR radiation.

The detector measures the degree to which the IR radiation is reduced from the irradiated IR radiation by absorption (or reflection) by the sample. The resulting IR spectrum (infrared absorption spectrum) has the wave number of the irradiated infrared light (unit: cm-1, read: Kaiser) on the horizontal axis and the transmittance %T on the vertical axis.

Types of Infrared Spectrophotometers

Figure 3. Schematic of dispersive IR (top) and FT-IR (bottom)

There are two types of infrared spectrophotometers: dispersive type and Fourier transform type (Fourier transform Infrared spectrophotometer FT-IR).

1. Dispersive Type

In the dispersive type, a diffraction grating is used in the spectrometer to disperse the light after it has passed through the sample, and each wavelength is detected by the detector sequentially.

2. Fourier Transform Type (FT-IR)

In the Fourier transform type, an interferometer is used to create interference waves, which are then irradiated onto the sample. After simultaneously detecting all wavelengths in a non-dispersive manner, the Fourier transform is performed on a computer to calculate each wavelength component.

It is possible to measure at all wavelengths at once, making measurements quick and easy. Because of its superior sensitivity and resolution, the Fourier transform type is currently the mainstream infrared spectroscopy method.

The advantages of the Fourier transform type (FT-IR) over the dispersive type include the following four points:

Simultaneous Detection of Multiple Wavelengths
In the Fourier transform type, IR spectra are obtained by moving a moving mirror. It is not necessary to move the diffraction grating to scan multiple wavelengths, as is the case with the dispersive type and thus enables high-speed measurement.

FT-IR is far more time-efficient when there are many objects to be measured or when noise is to be reduced by using a large integration time. In addition, since multiple wavelengths can be measured at the same time, there is an advantage in that there is less temporal variation in each wavelength (reduction of temperature drift of the measurement device).

Improvement of SNR
While dispersive IR uses a slit, FT-IR does not use a slit, and the energy reaching the detector is larger, resulting in improved SNR.

High Wave Number Resolution
Unlike dispersive IR, which requires a narrower slit to measure spectra with high wave number resolution, the wave number resolution of FT-IR can be easily increased by extending the moving mirror travel distance.

Possible to Expand the Measurement Wave Number Range
The wave number range can be extended from far infrared to visible by replacing the light source, beam splitter, detector, and window plate.

Other Information on Infrared Spectrophotometers

Preparation of Measurement Samples

Most compound identification using infrared spectrophotometers is done by the transmission method. The transmission method includes the use of powdered samples sandwiched between KBr plates (KBr plate method) or powdered samples mixed with KBr powder and solidified into a tablet form (KBr tablet method).

The sample is irradiated with infrared light, and the transmitted infrared light is analyzed. For samples with hygroscopic properties, powdered samples, and liquid paraffin are kneaded together to form a paste that is applied to a window plate (Nujol method). Samples on thin films, such as polymer compounds, can be directly irradiated with infrared light for measurement because infrared light penetrates the sample.

Note that there are some absorbers that cannot be analyzed depending on the preparation method. For example, in the KBr tablet method, it is difficult to evaluate the absorption band of the OH group due to the effect of moisture absorption of KBr, and in the Nujol method, the corresponding absorbent cannot be measured because of the absorption of liquid paraffin.

What Is an Infrared Camera?

An infrared camera is a specialized camera designed to detect objects in conditions where visible light is absent by capturing infrared light. It leverages the unique properties of infrared light for applications in thermography and low-light environments. Infrared light, characterized by its long wavelength, is emitted in response to temperature variations. When objects receive infrared light, their temperatures rise proportionally to the intensity of the infrared radiation.

By detecting these temperature changes induced by infrared light, infrared cameras can capture images of objects within their field of view.

Uses of Infrared Cameras

Infrared cameras have a wide range of applications, including thermography, body temperature measurement, and security systems. They are used in various contexts such as:

1. Thermography

Infrared cameras play a crucial role in thermography, enabling temperature monitoring and control in fields like medical thermometry and industrial processes.

2. Security Systems

These cameras are essential components of security equipment designed to operate effectively in low-light or dark environments, enhancing surveillance capabilities.

3. Industrial Inspections

In the manufacturing industry, infrared cameras are used for product inspection in environments with minimal or no illumination, ensuring the quality of manufactured goods.

4. Digital Photography Enhancement

In the realm of digital photography, infrared cameras contribute to improving image accuracy and precision.

When selecting an infrared camera, it’s important to consider factors such as detection accuracy, pixel count, size, ease of maintenance, and resistance to external factors.

Principles of Infrared Cameras

An infrared camera consists of essential components, including an infrared condenser lens, a detector element, and a processor. Thermopiles are commonly used as sensing elements, with multiple thermopiles embedded to correspond to the number of pixels required for information capture.

The role of the condenser lens is to selectively collect infrared light and direct it onto the thermopiles. When infrared light reaches the thermopiles, it causes temperature changes proportional to its intensity. These temperature-induced changes lead to the generation of an electric current in the thermopiles, which is subsequently amplified by an amplifier for each thermopile. The resulting data is processed by a central processing unit.

The intensity of infrared radiation determines the pixel’s shade in the captured image. Higher intensity corresponds to lighter shades, while lower intensity results in darker shades, allowing for object detection. Some infrared cameras incorporate cooling mechanisms for the thermopiles, while others feature advanced image processing algorithms to enhance detection accuracy.

Types of Infrared Cameras

1. Far-Infrared Camera Using Far-Infrared Radiation

Far-infrared cameras operate based on the detection of far-infrared radiation. These cameras can “see” heat emissions from objects, making them ideal for temperature measurement using thermography and similar applications.

2. Near-Infrared Cameras Using Near-Infrared Light

Near-infrared cameras, on the other hand, capture light in the near-infrared spectrum (780nm to 2,500nm). These cameras are designed to capture high-contrast images even under poor lighting conditions. They are commonly used in nighttime security systems and industrial camera applications.

What Is a Mass Spectrometer?

Figure 1. Image of a mass spectrometer

A mass spectrometer (MS) is an instrument that ionizes molecules within a sample and detects and identifies the mass-to-charge ratio (m/z) of the resulting ions.

The abbreviation “MS” is used internationally. When molecules are ionized by an ionization method, they are propelled by electrostatic forces.

A mass spectrometer is an analytical instrument that separates and detects ions in motion based on their mass-to-charge ratio (m/z) through electrical, magnetic, or other actions in a vacuum. The instrument primarily comprises a sample introduction section, an ion source, a mass separation section, and a detector.

There are several types depending on the ionization and mass separation methods, and they are used according to the measurement sample and application. Mass spectrometers are mainly used for sample identification, component analysis of unknown samples, and distinguishing and detecting isotopes.

Uses of Mass Spectrometers

Mass spectrometers are utilized for qualitative and quantitative analysis of a wide range of molecules, from low-molecular-weight compounds to high-molecular-weight compounds such as proteins and synthetic polymers.

Due to its effectiveness in identifying known substances and determining the structure of unknown substances, mass spectrometry is widely used in organic chemistry, biochemistry, and other chemical and biological fields. Specifically, it finds applications in research and development, quality control, analysis, and testing of various agricultural chemicals, pharmaceuticals, and naturally occurring compounds.

Recent advancements have enabled the ionization of proteins with large molecular weights, extending the use of mass spectrometers to the fields of life sciences and medicine.

Principle of Mass Spectrometers

Figure 2. Principle of a mass spectrometer

The fundamental principle of a mass spectrometer involves the following series of steps, with the mass spectrum displayed using m/z as the abscissa and detection intensity as the ordinate:

1. The sample is introduced into the instrument through the sample introduction section.
2. The sample is ionized by the ion source.
3. In the mass separation section, the sample is separated based on the different effects of magnetic and electric fields on ions according to their m/z, and detected by the detector.

Mass spectrometers can detect single-charged ions, which have only one charge, as well as multiply charged ions, fragment ions resulting from dissociation, or aggregate ions formed by the association of samples with each other. Peaks typically exhibit a unique distribution derived from the isotopic ratio of the original molecule.

Types of Mass Spectrometers

There are various types of mass spectrometers classified primarily by the combination of the type of ion source and the type of mass separator. Examples include “MALDI-TOF-MS” and “ESI-TOF-MS.”

1. Sample Introduction Section

Figure 3. Example of ionization source and mass separation part

Some mass spectrometers are combined with other instruments before the sample introduction section and are used in research and development and quality control. Examples include LC-MS combined with liquid chromatography, GC-MS combined with gas chromatography, and ICP-MS combined with inductively coupled plasma.

2. Ion Source

Electron Ionization (EI) Method
Accelerated electrons collide with thermally vaporized molecules (M) in a high vacuum. The electrons are then ejected from the molecule, producing radical cations (M+) called molecular ions.

Electrospray Ionization (ESI) Method

1. First, a sample solution is introduced into a capillary to which a high voltage is applied.
2. Atomizing gas (nebulizer gas) flows from the outside of the capillary to spray it, forming charged droplets.
3. As the charged droplets move, the solvent evaporates and the surface electric field increases, eventually causing the droplets to split when the repulsive force between the charges exceeds the surface tension of the liquid.
4. This process releases sample ions into the gas phase.

Matrix-Assisted Laser Desorption Ionization (MALDI) Method
This method involves mixing a sample with a matrix, such as an aromatic organic compound, to form a crystal. The crystal is then ionized by irradiating it with a laser. It is suitable for ionizing high-molecular-weight compounds such as proteins.

Fast Atom Bombardment (FAB) Method
This method ionizes sample molecules by high-speed collisions with neutral atoms in the presence of a matrix and a sample solution dissolved in an organic solvent.

Other methods include CI, FD, APCI, and ICP methods.

3. Mass Separation Section

Quadrupole (Q)
This method uses four electrode rods to apply a high-frequency voltage to ions from an ion source. The electrodes are subjected to DC and AC voltages to create an electric field that allows ions with a specific m/z to reach the detector.

This method can measure ions in the desired m/z range up to approximately m/z 4000.

Double-Focusing Type
This is a magnetic sector-type mass separator. In magnetic sector-type separators, ions pass through a magnetic field, altering their flight paths due to the Lorentz force. The double-focusing type combines magnetic and electric field sectors to achieve both velocity and directional convergence of ions.

Time-Of-Flight (TOF)
This method accelerates ionized samples with known electric field strength and detects the time difference between the arrival of each ion at the detector. It can measure ions across a wide mass range.

Other methods include Ion Trap (IT), Fourier-Transform Ion Cyclotron Resonance (FT-ICR), and Accelerator Mass Spectrometry (AMS).

What Is CAD Software?

CAD software refers to CAD systems used in the design of electrical, gas, HVAC, plumbing, and other equipment.

CAD stands for computer-aided design.

This means that something is created (designed) with the support and assistance of a computer.

Before the advent of CAD, CAD software was created and designed by hand, but now computers can be used to create CAD software.

Uses of CAD Software

CAD is employed across various industries, including construction, manufacturing, and interior design.

Among these, CAD software is used for designing building facilities such as electrical systems, gas infrastructure, air conditioning, and plumbing.

CAD that can be used regardless of the industry is referred to as general-purpose CAD.

Recently, there has been an increase in software applications that can be added to general-purpose CAD to provide the same functionality as dedicated CAD software.

Principle of CAD Software

CAD software is employed in various industries related to equipment, such as construction, civil engineering, and manufacturing, enabling smooth collaboration across industries.

CAD software features drafting, variant options, and annotation tools for creating highly accurate 2D drawings and documents.

They automate common tasks, streamline workflows, and provide an intuitive user interface.

All tools are available for architectural, manufacturing, electrical, plant, and other industries, with customizable features to enhance productivity further.

The mechanical design toolset includes over 700,000 machine parts, features, and symbols, simplifying the automatic generation of machine components and the creation of bills of materials.

The architectural design toolset includes over 8,000 architectural objects and styles for the automatic generation of floor plans, sections, and elevations, with support for IFC file formats.

The electrical controls design toolset encompasses over 65,000 electrical symbols for electrical control systems and can generate equipment layout drawings from schematic information.

The plant design toolset allows for process plant design and the integration of 3D plant design models to create piping rules and plant layouts.

The map 3D toolset integrates GIS and CAD data, providing access to spatial data in files, databases, and web services.

The facility design toolset comprises over 15,000 mechanical, electrical, and plumbing objects for HVAC, plumbing, and electrical design, including ducts and electrical cables.

The raster image processing toolset offers the ability to edit scanned drawings, convert raster images to DWG objects, edit, clean up, and move images, manipulate raster entities, and create vector shapes.

Notable Features of Modern CAD Software

Modern CAD software is characterized by their user-friendliness and expressive capabilities that allow users to convey their ideas directly.

The latest graphics technology is fully utilized, enabling rapid 3D model display and high-speed navigation.

The system also offers top-notch design performance, enabling designers to check for interference between components and peripherals and handle complex components to meet user requirements.

The result is high-specification CAD software that is truly ahead of their time.

Moreover, these latest CAD software boasts highly accurate data compatibility with other CAD systems and drawing compatibility with both old and new software versions, significantly improving operational efficiency.

Furthermore, some of the latest CAD software is compatible with various building information modeling (BIM) software for architecture with 3D capabilities, including drafting for mechanical and electrical equipment, and are utilized in numerous BIM projects.

CAD equipment and supply software are employed to model the HVAC, sanitary, or electrical systems of a building. From a single 3D model, it can generate a variety of architectural drawings, including floor plans, cross-sections, detailed drawings, electrical drawings, and HVAC drawings.

Furthermore, each of these drawing data is always linked to the CAD data for CG, so edits and modifications made to one drawing are reflected in the related drawings in real time.

BIM-Compatible Software

Creating BIM data in the early stages of an architectural project facilitates an accurate and prompt exchange of ideas among the client, designer, and constructor involved in the project.

It also helps reduce the time lost in the design process by enabling early detection of issues, such as interference between the building frame and equipment, or problems with construction procedures.

What Is a Recording Thermometer?

A recording thermometer is a device that automatically measures and records changes in air temperature over time also referred to as a self-registering thermometer.

There are two types of recording thermometers, each with a different mechanism.

One type utilizes the thermal expansion of metals, such as bimetals or Bourdon tubes, where the thermal expansion drives the pen of the self-registering device.

The other type uses the change in electrical resistance with temperature and employs a thermistor to convert the resistance change into an electrical current, which is then used to record the temperature with a recording thermometer.

Uses of Recording Thermometers

Recording thermometers are generally not very sensitive and may have a few minutes of delay when recording. Despite this, they can provide valuable information such as the time of maximum and minimum temperatures and the temperature change at any given time.

For this reason, recording thermometers are used in general weather observation, educational institutions, air conditioning systems, hospitals, warehouses, and other situations where temperature control is necessary.

Additionally, they find application in museums and art galleries to protect exhibits and are used in various settings such as chemical and food storage rooms in warehouses, agriculture, production plants for precision machinery like semiconductors and LSIs, and environmental laboratories.

Principle of Recording Thermometers

Bimetal thermometers consist of a sensor made from two pieces of metal with different coefficients of thermal expansion bonded together. Temperature changes cause warping of the metal, which varies with temperature and is used to measure temperature changes.

The Bourdon tube is a flat oval metal tube with a flat cross-section, sealed at one end and wound into a nearly circular shape, with one end fixed in place. As the temperature rises, the alcohol or ether sealed inside the tube expands, displacing the unfixed end of the tube, thus measuring temperature changes.

Recording thermometers that employ bimetals or Bourdon tubes use leverage to amplify the warping of the bimetals or the displacement of the Bourdon tube caused by temperature changes. This amplification is transmitted to a pen in the recording device, which records the data on chart paper (recording paper) wound around a drum rotating in a clockwork mechanism.

Thermistors are electronic components whose resistance changes with temperature variations. Thermistor thermometers measure resistance by passing a small amount of electric current through the sensor part’s metal, converting it into a temperature value. Since the measurement is conducted electrically, a digital display is also possible, and temperature changes can be recorded in a digital data logger.

What Is a Crusher?

A crusher is a device that crushes granular or clumped agglomerated materials to reduce their size.

It functions similarly to a shredder in that it shreds the material, but it plays a different role. In crushing, the material is crushed until it becomes a powder, so it is discharged as powder or granules, whereas in crushing, the material is discharged when it reaches a certain grain size, so it can be obtained as granules.

This function is used in the process of breaking down food products such as bread, biscuits, and snacks into flakes, and in the process of reducing granulated materials to the required grain size.

Uses of Crushers

Crushers are used to break up lumps of material to a certain size and to break up agglomerates of powder.

In the food industry, crushers are used to break up bread, noodles, cookies, snacks, etc., to a certain size, and have been used in the production of flaky curry roux, chocolate chips, dog food, etc.

In the manufacturing field, it is used to break down granulated materials to the required grain size to make flakes or to eliminate unintentional lumps. Installed downstream of the granulation process, the crusher can be combined with a sieving machine or other equipment that sorts the grain sizes to obtain materials with grain sizes within a certain range.

Principle of Crushers

Crushers are mainly composed of internally rotating blades and a screen-like mesh. Material fed into the crusher is repeatedly crushed by impacting the blades and sent downstream through the crusher. Through the above process, large-sized materials can be reduced to a certain grain size.

The grain size of the material obtained by the crusher is determined by the fineness of the mesh, but repeated collisions with the blades in the crusher before reaching the mesh can result in a material that is smaller than the required grain size. Therefore, downstream of the crusher, a sieving device is often used to sort the grain size, and the material with a smaller grain size is discharged or returned to the previous process. In some cases, the crusher and the grain size sorting device are combined as a unit.

The size of the blade and mesh required depends on the size of the material to be fed, the size of the grains required, the processing capacity, etc. Therefore, the equipment itself is often custom-made to some extent, and the size varies depending on the use of the equipment. Therefore, it is necessary to determine the specifications after the process and production capacity of the production line have been determined to some extent.