月: 2023年7月

What Is a Field Balancer?

A field balancer is a measuring instrument used for bearings and mechanisms of rotating machines and machine tools such as grinding and polishing.

By measuring the balance of a machine using a field balancer, the performance of the machine can be maintained and the manufacturing and maintenance of the product can continue to be performed with high accuracy. Field balancers equipped with a microcomputer can automatically calculate the degree of unbalance.

Uses of Field Balancers

Field balancers are used to measure rotating machinery and machine tools.

If the weight of rotating machinery is unbalanced around the rotating axis or on the bearings, vibration and noise will occur, reducing machining accuracy. Therefore, measuring and adjusting the balance is important to maintain product accuracy. Field balancers measure the balance during rotation and can display data on the amount of correction needed.

In polishing machines, eliminating unnecessary vibration of the machine can also reduce wear and prolong the life of the machine.

Principle of Field Balancers

A field balancer has a vibration sensor. By installing this vibration sensor at a highly rigid point near the bearing of the rotating shaft, the balance can be measured correctly.

What Are Hume Pipes?

Hume pipes are pipes made of reinforced concrete. They are also called reinforced concrete pipes.

Their name is derived from the surname of the brothers who invented them. The Australian Hume brothers invented a method of manufacturing hume pipes using centrifugal force in 1910, which was introduced to Japan in 1925.

The pipes are manufactured by filling a steel bar-reinforced formwork with concrete and rotating it on its axis using centrifugal force to compact and solidify it. This process strengthens the pipes and reinforces them against both external and internal pressure.

Hume pipes are mainly used as conduits in water systems, such as sewage pipes.

Uses of Hume Pipes

Hume pipes have three main industrial applications. PVC pipes are becoming more commonplace in open-cut construction, calling for an inner diameter of 500 mm or less due to their light weight and versatility. However, Hume pipes remain the preference in cases requiring high pipe strength and in main waterways requiring an internal diameter that exceeds 1,000 mm.

1. Sewerage Projects

Domestic wastewater generated in daily life flows through Hume pipes and is collected at sewage treatment plants. After purification at the sewage treatment plant, the water is reused or discharged into rivers.

2. Irrigation Projects

Irrigation is essential to agriculture. Hume pipes are used to channel the water used for irrigation. Two common irrigation methods are flood (or furrow) irrigation, and spray (or sprinkler) irrigation. In many cases, naturally occurring rainwater is not enough to supply water, so hume pipes are used to channel water from rivers and ponds to agricultural land.

3. Rainwater Management Projects

In recent years, the flow of heavy urban rainfall into rivers has caused significant flooding. This is largely due to urbanization and the decrease in farmland and forests, reducing the area of water-retaining land. Hume pipes are used as storm sewers and storage pipes in rainwater reservoirs and management facilities.

Principle of Hume Pipes

1. Production of Hume Pipes

Hume pipes are generally made out of reinforced concrete and manufactured using centrifugal force.

First, the steel reinforcement bars are assembled to create both longitudinal and circumferential reinforcement along the pipe. This reinforcement structure is then placed within a cylindrical outer frame which will define the perimeter of the Hume pipe.

Next, while rotating the outer frame, concrete is poured in several stages. The resulting centrifugal force presses the concrete against the frame where it solidifies, forming the pipe.

The centrifugal force generated during this process is 25 to 40 times greater than gravity, which causes the water in the concrete to separate. This results in a water-to-cement ratio of less than 30%, resulting in dense, robust concrete pipes.

2. The Advantages of Hume Pipes

The main advantages of Hume pipes are their high quality and strength, their low cost compared to other pipes, and the fact that the raw materials can be supplied domestically.

Hume pipes are approximately 30% stronger than vibro-compacted concrete pipes of the same composition.

Characteristics
Of Hume Pipes

1. High Quality and High Strength

Hume pipes are manufactured and checked for quality in controlled factories. They are manufactured to meet industry standards for dimensional accuracy, strength, and materials, and tested for resistance to bending and cracking.

2. High Apparent Specific Gravity

Hume pipes have a high apparent specific gravity, which is advantageous in the event of a disaster where low buoyancy is beneficial, such as soil liquefaction.

3. Minimal Water Leakage

Because of how well-compacted they are during manufacturing, Hume pipes exhibit minimal leakage during use.

4. Lightweight and Cost-Effective

Hume pipes can be made thinner than other concrete pipes used for the same purpose, making them lighter and more cost-effective.

5. Compatibility with Special Construction Methods

It is possible to enhance the corrosion resistance of Hume pipes. One simple approach is to use polyurethane elastomers as an internal coating. Another option is to use antibacterial Hume pipe concrete to mitigate bacterial growth.

There are also techniques for enhancing flexibility to thrust pipes, so they can be used in curved installations.

What Is a Hand Press?

A hand press is a manually-operated tool used to perform tasks such as sheet metal work. They feature a handle or lever that the operator uses to apply localized pressure to the target object.

When using a hand press, the target object is placed in the designated area, and pressure is applied by lowering the handle from above. By switching out the dies affixed to the press, various tasks including cutting, hole punching, and engraving can be carried out. The amount of pressure that can be applied varies depending on the type and size of the press, and there is a range of specialized dies available.

Uses of Hand Presses

Hand presses can be used for anything that can be processed by applying pinpoint pressure to the target part of an object using vertical force. Examples include press-fitting pins, bending thin metal, and processing thin bars. Given their history of use for printing, hand presses can also be used for printing on plastic materials and metal sheets.

In general, hand presses are often used to perform bending and cutting tasks in processes such as assembly or small lot manufacturing. Other uses include attaching fasteners such as rivets and hooks, press-fitting bearings, and crushing.

Principle of Hand Presses

Hand presses feature a detachable, replaceable lever or handle and a spring-loaded core rod housed in an iron body. They are manually operated by lowering the handle or lever to apply local pressure to an object.

When processing with a hand press, the core rod to which the lever is attached is pressed downward, applying targeted, non-dispersed pressure to the object. The spring attached to the core rod ensures that force is applied slowly, requiring minimal effort from the operator.

Handles and levers come in various forms, ranging from staple-like shapes to steering wheels. Hand presses should be selected based on the desired amount of pressure. And because they are susceptible to damage, hand presses must be used on level surfaces.

Other Information on Hand Presses

1. Advantages of Hand Presses

Due to their simple structure, hand presses offer two main advantages. The first is that they are easy to maintain, allowing for long-term use. The second is that they can be operated without electricity, reducing energy consumption and costs.

2. The History of Hand Presses

The history of hand presses dates back to ancient times and extends to the 20th century. The Albion printing press, first manufactured in the 1820s, became widely used until the 1930s. The hand press was modeled after the Albion press, initially for the printing of postcards during the 1910s and 1920s.

The basic function of those early hand presses remains the same in modern hand presses: to apply pressure to imprint an object. But modern presses have undergone many engineering improvements, and can now also be used for other tasks, such as inserting pins and bending or cutting thin rods.

In the modern era, many hand press manufacturers have emerged, offering presses with capacities ranging from 500 kg to 12 tons. Specialized presses operated by steering wheel-like handles, as typified by the Exxon Press, have also been developed.

The most well-known hand press is the Handy Press. It resembles a stapler, which most people are familiar with, making it extremely easy even for first-time users to operate.

What Is a Diamond Saw?

Diamond saws are tools with diamond particles embedded in the blade.

They are low-impact tools that produce minimal dust and can cut complex shapes, small objects, and brittle materials, making them suitable for a wide range of applications. In research and development settings, their delicate, high-precision cutting makes them useful for cutting small samples. But they can even be used in large-scale construction projects, such as the demolition of structures.

There are many types of diamond saws, including cable saws and circular saws. Each type has a different use case. While cable saws are well-suited for cutting in tight spaces and handling complex shapes, circular saws are suitable for general cutting.

Uses of Diamond Saws

Boasting exceptional cutting power and precision, diamond saws have a wide range of uses. They can cut ceramics, glass, porcelain, tiles, reinforced concrete, and other tough materials. They can be used across many fields, from research and development to production and demolition, and come in a variety of shapes and sizes, from tabletop to large-scale models.

It is important to select the most appropriate diamond saw for the size of the material to be cut. Circular saws can safely achieve a smooth cut, even on hard materials.

Cable diamond saws facilitate cutting the cutting of fixed objects without imposing any load. This makes them suitable for cutting brittle and hard materials alike without causing damage.

Principle of Diamond Saws

Diamond saws are characterized by their high-precision cutting abilities and are named for the diamond particles embedded in their blades. Diamonds have extremely high hardness, and this property makes it possible to generate the force needed to cut through hard materials.

The size and density of the diamond particles also influence the function of both cable and circular diamond saws. Cable saws cut using reciprocating motion, while circular saws cut using rotation. What the two have in common is the necessity to make direct contact with the object to cut through it.

Furthermore, the cutting speed can be controlled by adjusting the cutting load, facilitating the precise cutting of various hard materials at the appropriate load and speed required to prevent damage and malfunctions.

The overall efficacy of diamond saws relies on both the hardness of the diamond particles and accurate cutting load and speed. The correct balance of these factors provides the exceptional cutting ability and precision that diamond saws are capable of.

Types of Diamond Saws

There are three main types of diamond saws: cable diamond saws, circular diamond saws, and segmented diamond saws.

1. Cable Diamond Saw

Cable diamond saws make use of a cable embedded with diamond particles. Since cutting is performed using a reciprocating motion, they are effective in tight spaces and for cutting complicated shapes.

They can also be used without imposing a heavy load on the target object, making them suitable for both durable and brittle materials.

2. Circular Diamond Saw

Circular diamond saws use a circular blade embedded with diamond particles. They cut using a rotational motion, making them suitable for general cutting work and achieving smooth cut surfaces.

3. Segment Diamond Saw

Segmented diamond saws feature diamond-embedded segmented blades embedded. This allows for effective heat dissipation while cutting, making them suitable for high-speed cutting and prolonged use.

Additionally, the segmented blade reduces friction against the object being cut, making cutting more efficient.

What Is Sikkens Paint?

Sikkens Paint is a brand of paint produced and sold by an art material manufacturer headquartered in the Netherlands.

It was developed by Sikkens in 1792 and is used worldwide. Their wood paints are the most commonly used, but their product line includes paint for vehicles such as airplanes, space shuttles, and cars, as well as other applications.

Sikkens paint is used not only as a decorative surface coating, but also to prevent oxidation and provide water resistance, protecting surfaces and prolonging the lifespan of products.

Uses for Sikkens Paint

Sikkens paint is often used to minimize the deterioration of log homes, which are made entirely of wood.

Building exteriors are exposed to wind and rain, so if no maintenance is performed, regular paint needs to be reapplied approximately every two months. But Sikkens paint requires maintenance as infrequently as every three years, sometimes even less.

Known for its superb ability to protect surfaces, Sikkens paint is trusted and used by professional contractors.

Principles of Sikkens Paint

Wood protective paints sold at home improvement stores are often diluted with a specific liquid before application. But these coatings tend to evaporate quickly, requiring multiple applications and subpar surface protection.

Sikkens paint can be used without being diluted, allowing it to penetrate the wood and protect the surface.

What Is a Container Washer?

Container is a general term for the many types of specialized vessels used in various industries.

Container washers are machines that clean these vessels more efficiently and hygienically than human operators can. When washing by hand, there is a limit to human efficiency, and it is difficult to use high temperatures and harsh detergents, which can lead to uneven cleaning.

Container washers, on the other hand, can perform high temperature cleaning and utilize cleaning agents that might be harmful to humans, resulting in uniform cleaning without any worry about labor costs or manpower.

Additionally, when cleaning manually, human washers are likely to use a different amount of water during each job. But container washers use a fixed amount of water, which can prevent waste and reduce costs.

Uses of Container Washers

Container washers vary in size and performance, so it is important to select the most appropriate type for the intended use.

First, consider how many containers need to be cleaned at once to determine whether a small batch-type washer or large conveyor-type washer would be more appropriate.

Batch-type container washers are compact to save space, while conveyor-types are large and specialized for high-volume processing. Conveyor washers are further divided into those that only wash and those that both wash and dry containers. Industries that use container washers are diverse, including everything from food-related industries such as seafood, meat, food, and beverage producers, to hygeine-related industries such as sanitation.

Principle of Container Washers

Container washers provide high-quality cleaning by optimizing the amount of time, water pressure, water volume, water temperature, and chemical detergents used according to the application and container material.

There are two levels of water pressure used for cleaning: low-pressure and high-pressure. Low-pressure cleaning is effective for washing large areas. At high-temperatures, it is highly-effective for sanitation, but not suitable for targeting cleaning.

High-pressure cleaning, on the other hand, can break down dirt by spraying it with a high-pressure jet of water. So it’s very effective for targeting tough stains and reduces water consumption, but it consumes excessive amounts of energy and is prone to uneven cleaning.

What Is an Extruder?

An extruder is a processing machine that can process raw materials such as food, pharmaceuticals, plastics, rubber, and ceramics.

Extruders can simultaneously process and convey raw materials. Processing methods include heating, pressurizing, mixing, and extrusion. Extrusion, in particular, is used in the production of plastics and rubber because it heats the raw material, applies pressure, and extrudes it into a consistent shape. Extruders are available in a wide variety of nozzle shapes, which makes them viable for a wide range of shapes and applications. This allows the production line to be easily changed to meet demand, making them suitable for small-lot, multi-variety production.

Extruders are, however, subject to wear, overheating, and other problems that occur during processing. Therefore, use with certain materials requires a high level of skill and expertise. Furthermore, post-processing cleaning can require substantial additional equipment.

Uses of Extruders

Extruders have a wide range of applications, including processing food, pharmaceutical, and other raw materials by adjusting their shapes and other properties.

1. Food Processing

First, let’s look at the use of extruders in food processing. One way they are used is to process protein-based ingredients like soy, restructuring them to modify their texture, resulting in products like textured vegetable protein (TVP), also known as soy meat. They’re also used in the production of puffed food, candy, pet food, and grain products such as oatmeal.

2. Pharmaceutical Production

Extruders are widely used in the field of pharmaceutical production. They can be used to convert powdered pharmaceutical ingredients into tablets. The shape and size of the tablets can be adjusted based on the required dose.

3. Other Fields

Extruders are used in several industries, including cosmetic manufacturing and the production of fuel, paint, and resin. Facilities where they are used include laboratories, food factories, pharmaceutical plants, chemical plants, and resin factories.

Principle of Extruders

An extruder is a machine that processes a raw material while mixing it with a liquid.

The extruder consists of a feed section, a screw section, a barrel, and a die. The material enters through the feed section, is mixed by the screw, passes through the barrel under pressure, and is pushed out through the die. Since the material can be transported and processed at the same time, extruders operate very efficiently.

By changing the type of screw being used and adjusting the rotation speed, it is possible to calculate how long the material will remain inside the extruder and modify the extrusion pressure. The shape can be freely changed to produce thin sheets, squares, circles, and other shapes.

Types of Extruders

There are five types of extruders: single-screw extruders, twin-screw extruders, batch extruders, continuous extruders, and cold extruders.

1. Single-Screw Extruder

Single-screw extruders push out raw materials with a single screw. They are mainly used in small-scale processing plants and research institutes, and are characterized by their relatively low cost.

2. Twin Screw Extruder

Twin-screw extruders use two screws to extrude raw materials. They have a high processing capacity and, depending on the shape of the product, can produce more uniform products. As such, they are used in the production of foods and pet foods that require mass production.

3. Batch-Type Extruder

Being compact, batch-type extruders are sometimes used by small food manufacturers and research institutes. They are suitable for research and development because of their simple structure and the visibility of processing operations.

4. Continuous Extruder

Continuous extruders are suitable for mass production and have high processing capacities. In particular, large continuous extruders are characterized by their extremely high productivity.

5. Cold Extruder

Cold extruders with adjustable pressure and temperature are also available. Because they extrude at low temperatures, they can retain the nutrients in the ingredients, making them suitable for processing health foods, snacks, etc.

What Is Polyurethane Waterproofing Coating?

Polyurethane waterproofing coating is a material applied to balconies, the common facilities of condominiums, and other places where waterproofing is required.

Polyurethane waterproofing coating is often used because it is relatively inexpensive, easy to work with, and can be applied to many surfaces.

Uses of Polyurethane Waterproofing

Polyurethane waterproofing coating is used in many structural elements, including rooftops, balconies, open corridors in apartment buildings, and stairways. Polyurethane waterproofing coating used to waterproof these spaces can be broadly divided into two types: one-component sealants and two-component sealants, the latter being used after mixing with a hardener.

1. Single-Component Polyurethane Waterproofing Coating

Single-component polyurethane waterproofing coating is used to waterproof balconies and similar spaces because it is very easy to work with.

2. Two-Component Polyurethane Waterproofing Coating

There are two types of two-component polyurethane waterproofing coatings: manually-applied and sprayed. With manually-applied coatings, the base compound and curing agent are mixed and applied, then cured at the temperature of the surrounding environment. This type of coating has a rubbery, elastic surface and is commonly used for waterproofing rooftops and balconies.

The manufacturing of spray-type polyurethane waterproofing coatings started with the development of rigid polyurethane. It is applied by spraying the polyurethane and a curing agent while mixing them in a specialized machine. Since it begins to cure in less than a minute after application, it is commonly used in sloped areas and heavily-trafficked corridors and stairways.

Rigid polyurethane waterproofing coating is also used in civil engineering applications, such as bridges, thermal storage layers, and underground waterproofing. The use of polyurethane waterproofing can protect structures from water, protect concrete from salt damage and neutralization caused by carbon dioxide gas, and prevent concrete spalling. It is also used on roads to prevent deterioration caused by expansion and contraction due to vehicle traffic and snow-melting chemicals.

The spraying method also makes it possible to apply coating even in places that may not be sufficiently dry, such as uneven surfaces and underground. Furthermore, rigid polyurethane waterproofing coating has excellent chemical resistance, heat resistance, crack tracking, and abrasion resistance, and is used for coating sewage-related facilities, offshore structures, steel tanks, structures, etc.

Principle of Polyurethane Waterproofing Coating

Polyurethane waterproofing coating is a generic term for polyurethane resin or polymer. Polyurethane has exceptional properties for pressure resistance, waterproofing, and elasticity.

1. Single-Component Polyurethane Waterproofing Coating

Single-component polyurethane waterproofing forms a waterproof film via a polymerization reaction between isocyanate (the base compound) and polyol (the curing agent). When single-component polyurethane waterproofing is applied, the isocyanate group-containing base reacts with moisture in the air to cure at the ambient temperature, so it takes about 24 hours to cure.

2. Two-Component Polyurethane Waterproofing Coating

Two-component coatings can be further classified into two types: manually-applied and sprayed.

Manually-Applied Coatings
Manually applied coatings require the mixing of a polyisocyanate-based base compound and polyol-based curing agent before application. The base compound is a viscous liquid containing isocyanate groups at the molecular ends of the polyurethane prepolymer. The curing agent is a paste-like material containing amines, polyols, fillers, plasticizers, and stabilizers, which react with the isocyanate groups of the base compound.

When working with manually-applied two-component polyurethane waterproofing material, a pressure pump is used to dispense the material, eliminating the need for mixing equipment. The advantages of this system include improved work efficiency, less unloading work, and significant waste reduction. The mixing is done automatically, supplying a uniformly-blended coating with no risk of mixing defects.

Spray-on Coatings
Spray-on two-component polyurethane waterproofing coatings using rigid polyurethane also utilize isocyanate and polyol to form a waterproofing film. Spray-on coatings are characterized by the fact that the base compound and curing agent are each pumped under high pressure, mixed in the spray gun, and sprayed on.

The advantage of this type is that it hardens quickly, so the same material can be used for both flat and vertical surfaces. However, since spraying machines vary between manufacturers, it is essential to seek guidance from the waterproofing material manufacturer before installation.

Other Information on Polyurethane Waterproofing

1. Polyurethane Waterproofing Coating Application Methods

Single-component and manually-applied two-component polyurethane waterproofing coatings are all made by solidifying the liquid material to form a waterproofing membrane. The advantage of this process is that it’s relatively simple. In practice, a priming layer, which enhances adhesion, is applied to the surface before waterproofing, and the polyurethane coating is then applied on top of the primer.

However, when applied to some surfaces, such as concrete, there is a disadvantage in that cracks in the concrete are transferred to the coating, which could potentially lead to rupture. Another disadvantage is that water vapor retained in the substrate of the surface could cause swelling and other issues.

As a result, a construction method combining ventilation buffer sheets and polyurethane was developed. In this approach, a primer is applied on top of the substrate, covered with a ventilation buffer sheet, and the polyurethane waterproofing coating is applied and cured on top. With the sheet placed between the waterproofing material and the substrate, it is possible to prevent ruptures and swelling due to moisture in the substrate. Since the adoption of this method, polyurethane waterproofing, which used to be used primarily for small-scale renovations, has become viable for use in new construction and large-scale waterproofing ventures.

2. Topcoat Used for Polyurethane Waterproofing

Just as in painting, a topcoat is a material applied as a finishing layer after the application of a polyurethane waterproofing coating.

One of the drawbacks of polyurethane waterproofing is the tendency of the coating to discolor when exposed to ultraviolet light. Also, because of how they cure, there is a risk of cracking and deterioration. A topcoat helps protect the waterproof coating from ultraviolet rays and prevent the above-mentioned deterioration.

Additionally, since polyurethane waterproofing coatings have adhesive properties, dust and dirt can easily adhere to the surface if left untreated. This can build up and be difficult to remove, so a topcoat also serves to mitigate the adhesion of dirt.

Topcoats both address the weakness of polyurethane waterproofing coatings and mitigate their deterioration. Therefore, applying a topcoat is a critical finishing step in the overall application process.

3. Calculating Quantities for Polyurethane Waterproofing Coating Application

The application quantity refers to how much material is needed to optimize the performance of the polyurethane waterproofing coating.

If the specified application quantity is 0.7 kg, for example, 7 kg will be needed to cover a 10 m2 installation area. But in practice, the surface may be uneven, affecting the exact measurements of its area and its shape. Failing to consider this could result in a significant miscalculation of how much material is needed. As such, considering the shape and surface irregularities when calculating application quantity is crucial.

What Is Celite?

Celite is a porous solid made by calcining siliceous soil with sodium carbonate.

It is positioned as a type of siliceous soil, and some products are sold under the brand name Celite® as siliceous soil itself. Its main constituent is silicon oxide, and it also contains aluminum oxide, iron oxide, aluminum oxide, and magnesium oxide.

Uses of Celite

Celite’s raw material, siliceous soil, is a fossil of silicea, one of the phytoplankton. The fossilized phytoplankton has microscopic holes in it, which Celite uses for filtration.

1. Industrial Applications

Even highly viscous materials such as fruit juices, pharmaceuticals, gelatin, wastewater, and oil can be filtered relatively stably for long periods of time. In industrial applications, the most commonly used method is to mix the filter media with Celite water and pre-coat it with a thickness of approximately 2 mm between filter papers to maintain the filtration speed.

2.Laboratory Applications

Laboratory applications are also used for filtration of specimens that are too clogged with filter paper. substances are filtered at different rates.

Characteristics of Celite

Celite is made from fossilized algae (phytoplankton) called cassiterite, which grew on the earth tens of thousands to tens of millions of years ago. Algae still grow in the oceans, rivers, and lakes of the world today.

Like seaweeds, they are generally members of the algae family. The term “siliceous algae” is used especially for those with a glassy shell around their cells. Siliceans are single-celled photosynthetic organisms that grow everywhere on earth. in size and take in silica from the water, creating numerous 0.1 to 1.0 micrometer pores that lead inside and out.

Then, when the siliceous dies and settles in large quantities and becomes a fossil, it becomes siliceous soil, leaving only its silica remains. When sodium carbonate is added to this siliceous soil and calcined, it becomes Celite.

Types of Celite

Celite is divided into several types depending on its filtration performance. The grade commonly referred to as silica clay, is also marketed under the name Celite®, and is used for liquids with smooth filtration.

Grades used for difficult-to-filtrate liquids, gels, and colloids are 503, 535, and 545 in Japan. Generally, 535 and 545 are widely used.

1. Celite No. 503

• Particle size : 12 to 20 micrometers
• Flow rate ratio : approx.900
• 150 mesh residual : 9%.
• Applications : Used for liquids that are relatively difficult to filter.

2. Celite No. 535

• Particle size : 20 to 30 micrometers
• Flow rate ratio : approx. 1,350
• Residual at 150 mesh: 9%.
• Applications : Used for beer, fruit juices, agar, antibiotics, enzymes, polymers, alginic acid, crude sugar, alkali solutions, animal oils, glycerin, sugar solutions, treated water, etc.

3. Celite No. 545

• Particle size : 25 to 40 micrometers
• Flow rate ratio : approx. 2,160
• Residual at 150 mesh : 12%.
• Applications : Used for raw materials with high viscosity and especially large amount of foreign matter, such as creams, pectin, mineral oil, agar, pine resin, latex, tar, catalysts, etc.

Other Information on Celite

1. Legal Regulations on Celite

CAS No. 68855-54-9 is added as silica soil.

2. Principle of Celite Filtration

Filtration is the process of removing foreign matter through a filter medium with small holes. In the case of filter paper, substances are easily adsorbed by the cellulose and get trapped, gradually clogging the filter. Silicon dioxide, the main component of Celite, is less likely to adsorb substances.

When Celite is laid on top of the filter paper, substances are prevented from adsorbing and clogging the filter paper, and the fine particles that cause the filter paper to clog are trapped by Celite, resulting in smooth filtration and time savings. , the filtration speed can be increased again by scraping the surface.

What Is a Digital Potentiometer?

A digital potentiometer is an integrated circuit that digitally controls the sliding element (wiper) of a variable resistor, simulating the function of an analog potentiometer.

Unlike analog variable resistors, digital potentiometers do not have mechanically-moving sliding parts, making them structurally robust, resistant to failure, and highly reliable for long-term use. When combined with a microcontroller or other device and mounted in an analog circuit, the amperage can be automatically adjusted while freely controlling the resistance value.

Uses of Digital Potentiometers

Digital potentiometers are used in audio equipment and digitized home appliances, such as AI speakers and LED dimmers. Since they can be described as digitized variable resistors, they are used as an alternative to analog circuits with sliding parts.

For example, they can be used to digitally control the volume adjustment of audio equipment or the brightness and contrast adjustment of displays, which used to be controlled by physical dials. As smart home appliance technology has progressed in recent years, there is a growing demand for digital control of analog values, driven in part by compatibility with AI speakers.

Principle of Digital Potentiometers

The principle function of digital potentiometers lies in the operation of a variable resistor. The resistor’s sliding wiper, once mechanically-operated, is now controlled by a Once mechanically-operated by a sliding wiper is now switched and controlled by a combination of a digital circuit and a resistance.　

The analog circuit consists of a series of fixed resistors, and the connection points are switched by COMS transistors. This allows the variable resistor to switch resistance values in response to signals from the digital circuit part.

The digital circuit consists of an up-down counter, a nonvolatile memory such as EFPROM, and a decoder. When the desired resistance value is input, it is written to the counter and written to the nonvolatile memory.

This information is read out by the decoder, and the CMOS transistor corresponding to that value is switched on. The value of the variable resistor can be set quasi-statically by digital input. External inputs are stored in nonvolatile memory, so the information is preserved even after the circuit is turned off.

Other Information on Digital Potentiometers

1. Replacement of Analog Adjustment Trimmers

Nowadays, as typified by digital home appliances and IoT electronic devices, analog mechanical adjustment is being replaced by programming-based digital control. In the case of analog adjustment, the final step in the production line is manual adjustment before shipment, but by using digital potentiometers, automatic adjustment is possible through microcomputer control and other means.

Automatic calibration is also possible, increasing equipment precision. Unlike mechanical analog adjustment trimmers, adjustment by outside parties unfamiliar with the digital control code is impossible, providing significant security benefits.

Because of this high level of reliability, digital potentiometers have recently been widely used in entertainment equipment, where volume and LED contrast are important.

2. Digital Potentiometer Digital Control Method

The control interfaces for digital potentiometers usually include the Serial Peripheral Interface (SPI) interface, I2C interface, and UP/DOWN interface. Furthermore, in applications where a digital potentiometer requires continuous variation similar to a D/A converter, attention should also be paid to the clock frequency during digital control.

The maximum frequency is typically about 3 MHz, but it is important to check the product specifications in advance. Application software for these controls is usually available from the manufacturer, and technical support is also provided if necessary.

In some cases, a development support kit including a Graphical User Interface (GUI) is also available for users who wish to develop their own programming software.