月: 2023年1月

What Is a High-Pressure Hose Fitting?

A high-pressure hose fitting is a component (fitting) at the end of a hose to which a high-pressure hose is connected.

Like general hose fittings, there are different types of high-pressure hose fitting, depending on the application.

The hose fitting is selected according to the size (outer diameter) of the hose and its sealing performance (leakage) against fluid pressure. Especially in the case of high-pressure hoses, leakage of high-pressure fluid is dangerous, and a connection method with high-sealing performance must be used. Therefore, a screwed-in type with a tapered pipe thread, or a flanged type for higher pressure, is used.

Uses of High-Pressure Hose Fittings

High-pressure hose fittings are used to connect hoses to each other and to piping and equipment.

High-pressure hose fittings used for high-pressure fluids, such as steam, chemicals, gases, etc., are often threaded or flanged.

When used for air, where a small amount of leakage is not a concern, a coupler, or a one-touch type, may be preferred for its ease of connection and disconnection, making it more convenient to work with.

The most suitable high-pressure hose fittings material should be selected according to the type of fluid used and the environment in which it is used. In particular, selection should be made in consideration of pressure resistance, heat resistance, and corrosion resistance.

Principle of High-Pressure Hose Fittings

The principle of high-pressure hose fittings is the same as that of ordinary hose fittings.

In the case of the threaded type, the tapered male and female threads are tightly sealed together. By screwing in deeply, the tight fit gradually becomes stronger, and higher sealing performance can be obtained.

In the case of a flange type, the joint surfaces of the flanges are tightly sealed against each other. A gasket is generally inserted between the flanges to increase the adhesiveness of the flanges. The flanges are tightened with bolts and nuts to increase and maintain the adhesion. In this case, the bolts and nuts must be tightened evenly.

For this reason, bolts and nuts are generally tightened diagonally rather than in sequence. It is also important to tighten the bolts and nuts at the specified torque value for the gasket material and bolt/nut. The tightening torque is gradually increased in diagonal order until the required tightening torque value is reached.

In the case of screwed-in or flanged type for high-temperature fluid, the tightening of the threaded part may loosen due to thermal expansion after the actual flow of high-temperature fluid. In such cases, it is necessary to re-tighten the threaded part for the screwed type and the bolt/nut for the flanged type.

What Is a Multicolor Paint?

Multicolor paints are a type of paint composed of multiple granular chips of different colors and shapes.

These chips, when mixed, create a three-dimensional effect and texture on painted surfaces, resembling natural stone or wood textures.

Here are the key applications, features, and types of multicolor paints:

Applications of Multicolor Paints

1. Architectural and Interior Design

Used on interior and exterior surfaces to create unique designs and textures, especially effective in commercial spaces.

2. Arts and Crafts

Utilized in artwork and handicrafts to add depth and expression, offering artists versatile means of creative expression.

3. Automobile and Vehicle Painting

Customized for automobiles and motorcycles to create eye-catching designs, particularly popular in custom car shows.

4. Industrial Product Design

Applied to industrial products for exterior design to enhance attractiveness and differentiation in the market.

Features of Multicolor Paints

1. Versatile Design

Creates rich colors and intricate patterns, offering vibrant and visually appealing designs.

2. Three-Dimensional Effect and Texture

Adds depth and texture to surfaces, providing a realistic and tactile experience.

3. Environmental Friendliness

Thinner paint thickness contributes to resource conservation and environmental sustainability.

4. Design Flexibility

Allows for infinite design variations by changing chip size and arrangement, catering to different tastes and styles.

5. Appearance Under Lighting

Produces complex light reflections under illumination, creating dynamic visual effects.

Types of Multicolor Paints

1. Colorful Chip Type

Contains chips of different colors, creating vibrant patterns, primarily used in art and design.

2. Natural Pattern Effect Type

Reproduces stone or wood patterns using chips of various shades and patterns, commonly used in architectural and furniture decoration.

3. Glossy Pattern Type

Creates glossy, three-dimensional patterns using specially treated chips, popular for decorative items and accessories.

4. 3D Effect Type

Produces three-dimensional effects through chip shape and arrangement, ideal for advertisements and signboards.

5. Metallic Pattern Type

Imitates metallic shine and texture using metallic finish chips, often used in customizing cars and manufacturing decorative items.

What Is a Heat Resistant Coating?

Heat-resistant coatings are paints that resist heat.

Heat-resistant coatings have a temperature resistance of 100°C or higher, whereas general paints have a temperature resistance of 70°C to 100°C. The resin used in general paints differs from that used in heat-resistant paints. Heat-resistant coatings are made of silicone resin, which does not decompose easily when heated.

In addition, “body pigments” are added to increase the strength of the paint film, and the heat resistance temperature differs depending on the type of pigment.

Applications for Heat Resistant Coatings

Heat-resistant coatings can be used in temperatures from about -50°C to about 600°C. They are both cold and heat-resistant. Therefore, they can be used primarily in areas exposed to high temperatures. Familiar examples include coatings on stoves, camping equipment, pots and pans, motorcycle mufflers, incinerators, and boilers.

In addition to being resistant to heat, they can also be used in changing climates. However, since heat-resistant temperatures vary depending on the pigment used, it is necessary to check the temperature of the area where the paint will be used and select the right paint for the application.

Principle of Heat Resistant Coatings

Heat-resistant coatings are made from a silicone resin base, containing body pigments to increase strength, anti-corrosion pigments, color pigments, solvents, additives, and other materials. Each of the raw materials in heat-resistant coatings is heat resistant. Resins are the backbone components related to the performance of the paint.

Color pigments are used as reinforcing materials to prevent rust. Additives support the heat-resistant raw materials and stabilize the paint film. Solvents are necessary for clay conditioning. They enhance the fluidity of the ingredients and improve the workability of the paint.

The process of applying heat-resistant coatings is almost the same as for general paints. To ensure that the paint adheres to the material before coating, a surface preparation called “kerene” is important. If heat-resistant coatings are applied without surface preparation, the paint will not adhere to the material and will easily peel off.

Baking drying at 200°C for approximately one hour is required. Parts with heat-resistant coatings are forced-dried using electric heaters, burners, or drying ovens. However, rapid heating may cause the paint film to react and produce large amounts of gas.

Types of Heat Resistant Coatings

Like other paints, there are several types of heat-resistant paints, such as brush-on, spray, and marker-pen types. The brush type is suitable for painting large objects over a wide area, such as boilers and incinerators in factories. The spray type is suitable for curved surfaces and intricate parts such as motorcycle mufflers. Markers can be used for small areas, such as marking areas that are subject to high heat in laboratories, factories, and other production sites.

Depending on the pigments and additives mixed in addition to the different types of application methods, there are also products with additional performance characteristics such as water resistance, acid resistance, and rust resistance. Rust-resistant paints are used in outdoor facilities, while acid-resistant paints are used to protect the interior of plant equipment from combustion gases and other acids and heat.

Generally, silicone resins are available for heat-resistant coatings. Fluoropolymers are mainly used for frying pans, hot plates, and other cooking utensils, as they must be made of ingredients that are not harmful to the human mouth.

How to Select Heat Resistant Coatings

A wide variety of heat-resistant coatings are available and can be selected according to the intended use. Heat-resistant coatings are available in a wide variety of colors and can be selected to match the color of the area to be painted to achieve a natural look. It also has the effect of preventing discoloration due to deterioration. The appearance changes depending on the luster, which can be selected based on the gloss of the heat-resistant coatings.

For painting over a large area, a large-volume type painted with a brush is suitable. In many cases, applications are listed, such as for motorcycles or cast iron stoves.

In addition to products with heat resistance temperatures from 300°C to 600°C, some are designed for commercial applications with heat resistance temperatures of 1,000°C or 2,000°C. Some types have improved corrosion resistance, durability, and adhesion when coated with a special primer, and their performance varies with heat-resistant coatings. Drying time after painting also varies, so it is necessary to check the drying time along with the performance.

What Is a Rust Converter?

Rust converters are agents that convert red rust to black rust and inhibit the progress of rust.

Red rust is the reddish-brown color commonly known as rust, and if left unchecked, rust will spread and corrode to rags. On the other hand, black rust is an oxide film that forms on the surface of iron and stops the progress of rust.

Usually, there are treatment methods such as “polishing with sandpaper” or “removing rust with a rust remover,” both of which are labor-intensive methods. Rust converters can be applied directly to the rust with a brush to change the red rust to black rust and prevent the rust from progressing.

Uses of Rust Converters

Rust converters are used in areas prone to rust because of their role in inhibiting the progress of rust. It is especially applied when it is difficult to remove rust by polishing. For example, it can be used on large objects such as automobiles, motorcycles, and outdoor fences.

Other than that, it is suitable for rust treatment on tanks, bridges, agricultural machinery, railroads, ships, gates, steel stairs, shutters, and other areas where rust is difficult to remove. However, since rust converters will look black with black rust after application, they are used in areas that are difficult to see or where the appearance is not a concern.

Principle of Rust Converters

Rust caused by wind, rain, and humidity is red rust. When red rust occurs, the surface becomes wavy, allowing moisture and oxygen to penetrate between the waves, and if left unchecked, further corrosion can progress to the point where the metal is torn to shreds.

Rust converters contain chemicals that are effective against red rust and react with air, chemicals, and water to turn the rust into black rust. Black rust is rust that occurs when steel is heated to high temperatures. Unlike red rust, black rust is impervious to oxygen and water.

Rust converters can prevent steel corrosion, but they cannot remove the rust itself. It only changes the composition of the rust and prevents it from getting worse. To remove rust, use a rust remover or rust removal cream. Rust converters will turn black and should not be used on visible areas.

Oil-based rust converters have a chemical-like odor, which can be strong if used in an enclosed space. There is a risk of ignition in a fire-hazardous area, and work should be performed in a well-ventilated environment or outdoors.

Structure of Rust Converters

When metal atoms on the surface of metal undergo a redox reaction with moisture and oxygen, rust is formed as a corrosive substance. There are two types of rust: red rust and black rust. Rust converters chemically change red rust to black rust.

1. Red Rust

Red rust is iron hydroxide or ferric oxide, which is formed when iron atoms naturally combine with water and oxygen. Red rust is water-soluble and easily retains moisture, and once red rust is formed, the reaction proceeds one after another.

2. Black Rust

Black rust refers to ferric tetroxide. Because of its high density, black rust is hard to adhere to the surface and the reaction does not progress to the interior. Black rust can be obtained by heating iron.

Types of Rust Converters

There are two types of rust converters: oil-based and water-based.

1. Oil-Based Rust Converters

It forms a durable and strong film and is suitable for outdoor areas of buildings and exterior surfaces of vehicles. It does not change with weather conditions and can cover rusted areas with a thin film, which keeps its effect for a long time.

However, because it is oil-based, it cannot be handled in areas where fire is present.

2. Water-Based Rust Converters

Because water-based products are easy to penetrate, they can soak in and reach areas that are difficult to reach with oil-based products. It is easy to apply on uneven surfaces.

It forms a film in a short time and dries relatively quickly. It has little odor and does not require special care with fire.

How to Select Rust Converters

Rust converters have a strong odor and require ventilation. There is also a high risk of ignition, so apply with care. There are two types of rust-converting agents depending on the form of application: brush/roller application type and spray type.

The brush/roller type is suitable when applied to large areas such as fences and gates, while the spray type is easier to use in hard-to-reach areas such as narrow or intricate places. In addition, there are various other types of products, such as those that contain rust-inhibiting ingredients and those that cannot be painted over (they will melt if painted over). It is important to choose the rust converters that best suit your application.

What Is a Lacquer?

Lacquers are important paints widely used in industry and everyday life.

It refers to paint made by dissolving a synthetic resin such as acrylic in a volatile solvent called toluene or acetone. Originally, lacquers were made by dissolving nitrocellulose in an organic solvent.

Today, however, it is used as a generic term for quick-drying paints that use volatile solvents. Because it dries very quickly and is easy to handle, it is commonly used in spray cans.

Uses of Lacquers

1. Protection and Decoration of Wood

Lacquers are applied to wood surfaces to improve durability and provide a beautiful finish. They are used on furniture, flooring, and building materials to effectively protect wood and enhance its decorative qualities.

2. Rustproofing and Maintaining the Aesthetic Appearance of Metals

Lacquers, when applied to metal surfaces, serve to prevent oxidation and rusting. They are also used to paint automobiles and bicycles and to decorate metal products because of their beautiful luster and color.

3. Protection and Modification of Plastics

Lacquers also provide a protective layer for plastic products, preventing fading and deterioration. They are also used to modify the surface of plastics to add specific properties.

4. Imparting Color and Design

Lacquers are used for design and artistic purposes because of their versatile colors and sheen. They are applied to furniture, crafts, and artwork to achieve a unique appearance.

5. Aircraft and Ship Painting

Aircraft and ship exteriors require durability and resistance to weather conditions. Lacquers are used as paints that meet these requirements and continue to protect the appearance of ships and aircraft.

6. Industrial Product Finishing

Lacquers are also used in the finishing process of industrial products to ensure their appearance and durability. They are applied to metal parts and machine surfaces to enhance the quality of the product.

7. Improved High-Temperature Resistance

Some lacquer types have high-temperature resistance and are applied to parts and structures that are used in environments subject to heat. This improves safety and durability.

8. Arts and Crafts

Lacquers are also used to finish traditional crafts and artwork. They are applied to works of art and sculptures to beautify and protect them.

Principle of Lacquers

When lacquers are applied in a liquid state, their main component, the solvent, evaporates in the atmosphere. The evaporation of the solvent causes the paint to dry rapidly and change to a solid form.

As the solvent evaporates, the solid components in the paint gradually begin to migrate to the surface. This creates a thin film of paint, and the thickness and uniformity of the film are adjusted according to the properties of the paint.

The film formed on the surface undergoes chemical reactions such as oxidation and polymerization upon reaction with oxygen. This causes the paint film to solidify, forming a uniform, hard film. The properties of the film formed by chemical reactions are determined by the paint’s composition and additives. The properties of the film, such as hardness, gloss, weather resistance, and chemical resistance, vary depending on the type of Lacquers and the application.

Lacquer films also adhere to the substrate surface and are characterized by chemical or physical adhesion. In this way, Lacquers protect the surface of the substrate to which they are applied and provide resistance to external forces.

Types of Lacquers

1. Nitrocellulose Lacquers

Nitrocellulose lacquers are paints based on nitrocellulose. They dry quickly and provide uniform gloss and protection to wood and metal surfaces. Often used on musical instruments and furniture, they form a thin film and provide a beautiful finish.

2. Acrylic Lacquer

Acrylic lacquers are paints based on acrylic resin. They are characterized by high weather resistance and resistance to discoloration of the paint film. They are used for car exteriors, plastic products, furniture, etc., and provide durability and a beautiful finish.

3. Urethane Lacquers

Urethane lacquers are paints that use urethane resin as their main ingredient. They have excellent abrasion and chemical resistance and are widely used on wood, metals, and plastics. They are used for furniture, flooring, automobile interiors, etc., and provide long-term protection by forming a hard film.

4. Enamel Lacquer

Enamel lacquers are paints that combine hard resins and pigments. They are highly durable and are used on metals, ceramics, glass, and other materials. Widely used in models, industrial products, and decorative items, they provide a beautiful finish and protection.

5. Shellac

Shellac is a natural lacquer composed mainly of insect secretions. It serves to protect wood and furniture surfaces, adding luster and depth. It is used for food and pharmaceutical coatings and for finishing musical instruments.

What Is Oil-Based Paint?

Oil-based paints are paints that use organic solvents, such as thinner, and often include dry or non-drying oils instead of synthetic resins. This category also includes acrylic paints used in artwork. They are distinct from water-based paints, where water evaporates during drying, as opposed to the organic solvents in oil-based paints.

Uses of Oil-Based Paints

Oil-based paints are known for their durability and finish quality, making them suitable for roofing, exterior walls, car bodies, ships, and indoor areas requiring high durability like flooring. They are also used on metals and other materials that are not compatible with water-based paints due to their high adhesion and versatility.

Differences Between Oil-Based and Water-Based Paints

Figure 1. Difference between oil-based and water-based paints

Oil-based paints have stronger coating films, better adhesion, durability, and weather resistance than water-based paints, but they also have a stronger odor and are more expensive.

Types of Oil-Based Paints

Figure 2. Comparison of paint properties between different resins

Oil-based paints include four main types of resins: acrylic, urethane, silicone, and fluorine, each offering distinct advantages in terms of color, gloss, durability, and weather resistance.

Other Information on Oil-Based Paints

Classification of Solvents

Figure 3. Classification of paints

Oil-based paints are classified into strong and weak solvent types. Strong solvents dissolve resins more effectively but may damage certain substrates, while weak solvents are less volatile and take longer to dry.

Classification by Usage

Figure 4. Types of strong and weak

What Is Alkyd Coating?

Alkyd Coatings are room-temperature drying paints made primarily from alkyd resins, which are ester compounds of polybasic acids like phthalic anhydride and polyhydric alcohols such as glycerin. These are modified with various oils and fatty acids to enhance paint quality.

Modified Alkyd Coatings include variations with silicone resin, epoxy resin, and styrene monomer, offering improved adhesion, weather resistance, and pigment dispersion. They exhibit good color and gloss retention, and the coating film is highly resistant to water, solvents, and heat.

Applications of Alkyd Coating

Alkyd Coating is widely used for finishing and protective coatings due to its quick-drying, adhesive, impact resistance, and durability properties. It’s utilized in indoor and outdoor coatings, building materials, steel structures, ships, vehicles, and metal coating for large electrical equipment, machine tools, agricultural equipment, and woodworking.

Characteristics of Alkyd Coating

Alkyd Coating contains unsaturated fatty acids like linseed oil, soybean oil, and castor oil. Depending on the fatty acid content, they are categorized as long-oil, medium-oil, or short-oil. Short-oil coatings have high gloss and hardness, while long-oil paints are more workable but less resistant to water and chemicals. Medium-oil variants have intermediate properties.

During drying, alkyd coatings undergo oxidative polymerization, where the dry oil component reacts with air oxygen, forming a tough coating film. This reaction generates heat.

What Is a Drill Press Vise?

A drill press vise is a tool used to secure the workpiece during machining. Also known as a solid vise, it is mounted on the table of a machine tool for machining.

Attached to the drilling machine table, drill press vises secure the workpiece. Clamping the workpiece to the vise aligns it parallel to the drilling table.

The vise has a hollow bottom at the mouth where the workpiece is clamped, preventing damage to the vise after drilling through it with a drill or other tool.

How to Use a Drill Press Vise

Fix the vise to the drilling table using mounting clamps (mounting screws). Initially, only tighten the clamps temporarily to adjust the vise’s parallelism later.

Check the parallelism of the vise with a dial gauge. Adjust if the vise is not parallel.

Once the vise is confirmed to be parallel, fully tighten the temporarily tightened clamps. Place the workpiece in the clamp, ensuring it is parallel to the table. Turning the handle moves the vise’s movable part, securing the workpiece firmly without wobble or lifting.

How to Select a Drill Press Vise

When choosing a drill press vise, consider the width of the mouth and the maximum opening width of the clamping portion. Ensure the vise can be mounted on your machine without exceeding its loading weight. The material and functionality of the vise should suit your working environment and the machine tool.

• Material of the Main Body
  Choose a cast iron (carbon-mixed) vise for operations like cutting and drilling, as it resists abrasion and absorbs vibration. Ductile cast iron offers high impact and tension resistance, plus elasticity, for strong clamping force.
• Functionality
  A vise with a precision-finished bottom surface ensures greater parallelism with the drilling machine when mounted, reducing rattling or tilting on the drilling table.

What Is a Plier Wrench?

A plier wrench is a versatile tool designed for gripping and tightening bolts and nuts. It is similar to water pump pliers, which are primarily used for plumbing maintenance but offers easier adjustability in the opening width compared to a monkey wrench. Unlike standard wrenches, plier wrenches apply force on two surfaces, reducing the likelihood of damaging the corners of bolts or nuts due to their firm grip.

Uses of Plier Wrenches

Plier wrenches combine the gripping capability of pliers with the tightening functionality of monkey wrenches and standard wrenches. They feature an adjustable opening width like monkey wrenches, but their flat gripping surfaces allow for secure tightening of bolts and nuts without corner damage.

How to Select a Plier Wrench

When choosing a plier wrench, consider the following:

Grip Type

• Plastic Grips: Common and thin, suitable for detailed work due to easy fingertip handling.
• Comfort Grips: Made of two materials, usually red and blue, offering a softer touch for extended use. They are generally heavier than plastic grips.

Aperture Width

The aperture width of plier wrenches varies. A wider aperture can accommodate various nut sizes. While less expensive models tend to have narrower openings, a wide aperture is not always necessary for general use. However, for diverse applications like factory work, a plier wrench with a broader aperture is recommended.

What Is a Bit Holder?

A bit holder is a tool designed to securely hold and organize screwdriver bits. It is used for storing and carrying multiple bits, preventing them from getting lost. Some bit holders also function as screwdrivers, allowing bits to be inserted and used directly for screw driving.

Commonly, bit holders are made of resin with numerous cylindrical compartments for individual bits. There are also metal bit holders designed for individual separation and easy carrying, often attached to a carabiner hook.

How to Use Bit Holders

Bit holders can be used in two main ways:

• Storage Tool: Bit holders store bits by inserting them into designated compartments. They are particularly useful for carrying various types of bits simultaneously. Some models incorporate magnets for a more secure hold.
• As a Screwdriving Tool: Certain bit holders are designed to function as screwdrivers, allowing users to leave the bit inserted and use the holder like a screwdriver.

How to Choose a Bit Holder

There are mainly two types of bit holders: case type and individual type.

• Case Type: This type usually consists of a resin case with horizontally aligned cylindrical holes for bit storage. The benefits include easy insertion and removal of bits and affordability due to simple construction. However, they can be bulky due to side-by-side storage and may not offer strong bit retention.
• Individual Type: Individual bit holders can be collectively carried by attaching their rings onto a carabiner. This type is secure and effective in preventing loss, and can be used directly as a tool, reducing the number of necessary tools. However, detaching each bit holder from the carabiner can be time-consuming. These holders tend to be more expensive due to their metal construction and complex design.