月: 2023年1月

What Is an Air Table?

An air table is a specialized work table that utilizes air pressure for lifting and moving materials. Commonly used in production lines, its design includes numerous pores on the top panel through which air pressure is transmitted, significantly enhancing work efficiency.

This technology is versatile and finds applications in industries that handle heavy items, bookbinding, and distribution. A familiar example of air table technology in everyday life is air hockey tables found in game centers.

Uses of Air Tables

Air tables are primarily used in paper mills, bookbinding plants, and the logistics industry. They are instrumental in handling packaging materials, sorting fruits and vegetables, and sorting lines for industrial waste. Some air tables integrate with standard work tables, and certain models feature adjustable airflow, which is particularly useful in bookbinding operations.

Principle of Air Tables

In agricultural applications like sorting fruits and vegetables, air tables utilize air pressure to sort items based on their specific gravity. They are effective in sorting and removing foreign objects like stones and metal fragments in grain sorting lines for rice and wheat. In recycling and waste management, they facilitate the sorting of plastics, metals like copper and aluminum, and even precious metals like gold from industrial waste. When combined with optical sensors, air tables enable more sophisticated sorting processes.

For simpler operations, air tables improve the efficiency of feeding operations such as in paper handling. By adjusting the air pressure to the weight of the paper, a stream of air is created that can lift and move loads like a 20 kg paper stack with minimal effort.

What Is a Filter Regulator Lubricator?

The FRL unit, comprising a filter, regulator, and lubricator, is crucial in pneumatic systems for processing supply air. These units are particularly vital for the stable operation of pneumatic tools and machinery.

Filters and regulators are indispensable in many pneumatic lines for removing impurities and controlling air pressure, even as the use of lubricators has declined with the advent of oilless pneumatic equipment.

Uses of FRL Units

FRL units play a pivotal role in cleaning and stabilizing air in pneumatic systems, thereby extending the lifespan of pneumatic equipment. The filter, typically upstream, removes contaminants from air compressed by the compressor. The regulator then adjusts this air to the required pressure. Lubricators, which add oil to the air, are less common now but still find use in specific applications.

These units are often installed in the air supply section of pneumatic systems in various industrial settings.

Principle of FRL Units

In an FRL unit, the filter, regulator, and lubricator are connected in sequence, starting from the upstream side of the pneumatic line. This arrangement simplifies connections, requiring only two air tubes — one upstream from the filter and one downstream from the lubricator.

The filter typically removes particles between 5 and 60 micrometers in size. The regulator then balances the fluctuating pressure from the compressor using a pressure-regulating spring. While traditional lubricators are now less common due to grease-filled, lubrication-free cylinders, some systems still use them for specific tasks. Additionally, modern FRL units might include a mist separator to further purify the air, removing particles as small as 0.4 micrometers.

What Is a DIAC?

A DIAC, or diode for alternating current, functions in AC circuits to distribute current in both directions once a specific voltage threshold is exceeded. Also known as a trigger diode, it comprises two parallel-connected diodes facing opposite directions, enabling it to control switching operations effectively in AC power supplies. Its use extends to triggering devices like triacs for applications in lighting dimming and heating control, leveraging its bidirectional current flow for smooth operation. The simplicity of its two-terminal design facilitates less complex circuit configurations, enhancing design efficiency and longevity over mechanical switches.

Applications of DIACs

DIACs serve various roles in electrical systems, including:

Lighting Dimming

They play a crucial role in adjusting lighting brightness, where their triggering action ensures smooth transitions in luminosity.

Heating Control

In heating systems and ovens, DIACs contribute to temperature regulation by controlling the activation of heating elements for consistent heat distribution.

Electric Motor Control

DIACs are instrumental in managing AC electric motors, particularly in adjusting rotation direction and speed, in conjunction with triacs and SCRs for precise current control.

Operating Principle of DIACs

DIACs are characterized by their PNPn semiconductor structure, activating to conduct AC signals beyond a threshold voltage in both positive and negative cycles. This bidirectional capability ensures seamless operation across AC power supply fluctuations, with current flow maintained until the input voltage falls below the threshold.

Selecting DIACs

When choosing a DIAC, consider the following factors.

Breakover Voltage

Select a DIAC with a breakover voltage that matches the application requirements, ensuring it can initiate conduction at the desired voltage level.

Rated Current

The DIAC should support the maximum current demand of the circuit without compromising performance, as indicated by its current rating.

Rise Time

For applications requiring swift switching, the DIAC’s rise time, or the speed at which it enters a conduction state, becomes critical.

Leakage Current

Opt for DIACs with minimal leakage current to enhance efficiency, especially in applications where precision is key.

Package Type

Choose an appropriate package type based on the physical constraints and installation requirements, with common options including DO-35, TO-92, and TO-220.

What Is an Airless Sprayer?

An airless sprayer is a high-pressure painting device that converts liquid material, such as paint or wall finish, into a fine mist without using air. This is achieved by propelling the liquid through a nozzle at high pressure, resulting in a uniform and evenly distributed spray. The flexibility of the nozzle hose makes it ideal for covering complex surfaces, including irregular shapes and uneven textures.

This technology is similar to that used in high-pressure washers and airbrushes.

Uses of Airless Sprayers

Airless sprayers are widely used in various applications, including vehicle and machinery painting, wall base coating, and liquid wall finishing. They can handle most types of paints, from special solvents to water-based varieties. In the arts and crafts sector, airless sprayers are favored for their ability to deliver a smooth, glossy finish on objects, posters, signboards, and craft items. They are particularly effective in replicating traditional brush painting techniques in brand-name handicrafts.

Principle of Airless Sprayers

The key feature of airless sprayers is their ability to maintain high hydraulic pressure (around 20 Mps) over extended periods, ensuring consistent spray quality. Key factors distinguishing different models include their continuous spraying capacity (measured in square meters), compatibility with high-viscosity solvents like resin-based paints (e.g., melamine, acrylic), and portability.

For resin-compatible models, ease of nozzle cleaning and part replacement are crucial. A pressure measuring device ensures that the sprayer maintains optimal pressure during use, allowing for immediate adjustments if the pressure drops. This feature is particularly valuable in interior remodeling and maintenance work in residential complexes, where quiet operation is also a major advantage.

For DIY enthusiasts and hobbyists, simpler airless painting equipment is available, often using a cartridge-type air can for propulsion.

What Is a Chisel?

A chisel is a tool designed for processing hard materials such as metal, rock, concrete, and more. They come in various types, each with differently shaped tips to suit specific purposes. The tip of a chisel is typically wider and sharpened for effective scraping and cutting.

Uses of Chisels

Chisels are used in a range of applications, including cutting thin steel plates, scraping old concrete, and removing metal burrs, and spatter from welding. They are most effective for manual processing of small parts. For tougher materials or thicker boards, chisels are often used in conjunction with a hammer to strike and break the material. They are also used for breaking bricks and blocks in construction and home remodeling projects.

Principle of Chisels

Chisels are typically made of steel, a material stronger than the objects they are designed to process. High-frequency quenching is often used in the manufacturing of chisels to enhance their strength. While chisels are not extremely sharp, caution is still necessary to prevent injury.

Different types of chisels are tailored for specific uses:

• Flat Chisels: Bar-shaped with a wider tip, suitable for general applications.
• Brick Chisels: Feature a spatula-like wide tip, ideal for breaking bricks and stones.
• Cut Chisels: Similar to brick chisels, used for removing blocks and road signs.
• Slot Chisels: Have a flat handle and tip, suitable for sheet metal and burr removal.
• Tester Chisels: Characterized by a thin, pencil-like tip, allowing for precise application of force.

What Is a Pipe Threader?

A pipe threader, often used at construction sites, processes external threads on pipes, facilitating the connection of water and gas pipes. This equipment is crucial for fitting pipes to required lengths and threading them to ensure secure connections, and varies from manual threading dies, suitable for smaller pipes, to powerful machines designed for large-diameter pipes which require significant force for threading.

Uses of Pipe Threaders

Pipe threaders are indispensable at construction sites for connecting pipes such as water, gas, and electric conduit pipes. Cutting threads directly into pipes and securing them with connectors ensures a robust connection, ideal for stable installations. Despite the hardness, corrosion resistance, and cost-effectiveness of stainless steel pipes, their challenging processing requirements make pipe threaders a necessary tool. Available in both manual and electric models, electric pipe threaders are preferred for their speed and convenience, with manual versions serving as backups in areas without power.

These machines are versatile, capable of threading bolts and conduit pipes in addition to gas and water pipes.

Principle of Pipe Threaders

Pipe threaders operate by cutting threads with a die head and chasers. The die head secures the chasers, the blades that form the external thread on the pipe. It ensures the screws are cut to precise sizes, holding four chasers at a 90° angle. Different sized threads can be achieved by swapping out the die head. The chasers, directly contacting the pipe, have a thread shape matching the standard, with multiple blades arranged in concave and convex patterns. Threading is executed by positioning the pipe with the set die head and chasers and rotating it to form the threads.

Types of Pipe Threaders

Electric pipe threaders primarily come in two variants.

Automatic Cut-off Threaders

Automatic pipe threaders allow for setting the desired thread length, automatically stopping the threading process once the set length is achieved. This type is widely used for its efficiency and precision.

Manual Cut-up Threaders

Manual pipe threaders require the operator to manually monitor and control the thread length during processing, offering more control at the cost of increased labor.

Other Information on Pipe Threaders

Thread Roller

Thread rollers, which utilize pressure instead of cutting to form threads, deform the pipe surface plastically. This method preserves the pipe’s wall thickness, resulting in stronger pipe connections compared to the chaser type, albeit at a higher cost.

Precautions for Using Pipe Threaders

Using thread cutting oil is crucial when working with chasers to prevent damage and extend their lifespan. Additionally, the choice of chasers must correspond to the piping material to avoid unnecessary wear, underscoring the importance of a thorough pre-use check of the chasers.

What Is a Pumping Engine?

Pumping engines are driven by internal combustion engines and are designed to move fluids efficiently. These engines enable operation in remote or unstable power supply locations, making them invaluable for rural areas, construction sites, and emergency disaster response. With robust and reliable designs, they excel in challenging environments and can move large volumes of liquid quickly for tasks like drainage and firefighting.

Using the correct fuel and lubricants is crucial for safety and performance. Proper handling minimizes risks of leaks and fires, and it’s essential to implement fire safety measures due to the engine’s heat output.

Uses of Pumping Engines

Pumping engines serve various roles across multiple industries, including:

• Fire Fighting – They provide high-pressure water flow for firefighting, integral to extinguishing forest and vehicle fires.
• Agriculture – Used for irrigation, pesticide and fertilizer application, and drainage, they enhance crop growth and manage water levels in fields.
• Disaster Response – During floods, they play a critical role in water removal and levee reinforcement, and can supply drinking water or support sewage drainage for sanitation post-disaster.

Principle of Pumping Engines

Pumping engines combine an internal combustion engine with a pump to move liquids. These engines, which can be gasoline or diesel-powered, convert fuel energy into mechanical motion to drive the pump. The pump’s components, including the impeller, create suction and pressure to efficiently move liquids through the system.

Types of Pumping Engines

Pumping engines are categorized by their internal combustion engine type.

2-Cycle Engine Pump

These are lightweight, compact, and relatively simple to maintain, suitable for portable applications and light-duty tasks. They have a simple two-stroke operation cycle, but may have lower fuel efficiency.

4-Cycle Engine Pump

Four-stroke engine pumps offer high efficiency and lower emissions, making them ideal for industrial use and demanding applications. They feature a more complex design with distinct operational phases, requiring regular maintenance.

What Is an Embossing Punch?

An embossing punch is a tool used to create a raised relief surface on pliable materials like metal, paper, or fabric. This process, known as embossing, can create various patterns, from simple letters and numbers, circles, and squares to complex geometric designs.

Embossing not only enhances the aesthetic appeal of items like books and credit cards but also serves practical purposes, such as reducing surface friction or creating a matte finish on materials.

Uses of Embossing Punches

Embossing punches have diverse applications, broadly categorized into aesthetic enhancement and functional improvement. Aesthetically, embossing is utilized in the design of credit card numbers or vehicle license plates, where raised characters are preferred. Functionally, it’s applied in products like toilet paper to create a textured surface.

Principle of Embossing Punches

Embossing involves creating a raised pattern on one side of a material, while debossing creates an indented pattern on the opposite side. Both processes are fundamentally similar, differing only in the direction of the relief.

An embossing punch consists of two matching plates with the desired pattern. When material is placed between these plates and pressure is applied, the pattern is imprinted onto the material, creating a raised effect.

Embossing is effective only on malleable materials. For instance, embossing wood may lead to cracking due to its rigidity, while plastics may require higher temperatures to be pliable enough for embossing. The thickness of the material, especially in the case of paper and metal, is also a crucial factor for successful embossing.

What Is a Sander?

A sander is a power tool that uses a motor to sand surfaces through a rotating motion. Most sanders operate with an eccentric rotation, meaning the center of rotation is offset, allowing for more effective and wider area polishing.

Using a sander often generates dust, and many models come equipped with a dust collection bag for convenience.

Uses of Sanders

Sanders are widely used in construction, production, and increasingly in DIY projects. Their primary use is to smooth the surfaces of various materials. They are particularly effective for:

• Removing burrs from cut wood
• Eliminating rust from metal surfaces
• Cleaning deteriorated paint from surfaces
• Chamfering metal materials

For extensive surface treatment or small areas, sandpaper may be used, but sanders provide a more uniform finish.

Principle of Sanders

There are two main types of sanders: those using circular abrasive discs for grinding, and orbital sanders that use sandpaper or cloth files. Orbital sanders, with their elliptical sanding motion, are particularly suited for flat surfaces. Worn-out sandpaper can be easily replaced, and these sanders can be adapted for a range of tasks including glazing and waxing wood surfaces.

How to Choose Sanders

The market offers various types of electric sanders, each suited for specific tasks. Orbital sanders are versatile but less abrasive, while random orbital sanders offer higher efficiency but at a higher cost. When choosing a sander, consider the intended use, the need for dust collection, and the compatibility of sanding paper.

Additional Information on Sanders

1. How to Use Sanders

Proper use of sanders is crucial for safety and effectiveness:

1. Cut the sandpaper to fit the sander’s pad size.
2. Secure the sandpaper under the pad with the lever lock.
3. Ensure the sandpaper is taut and without slack.
4. For flat surfaces, keep the entire pad in contact and move the sander back and forth.

Always wear protective gear such as work gloves and safety goggles to prevent injury.

Origin of the Name “Sanders”

The term “sanders” likely originates from its function in sanding or polishing surfaces. However, the exact origin is uncertain. Sanders are sometimes interchangeably referred to as “grinders,” especially when disc grinders are involved.

What Is an Electric Welder?

An electric welder is a tool that employs arc discharge to fuse metals together. This category includes DC inverter welders and AC arc welders. Notably, some electric welders are battery-powered, offering portability for use in areas without a power source.

Electric welders designed for standard 100 V household use are also available. Unlike processes that use flammable gases, such as acetylene, electric welders do not require special qualifications, simplifying their use.

Uses of Electric Welders

While welding machines are commonly found in metalworking factories, they are less frequent in everyday settings. However, they are invaluable for projects involving metal, such as shelf construction or crafting small metal items.

Without a welder, metal parts must be connected using screws and nuts. This method is feasible for simple shapes like pipes and plates, but more complex configurations often necessitate welding.

Principle of Electric Welders

Electric welders function by melting welding rods through arc discharges, producing temperatures high enough to liquefy metal. The molten electrode material serves as a binder, creating a robust metallic bond between the metal parts.

Typically, electric welders can join various ferrous materials, including soft iron, stainless steel, and cast iron. It is important to note that arc discharges emit intense light and harmful ultraviolet rays, necessitating eye protection during use to prevent damage.

Moreover, as electric welders involve an electric circuit, grounding the welding object is essential to avoid electric shocks.

Semi-automatic Welding Machines

Semi-automatic welders join materials by melting metal automatically supplied to a heating device or torch. These machines are categorized into gas-shielded arc welding and non-gas welding methods.

Gas-shielded arc welding involves using inert gas to protect the hot metal from oxidation. There are three types based on the shielding gas used: CO2 welding, MAG welding, and MIG welding.

CO2 welding, employing solely carbon dioxide gas, is prevalent for steel welding. MAG welding uses a mix of gases, typically 80% argon and 20% CO2, suitable for iron and stainless steel welding. MIG welding, ideal for stainless steel and aluminum, utilizes argon or an argon-oxygen mix, resulting in a clean finish but at higher operational costs.

Qualifications for Electric Welders

Using electric welders carries risks like electric shock, explosions, and fires. To mitigate these risks, specific training for electric welding workers is mandated, along with adherence to local standards and regulations. Such training covers arc welding techniques and relevant legal provisions.