月: 2023年1月

What Is Stainless Steel Machining?

Stainless steel machining involves machine processing of stainless steel, a material chosen for its corrosion and heat resistance. Despite its high hardness, which traditionally made it difficult to work with, advancements in machining processes have improved the ability to effectively machine stainless steel.

The challenges of machining stainless steel have been addressed through a better understanding of the material’s properties, selection of suitable machining processes, and advancements in the various materials and machining equipment.

Uses of Stainless Steel Machining

Stainless steel machining is used in various fields due to the material’s superiority. It is used in products ranging from tableware and home appliances to construction materials and elevator interiors. The continual improvements in machining technology are expected to further expand its applications.

Types of Stainless Steel Machining

Various stainless steel machining methods have been developed to fully utilize the material’s characteristics. These methods are similar to those used in conventional metalworking but require innovations to accommodate the unique aspects of stainless steel. For instance, advanced technologies like laser processing are introduced for cutting, where the material’s hardness previously hindered workability.

Advanced IT technology is also employed to predict and control springback in stainless steel machining. In welding, TIG welding is effective for thin sheets, but thicker sheets rely on the skill of technicians. Cutting stainless steel requires careful consideration of work hardening and distortion, depending heavily on the machinist’s expertise.

Various stainless steel surface treatment methods are employed, such as pickling, which removes impurities and enhances corrosion resistance, and black oxide processing which uses alkaline chemicals.

What Is a Metalworking Service?

Metalworking encompasses the processing of metal materials, including operations such as cutting, milling, and bending using various tools and machines. Another form of metalworking is casting, where nonferrous metal is poured into a mold, known as die casting, to achieve a specific shape.

Beyond these, metalworking also involves heat treatments like quenching, tempering, and annealing, as well as surface treatments such as plating. This field is distinct from other material processing types, such as stonework and woodworking.

Uses of Metalworking Services

Metal processing techniques vary depending on the material’s form. For example, metal sheets require cutting to size and bending with a press. Round bars of metal are shortened to the desired length on a lathe, then shaped through cutting processes, and threading may be added as needed. These semi-finished products, once shaped and bent, undergo surface treatments like heat treatment and plating before becoming finished products.

Principle of Metalworking Services

Metalworking operates on various scales, from large-scale projects such as bridges and ship fabrication to small-scale creations like jewelry. Each segment utilizes unique tools, skills, and processes. In modern automotive plants, rolled steel sheets are shaped under immense pressure by giant press machines in automated lines, while welding robots assemble automobile body parts. Conversely, in laboratories, precise metal parts are crafted by researchers using computerized, numerically controlled machine tools to cut aluminum blocks, automatically changing cutting bits as needed.

Types of Metalworking Services

Metalworking is categorized into forming and property alteration. Forming methods include machining, plastic forming, casting, and others like welding, powder metallurgy, and metal 3D printing. Property alteration processes primarily involve heat treatment and surface treatment. Machining covers cutting (turning and milling), grinding, and special techniques (e.g., electrical discharge machining, laser machining).

Plastic forming methods comprise stamping, forging (both free and die forging), and rolling. Casting methods include sand casting and die casting, while heat treatments encompass quenching, tempering, normalizing, annealing, and carburizing. Surface treatments typically involve plating and conversion coatings, such as phosphate and chromate treatments.

How to Choose Metalworking Services

Selecting the appropriate metal fabrication method can significantly impact the cost and time required to produce parts with specific dimensions and characteristics. Understanding the advantages and limitations of each method is crucial. For instance, casting allows for rapid, mass production but may vary in dimensional accuracy. Conversely, pressing and cutting maintain high dimensional accuracy. The choice of process should consider the production schedule and delivery timelines. Material costs also influence overall expenses; materials widely available can reduce per-unit costs. However, choosing unsuitable materials for the product design might increase labor costs and production time. Although 3D printing offers efficiency, its initial costs are high.

Structure of Metalworking Services

Machine tools play a vital role in efficiently processing hard materials like metals. Primarily used in material removal processes, these tools include milling machines, drilling machines, and lathes. Machine tools not only produce parts for various equipment and machinery but also enable machining at speeds and precision levels challenging to achieve manually.

What Is an Honing Service?

Honing is a process in which a grinding wheel is pressed against and rotated on the internal surface of a cylindrical part, with a significant amount of cutting oil applied. This method is similar to internal grinding, which also utilizes a grinding wheel to finish the internal surface of a workpiece.

However, honing allows for a larger contact area between the grinding wheel and the workpiece’s internal surface, achieving higher precision in terms of cylindricity, roundness, and surface roughness. As a result, honing is especially suitable for machining parts requiring high precision, such as automobile engine cylinders.

Uses of Honing Services

The inner surface of a honed workpiece features a fine mesh of stripes known as a “crosshatch.” These crosshatches function as lubrication grooves in engine cylinders, forming oil pools that reduce piston wear and resistance, thereby preventing seizure. Consequently, honing is frequently employed for parts involved in piston movement and is also used in machining gear tooth surfaces. The application of honing extends beyond the automotive industry, encompassing agricultural machinery parts, medical instrument parts, and various other fields.

Principle of Honing Services

Honing efficiently finishes the inside of holes. A magnet attached to the honing head secures it against the interior of the workpiece, and the surface is finished with a reciprocating, rotating motion. Honing achieves greater precision in drilling holes than internal polishing, maintaining the hole’s location while polishing, in contrast to internal polishing, which may shift depending on the centering method.

Types of Honing Services

Honing is performed using honing machines, which vary widely in shape, angle, orientation, and machining method. Besides general honing machines, there are three types of specialized honing machines: CNC multi-axis honing machines, parallel plane honing grinding machines, and liquid honing machines. These machines can hone internal surfaces as well as flat surfaces, external surfaces, and gears.

1. General Honing Machine

Uses radially mounted grinding wheels, called “horns,” rotating and moving reciprocally up and down along the axial direction to finish internal surfaces.

2. CNC Multi-Axis Honing Machine

Controls the position and speed via computer numerical control (CNC). Unlike in general honing processes where grinding wheels must be replaced at each stage from rough to final finishing, the CNC multi-axis honing machine automates the entire process.

3. Parallel Surface Honing Grinder

Enables specialized processing of flat surfaces. Two disk-shaped grinding wheels rotate back and forth for machining, allowing simultaneous processing of different shapes and multiple parts to the same height.

4. Liquid Honing Machine

Mixes abrasive grains with water to spray for processing. Suitable for matting, deburring, rust removal, and preparing painted surfaces for finishing. It can also handle complex shapes.

How to Select Honing Services

Honing is a high-precision method for finishing internal surfaces, utilizing a slow grinding process without significant pressure, making it suitable for heat-sensitive materials. The resulting cross-hatch pattern, achieved by controlling the grinding wheel’s rotation and vertical motion, can vary the cross-hatch angle from 20 to 60 degrees. However, honing cannot adjust to different hole diameters; the mandrel size is determined by the workpiece’s inner diameter. Pre-processing accuracy significantly impacts honing outcomes; if pre-processing is imprecise, internal grinding may be preferable, as honing cannot correct such inaccuracies.

What Is a Wire Electrical Discharge Machining (EDM) Service?

Wire Electrical Discharge Machining (EDM) Service is a process where an electric current is passed through a very thin wire, which is then discharged to shape the surface of the metal being processed. This technique operates similarly to a saw, but with high precision.

EDM Service can process any conductive material, regardless of its hardness. Commonly used materials include iron, stainless steel, copper, aluminum, and brass. The wires used in EDM are extremely thin, ranging from 0.02 mm to 0.3 mm in diameter, enabling intricate and precise shaping that is challenging with conventional machining methods.

Uses of EDM Services

EDM Services are ideal for processing any shape of conductive materials with high precision. This method is especially useful in creating fine gears and ultra-precision press dies, where machining of diameters less than 0.05 mm is required. Unlike traditional machining which requires multiple steps, EDM Services can achieve complex and precise processing using only wires based on a programmed design.

Flow of EDM Services

EDM Services are conducted using a wire EDM machine that cuts the workpiece through an electrical discharge phenomenon between the workpiece and a continuously running ultra-fine wire electrode. The process involves:

1. Setting the workpiece on the machine’s table and threading the wire through the starting hole.
2. Initiating spark EDM Service when the wire, insulated in a pure water-filled tank, approaches the workpiece to within a few tens of microns.
3. Generating high temperatures through pulsed current flow, melting the workpiece.
4. Removing the melted metal through a steam explosion of pure water.
5. Cooling the workpiece with water.
6. Repeating the process hundreds of thousands of times per second to cut the workpiece.
7. Moving the table (or wire) to cut according to pre-entered data, with the final product being separated from the workpiece when the machine returns to the starting point.

EDM Services are versatile and capable of processing various conductive materials and complex shapes. Unlike traditional cutting where the cutting edge wears down and must be harder than the workpiece, EDM uses relatively inexpensive materials like brass and tungsten. Since there is no direct contact with the workpiece, costs are reduced. However, EDM Services are less suited for mass production due to the slow processing speed from the heat generated during discharge.

What Is a Silicone Washer?

A silicone washer, a part inserted between a screw or bolt and its seat when tightening, stabilizes the seat and prevents loosening. It is made from various resins such as PTFE, PEEK, and PPS, differing from metal washers which can rust and are not insulated.

Silicone washers are resistant to rust and provide insulation against corrosion. However, their properties, such as resistance to deterioration, cracking, and high temperatures, vary depending on the resin type.

Types of Silicone Washers

There are different types of silicone washers, including flat washers that are even on both sides and spring washers that are uneven. Specialized washers like rosette washers for countersunk screws and thrust washers suitable for rotating parts like bearings are also available. Each type has a specific shape and orientation for screw fitting.

Materials

Silicone washers are made from various materials, including PET (polyethylene terephthalate), PC (polycarbonate), PE (polyethylene), PP (polypropylene), nylon, fiber, and POM (Duracon). Their chemical structures and physical properties vary; for instance, PTFE is chemically resistant and durable, while PPS can withstand temperatures up to 200 °C.

Choosing the appropriate material for the silicone washer is crucial, depending on the environment in which it will be used.

Use of Silicone Washers

Silicone washers function like metal washers in preventing loosening, protecting base materials, and preventing sinking and fall-off. They are typically used between the seat and the base metal. Some resin washers can also act as elastic washers when placed between metal washers.

These washers are used in automobiles, construction, home appliances, industrial machinery, and DIY projects. They also find applications in civil engineering for earthquake resistance and ground subsidence countermeasures. In chemical plants, resin washers with high chemical resistance are preferred due to the use of corrosive chemicals.

What Is a Flux Meter?

A flux meter is an instrument that measures the magnetic flux passing through and changing within a coil. It’s different from a magnetometer, which is a general term for devices measuring the magnetization of materials, and the strength and direction of magnetic fields.

Flux meters can measure even minute magnetic forces, especially when the number of coils is increased. A more sensitive type is the SQUID flux meter, using superconductors. SQUID magnetometers include a Josephson junction in a superconducting ring and measure magnetic flux based on changes in tunnel current at extremely low temperatures.

Principle of Flux Meters

Flux meters measure the amount of magnetic flux through a coil and its changes. They are often used alongside gauss meters, which measure magnetic flux density. When magnetic flux through the coil changes, an electromotive force is generated in the coil.

Magnetometers, like vibrating sample magnetometers, vibrate a sample in a DC magnetic field to measure the magnetic moment of the sample based on changes in the magnetic force and electromotive force in the attached coil.

Flux Meters and Search Coils

Search coils are crucial in flux meters for detecting magnetic fields. Flux meters display the measurement as the product of coil turns and magnetic flux, enabling the measurement of minute forces or small samples by increasing coil turns. The accuracy of the coil winding is essential for sensor performance.

Principle of SQUID Flux Meters

The SQUID flux meter, or “Superconducting Quantum Interference Device,” is a highly sensitive detector for small magnetic flux changes. It consists of one or two Josephson junctions in a superconducting ring. When cooled to cryogenic temperatures, the tunneling current through these junctions changes, making SQUID flux meters highly sensitive.

Medical Applications

SQUID flux meters have wide-ranging R&D applications, from new material magnetic properties to superconductor research and trace impurity studies. In medicine, they are used to measure biomagnetic fields, like detecting weak magnetic fields from neural activity in the brain or heart. However, the minute magnetism from the heart requires a magnetic shield room during measurement to reduce external magnetic noise.

What Is Predictive Maintenance?

Predictive maintenance involves continuously monitoring and measuring the condition of equipment to detect early signs of deterioration, thereby facilitating timely replacement or repair of parts before failure occurs.

While similar to preventive maintenance, predictive maintenance differs in that it focuses on detecting deterioration early and performing maintenance only when necessary, reducing the likelihood of incurring extra costs associated with regular, scheduled replacements typical of preventive maintenance.

Given the retirement of skilled workers and the need for cost reduction, the manufacturing industry is increasingly adopting digital transformation (DX). Predictive maintenance, which identifies issues early, is being introduced alongside AI and machine learning systems, enhancing maintenance not just for individual parts but for entire facilities.

Difference Between Predictive Maintenance and Preventive Maintenance

Predictive maintenance entails continuous monitoring and measurement of equipment conditions to anticipate and address deterioration before failures or abnormalities occur. In contrast, preventive maintenance involves predetermined replacement frequencies for parts, leading to periodic replacements regardless of actual wear and tear. Predictive maintenance, however, relies on condition monitoring to perform maintenance as needed when deterioration is detected.

Implementing predictive maintenance requires a system for continuous measurement and monitoring, which can be costly and time-consuming to establish. However, it can reduce the costs associated with regular part replacements. Preventive maintenance, while incurring costs for replacing parts that may still be functional, is simpler to implement due to its defined replacement schedule.

Predictive Maintenance, Machine Learning, and AI

Predictive maintenance is defined by its continuous measurement and monitoring approach, with recent advancements in machine learning and AI being employed to determine what conditions signify deterioration. These technologies enable computers to learn from extensive historical data, distinguishing between ‘normal’ and ‘deteriorated’ conditions. With AI learning these patterns, future measurements can be accurately classified as normal or abnormal.

Examples of Predictive Maintenance

Amidst the retirement of experienced workers, increasing equipment complexity, and the need for cost-effective maintenance, the manufacturing industry is shifting from preventive to predictive maintenance through digital transformation (DX). Below, we introduce some specific examples of predictive maintenance.

Predictive Maintenance Using Vibration Sensors

One predictive maintenance method involves installing vibration sensors on factory equipment. By attaching sensors to bearings, motors, pumps, and other components, abnormal vibrations indicating deterioration can be detected. There are also explosion-proof vibration sensors for chemical plants and compatible sensors for food and beverage production lines.

Predictive Maintenance of Machinery and Equipment

Rather than focusing on individual equipment, entire production facilities are increasingly adopting predictive maintenance systems. These systems centralize and visualize measurement data from various equipment, making it easier to analyze. Some systems can learn from past data, failures, and anomalies, detecting issues previously only identifiable through skilled workers’ intuition and experience.

What Is an Industrial Furnace?

An industrial furnace is used to heat ores and other materials at very high temperatures, generally above 400 °C. A typical industrial furnace is a blast furnace, which is used in the smelting process to extract metals from ores.

The specifications of industrial furnaces vary depending on the application, the fuel used, and the method of starting combustion. Also, each company installs industrial furnaces of the appropriate material, shape, and volume according to the production line and production volume. It is especially important to select a furnace with sufficient heat resistance at the operating temperature to prevent deterioration of the insulation and walls of the industrial furnace.

Types of Industrial Furnaces

Industrial furnaces are used in a wide variety of applications and processes, depending on the industry and the product to be manufactured. Generally, they are operated at 400 °C or higher, but they can be customized depending on the process, and some are used at temperatures in the range of 100 °C or lower.

The most commonly used types of industrial furnaces are blast furnaces, converter furnaces, combustion furnaces, resistance furnaces, and induction furnaces. They can also be classified by fuel type, such as gas, liquid fuel, and electricity.

Blast furnaces, the most commonly used type, are cylindrical furnaces used in the smelting process to extract metals from ores. Ores, fuels, and limestone filled to the top of the furnace are heated and react as they move inside the cylinder to produce molten metals and slag. Blast furnaces are designed to operate continuously for 10 years or more, and once they are shut down, a large amount of cost and time are required to restart operations.

What Is Molybdenum Oxide?

Molybdenum oxide represents a class of transition metal oxides with different oxidation states, including molybdenum(IV) oxide, molybdenum(V) oxide, and molybdenum(VI) oxide, also known as molybdenum dioxide, molybdenum pentoxide, and molybdenum trioxide, respectively. Molybdenum trioxide is the most commonly produced form among these compounds.

Uses of Molybdenum Oxides

Molybdenum Oxide (VI)

Used in producing molybdenum metal, as an additive in alloys to enhance hardness and resistance to heat and corrosion, and in various applications including as a corrosion inhibitor, pesticide, ceramic glaze, chemical reagent, and oxidation catalyst.

Molybdenum Oxide (IV)

Applied as a lubricant, in surface treatment, and potentially in lithium-ion batteries due to its good electrical conductivity.

Properties of Molybdenum Oxides

Molybdenum Oxide (VI)

Characterized by its orthorhombic crystal structure, molybdenum oxide (VI) appears as a white to yellow or bright blue crystalline powder. It has a melting point of 795°C, a boiling point of 1,155°C, and is slightly soluble in water.

Molybdenum Oxide (IV)

This brownish-purple crystal, with a monoclinic and distorted rutile-type structure, melts at 1,100°C and showcases notable electrical conductivity.

Other Information on Molybdenum Oxides

Production Process

Molybdenum(VI) oxide can be industrially obtained by roasting molybdenum disulfide, while molybdenum(IV) oxide is produced by reducing molybdenum(VI) oxide at high temperatures in the presence of molybdenum metal.

Legal Information

Both oxides are regulated under various safety and environmental laws for their hazardous and toxic properties.

Handling and Storage Precautions

Due to potential carcinogenic and other health risks, appropriate protective measures should be taken when handling. For storage, molybdenum oxides should be kept in a cool, sun-protected area, and securely sealed.

What Is Ethyl Butyrate?

Ethyl butyrate, also known as ethyl butanoate, is an organic compound with the molecular formula C₆H₁₂O. It is produced through esterification, a dehydration condensation reaction between butyric acid and ethanol, in the presence of sulfuric acid. This clear, colorless liquid is characterized by its diffusion into the air and a sweet, fruity aroma resembling bananas and pineapples.

Uses of Ethyl Butyrate

Primarily used as a flavoring agent in foods and beverages, ethyl butyrate also finds applications in fragrances for soaps and cosmetics, as well as solvents in lacquers, adhesives, and for masking unpleasant odors. Its fruity scent is considered somewhat stronger than that of ethyl acetate, which is often likened to apples.

Properties of Ethyl Butyrate

With a specific formula of C₃H₇COOC₂H₅, ethyl butyrate boasts a molecular weight of 116.16, a density of 0.875 g/mL at 25°C, and a boiling point of 120-121°C. It is highly soluble in organic solvents, such as alcohols and oils, but has very low solubility in water. Notable for its flammability, ethyl butyrate requires careful handling and storage away from fire or heat sources. 

Other Information on Ethyl Butyrate

1. Safety and Toxicity

Found naturally in strawberry juice and apple honey, ethyl butyrate is safe for use in food additives at low concentrations. While not considered dangerous, it may irritate upon direct contact with the skin or respiratory tract if inhaled in vapor form. It is deemed to have minimal environmental hazards.

2. Isomers

Isomers sharing ethyl butyrate’s molecular formula include butyl acetate, pentyl formate, and propyl propionate. These esters are also utilized in fragrances and as solvents.

3. Ethyl Butyrate and Fruit Flavors

Esters of lower or intermediate carboxylic acids and alcohols, like ethyl butyrate, are key to creating a variety of fruit-like aromas. These esters are present in nature and detected in plant oils and fruit juices. The process of esterification transforms the odors of otherwise foul-smelling carboxylic acids (e.g., formic, acetic, butyric, and isovaleric acids) into pleasant fragrances, making for engaging and educational chemical experiments.