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Screw Management Methods to Prevent Fastening Failures: Checkpoints in the Manufacturing Site

  • Column
  • May 02nd, 2025
Screw Management Methods to Prevent Fastening Failures: Checkpoints in the Manufacturing Site
Many everyday products are held together by screws. This small component, often overlooked, actually plays a crucial role in maintaining the quality and safety of products. What happens if a screw is not properly tightened? It could lead to reduced performance, malfunction, or even serious accidents. In industries requiring high reliability, improper screw fastening must be absolutely avoided. This article explains the types and causes of screw fastening failures that may occur in manufacturing settings, along with specific management methods and checkpoints to prevent them. We hope this content will support site managers, operators, and quality control personnel in achieving safer and higher-quality manufacturing. To ensure stable quality, it’s important to first understand what types of fastening failures can occur and what causes them. Here are some of the most common screw fastening failures encountered on-site: Loosening: A phenomenon where the screw gradually rotates and the fastening force weakens due to vibration, shock, or temperature changes after tightening. This is especially critical in machines that operate under constant vibration. Breakage: When the applied torque (the force used to turn the screw) is too high, the screw or the material being fastened cannot withstand the force and breaks. On the other hand, insufficient torque can lead to loosening or rattling. Stripping (Damaged Screw Head): This occurs when the tool doesn’t properly engage with the screw head’s slot or corners and still rotates, resulting in the slot or corners being rounded off, making it impossible to turn the screw. This is common with small screws or screws made of soft materials. Misalignment / Angled Fastening: This happens when the screw is not inserted straight or in the correct position before being tightened. This can lead to improper assembly, malfunction, or insufficient strength. In addition to these, other issues such as excessive compression of gaskets or initial defects in the screws themselves can also occur. These fastening defects are often the result of multiple interrelated factors. Let’s look at the main causes: Improper Screw Selection: Choosing screws that do not match the operating environment (temperature, humidity, vibration), required strength, or the type of material being fastened (e.g., incorrect material, strength grade, or type) can easily lead to corrosion, insufficient strength, or loosening. Poor Torque Management: Fastening torque is not properly set or controlled, tools like torque wrenches are not calibrated, or tightening is done by feel. These factors contribute to over-tightening or under-tightening. ...

Types of Special Screws Useful on the Production Line and How to Use Them

  • Column
  • April 24th, 2025
Types of Special Screws Useful on the Production Line and How to Use Them
Special screws, which dictate the efficiency and quality of manufacturing lines, possess unique shapes, materials, and functions that ordinary screws cannot offer, meeting the diverse needs of manufacturing sites. This article provides a detailed explanation of the types, selection criteria, and application examples of special screws. We hope it serves as a guide for engineers and procurement managers in manufacturing sites to select optimal special screws and achieve improved manufacturing line efficiency and quality.   Hex Socket Head Cap Screws: Tightened with an Allen wrench, allowing high torque transmission and suitability for narrow spaces.   Torx Screws: Characterized by a star-shaped recess, offering even higher torque transmission efficiency and slip resistance.   Tapping Screws: Form their own threads, resulting in high work efficiency and applicability to various materials.   Custom-shaped Screws: Designed with special shapes and dimensions, specialized for specific applications.   Shoulder Bolts: Have a stepped shaft, demonstrating high precision in positioning and part fixing.   Anti-Loosening Screws: Prevent loosening due to vibration or impact, ideal for areas requiring high safety.   Tamper-Proof Screws: Require special tools, contributing to theft prevention and security measures.   Low-Profile Screws: Have a thin head, effective for use in limited spaces.   Vacuum Screws: Specialized for use in vacuum environments, used in semiconductor manufacturing equipment, etc.   Plastic Screws: Lightweight and highly insulating, widely used in electronic devices and medical equipment. Each type of special screw, with its unique shape and function, delivers maximum performance in specific applications. For example, in the automotive industry, Torx screws are used in parts requiring high torque, such as engines, while low-profile screws are used in confined spaces like interiors. In the medical equipment field, titanium alloy or plastic screws are often chosen due to the need for biocompatibility and lightweight properties. These screws significantly contribute to improving manufacturing line efficiency, product quality, and cost reduction.   Stainless Steel: Excellent corrosion resistance and rust resistance, ideal for outdoor use, wet environments, and chemical applications.   Titanium Alloys: Lightweight yet high strength, highly valued in aerospace and medical fields.   Aluminum Alloys: Lightweight and easy to process, used in a wide range of fields including electronic devices and automotive parts.   Brass: Excellent electrical conductivity and workability, used in electrical components and decorative items.   Plastic: Lightweight and insulating, suitable for use in specific environments such as electronic devices and medical equipment. The selection of special screw materials ...

Explanation of screw surface treatment: Methods and examples for improving rust prevention and durability

  • Column
  • April 17th, 2025
Explanation of screw surface treatment: Methods and examples for improving rust prevention and durability
Screws are essential components that play an active role in every aspect of our daily lives and various industries. However, even these small screws can rust or wear out depending on the environment in which they are used. This is where “surface treatment” becomes crucial. This article explains why screw surface treatment is important, what types are available, and how to choose the right one. We hope to deepen your knowledge of screw surface treatment and help you create safer and longer-lasting products. There are various types and methods of screw surface treatment. Let’s take a closer look at the representative ones. Plating is a method of forming a thin film of another metal on the surface of a metal.   Electroplating: A method that deposits metal using electrolysis, capable of forming a relatively thin film. Suitable for small parts.   Electroless Plating: A method that deposits metal using chemical reactions without electricity, making it applicable to non-metal materials as well.   Hot-Dip Plating: A method of plating by immersing the part in molten metal, offering excellent cost performance. This method enhances corrosion resistance by coating a steel substrate with zinc.   Features and Applications: Offers good cost performance and is suitable for corrosion protection in outdoor environments. Protects iron through sacrificial corrosion. Widely used in construction and civil engineering fields.   Advantages/Disadvantages: While highly durable, its durability decreases in high-temperature environments. This method forms a thicker zinc layer than regular zinc plating, offering very high corrosion protection performance.   Features and Applications: Prevents the ingress of oxygen and moisture, demonstrating high durability. Suitable for infrastructure facilities and large buildings.   Advantages/Disadvantages: While highly durable, it is not suitable for precision parts. This method enhances corrosion resistance and wear resistance by adding nickel to the zinc layer.   Features and Applications: Exhibits high durability even in environments with salt damage and many chemicals.   Advantages/Disadvantages: While having high corrosion resistance and wear resistance, costs can be higher. An environmentally friendly treatment method that offers excellent corrosion resistance and durability.   Features and Applications: Allows for various color tones and is widely adopted in automotive, construction, and electronic devices. Also complies with the RoHS Directive.   Advantages/Disadvantages: While environmentally friendly, process control is crucial.   Black Oxide Treatment (Parkerizing): A chemical treatment method that forms a ferrous ferric oxide film. Its rust-preventive power is weak, and it is mainly used for ...

How to choose screws that won’t fail: Common problems and countermeasures

  • Column
  • April 10th, 2025
How to choose screws that won’t fail: Common problems and countermeasures
Screws play an active role in our daily lives, from assembling furniture to home appliances, automobiles, and buildings. However, despite their importance, choosing the wrong screw can lead to wobbly furniture, malfunctioning machinery, and in the worst case, serious accidents. This article comprehensively explains everything about screws, from how to choose them, common troubles and their countermeasures, to how to differentiate screw usage in DIY, furniture, and construction. By reading this article, readers will be able to avoid screw selection mistakes and lead a safe and comfortable life. Screws are used in various products around us, and their types and applications are diverse. To choose the appropriate screw, it is important to first understand the basic structure and characteristics of screws. A screw is mainly composed of three parts: the head, the shank, and the thread. The head is the part that is turned with a tool such as a screwdriver, the shank is the body part for fixing the material, and the thread is a spiral groove cut into the shank, which creates resistance when screwed into the material, playing the role of firmly fixing it. Screw sizes are indicated by their diameter (thickness of the shank), length, and pitch (coarseness of the thread). The diameter is expressed in millimeters (mm), and the length refers to the length of the shank excluding the head. Pitch represents the interval between threads, and there are two types: coarse pitch and fine pitch. The material of screws varies depending on the usage environment and application.   Iron: High strength and widely used for general purposes.   Stainless Steel: Rust-resistant and suitable for use around water or outdoors.   Aluminum: Lightweight and easy to process, but inferior in strength to iron.   Brass: Excellent aesthetic appeal, used for decorative purposes and electrical products. Having this basic knowledge will enable you to make appropriate judgments when selecting screws. Screws come in various types depending on their application and the materials they are used with. Choosing the appropriate screw is extremely important for secure fastening and preventing troubles. Wood screws are used to join wood. They have a pointed tip and advance by forming threads in the wood as they are screwed in. They are commonly used in DIY and furniture assembly.   Selection Tips: Choose screws of appropriate length and thickness according to the hardness and thickness of the wood. Thinner screws are suitable ...

What is the screw fastening force required for manufacturing? Basics of torque calculation

  • Column
  • April 03rd, 2025
What is the screw fastening force required for manufacturing? Basics of torque calculation
In the manufacturing industry, screw fastening is an essential process for ensuring product quality, safety, and reliability. Many products in our daily lives—such as automobiles, aircraft, home appliances, and buildings—are securely assembled using screws. Improper fastening can lead to product failure or accidents, potentially causing a serious loss of consumer trust. Screw fastening not only joins parts together but also significantly affects product performance and durability. For instance, if engine components in a car are not properly fastened, it could result in decreased performance or breakdowns. Similarly, improper fastening of structural parts in an aircraft could lead to serious accidents. This article explains the importance of screw fastening in manufacturing, the definition of fastening force, the basics of torque calculation, torque management methods, causes and countermeasures of fastening defects, latest fastening technologies, real-world application examples, and relevant standards. We hope this deepens your understanding and supports your daily operations. Fastening force refers to the clamping force generated between jointed components when a screw or bolt is tightened. This force is crucial for preventing loosening or breakage at the joint, thereby maintaining the product’s reliability. If the fastening force is insufficient, gaps may form at the joint, increasing the risk of loosening or damage due to vibration or impact. In the worst-case scenario, this could lead to system failure or accidents. On the other hand, excessive fastening force can deform or damage screws, bolts, or even the parts being joined—especially when fragile or thin materials are involved. Fastening force is influenced by various factors such as screw material, shape, surface treatment, lubrication condition, and tightening torque. For example, a higher coefficient of friction reduces fastening force for the same torque. The ideal fastening force also differs depending on the screw material. Understanding these variables and choosing the correct fastening method is critical to achieving appropriate fastening force. Properly managing fastening force improves product quality, ensures safety, and maintains long-term reliability. Appropriate fastening maximizes product performance and minimizes the risk of failures and accidents. Regular maintenance and inspections help preserve fastening conditions and extend the product’s lifespan. Torque and fastening force are closely related, making torque management essential. Torque is the rotational force around an axis and is what we apply when tightening a screw. Although fastening force is difficult to measure directly, it can be indirectly controlled by measuring torque. The basic formula for torque calculation is as follows: T = ...

Stainless steel, steel, and aluminum: How to choose screw materials according to their applications

  • Column
  • March 27th, 2025
Stainless steel, steel, and aluminum: How to choose screw materials according to their applications
Screws are essential components used to fasten objects in both our daily lives and industrial settings. They come in a wide variety, and selecting the optimal material according to the intended application significantly impacts product quality and durability. Among them, stainless steel, steel, and aluminum are the most commonly used screw materials. Each has unique properties and must be selected appropriately depending on the usage environment and purpose. In this article, we will explain in detail the characteristics, applications, and selection points of these screw materials. Choosing the right screw material requires careful consideration of the usage environment and purpose. Below is an overview of three typical screw materials—stainless steel, steel, and aluminum—and their basic characteristics. Stainless steel screws are known for their excellent corrosion resistance, making them ideal for use in humid or outdoor environments. They also offer good strength and heat resistance, allowing them to be used in a wide range of applications. Steel screws are valued for their high strength and cost performance. They are widely used in construction and machinery where strength is essential. However, they are prone to rust, so surface treatments may be required depending on the environment. Aluminum screws are lightweight and corrosion-resistant, making them suitable for fields where weight reduction is important, such as in aerospace and electronic devices. Although they are not as strong as steel or stainless steel, they are highly recyclable. Property Stainless Steel Screws Steel Screws Aluminum Screws Strength High tensile strength and excellent durability. Types like SUS410 offer particularly high hardness. Non-alloy steel has moderate strength, while carbon steel and alloy steel offer very high strength. Lightweight but weaker than steel or stainless. Use aluminum alloys when higher strength is needed. Corrosion Resistance Outstanding corrosion resistance. SUS304 and SUS316 are highly rust-resistant, suitable for marine and chemical environments. Low corrosion resistance, but can be improved with zinc or chrome plating. High corrosion resistance; can be further enhanced with anodizing. Heat Resistance Excellent performance in high temperatures. SUS310S is especially heat-resistant and used in boilers and furnaces. Moderate heat resistance. Special alloy steels are needed for high-temperature environments. Low heat resistance, but some aluminum alloys can offer better performance. Weight Moderate. Lighter than steel but heavier than aluminum. Heaviest among the three. Extremely lightweight (about 1/3 the weight of steel). Workability Good workability, though it may gall under certain conditions. Good machinability. Higher carbon content increases hardness but ...

Complete guide to screw types and applications: Essential Knowledge for the Manufacturing Industry

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  • March 13th, 2025
Complete guide to screw types and applications: Essential Knowledge for the Manufacturing Industry
Screws are essential components found in virtually all products around us. They are widely used in construction, machinery, electronics, automobiles, furniture, and many other fields. Selecting the right screw directly affects the quality and safety of the product. However, because there are so many types of screws—each with specific uses and characteristics—choosing the appropriate one is not always easy. This article provides a comprehensive explanation of screw basics, types, materials, surface treatments, and applications. It also covers specialized screws and the latest technologies, offering knowledge that helps those in the manufacturing field make better decisions in selecting and utilizing screws. We hope that a deeper understanding of screws will lead to improved product design and quality control. A screw is a type of tool used to fasten objects together. By applying rotational force, it generates axial force to hold parts firmly. Most screws have spiral grooves on their outer surface known as threads, which create the fastening force. Screws are used extensively in fields such as construction, automobiles, machining, electronics, and furniture. The basic functions of screws include: Fastening: Securing multiple components together while allowing for disassembly and reassembly. Positioning: Maintaining the correct alignment between components. Power Transmission: Efficiently transmitting rotation or torque in mechanical systems. Additionally, unlike adhesives or welding, screws can be reused, making them an excellent fastening method for disassembly and reuse. There are many types of screws, classified by their application, shape, and function. Below are the major types and their characteristics: Bolts are commonly used with nuts and are ideal for situations that require strong fastening. Variants include hex bolts and flange bolts. Tapping screws are driven directly into pre-drilled materials, creating their own threads as they go. They are used for metals and plastics and help improve assembly efficiency. Designed for use with wood, these screws have pointed tips and coarse threads for easy embedding. They are typically tightened manually or with power tools. These are used to fasten parts in machinery and electronics. Some are paired with nuts, while others are threaded directly into tapped holes. Screws tailored for special purposes include: Torx Screws: Star-shaped slots reduce slippage and provide higher fastening strength. Cap Screws: Screws with a hexagonal recess, allowing secure tightening in narrow spaces. Sheet Metal Screws: Designed to be driven directly into thin metal sheets. As evident, there is a wide variety of screws, and proper selection according to purpose ...

Differences between JIS and ISO screw standards- key points to avoid selection mistakes

  • Column
  • March 06th, 2025
Differences between JIS and ISO screw standards- key points to avoid selection mistakes
“Screws? Aren’t they all the same?” That’s what I used to think a few years ago when I first tried DIY. But when I went to buy screws, I was overwhelmed by the sheer variety. In reality, the world of screws is deep, with precise specifications for dimensions and materials defined by standards such as JIS and ISO. This article provides a beginner-friendly explanation of the fundamentals of screws. Screws are used in furniture, home appliances, automobiles, and many other products around us. Without screws, these products would fall apart. Screws are essential components for fastening and assembling, and standards are crucial to maintain the quality and safety of products. Without standards, screw dimensions and strength would vary, leading to issues during assembly or repair. JIS (Japanese Industrial Standards) are standards used in Japan, while ISO (International Organization for Standardization) defines global standards. Although JIS references ISO, it has evolved independently to suit Japan’s industrial and technological landscape. Therefore, there are some differences between JIS and ISO screw standards. JIS (Japanese Industrial Standards) was established to improve the quality and standardization of Japan’s industrial products and to support the development of domestic industries. On the other hand, ISO (International Organization for Standardization) aims to facilitate international trade and promote technological cooperation by establishing common global standards. While JIS is based on ISO, it features unique standards that reflect the specific needs and conditions of Japanese technologies and industries. The main differences between JIS and ISO screw standards can be seen in aspects such as dimensions, thread pitch, material, and strength. For example, screws with the same nominal diameter may have different pitches in JIS and ISO standards. Additionally, JIS includes some screw types that have been uniquely developed in Japan. When it comes to material and strength, JIS standards are often tailored to suit the environmental conditions within Japan, which may differ from those specified by ISO. For example, an M3 screw has a pitch of 0.6mm in JIS and 0.5mm in ISO. These differences in pitch mean they are not interchangeable. JIS also includes screws not found in ISO, such as certain small-sized screws. Using diagrams or comparison tables makes these differences easier to understand. Nominal Diameter JIS Pitch ISO Pitch M3 0.6mm 0.5mm M4 0.75mm 0.7mm M5 0.9mm 0.8mm As shown above, the pitches differ between JIS and ISO. “Huh? This screw doesn’t fit…” This is a common ...

List of Characteristics of “Commonly Used Screws and Bolts”

  • Column
  • March 01st, 2025
List of Characteristics of “Commonly Used Screws and Bolts”
This article summarizes screws and bolts commonly used in general manufacturing sites, organizing their characteristics in an easy-to-understand format. Please use this as a practical reference list for everyone handling screws, including those in the manufacturing and construction industries. If you want to grasp the basics of screws and bolts thoroughly, start by checking the “Basic Knowledge of Screws and Bolts.” It explains essential information such as types of screws and how to read dimensions in a concise manner. Detailed information is available at the following link: URL: https://ohtavn.com/en/about-dealings/basic-knowledge/ Machine screws are widely used to fasten relatively small components such as machinery and electronic devices. They are designed to be screwed into pre-tapped holes and serve as versatile fastening parts in many applications. Main Features: Used mainly for components with pre-tapped holes; commonly used for fixing internal mechanisms or precision parts. Available in various head shapes (round, flat, bind, etc.), selectable based on application or appearance. Ideal for assembling small and lightweight parts such as industrial products and electronic devices. ▼Reference Article URL: https://ohtavn.com/en/media/what-is-machine-screw/ Built-in screws are supplied already attached to components during the product assembly process. They are integrated with housings or parts to prevent falling off or getting lost, contributing to improved manufacturing efficiency and maintenance. Main Features: Supplied in a state where the screw is pre-fixed to the component, contributing to efficient assembly processes. Prevents loss or dropping; widely used in precision equipment requiring safety and reliability. Does not fall off during disassembly or maintenance, making reuse easy. ▼Reference Article URL: https://ohtavn.com/en/media/what-is-built-in-screw/ Micro screws are extremely small screws with a diameter of less than 1mm, used to fasten micro parts in precision instruments and electronic components. They are adopted in fields requiring high processing accuracy and reliability and may require special fastening techniques. Main Features: Ultra-small size with a diameter of 1mm or less, ideal for fastening micro parts. Used in fields that demand high precision, such as watches, cameras, medical devices, and electronics. In some cases, dedicated tools and careful torque control are required for fastening. ▼Reference Article URL: https://ohtavn.com/en/media/what-is-micro-screw/ Drill screws have a drill-like tip that allows them to be driven directly into metal plates without pre-drilling. They are widely used on job sites where reduced work time and increased efficiency are required. Main Features: The drill-shaped tip enables direct fastening without the need for pre-drilled holes. Ideal for fast construction in metal sheets and ...

Three recommended pumps from Japan Oil Pump, a Japanese manufacturer of all types of oil transfer!

  • Column
  • February 20th, 2025
Three recommended pumps from Japan Oil Pump, a Japanese manufacturer of all types of oil transfer!
A must-see for manufacturers and other companies with oil-related equipment! Nippon Oil Pump, a manufacturer of liquid transport products with over 100 years of history, introduces three recommended products that can be obtained and maintained in Vietnam! ◆GCI (NOP FILTER PUMP) A space-saving coolant pump with filtration function This one unit can handle all your supply pumps, cyclone filters, line filters, and clean tanks! We have models available for a variety of capacities, so we will suggest a product that best suits your facility! Manufacturer website here >> (There is a YouTube video) ◆Trochoid/Trochoid® Pump Active in a wide range of fields, from machine tools to ships Trochoid® pumps are pumps that take in oil between external and internal gears and transfer it by rotating the gears. They have low wear, low noise and a long life. They are used in a wide range of fields, including transferring oil for cooling and lubrication in machine tools, transferring fuel in ships, factories and agricultural greenhouses, engine oil changers at gas stations, changing tempura oil in the food industry, and as a pump that transfers lubricating oil to the gears of wind power generation. [Applications] Construction machinery, industrial machinery, machine tools, food machinery, auto equipment, leisure facilities, environmental equipment, printing machines, ships, etc. For more detailed product information, please visit the Nippon Oil Pump website. Manufacturer website: >> ◆HPM/High pressure coolant pump A new high-pressure coolant pump. Please consider introducing this when you need even higher pressure! For more information, please refer to the manufacturer’s special flyer (English version) below. Click here for the product catalogue >> If there is a product you are interested in, please feel free to contact us. We will set up a meeting with a representative from the manufacturer. For inquiries regarding samples or materials, please respond to this email or contact our sales representative! At Ohta Vietnam, we not only provide ready-made products such as screws and bolts, but also support activities in the manufacturing field such as cutting, inspection, assembly, packaging… Our equipment list is here As a “specialized support” for the manufacturing industry in Asia. If you have any related questions, feel free to contact Ohta Vietnam for detailed support! URL: https://ohtavn.com/en/contact/
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