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The latest screw technology trends adopted by Vietnamese manufacturing industry

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  • January 16th, 2026
The latest screw technology trends adopted by Vietnamese manufacturing industry
In Vietnam’s manufacturing sector, advancements in electrification, high functionality, and shorter delivery times are raising the standards for corrosion resistance, anti-loosening, and traceability required of screws (fasteners). This article provides a practical overview of the key points of the latest screw technology in Vietnam. It explains surface treatment and hydrogen embrittlement countermeasures, transverse vibration testing (Junker-type), torque and angle management with IoT, thread-forming screws, and preventive measures based on IATF/ISO, complete with implementation procedures and checklists. This is intended for personnel in charge of quality, production engineering, and procurement. The goal is to achieve results verification, standardization, and mass production deployment within 90 days. When mass-producing or procuring screws in Vietnam, it is crucial to distinguish between standards (the language of drawings) and conformity (the language of laws and certifications). This section outlines how to write specifications on drawings, key points for selecting environmentally friendly surface treatments, practical measures to avoid hydrogen embrittlement, and the essentials of local conformity procedures. TCVN (Vietnam Standards) are voluntary, while QCVN (National Technical Regulations) are mandatory. For screw design and manufacturing, descriptions based on ISO/JIS are mainstream from the perspective of international harmonization. Specifying the following three points on drawings can reduce differences in interpretation among suppliers: Size/Grade: e.g., M6×1-8g, Property Class 8.8 (ISO 898-1) Surface Treatment: e.g., Zn-Ni 8-12 µm, finish color, target friction coefficient Test Method: e.g., Friction/axial force correlation ISO 16047, plating requirements ISO 4042 Practical Tip: Use both English and Vietnamese on drawings and purchasing specifications, and operate them as a set with control charts (incoming inspection, plating lot traceability). Audits will check the three-way link of “Standard → Test → Record.” For projects requiring RoHS/ELV compliance, hexavalent chromium-free Zn-Ni and zinc flake (non-electrolytic) are leading candidates. Since electrolytic plating increases the risk of hydrogen embrittlement in high-strength materials, the following controls are essential: Optimization of Pre-treatment: Minimize acid pickling time and concentration to suppress hydrogen absorption. Baking: Perform dehydrogenation treatment after plating, typically at 190 ± 10 °C for 2-4 hours. Hardness Threshold Management: Implement stricter controls for high-strength materials (目安 HV≧320 equivalent). Agreement on Friction Coefficient: Actually measure the friction coefficient μ (ISO 16047) before mass production, depending on the coating agent and film. Specification Example (Excerpt): Surface Treatment: Zn-Ni 10 µm, Trivalent Chromate Finish / Baking: 190 °C × 3 h / Target Friction Coefficient: 0.12-0.18 / Testing: Conforms to ISO 4042, ISO 16047 Non-electrolytic zinc flake ...

What are recyclable screw materials that contribute to a circular economy?

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  • January 09th, 2026
What are recyclable screw materials that contribute to a circular economy?
Achieving carbon neutrality and transitioning to a circular economy begins with the design and operation of individual components. Screws (bolts, nuts, machine screws) are numerous and are typical components that often become “high-mix, low-volume” or “mixed materials” on-site. This article explains how to put “screw recycling” into practice, from material selection to sorting/recovery and standards/certification, assuming implementation at a manufacturing site in Vietnam. This is intended for personnel in purchasing, production engineering, quality assurance, and environment (sustainability) departments. Based on support case studies and standardization templates from  Ohta VIETNAM, we will emphasize the following: Recycling suitability by material (iron, stainless steel, aluminum, brass, titanium, plastic) and the impact of surface treatments Sorting and recovery flow (magnetic/eddy current) and on-site 5S, lot management Use cases for standards and certification: ISO 3506, EN 10204 3.1, ISO 14021/14044 Achieving both cost reduction and CO₂ reduction in Vietnam procurement, and utilizing Ohta Screw Solutions By the time you finish reading, you will have gained practical know-how that you can immediately apply on-site, from preventing the devaluation of scrap due to mixed materials to criteria for reusability and rules for notation in drawings and BOMs. Although small, screws come in large quantities and varieties, making them components that easily become “high-mix, low-volume” or “mixed materials” on-site. To establish a circular design, it is crucial to simultaneously design and standardize four points: ① ease of material recycling, ② ease of sorting based on the presence of surface treatments or inserts, ③ material and lot traceability, and ④ on-site recovery operations (sorting, storage, handover). 30-Second Recovery Flow (Standard Proposal) Clearly specify the material (e.g., A2-70, SUS304, C3604, A5052) and surface treatment in drawings and BOMs. Permanently place material-specific boxes (Iron / Stainless / Brass / Aluminum / Mixed) at the end of the production line. Use magnetic separation followed by eddy current separation (ECS) to sort non-ferrous metals; drain liquids and oils beforehand. Record recovery weight, purity, and handover destination with a lot QR code, and credit the scrap value back to the cost price. Key Points by Material (Summary) Iron/Carbon Steel: Can be quickly sorted in the first stage with magnetic separation. An established recycling route through EAF (Electric Arc Furnace) exists. Plating and oils can be washed off to improve yield. Aluminum: The energy consumed during recycling is low, offering significant CO₂ reduction effects. Can be efficiently sorted with ECS. Stainless Steel (A2/A4, etc.): Markings ...

Latest surface treatment technology that dramatically improves durability

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  • January 05th, 2026
Latest surface treatment technology that dramatically improves durability
In manufacturing sites across Asia, including Vietnam, there is a simultaneous demand for ensuring the corrosion resistance of screws and fastening parts, stabilizing torque, and complying with RoHS/REACH regulations. Rust caused by salt damage or chemical cleaning, and variations in friction coefficients during mass production, can lead to defects and reduced product lifespan. This article compares the latest surface treatment technologies—such as the steam process, zinc-flake coating systems, Zn-Ni plating, electro-galvanizing/hot-dip galvanizing, passivation, and trivalent chromium systems. It also presents selection criteria based on environment and application, along with key points for launching mass production. Surface treatment is a critical process that provides screws and fastening parts with rust prevention, wear resistance, functionality, and aesthetic appeal. The required performance varies greatly depending on the operating environment. Key degradation factors include salt damage in coastal areas, chemical corrosion in chemical plants, UV rays and humidity in long-term outdoor use, and oxidation in high-temperature environments. Selecting the appropriate treatment mitigates these risks, enhancing lifespan and reliability. Furthermore, the tightening torque T is expressed as T ≈ K·F·d, where the stabilization of the friction coefficient dictates the reproducibility of the axial force. Unstable friction increases the risk of improper fastening or damage from over-tightening. Therefore, managing not only the type of treatment but also its friction characteristics is essential. From a standards and regulatory perspective, surface treatment specifications by JIS and ISO, corrosion resistance evaluation tests (e.g., ISO 9227), and environmental regulations like the RoHS Directive and REACH regulations serve as the basis for selection and procurement. Designing specifications based on these factors is directly linked to ensuring legal compliance and competitiveness in the global market. Sources: ISO 4042:2022, ISO 10683:2018, ISO 9227:2017, RoHS Directive 2011/65/EU (Consolidated version 2025-01-01), REACH Regulation (EC) No 1907/2006 This is a new technology that forms a boehmite film on the surface of aluminum alloys by reacting it with water vapor. The film thickness is approximately 3µm, and it demonstrates corrosion resistance comparable to anodizing, even on ADC12 and A7xxx series alloys. The equipment can handle rotary conveyance or bulk processing, and quality control is possible through non-destructive film thickness measurement. As it uses no chemical solutions and has a low wastewater load, it is also suitable for RoHS/REACH compliance. However, design considerations are necessary to prevent uneven reactions on complex shapes or in sealed parts. This water-based coating is free of hexavalent chromium and demonstrates corrosion resistance ...

Next-generation screw technology supporting manufacturing: IoT compatibility possibilities

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  • December 26th, 2025
Next-generation screw technology supporting manufacturing: IoT compatibility possibilities
In addition to the trifecta of demands for high quality, short delivery times, and low costs, manufacturing sites are facing increasingly apparent challenges such as labor shortages and the difficulty of skill succession. Fastening components, though small, are the “final quality gate” that influences equipment operating rates and yield. In recent years, evolution has been accelerating in three main areas: (1) higher-functioning ball screws that elevate machining accuracy, (2) special-shaped screws that reduce workload and errors (3) IoT smart bolts that visualize fastening status. When combined with torque management (the practice of reproducing a specified tightening force) and traceability (history tracking), these technologies form a quality assurance platform that spans from design and procurement to manufacturing and maintenance. This article provides a practical explanation of the key points of each technology, tips for selection and implementation, and an implementation strategy for the Vietnamese manufacturing industry.   NSK’s next-generation ball screws for high-precision machine tools suppress the friction fluctuations that tend to occur when the feed axis reverses its direction of motion, reducing the quadrant glitches that are a problem in machine tools. This stabilizes positioning during contouring corners and at minute pitches, enabling high-quality surface finishing. A practical advantage is that they are designed to be compatible for installation on existing machines, making it easy to achieve phased performance improvements through retrofitting. During motion reversal, the contact state between the balls and the screw groove changes temporarily, and errors are amplified by a combination of friction, backlash, and control system delays. If friction fluctuations can be smoothed out, the compensation load on the control system is reduced, which directly leads to stabilization of contouring accuracy and surface roughness (Ra). Ballbar measurement: Visualize quadrant glitches through deviations in circular motion to quantify the difference before and after retrofitting. Machined surface quality: Evaluate using Ra/Rz values and waviness indicators for mirror finishes and fine groove machining. Energy: Reduced friction lowers the power consumption of the spindle and feed drives, and by suppressing heat generation, thermal displacement is also reduced. Effective for processes requiring µm-order positioning, such as in molds, semiconductors, and medical parts. For existing machines, the effects can be maximized by simultaneously planning for feed screw compatibility and the re-tuning of control parameters (gain/feed-forward compensation).   Accurate’s Totsupra Screw®, with its unique design featuring a 0° bit tip angle, suppresses the upward component of force (bit lift) that occurs during rotation, ...

Screw materials and how to choose for the carbon neutral age | Guide to choosing environmentally friendly screws and CO2 reduction screws

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  • December 19th, 2025
Screw materials and how to choose for the carbon neutral age | Guide to choosing environmentally friendly screws and CO2 reduction screws
Carbon neutrality is a central concept in global efforts to combat climate change and realize a resource-circulating society. In the manufacturing industry, it is necessary not only to save energy and utilize renewable energy in one’s own factories but also to be conscious of reducing CO2 emissions and environmental impact starting from the component material selection stage. Even for small parts like screws, their immense production and usage volumes mean that the choice of materials and manufacturing methods has a direct impact on reducing Scope 3 emissions and on corporate ESG evaluations. This article is for design and procurement managers, quality controllers, and management personnel promoting environmental initiatives in the manufacturing industry. It introduces the types of screw materials suitable for the era of carbon neutrality and how to select them. While incorporating related keywords such as “environmentally friendly screws” and “sustainability parts,” this guide will explain practical points based on the latest technological trends and specific case studies.   Carbon neutrality is the concept of balancing greenhouse gas emissions with absorption to achieve net-zero emissions. It is widely promoted internationally through initiatives like the COP conferences, ESG investment, and the achievement of SDGs, making it an unavoidable issue for the manufacturing industry. Particularly within Scope 3 (indirect emissions including procurement, logistics, use, and disposal), component procurement accounts for a large proportion. Even with small screws, the choice of materials and processing methods can significantly contribute to reducing environmental impact. (1) Carbon Materials Carbon Fiber Reinforced Plastics (CFPR/CVB) are lightweight yet possess strength comparable to iron, and they also have excellent corrosion and chemical resistance. In particular, molding technology that retains long fibers has overcome the conventional challenge of insufficient strength. Their adoption is advancing in fields requiring high performance, such as electric vehicles, aircraft, and medical equipment. (2) Recycled Metals and Alloys Utilizing iron scrap and recycled aluminum materials can significantly reduce energy consumption and CO2 emissions compared to new mining and refining. Improvements in the quality of recycled materials have made them applicable for high-precision industrial uses. (3) Biomass Resins and Environmentally Friendly Plastics Plant-derived resins contribute to carbon neutrality by reducing dependence on petroleum and utilizing the plant growth stage as a CO2 absorption source. Additionally, PVC (vinyl chloride) is being re-evaluated as a material with low CO2 emissions over its entire lifecycle due to its high recyclability. (4) Environmentally Friendly Surface Treatments Trivalent chromium treatments and ...

Procurement improvement measures to reduce logistics costs in manufacturing industry

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  • December 12th, 2025
Procurement improvement measures to reduce logistics costs in manufacturing industry
A typical indirect cost that squeezes profits in the manufacturing industry is “logistics costs.” For companies with overseas bases, including in Vietnam, international shipping fees and excess inventory can threaten business operations. This article explains how to systematically optimize logistics costs starting from procurement reform, using the latest data and specific examples. By the time you finish reading, you should have an actionable plan you can start on tomorrow. As of the end of July 2025, the Drewry World Container Index was $2,499 per 40ft container, a decrease of about 60% from the 2021 peak, but still 15% higher than pre-pandemic levels (2019) (drewry.co.uk). Meanwhile, domestic logistics costs in Vietnam account for 16-17% of GDP, significantly exceeding the world average of 10.6% (vietnamnet.vn). Although there is an advantage in labor costs, undeveloped transportation infrastructure and multi-stage transportation are the main causes of high costs. Logistics costs in the manufacturing industry are generally said to be composed of transportation costs (55%), storage costs (18%), cargo handling costs (15%), and administrative costs (12%) (internal benchmark values). Transportation and storage costs, in particular, are heavily influenced by procurement conditions (lot design and Incoterms). Large-volume orders lower the unit price. However, since inventory and warehouse costs increase, the overall cost does not necessarily decrease. Conversely, frequent small-lot orders increase the transportation unit price, which also leads to higher costs. The first thing to do is to grasp the current situation. By integrating purchasing and logistics data and setting KPIs such as PO issuance lead time, expenditure visualization rate, and inventory turnover rate, waste becomes apparent as numbers. There are reports of companies utilizing AI that have reduced logistics costs by an average of 15% and inventory by 35% (procurementtactics.com). By using man-hour automatic measurement tools like Qasee in conjunction with BI dashboards, you can move away from individual-dependent Excel management and speed up decision-making across the entire company. Optimizing order lots (recalculating MOQ <Minimum Order Quantity> / EOQ <Economic Order Quantity>) is the shortest path to simultaneously reducing transportation and inventory costs. For example, simply consolidating parts for the same destination into a weekly consolidated shipment can reduce the transportation unit price by an average of 12% compared to FCL <Full Container Load>. One of our clients switched long-tail items from monthly orders to weekly consolidated shipments, shortening inventory days from 45 to 25. As a secondary effect, supplier consolidation reduced the number of ...

Efficient screw inventory management techniques for small and large-species production

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  • December 05th, 2025
Efficient screw inventory management techniques for small and large-species production
As global competition and the diversification of consumer needs accelerate, a shift to “High-Mix Low-Volume” (HMLV) production has become unavoidable for the manufacturing industry. To supply a wide variety of product variations in short cycles, even the slightest delay or inventory shortage can bring the entire production line to a halt. Screws, in particular, which determine the final quality of a product, become extremely difficult to manage as the combinations of size, material, surface treatment, and strength classification increase exponentially. The dilemma of holding excess inventory for fear of stockouts, which pressures storage space and cash flow, versus cutting back too much and inviting line stoppages or increased costs from emergency procurement, is a major challenge that plagues on-site managers. This article is written for managers in production control, purchasing, and quality control who face these issues. It explains practical know-how to achieve both “optimal inventory” and “cost optimization” simultaneously. We will cover the latest approaches in screw inventory management, from “visualization” using IoT and data analysis to demand forecasting, automated replenishment, and enhanced traceability. Drawing on the expertise of Ohta Vietnam, which has supported numerous implementations in the ASEAN region, including Vietnam, we will present concrete solutions. First, let’s organize the specific challenges of screw inventory in the HMLV era and then delve into the solutions. Due to a growing preference for customization and shorter market lifecycles, product lifecycles are shortening year by year. As a result, manufacturing sites have been forced to transition to a system of supplying “many product types” in “small quantities” with short lead times—in other words, High-Mix Low-Volume (HMLV). Fastening components like screws are directly linked to changes in finished product specifications, making them one of the parts most affected by the increase in variations. Parts procurement, which once simply involved bulk purchasing of general-purpose items, now requires sophisticated operations, from item number organization to replenishment timing. Diversification of Sizes: Part numbers are subdivided by head shape, length, and nominal screw diameter. It’s not uncommon for a single M3 screw to have dozens of variations in length and material. Combination of Materials and Surface Treatments: In addition to stainless steel and alloy steel, requirements for surface hardening and anti-rust coatings cause the number of stock-keeping units (SKUs) to increase exponentially. Differences Between Lots: In the automotive and medical device industries, lot tracking is mandatory, requiring separate storage and retrieval for each lot number, even ...

The impact of procurement speed on manufacturing industry – What is the key to shortening delivery times?

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  • November 28th, 2025
The impact of procurement speed on manufacturing industry – What is the key to shortening delivery times?
Procuring parts in the Asian region, including Vietnam, is attractive for its ability to build a flexible supply chain while mitigating the effects of currency exchange and geopolitical risks. However, no matter how much costs are reduced, if delivery times are delayed, market opportunities can be missed, and brand value can be damaged. This article explains the benefits of increasing procurement speed and concrete measures to achieve short delivery times. The keywords are “procurement speed” and “Vietnam procurement.” Procurement speed refers to the total lead time from placing an order until the parts arrive at the factory and are put into the production line. By analyzing it in three parts—order lead time, transportation lead time, and customs clearance/inspection lead time—bottleneck processes can be visualized. Improving procurement speed yields the following three effects: Shorter Delivery Times: Enables response to customer-required lead times with a comfortable margin. Inventory Compression: Reduces safety stock and improves cash flow. Flexible Response to Market Fluctuations: Allows for immediate response to demand shifts, preventing lost opportunities. The background for the focus on Vietnam procurement lies in its proximity to manufacturing bases and its cost competitiveness. By having the production and procurement countries be the same or adjacent, it is possible to shorten the typical 14-day sea transport to as little as 5 days by utilizing land or air transport. Furthermore, by selecting Incoterms DAP (Delivered at Place) / DDP (Delivered Duty Paid) and entrusting customs clearance to a local forwarder, an additional reduction of 1-2 days can be expected. “Visualization” is essential for improving procurement speed. By attaching RFID tags to screws and fastening parts and implementing a system that automatically scans them upon warehouse departure, inventory levels and locations are reflected in the cloud in real-time. At OHTA Vietnam, we link IoT sensor-equipped stockers with our production management system to realize automated ordering in response to demand fluctuations. As a result, we have shortened procurement lead times by an average of 18%. Quality trouble is the biggest factor in delivery delays. By completing primary inspections locally, you can prevent re-transportation and rework when defects occur. At the articulated robot automated inspection line provided by Ohta, we perform 100% automated inspection for thread defects and dimensional tolerances, issuing PPAP reports on the same day. The post-shipment claim rate is maintained at 0.01% or less. The number of days for safety stock is calculated as: (Max Demand × ...

Key points and success stories of screw procurement in the Vietnamese market

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  • November 21st, 2025
Key points and success stories of screw procurement in the Vietnamese market
In recent years, industrial agglomeration in Vietnam has been rapidly advancing, particularly in the machinery, electronics, and automotive sectors. Japanese manufacturers are entering the local market one after another, accelerating the move to increase the local procurement ratio for parts. Among these parts, screws (fasteners such as bolts, nuts, and biscuits), while not accounting for a large percentage of production costs, are pivotal components whose quality defects can affect the reliability and safety of the entire product. This article organizes the merits, risks, and key points of procuring screws in Vietnam, and presents practical tips through success stories supported by OHTA Vietnam. In Vietnam’s screw-related industry, an increasing number of manufacturers are equipped with production lines that comply with international standards such as JIS, ISO, and ASTM, thanks to foreign-led capital investment. There are two main procurement channels: ① direct purchasing from local manufacturers, and ② via Japanese or local trading companies. The former offers high price competitiveness but can be cumbersome in negotiating MOQ (Minimum Order Quantity) and delivery times. The latter has lower risks in terms of language and quality assurance and can flexibly handle high-mix, low-volume orders, but a margin is added for that service. Looking at the cost structure, labor costs remain competitive at about one-third of China’s and about half of Thailand’s (as of 2025, from JETRO’s “Vietnam Wage Trends 2025 Edition”). Even with a strong yen and a weak dong, the potential for a 15-25% reduction in total costs, including transportation fees, is a significant advantage. Key Points for Quality Control: For torque value management, the combined use of calibrated torque wrenches and SPC (Statistical Process Control) is effective. The mainstream materials are SUS304/SUS316 (austenitic stainless steel), but cases of using carbon steel + trivalent chromate to comply with RoHS are increasing in recent years. Handling High-Mix, Low-Volume Orders: For special screws for medical equipment and industrial robots, selecting a CNC integrated factory that can handle lots of 500 pieces or less can shorten the lead time by an average of 40%. IoT Application Example: At OHTA Vietnam, we have introduced a QR code-based inventory management system that automatically uploads manufacturing lot information to the cloud. This has reduced the time required for tracking investigations by 70% compared to conventional methods. Logistics Optimization: Incoterms are based on CIP (Carriage and Insurance Paid To), securing three sea line shipments per week from Haiphong Port to ...

Logistics efficiency in manufacturing: Optimizing supply chain in screw procurement

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  • November 14th, 2025
Logistics efficiency in manufacturing: Optimizing supply chain in screw procurement
To keep production lines running, it is essential to procure every component, even a screw weighing just a few grams, reliably and at the right time. However, on the actual factory floor, numerous challenges arise daily, including setting order lots for screw procurement, managing transport lead times, and securing inventory space. This article provides a practical approach to achieving lead time reduction, logistics efficiency, and cost reduction by taking a comprehensive look at the entire supply chain, starting with screw procurement. First, for our target audience—purchasing, production control, and management personnel in high-mix, low-volume manufacturing—we will re-examine the impact of screw procurement on the supply chain and clarify how its efficiency directly contributes to company-wide profits. Next, we will introduce strategic methods such as inventory optimization based on demand forecasting, and supplier consolidation/multi-sourcing, linking them with the latest trends in Asian manufacturing hubs, including Vietnam. Furthermore, we will explain specific measures step-by-step, such as real-time visualization through the implementation of WMS (Warehouse Management System) and TMS (Transport Management System), automation of screw standard management like ISO/JIS, and optimization of warehousing and transportation with an eye toward decarbonized logistics. By the end of this article, you will have a checklist and a roadmap that you can immediately apply to your company’s supply chain. This article explains the key points of supply chain optimization, starting from the perspective of screw procurement. Fastening components such as screws and bolts account for a low percentage of the total product cost, around 1-3%. However, they are “high-risk, low-cost” elements that can dramatically increase total costs if they trigger a line stoppage or quality defects. This is where the perspective of TCO (Total Cost of Ownership) becomes crucial. By quantifying not only the unit price but also storage fees from order lots, transportation costs, inspection and sorting labor, re-procurement costs for non-conforming parts, and even opportunity loss from line downtime, we can visualize the impact of screw procurement on overall logistics costs. TCO = Purchase Price + Transportation Cost + Inventory Holding Cost + Quality Risk Cost + Line Stoppage Loss For example, if you bulk-purchase a three-month supply of screws used at a rate of 5,000 pieces per month at a unit price of 5 yen, the order amount is 75,000 yen. However, when you add inventory holding costs (warehouse space efficiency, interest equivalent), stocktaking work, and labor costs, it is not uncommon for the ...
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