池田金属工業 List of Products and Services

Since thread seizing occurs at contact surfaces such as the threaded part and the head seat surface, enhancing the surface properties of bolts and similar components through some form of surface treatment is effective as a countermeasure against thread seizing. When we think of surface treatment, we often imagine processes like plating or painting for screws, but in this context, surface treatment is not limited to those methods. It also includes processes that utilize heat or involve physical modifications to the surface, referring to a broader definition of surface treatment in its original sense. Now, let me introduce some effective surface treatments. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.*

• Other consumables

To suppress the seizing of screws, treatments that enhance the surface properties of bolts and similar components, aside from applying lubricants, include heat-based surface treatments and physical processing, which are also effective. Now, let's take a look at what other methods are available. Nitriding, which uses nitrogen to harden the surface, involves infiltrating nitrogen (N) into the surface of steel to create iron nitride (FeN), a compound with iron (Fe). Depending on the type of nitriding, this iron nitride can be quite hard, resistant to wear, and has high sliding properties, making nitriding effective in suppressing screw seizing. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.*

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No matter what measures are taken, it is difficult to completely prevent screw seizing, which is quite a troubling issue. So, what should be done when seizing occurs? "The most reliable method is to cut and destroy the seized bolt or nut," but actually cutting it can be quite challenging. It may depend on the screw size, but the task can take several tens of minutes and involves risks. Moreover, if other components are damaged in the process, it could be a serious problem. Therefore, this should be considered a last resort. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.*

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Metals can change their properties, such as hardness and strength, through heating and cooling. This process is called heat treatment. When we think of items around us that have undergone heat treatment, scissors and knives come to mind first. The reason for heat treating cutting tools is, of course, to ensure they do not chip and can cut well. Additionally, heat treatment is often applied to screws as well. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.*

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Through heat treatment, the properties of steel mainly change in four ways: "the steel becomes harder," "the steel becomes tougher," "the structure of the steel becomes uniform," and "the steel becomes softer." Additionally, there are two main types of heat treatment applied to screws. "Overall heat treatment" is a process that changes the properties of the entire steel, making it stronger, harder, or conversely, softer. "Surface heat treatment" is a process that changes the properties only of the surface of the steel, primarily hardening the surface.

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It is a type of overall heat treatment applied to medium to high strength classifications that are generally distributed. The strength classification refers to the numerical representation of the strength of screws, and the medium strength classification generally distributed here mainly refers to 8.8 in the case of threaded components like bolts. Now, quenching is primarily aimed at hardening steel, and it is mostly performed in conjunction with tempering, which will be discussed next time. The hardening of steel means it becomes more resistant to impacts and also more resistant to wear caused by friction. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.

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Generally, bolts with a medium strength or higher, specifically those classified as 8.8 or above, are hardened to make the steel harder. However, if left hardened, they become hard but brittle and prone to breaking, meaning they lack toughness. Therefore, it is necessary to reheat the steel immediately after hardening to enhance its toughness. This toughness is referred to as "toughness," and by increasing toughness, the durability against stretching and twisting is improved. This process is called "tempering." *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.*

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Screw components such as bolts and nuts are often made through plastic processing, specifically through cold forging, where the material is processed at room temperature. However, depending on the size and shape, there are cases where steel is heated and processed through hot forging. This hot forging disrupts the fiber structure of the steel, leaving internal stresses within it, which are the forces that resist when external forces are applied to the steel. This is referred to as "internal stress" or "residual stress," and if left unaddressed, these internal stresses can lead to dimensional changes over time. The process of reducing this internal stress is called "annealing," which helps to uniform the fiber structure of the steel and eliminate the residual stresses, thereby suppressing the occurrence of dimensional changes. *For more detailed content of the blog, please refer to the related links. For further inquiries, feel free to contact us.*

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What happens when we talk about "annealing" this time is that the steel becomes "softer." When you hear that it becomes softer, you might think it leads to a loss of power or that the steel becomes weaker, and you might wonder why we would intentionally make hard steel softer, but that's not the case. Like the branches of a willow tree or a fishing rod, being soft means it is easier to deform, and even if it deforms, it tends to return to its original shape more easily, and it won't tear easily even when pulled, which is quite convenient in many ways. *For more details, you can view the related links on the blog. Please feel free to contact us for more information.*

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There are two types of heat treatment applied to screws: overall heat treatment and surface heat treatment. I will talk about surface heat treatment, which literally hardens the surface. Surface heat treatment can be broadly divided into two methods: one is to heat elements that lead to hardening, such as carburizing and quenching, allowing them to permeate from the surface, and the other is to heat only the surface of materials that can be hardened, such as high-frequency quenching. *For more details, you can view the related links on the blog. Please feel free to contact us for more information.

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Surface heat treatment involves two methods: one is to heat elements that lead to hardening, such as carburizing and quenching, allowing them to permeate from the surface, and the other is to heat only the surface of materials that can be hardened, such as high-frequency quenching. This time, I will talk about nitriding. Nitriding is a heat treatment that creates iron nitride (FeN), a compound of nitrogen (N) and iron (Fe), on the surface of steel, making only the surface hard. There are two types: gas nitriding, which uses gas, and salt bath nitriding, which uses a salt bath furnace. *For more details, please refer to the related links on the blog. Feel free to contact us for more information.

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In recent years, it has become quite rare to see, but slotted screws have advantages that other recesses do not have. For example, when adjusting screws for liquids, gases, or the position of objects, if you rotate it 90 degrees to the right, the appearance remains the same for cross slots, hex slots, and hexagonal sockets, but in the case of slotted screws, the appearance shows a vertical or horizontal line, making it immediately obvious when rotated 90 degrees. *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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The standards established for each product are referred to as "specifications." In the case of screws, there are various levels of specifications based on international standards such as ISO standards, which are commonly used across countries, as well as JIS standards, which are used within Japan and are generally compliant with ISO standards. Additionally, there are industry standards and organizational standards used by specific industries or groups. A key point to note regarding screw specifications is that the screws available in the market may not necessarily align with the latest standards. *For more details, please refer to the related links. Feel free to contact us for further information.*

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What is the difference between standard products and supplementary products? In the case of hex bolts, the dimensions differ in some sizes. For M10, the width of the hex head (also known as the distance across flats or the width across two sides) is 16 millimeters for standard products and 17 millimeters for supplementary products, which is a difference of just 1 millimeter. Just 1 millimeter. Of course, those who use hex bolts may not think much of it. A difference of 1 millimeter means you need to change the tool for tightening and loosening. *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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In terms of specifications, there are other items besides hex bolts and hex nuts that require attention. For example, there are small screws and tapping screws, which also have counterparts that correspond to the main specification items and those that correspond to supplementary items. Like hex bolts and hex nuts, many of the small screws and tapping screws distributed in Japan are supplementary items. *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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There are three main types of materials for tangible objects: metals (ferrous and non-ferrous metals), organic materials (such as resins and rubber), and inorganic materials (such as glass and ceramics). Additionally, there are composite materials that combine two or more different materials (commonly known as composite materials, such as fiber-reinforced plastics). *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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Let's take a look at the materials that will be used for screws from now on. The most common low-strength material is cold drawn carbon steel wire, which is used for various types of screws such as hex bolts, hex nuts, small screws, and tapping screws. "Cold drawn carbon steel wire" is a bit of a mouthful and not very approachable, so let's use an abbreviation to make it easier to say. *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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The number that follows SWCH refers to the carbon content, which typically ranges from 8 to 18, but this is expressed as a value 100 times the actual content. In other words, if it is 8, the carbon content is 0.08%. These are low carbon steels, and in terms of the strength classification that will be mentioned later, they are used to make screws of the so-called low strength category, such as 4.8. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.

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Alloy steel, similarly, has formal names like carbon steel for machine structures and alloy steel for machine structures, which can be a bit difficult to approach, so I think it's easier to remember them by their abbreviations. One type of alloy steel for machine structures is SCM material. Among SCM materials, SCM435 and SCM440 are commonly used for screw components, and the meaning of the numbers is that the last two digits, 35 or 40, represent the carbon (C) content (0.35% or 0.40%). *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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Regarding stainless steel with good corrosion resistance, I don't think there are any particular difficulties in saying or remembering it, but at this point, let's remember the abbreviation SUS as well. For the materials introduced so far, SS, SWCH, and SCM are referred to in conversation as "Esu Esu," "Esu Daburyu Shii Eichi," and "Esu Shii Emu," respectively. However, for stainless steel, we never say "Esu Yuu Esu"; instead, we say "Suten (resu)" or "Sasu." *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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The "Interesting Lecture on Screws in Otsu" is a group seminar composed of popular content from previous sessions, such as "Differentiating the Use of Screws," "Screw Strength Classification," and "Measures Against Screw Loosening." In the latter part regarding loosening, we will discuss the causes of troubles and their solutions. Additionally, we have previously conducted educational seminars such as "Interesting Lecture on Screws Online Version" and "Tapping Screw Torque Curve Analysis Seminar." 【Event Overview】 ■ Date and Time: October 19, 2023 (Thursday) 13:30 - 16:30 ■ Venue: Piazza Omi (Shiga Prefectural Citizen Exchange Center) Room 204 ■ Address: 1-1-20 Hinohama, Otsu City, Shiga Prefecture *For more details, please refer to the related links or feel free to contact us.

• Technical Seminar

Screws are primarily used for "fastening," which involves joining two or more items together. The underlying premise is that the screw is smaller than the items being fastened, known as the fastened objects. For example, screws that are larger than the frame of glasses or thick screws are generally not used and likely cannot be used. *For more detailed information, you can view it through the related links. Please feel free to contact us for more details.*

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The structure of a screw consists of the following three basic pieces of information: type, material, and size. This applies universally to any object. To slightly deviate from the topic of screws, if we consider canned coffee, it would look something like this. *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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The three basic pieces of information about screws, (1) type, (2) material, and (3) size, can be further subdivided into the following eight items: Type: (1) screw shape, (2) head shape, (3) recess, (4) standard, Material: (5) material, (6) strength classification, (7) surface treatment, Size: (8) notation method. Since there are countless types of screws in the world, it is impossible to remember all the characteristics of each type, but thinking of them as combinations of the eight items makes them easier to remember and organize. *For more detailed content of the blog, you can view it through the related links. Please feel free to contact us for more information.*

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Now, let's go through the eight items that make up a screw, one by one. I believe that such diligent work is necessary at the beginning of screw selection. This allows for the appropriate use of different screws. The keyword for this series of columns titled "Screw Strengthening Guide" is "appropriate use." First, let's discuss screw shapes. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.*

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Next, from the perspective of cost, in order from lowest to highest, it goes as follows: drill screws → tapping screws → bolts and small screws. The cost referred to here is not only the cost of the screws themselves but also includes the expenses for the work necessary for fastening, commonly known as labor costs, which encompasses direct labor costs. This is largely influenced by the number of processes involved. Drill screws can be fastened directly without any pilot holes or internal threads, so roughly speaking, it can be done in one process. *For more detailed content of the blog, you can view it through the related links. For further inquiries, please feel free to contact us.*

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Next, let's discuss the differentiation in the use of screws with heads. As representative examples, we will look at small screws with a cross recess and bolts with a hexagon socket. First, let's consider the small screw with a cross recess. In this category, let's take the "pan head," which has the highest shipment volume at Ikekin, as our standard. By using a truss head, which has a larger diameter than the pan head, the seating surface, which is the contact area between the screw and the counterpart material, becomes more stable, and the tendency for the screw to sink into the counterpart material is alleviated. *For more detailed information, please refer to the related links on the blog. Feel free to contact us for further inquiries.

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In terms of head size, the bind head is between the pan head and the truss head (not exactly in the middle). It can be used when the truss head is too large for the workpiece, but the pan head might cause it to sink into the material. Additionally, since the depth of the cross hole is slightly deeper than that of the pan head depending on the screw diameter, it can be said that the cross hole is less likely to be damaged in theory. Next, regarding the flat head, its main feature is that after tightening, the head does not protrude from the workpiece and becomes flat. *You can view the detailed content of the blog through the related links. For more information, please feel free to contact us.*

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For bolts with hexagonal holes, we will consider the so-called standard hexagon socket bolts as the reference. Although it is slight, using hexagon socket button bolts with a larger head diameter can stabilize the seating surface, which is the contact area between the screw and the counterpart material, and alleviate the sinking (dimpling) into the counterpart material. However, it seems that button bolts are often used to create a neat appearance in the visible parts of the fastening section. *For more details, you can view the related links on the blog. Please feel free to contact us for more information.*

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The term "recess" refers to "depressions" or "indentations" in English, specifically in the context of screw components, such as "cross slots" and "hexagonal sockets." The role of the recess is to provide a means for tools to fit into these indented areas, allowing rotational force to be applied to the screw, thereby giving it driving power. In addition to cross slots and hexagonal sockets, there are also "slotted" types and star-shaped "hexalobular" (6-lobe) designs with six protrusions. For reference, if arranged in the order of their introduction, they would be as follows. *For more detailed information, please refer to the related links. Feel free to contact us for further inquiries.*

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Compared to a cross-shaped socket, a hexagonal socket has the advantage of being able to "tighten screws with strong force more easily than with a cross-shaped socket." In addition to the force needed to turn the screw, the cross-shaped socket has a shape like a mortar, which requires downward pressure on the tool from above. If the upward force is even slightly weak, the tool will lift upwards, making it impossible to tighten the screw. *For more detailed information, you can view it through the related links. Please feel free to contact us for more details.

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Here is a case where we proposed "Nord-Lock washers" to an industrial machinery manufacturer. They were using hex socket bolts (CAP) in their binding equipment, but there was an issue with loosening occurring after delivery. After our proposal, the reports of loosening troubles, which had been occurring almost every month, dropped to zero. [Overview of the Issue] - Hex socket bolts (CAP) are used in the binding equipment, but loosening occurs after delivery. - There were 2 to 3 reports each month, and we had to visit the client for maintenance each time. *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed the identification of the cause of loosening and permanent countermeasures through hypothesis establishment and dimensional inspection using an image measurement device for an industrial vehicle manufacturer. There was an issue where the embedded bolts used to secure the tire wheels of forklifts were falling off after being delivered to the customer. We shared knowledge regarding the threaded parts' dimensional measurement using the image measurement device and proposed clearly stating tolerances on the drawings to ensure accurate communication of information among design, quality control, procurement, and suppliers. [Overview of the Issue] ■ The embedded bolts used to secure the tire wheels of forklifts were falling off after being delivered to the customer. ■ If they fall off while in operation, it could lead to a serious accident, so it must be resolved urgently. *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed an alternative for a left-handed hex socket bolt that has been discontinued by the manufacturer and is no longer available in the market for a textile machinery manufacturer. The M3×7 uncoated hex socket bolt (left-handed) used in textile machinery was discontinued, and without finding an alternative product, the production line would come to a halt, impacting sales. We proposed machining the dimensions of the left-handed hex socket bolt and painting the head, allowing for the selection of right-handed and left-handed screws without changing the screw size, and we were able to deliver the product by the desired deadline. [Overview of the Issue] - The M3×7 uncoated hex socket bolt (left-handed) was used in textile machinery, but production by the manufacturer has ended, and it has been discontinued. - If an alternative product cannot be found, the production line will stop, affecting sales. *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed "Nord-Lock washers + Zorbest coating" to the manufacturing industry. While implementing measures to prevent failures caused by loosening screws, there was a challenge in wanting to achieve high precision in axial force using lubricants, as most anti-loosening products could not be used in conjunction with lubricants. After the proposal, we successfully manufactured vehicle parts with high difficulty in design, contributing to the reduction of labor in the lubricant application process. [Overview of the Challenges] - To meet the demands of the end user (railway company), the design of vehicle parts had to be more stringent than usual. - While wanting to prevent failures caused by loosening screws and achieve high precision in axial force, most anti-loosening products could not be used with lubricants. - Even if there were anti-loosening products that could be used with lubricants, the application process was labor-intensive. *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed the clarification of details for special screws, which became unclear due to the closure of a factory, using knowledge of drawing production and inspection tools in the plant maintenance industry. During the maintenance of a rod mill, the screws used became unavailable, making maintenance impossible. After our proposal, we were able to manufacture screws identical to the samples by selecting a manufacturing method according to the size and shape of the screws. [Overview of the Issue] - The factory that was commissioned to manufacture the special-shaped screws went out of business, resulting in the unavailability of screws needed for maintenance of the rod mill. - The only remaining item was a sample of the screw, which provided information only about its shape and material, as well as rough dimensions. - Three sizes of screws were needed in the quantities listed below by the maintenance scheduled to start in four months, and without these screws, maintenance of the rod mill could not be performed. *For more details, please refer to the related links or feel free to contact us.*

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We would like to introduce a case where we proposed replacing the truss screws with the ultra-low head screw '310 Slim' in the automotive industry. With truss screws, the protruding head of the screw posed a challenge as it would get caught and not fit properly. After the proposal, assembly could be done without interference with other components, and when placing the housing inside the vehicle, the head no longer got caught. [Overview of the Challenge] - The size of this compact vehicle is smaller than conventional products, and each component is required to be miniaturized and lightweight. - Although truss screws are typically used for fastening, the design calculations indicated that the protruding head would interfere with other components inside the housing. - The space on the vehicle side for inserting the housing is also narrow, and with truss screws, the protruding head would get caught and not fit. *For more details, please refer to the related links or feel free to contact us.

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Here is an example of a proposal for "rust prevention through Disgo treatment" made to a construction manufacturer. The customer was using stainless steel post-installed anchors to secure a seaside pier, but rust was occurring during low tide, posing a risk of collapse. They requested a solution to this issue. We proposed Disgo treatment, which can extend the lifespan of the components, thereby strengthening rust prevention and reducing the possibility of pier collapse. [Overview of the Issue] - Stainless steel post-installed anchors were being used to secure the seaside pier, but rust was occurring during low tide. - There was a risk of collapse if the post-installed anchors broke, so a solution was needed. *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed to a manufacturer of machine tools and industrial machinery to produce adjustment screws from scratch as per their request. During mass production, a request for the arrangement of adjustment screws was made to the purchasing department, and upon checking on an e-commerce site, it was found that the costs were high and did not fit the budget for purchasing the mass production lot (700 pieces). After our proposal, we were able to provide the screws at approximately 45% lower cost than the e-commerce site, taking into account the lead time (actual working days: 30). [Overview of the Issue] - During the prototype phase of a new machine tool, the design department intended to use "adjustment screws" available on the e-commerce site for the legs of the machine. - When a request for the arrangement of adjustment screws was made to the purchasing department during mass production, it was discovered that the unit price was high and did not fit the budget for purchasing the mass production lot. - Since they did not want to make significant changes to the specifications, they were considering how to obtain the screws at a lower cost. *For more details, please refer to the related links or feel free to contact us.*

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Here is a case study of proposing "Color Tangless" to an aluminum processing manufacturer. In this manufacturer, after inserting Tangless inserts for thread reinforcement into the aluminum processing material, they deliver the products to the final assembly manufacturer. However, it was frequently occurring that the Tangless inserts were not inserted when the customers assembled the products. After the proposal, the visual confirmation alone sufficed, reducing the work time by about half, and since there are no longer any insertion omissions, it also prevents the loss of time and trust due to after-sales responses. [Case Overview] ■ Issues - Frequent occurrences of Tangless not being inserted - High inspection burden for preventive measures ■ Requirements for Solving the Issues - A fundamental method to eliminate insertion omissions - A simpler method that eliminates the need for bolt checks after insertion *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed "switching manufacturers/automating the bagging process" to a battery manufacturer. There was a frequent issue with the small-diameter brass hex nuts used in battery production, where "the taps were cut at an angle." After our proposal, and following audits of two manufacturers, product defects have not occurred since the process changes were approved. 【Case Overview】 ■ Issue - There was a frequent issue with the small-diameter brass hex nuts used in battery production, where "the taps were cut at an angle." ■ Requirements for Solving the Issue - Select manufacturers that can ensure accurate quality control (to prevent occurrence) - Ensure that defective products can be detected during the bagging and inspection processes (to prevent outflow) *For more details, please refer to the related links or feel free to contact us.

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Here is a case where we proposed the "Nord-Lock Washer" to a food processing manufacturer. In the final stage of packing the manufactured liquid, screws used in the equipment line fell off and were shipped without anyone noticing, resulting in contamination of the product. After our proposal, there have been no signs of screw detachment, and the emergency inspection work has been eliminated, leading to a reduction in the burden on the workers. [Overview of the Issue] ■ Screws used in the equipment line fell off and were shipped while contaminating the product without anyone noticing. ■ The issue was discovered by chance during an inspection at a retail store, leading to a halt in production and a recall of all products. ■ Since then, all areas with potential for detachment have been addressed with emergency measures. ■ The pre-shift inspection work has become an excessive burden, so we want to implement a fundamental solution. *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed "reducing the manufacturing process and increasing production lots" to an industrial machinery manufacturer. The customer was purchasing low-head type special-shaped hexagon socket bolts M2 from an e-commerce site, but due to high unit prices and an increasing quantity needed, they expressed a desire to reduce costs. We proposed a change in the manufacturing method, which was adopted without any issues and was equivalent to or better than the conventional products, resulting in significant cost reductions. [Case Overview] ■ Issues - Costs had become excessively high - The shape was not particularly difficult to manufacture, despite being outside JIS standards ■ Requirements for Solving the Issues - Reduction of costly machining processes - Establishing a production lot that ensures stable lead times *For more details, please refer to the related links or feel free to contact us.

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Here is a case study where we proposed "Super Bolt" to a manufacturer of injection molding machines. The customer had a request to eliminate both the physical burden and dangers associated with the tightening methods used by workers. After implementation, it became possible to secure connections safely without the use of hammers or special tools. 【Case Overview】 ■Issues - The M150 tie rod (bar) was broken. - A tightening method that posed physical burdens and dangers to workers was being used. ■Requirements for Solving Issues - Anyone should be able to accurately achieve the design axial force for large-diameter bolts. - Avoid excessive torsional stress on the bolts. *For more details, please refer to the related links or feel free to contact us.

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We would like to introduce a case where we proposed "Non-Sert" to a vehicle-mounted device manufacturer. Frequent thread stripping (commonly known as "screw stripping") was occurring at fastening points using tapping screws (with the counterpart material being thermoplastic resin). After the proposal, stable production became possible for anyone without relying on the skills of a craftsman. 【Case Overview】 ■ Issues - Frequent thread stripping occurred at fastening points using tapping screws. - Only experienced workers could ensure reliable assembly. ■ Requirements for Solving the Issues - Selection of appropriate screws that match the fastening components. - Selection of appropriate conditions and redesign of specifications through torque testing. *For more details, please refer to the related links or feel free to contact us.

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