ISO 2338 Stainless Steel Dowel Pins | Sheng Fong Precision ISO 2338 is an international standard for unhardened parallel pins (Parallel Pins, Unhardened). In practical applications and supplier catalogs, it is often compared alongside the German DIN 7 standard. However, the two are not completely identical. ISO 2338 measures length end-to-end (including chamfers), while DIN 7 nominal length excludes the end form, meaning the actual total length may be 0.3–8.0 mm longer than t

types of nuts In most fastening structures, nuts are typically installed externally. However, there is one exception: when the thread needs to be embedded inside the material. This is where insert nuts come into use. If you have encountered any of the following issues: Plastic parts strip after a few uses Threads in aluminum parts break Screws become looser the more they are tightened Structures become unstable after repeated assembly and disassembly In most cases, the issue

nut threads type When selecting nuts or screws, many people focus on size first. However, in practice, the thread is the key factor that determines whether parts can be properly fastened. Common thread classifications include: Metric threads vs. imperial threads (UNC / UNF) Right-hand threads vs. left-hand threads Special-purpose threads (such as pipe threads and power transmission threads) These categories may seem simple, but if misunderstood, they can lead to issues such a

Nut Materials When selecting nuts, many people first look at size or type. In reality, however, material and surface treatment are the key factors that determine the final performance. Even if two nuts are the same size, using the wrong material may result in rust, stripped threads, insufficient strength, or even rapid failure in the actual environment. Many on-site problems may seem like poor nut quality, but the real issue is often whether the correct material was selected.

nut Most nuts look similar from the outside, but in reality, every design is made to solve a specific problem. When many people choose a nut, their first reaction is: “Just find the right size.” But the correct size is only the most basic requirement. If the type is wrong, problems can still occur—unstable fastening, loosening, or even having to redesign the entire structure. If you have ever been unsure which type to use, or only realized after assembly that it was the wrong

Nuts Among hardware parts, the nut (NUT) is one of the most overlooked—and yet one of the most essential. Many people instinctively think: “A screw is enough.”But in reality, there are very few situations where a screw can work properly on its own. In most fastening applications, a nut is needed to truly clamp and secure the structure. From the most basic hex nut to insert nuts embedded in plastic parts, choosing the right type is where reliable fastening begins. --- 1. What

In practice, many people have encountered this situation: A screw looks about the same size, but it just won’t go in — or it gets stuck halfway. Most people first suspect size or tolerance issues.However, in most cases, the real problem is: the thread system is different. --- 1. What Are JIS and ANSI / ASME Thread Systems? In screw design, the whole world does not use the same standard. The two most common systems today come from different countries: JIS (Japanese Industrial

screw threads In practice, many people encounter this situation:A screw can be threaded in, but no matter how tight it is, it won’t hold properly—or worse, it starts leaking or loosening. The first assumption is often incorrect sizing.However, in many cases, the real issue is: the wrong thread type was used. The most commonly confused types are:Machine Thread and Pipe Thread (often called “pipe thread” on site) Although they may look similar, their design purposes are complet

Screw surface treatments In many industrial applications, the durability of screws is not determined only by material and strength—surface treatment also plays a critical role. For example, a carbon steel screw without any treatment may rust quickly. However, with proper surface treatment, its corrosion resistance can be significantly improved. Different surface treatments vary greatly in corrosion resistance and application environments. Therefore, when selecting screws, sur

Thread Classes 2A / 3A and 55° vs 60° Thread Angles When selecting screws, many people first look at size, material, or head type.However, in industrial equipment and precision mechanisms, the factors that truly affect fit quality and service life are often more subtle technical details: Thread Class Thread Angle These parameters determine the precision of the fit between the screw and the threaded hole, the clearance between threads, and the stability under vibration or load

thread types When choosing screws, many people only look at size and head type. However, in industrial equipment, what truly affects stability and service life is the thread type. Among all thread designs, Machine Threads are the most fundamental type used in industrial equipment. This is because industrial machinery requires precise mating and repeated assembly, not a one-time bite into the material. --- 1. What Is a Machine Thread? A Machine Thread refers to a standard thr

When selecting screws, many people only check whether the size and thread pitch are correct.As long as it threads in, they assume it’s fine. But in real-world applications, the real differences often appear after some time: The tool keeps slipping The screw head becomes rounded Threads start stripping after a few installations It feels tight but slowly loosens The screw head protrudes and interferes with other parts These issues are usually not caused by poor material qualit

Metric,ANSI／ASME,BS In machining and maintenance, many people run into the same problem:Two fasteners look similar in size and even thread in, but they won’t tighten, and when you remove them, the threads are already damaged. In most cases, it’s not poor machining or low-quality screws—it’s simply the wrong thread system from the start. In practice, most screw threads come from three major systems: Metric threads, Unified threads (ANSI/ASME), and Whitworth threads (BS). Their

Screws When people choose screws, they usually look at size, thread pitch, and head type first.But in real applications, what truly determines whether a screw will fail is often the material. Rust, stripped threads, breakage, deformation, or loosening over time—many of these issues are not caused by poor machining, but by choosing the wrong material from the start. --- 1. Why Does Screw Material Matter So Much? In use, a screw typically faces multiple factors at the same time

In machining and hardware part supply chains, many people share the same feeling: There seem to be more and more documents—yet customers usually care about only one or two each time. The real point isn’t whether you have every document. It’s whether you can identify which stage of risk the customer is focusing on right now. --- 1. What Are the 6 Most Common Compliance Documents for Hardware Parts? In practice, the documents that appear most often—and cause the most confusio

In international trade for machining and metal parts, the most familiar question used to be:“Where is this product made?” But in recent years, more and more customers and customs/brokers have started asking a deeper sourcing question: “Where was the raw material melted?” In other words, the focus is shifting from Made in to Melted in.This change reflects a broader trend: attention is moving from “where the product was processed or assembled” to “where the raw material origina

In machining and industrial hardware supply, after customers finish confirming RoHS, REACH, and PFAS Free, the next question that often comes up is: “Do you have an EN 10204 3.1 material certificate?” For many suppliers, this document looks like just an English report—but in reality, it often becomes a key factor in whether the customer will move forward with cooperation. --- 1. What Is EN 10204—What Does It Actually Control? EN 10204 is a document standard established by the

Many machining suppliers have experienced this: A customer emails for a quote, and the first question isn’t price or lead time. Instead, they ask:“Is it RoHS compliant? Do you have REACH? Is it PFAS Free?” A common reaction is confusion—or even a bit of panic:“We only do machining. Why are they asking us this?”“Isn’t this only for electronics?”“Do we have to send everything to a third-party lab?” In reality, customers aren’t trying to make things difficult. They’re doing some

ISO、JIS、DIN、ASME The Essential Beginner’s Guide to Global Fastener Standards The reason hardware parts can be used, replaced, and serviced across machines worldwide comes down to one thing: standards. There are many standards in the world, but in fasteners and mechanical parts, you’ll most often run into these four: ISO, JIS, DIN, and ASME. This article will walk you through the origin, differences, and use cases of these four major standards in a clear and practical way, so

Global Fastener Standards When searching for screws, nuts, washers, retaining rings, or dowel pins, you may encounter a long list of standards: DIN, ISO, JIS, ANSI, ASTM, CNS, GB, BS, AS…Why are there so many? What’s the difference? How do you choose the correct one? This article breaks down the origins, differences, and real-world uses of global fastener standards in a clear and easy-to-understand way. --- 1. Why Do We Need Fastener Standards? Fasteners are mating parts —scr