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

Screw You use screws every single day — you just don’t notice them. They’re inside your phone, furniture, motorcycles, cars, computers, door locks, home appliances, factory machines, medical instruments…Small as they are, without screws, the world simply cannot be assembled, cannot operate, and cannot be repaired. This article will help you understand screws quickly — their functions, materials, and where they are used. --- 1. What is a screw and why is it important? A screw

Metric and Imperial In hardware parts, machining, and equipment maintenance, it’s common to encounter a confusing situation: you only want to find a screw or a pin, yet the specifications appear in two completely different formats — one written as M4, M6, M8 (metric), and another as 1/4"-20 or #8-32 (imperial). Many people wonder:“Why aren’t these specifications unified?”“Since they look similar, can they substitute for each other?” The answer is: No.Metric and imperial syste

1. Why Do Plastic Parts Often Contain Metal Nuts? Brass Insert Nut Ever had this happen?You’ve tightened a screw into a plastic housing many times — eventually, the screw hole gets loose, won’t grip, and can’t hold anymore. That’s exactly when the Brass Insert Nut comes to the rescue. The concept is simple:Embed a brass nut inside the plastic hole so the plastic part can have a metal-strength threaded anchor. These nuts are installed using heat, ultrasonic vibration, or press

1. What Is a Retaining Ring? A retaining ring (circlip) is a small fastening component used to prevent parts from sliding axially along a shaft.It ’s commonly seen in motors, gears, and bearings — essential for keeping machines running smoothly. However, depending on the region or industry, retaining rings follow different design and dimension standards.Globally, the three most recognized systems are JIS (Japan), DIN (Germany), and ANSI (United States). Let’s explore the key

Although it may look insignificant, the flat key plays a crucial role in preventing slippage and ensuring stable torque transmission...

Self-Locking Retaining Ring When people hear Self-Locking Nut (SPN / Press-Fit Nut, Self-Locking Retaining Ring), they often assume it...

In machines and structures, washers are the most common yet most overlooked small parts. Placed between the screw/nut and the mating...

Clevis Pin In various machines and structures, the Clevis Pin is a simple yet versatile fastener. It typically consists of a pin with a...

When installing C-type retaining rings (circlips / retaining rings), relying on bare hands or non-specialized tools can lead to slipping,...

spring pin In many machines and structures, a spring pin is a fastener that relies on its own elasticity to fasten and locate parts.It is typically a slotted, cylindrical pin that expands against the hole after insertion, creating a tight fit that prevents loosening. This property lets spring pins both withstand shear and absorb vibration, making them an indispensable “invisible guardian” in many systems. --- How to Determine the Right Spec？ When selecting a spring pin, the

In many machines and structures, the cotter pin is a simple-looking part that provides crucial safety. Commonly used with nuts,...

Parallel Key In mechanical transmission and assembly, the parallel key is a small yet crucial component that determines whether parts operate securely. Installed between the shaft and hub (such as gears, pulleys, and couplings), it transmits torque and prevents relative sliding. If the size is chosen incorrectly or installed improperly, it can lead to loosened parts, reduced mechanical precision, or even shaft damage. --- How to Select Parallel Key Size Selection is mainly ba