• Jan 04, 2026
• News

How to Identify Chain Grade?

To identify the crane chain grade, look for a stamp on the chain, typically found about every six links.

Chains are vital components across industries, ensuring safety and efficiency in lifting, securing, and transporting operations. Understanding chain grades is crucial, as these grades determine a chain's strength, durability, and suitability for specific tasks. This article focuses on chains in cranes, how to recognize chain grades and their importance.

What is a Chain Grade?

Chain grades, denoted by numbers (e.g., Grade 30, Grade 70), indicate the tensile strength and performance of the chain material. The grade directly correlates to the chain's intended application, such as lifting, towing, or binding.

Why is Chain Grade Important?

• Safety: Using the correct chain grade prevents accidents caused by overloading or material failure.
• Efficiency: Properly graded chains enhance operational efficiency by matching strength to task demands.
• Regulatory Compliance: Certain industries require compliance with standards set by organizations like OSHA or ASTM.

Factors That Determine Chain Grades

Chain grade tells you how safe and strong a lifting chain will be for crane work. It is not just a number. It reflects how the chain was made and tested. Picking the right grade helps prevent accidents. It also protects your equipment and keeps downtime low.

1. Material Composition

The metal used to make the links determines the chain's baseline strength. Higher-grade chains are usually forged from alloy steels or specially formulated high-strength carbon steels. These alloys contain elements such as chromium, nickel or molybdenum that boost tensile strength and toughness. Stronger steels resist stretching, cracking and fatigue under repeated loads. Surface treatments — like galvanizing or specialized coatings — help protect against corrosion, which matters when your crane works outdoors or near saltwater. When you compare chains, look beyond the label and ask about the exact steel grade and any corrosion protection the maker applied.

2. Heat Treatment

Heat treatment changes the metal's internal structure to give the chain its working properties. Common steps are quenching (rapid cooling) and tempering (controlled reheating). Quenching increases hardness and strength. Tempering reduces brittleness so the chain won't snap under shock loads. Properly controlled heat treatment produces consistent performance link to link. Poor or uneven heat treatment can leave weak spots that shorten service life or cause sudden failure.

3. Markings and Identification

Clear markings are your quick check for authenticity and suitability. Good chains have grade stamps such as G70, Grade 80, or G100, plus the manufacturer's mark and often the chain size or working load limit. These stamps allow you to trace the chain back to its production batch and certificates of conformity. If a chain lacks legible markings, treat it as suspect. At receiving and during inspections, verify the marks remain readable and that the links show no excessive wear, elongation, or deformation.

Common Chain Grades and Their Uses

Choosing the right chain grade matters for safety, cost, and performance. Each grade has different steel, heat treatment, markings, and approved uses. Never assume a chain is suitable for overhead lifting just because it looks strong. Insist on proper markings and regular inspections for any chain that will be used with cranes.

1. Grade 30 (Proof Coil)

Grade 30 is made from low-carbon steel and offers basic strength for general tasks. Its tensile strength is about 30,000 psi, which makes it fine for light utility work, small tie-offs, and non-critical securing where human safety is not at stake. This grade is not heat-treated and is not rated for overhead lifting or crane hoists. If you are buying chains for any lifting application, avoid Grade 30. Also check for corrosion and elongation when you inspect these chains, because wear reduces their safe life quickly.

2. Grade 43 (High-Test)

Grade 43 comes from medium-carbon steel and is noticeably stronger than Grade 30, at about 43,000 psi tensile strength. It is commonly used for cargo tie-downs, farm equipment, and other transport-related tasks where higher strength is useful but overhead lifting is not required. Grade 43 chains are often marked by the manufacturer or stamped G43. Like Grade 30, they are not approved for overhead rigging with cranes, so if you need a chain for hoisting, pick an alloy lifting grade instead.

3. Grade 70 (Transport Chain)

Grade 70 is a heat-treated carbon steel chain made for the transportation industry and heavy securement. With roughly 70,000 psi tensile strength, it is a workhorse for truck tie-downs, load binders, and other load-securement duties. These chains are commonly finished to resist corrosion and are stamped G70. They are excellent for load restraint but generally not certified for overhead lifting or crane hoists. Note that transport chains often use a lower safety factor than lifting chains, so always verify the chain's working load limit for your use.

4. Grade 80 (Alloy Chain)

Grade 80 is an alloy, heat-treated chain designed and approved for lifting. Its tensile strength is around 80,000 psi, and it is widely used for overhead rigging, slings, and crane hoist applications. When you buy Grade 80, make sure the chain and its attachments carry matching rated markings and meet the applicable lifting standards. Alloy chain gives good toughness and fatigue resistance, but it still needs regular inspection for wear, nicks, heat damage, or elongation.

5. Grade 100 (Alloy Chain)

Grade 100 is an upgraded alloy chain that delivers higher strength at a lighter weight compared with Grade 80. With about 100,000 psi tensile strength, it lets you achieve a higher working load limit with the same link size. This makes it popular for heavy lifting, crane hoists, and demanding rigging where lower chain weight and higher capacity help handling and safety. As with all lifting chains, confirm that hooks, links, and other hardware are rated for Grade 100 and inspect components often.

6. Grade 120 (High-Performance Alloy Chain)

Grade 120 is the highest-performance alloy chain commonly available. It offers roughly 120,000 psi tensile strength and superior heat and wear resistance. Buyers choose Grade 120 for extreme lifting tasks, repeated heavy cycles, and harsh environments such as construction sites and offshore rigs. Because it is premium material, it costs more and requires compatible, rated fittings. If you consider Grade 120 for crane work, check compatibility, certification, and manufacturer guidance carefully; the extra strength is only safe when all components and procedures match that capability.

How to Identify Chain Grade?

Common chain grades include Grade 30, Grade 43, Grade 70, Grade 80 and Grade 100. Grade 30 and 43 are for light to general-duty work, like securing loads or light rigging. Grade 70 is used widely in transport and load-securing; it is strong but not designed for overhead lifting. Grades 80 and 100 are quenched-and-tempered alloy chains made for lifting and heavy rigging.

1. Examine the Chain Markings

Look closely at every link and at the master link for stamped markings such as G70, 80, or G100, plus the manufacturer's logo and batch number. These stamps are your quickest proof of grade when they are clear and consistent along the chain. Never rely only on a single worn mark; ask for documentation if anything looks unclear.

2. Check the Material Composition

Higher grades are made from alloy, and they are heat treated to raise tensile strength and toughness. Lower grades are often mild steel and are not suitable for overhead lifting. You can confirm material by requesting the chain's material specification or mill certificate, which should state chemical composition and heat treatment.

3. Assess the Color Coding

Manufacturers sometimes finish chains differently: for example, transport chains are often zinc-plated and yellow/gold, and many alloy lifting chains have a black oxide or dark finish. Color can help as a quick visual cue, but finishes vary by maker and can wear off, so color alone is not proof of grade. Use color as an initial check, then confirm with the stamped markings and the manufacturer's documentation before you decide to use or buy the chain.

4. Consult Manufacturer Documentation

Always ask the supplier for the datasheet, proof-load certificate, and the chain's declaration of conformity to relevant standards (such as EN, ISO, or ASTM). Those documents show rated working load limit, minimum breaking force, proof test results, and traceability to a batch or heat number.

Chain Grade Applications

Wire Rope and Chain Grades: Differences

Chains and wire ropes both come with strength ratings, but they are made and used very differently. Chains carry grade stamps from the maker; these stamps tell you the metal type and design strength. Higher-grade chains are heat-treated alloy. They are made for direct lifting and for use with hooks and shackles. Lower-grade or transport chains are not safe for overhead lifts. Wire rope is specified by construction (how the strands are arranged), core type, and diameter, and its strength is given as a breaking force rather than a simple grade number. You usually see wire rope in winches, hoists, and pulley systems where flexibility and abrasion resistance matter more than the link-by-link strength chains provide. For buyers, that means choose chains when you need a direct, compact connection to a load and choose wire rope when you need to run over sheaves or drums. Look for manufacturer stamps, grade numbers on chain, and specifications for wire rope construction and minimum breaking force. Inspect chains for stretched links, corrosion, or heat damage and inspect wire rope for broken wires, crushing, kinks, or core failure. Never substitute a lower-grade chain for a higher-grade one, and never use transport chain for overhead lifting. Match the component to the rated capacity of your crane and follow applicable standards and the equipment manufacturer's instructions.

Tips for Selecting the Right Chain Grade

1. Consider your application

First, think about what you will do with the chain. Lifting overhead needs different chain than towing or simple load restraint. Consider whether the load is steady or shocky, how often you will lift, and the exact attachment points and angles you will use. For overhead slings, use alloy chain that is made and rated for lifting; manufacturers and regulators treat overhead use as a special case because of the risk if a link fails.

2. Consider Environmental Conditions

Think about the environment where the chain will live. Salt, chemicals, moisture, and heat all change how long a chain will last and whether its rating stays reliable. For corrosive or marine settings, choose corrosion-resistant options — such as stainless steel or specially coated chains — and check which finishes the manufacturer recommends for your conditions. Regular inspection and correct cleaning also extend service life.

3. Verify Compliance

Confirm the chain meets the standards for the grade you need. Grade 80 and Grade 100 alloy chains have specific ASTM specifications and are commonly used for lifting. Look for proof-test certificates, manufacturer traceability markings, and clear grade and WLL embossing. Ask for written proof of testing and for any certificate of conformance before you accept the chain. These papers matter when you inspect, maintain, or certify your lifting gear.

Conclusion

Chains are available in various grades and different grades are suitable for different working conditions. Yuantai's lifting equipment is equipped with different grades of chains, which can be selected according to your needs.