Grade 100 load chain breaking strength
G100 chain is EN818-2 standard lifting chain, it can be used with rigging for lifting, pulling and binding, mostly used in port transportation, factory lifting, bridge construction, industrial and mining, and other places with high strength requirements, the chain is tested under 2.5 times working tension, the breaking tension is four times of the working tension, and the performance is upgraded 25% compared with the G80 grade chain. Surface treatments are: polished, blackened, painted, electro-galvanized, hot-dip galvanized, sprayed, electrophoresis and so on.
In other words, the breaking strength is 4 times of the rated load. Let's take 10mm or 3/8 inch G100 grade chain as an example:
1. Analysis of chain specifications
3/8: It means that the link width of the chain is 3/8 inch (about 9.53 mm). This is one of the standards for chain size.
Grade 100: It refers to the load-bearing grade or strength grade of the chain, which is usually categorized according to the maximum working load of the chain. In Class 100 chain, “100” stands for its maximum load carrying capacity or breaking strength grade under standard test conditions. 2.
More Specifications：Grade 100 Chain Size
2. Definition of breaking strength of chain
The breaking strength of a chain is the maximum bearing capacity of a chain to reach rupture under ultimate load. This is usually tested by a standardized tensile test, i.e. the chain is stretched under horizontal tension until the chain appears to break or is unable to withstand more load. This test value is usually expressed in **Kilograms (kg) or Newtons (N)**.
3. Breaking Strength of Grade 3/8 100 Chain
For 3/8 Grade 100 chain, the ultimate safe working load is 4.0KN, the test load is 98.1KN, and the minimum breaking test load is 157KN, depending on the manufacturing process of the chain and the materials used. Different manufacturers may have different standards and specifications, but our test data is strictly in accordance with the production standard EN818, and even the parameters can be higher than the standard.
When choosing chain, we can do some judgment from the appearance besides looking at the breaking strength:Heavy duty chain quality inspection and judgment method
4. Factors affecting the breaking strength of Grade 3/8 100 chains
4.1 Link Chain material
The material directly affects the breaking strength of the chain, we adopt high strength alloy steel 25MnV & 8620 (material report available) for Grade 100, the tensile strength and toughness of the material will decide how much load the chain can bear.
20Mn2 has medium strength, high plasticity in cold deformation, good low temperature performance, superb weldability and machinability. Compared with carbon steel, its hardenability is high. This type of steel, due to the appropriate hardenability, has a high tensile strength.
20Mn2 chemical composition
C% | Mn% | Si% | S% | Cr% | Ni% | P% | Cu% |
0.17~0.24 | 1.40~1.80 | 0.17~0.37 | ≤0.025 | ≤0.30 | ≤0.30 | ≤0.025 | ≤0.25 |
20Mn2 mechanical properties
Tensile strength | Elongation % | Section shrinkage % | Yield limit | Impact absorption | Hardness |
≥785MPa | 10 | 40 | 590MPa | 47Aku2/J | 187HB |
25MnV is an alloy steel containing 2.5% manganese and vanadium.
25MnV chemical composition
C% | Mn% | Si% | Cr% | Ni% | P% | Cu% | Mo% |
0.18~0.23 | 0.70～0.90 | 0.15～0.35 | 0.40～0.60 | 0.40～0.70 | ≤0.035 | ≤0.030 | 0.15～0.25 |
25MnV mechanical properties
Tensile strength | Elongation % | Section shrinkage % | Yield limit | Impact absorption | Hardness | Strike toughness value |
≥980MPa | ≥9 | ≥40 | ≥785MPa | ≥47Aku2/J | ≤197HB | ≥59 J/cm2 |
4.2 Chain heat treatment process
The heat treatment process of lifting chains (such as quenching and tempering) is crucial to enhancing their strength. Through reasonable heat treatment, the hardness and abrasion resistance of the chain will be improved, so as to increase its breaking strength.
4.3 Chain design
The design of the chain, including the size of the links, the matching precision, the quality of rolling parts, etc., will affect its breaking strength. The rationality of the design can effectively disperse the load and improve the overall bearing capacity of the chain.
4.4 Lubrication and maintenance
Proper lubrication can reduce the internal friction of the chain, prevent wear and fatigue damage, and then improve the breaking strength of the chain. Regular maintenance and inspection can ensure the long-term stability of the chain in the process of using.
4.5 Working environment
The working environment of the chain will also affect its breaking strength. Under bad environment, such as high temperature, humidity, corrosive medium or extreme vibration, etc., it will accelerate the aging or breakage of the chain, which will reduce its breaking strength.
