Spare Parts I 2022-11-29 22:14:15

Lifting Chain & Load Chain of Hoist and Cranes Overview

Hoist and crane loading chain overview on Galvanized chain, Manganese steel chain / G80 hoist chain, Explosion-proof chain, stainless steel hoisting chain.

The lifting chain of electric chain hoist adopts Φ7.1mm and Φ12mm grade 80 surface hardening lifting chain to ensure its safety and durability. The strong hardened surface of the hoisting chain prevents chain breakage and softening of the core material, so that the hoisting chain maintains high performance for a long time.

Loading chains

The chain of the electric chain hoist is made of low carbon alloy steel, which makes the liftingchain more tough, stronger and wear-resistant, ensuring safety during work. Because of the specific working strength and characteristics of the hoisting chain, the tensile strength, fatigue strength, toughness and wear resistance of the chain are very important for the high-speed meshing of the chain on the sprocket and frequent operations with dynamic loads. The material used for the chain remainsshould remainductile even when quenched (case hardened), and an alloy steel suitable for formability, weldability, and resource saving must be developed. In addition, in order to ensure the balanced quality of the chain, safe use and time-effectiveness, allthe electric chain hoistshave been tested for5 to 2 times the tensile force before leaving the factory. To ensure the safe use of users.

The load chain of the electric chain hoist can also be lengthened and customized according to the requirements of customers, making it more convenient and worry-free for you to use. The loading chains of imported electric hoists are equipped with chain bags, which make the electric chain hoist look clean, tidy and beautiful. The chain bag is also equipped with anti-rust oil so that the hoisting chain is not easy to rust, thus prolonging the service life of the electric hoist.

Types of loading chains for your selections based on lifting requirements

Galvanized chain

Anti-corrosion and anti-rust
Enhanced adhesion and hardness

The formation process of the hot-dip galvanized layer of the galvanized chain is the process of forming an iron-zinc alloy between the iron matrix and the outermost pure zinc layer.Galvanized chains are divided into traction chains, transmission chains, special special chains, and conveyor chains according to different uses.

Manganese steel lifting chain

Anti-corrosion and anti-rust
Enhanced adhesion and hardness

The manganese steel lifting chain is made of high-quality alloy steel, the scientific name is 20mn2a, which is professionally manufactured.

Explosion-proof lifting chain

Beryllium Bronze Aluminum Bronze
Reduce hazards in flammable and explosive places

The explosion-proof chain is made of beryllium bronze and aluminum bronze alloy materials. The advantageof the explosion proof chainis that there is no sparkproducedwhen there is collisionhappens.

Stainless steel lifting chain

304 Chrome Nickel Stainless Steel
Thelifting chainis resistant to high temperature, corrosion, acid and alkali

Stainless steel chains are most suitable formaterial handlingoperations in places with corrosion resistance, chemical elements and large temperature differences, such as: food machinery cleaning, glass machinery return, etc. As a common transmission force device, the hyperbolic arc design is used to reduce friction. It is most suitable for places with high power and slow running speed.

Galvanized load chain

The appearance of the galvanized chain is cyan self-color. That's the result of passivation by bleaching of the chain's zinc coating. The zinc coating hardly changes in dry air. In moist air, in water containing carbon dioxide and oxygen, its surface will form a film mainly composed of basic zinc carbonate. This film has a corrosion inhibitory effect. It can prevent the metal from being corroded continuously. We have seen that some galvanized chains quickly turn from white to brown after use, but there is no greater change after this, and this is the reason.

Why should the lifting chain be galvanized? What is the role of chain galvanizing?

The galvanizing of the chain can play a role in isolation, preventing the chain from being oxidized in contact with the air, and prevent the chain from rust, which affects the performance of the chain.
Galvanized chain can prevent chain friction, increase chain wear resistance, improve operation safety and reduce chain damage.
Working in humid air, it is not easy to rust and prolong the use time.
Galvanized lifting chains are very useful, which can effectively reduce chain damage and prolong service time. Once the galvanized layer of the chain is damaged during the inspection process, it should be repaired in time to avoid greater damage to the chain.

Comparison of galvanized chains & Ordinary chains

The physical properties of ordinary chains and galvanized chains are the same, but their anti-corrosion properties are not exactly the same because of different surface coatings.

Ordinary chains generally refer to chrome-plated chains. Chromium is a silver self-ferrous metal. It is very stable in the atmosphere, and can even maintain a stable state in solutions of alkali, nitric acid, sulfide and carbonate. Chromium has a hard texture, strong wear resistance, and can maintain its luster for a long time. The disadvantage of chrome plating is that it does not reliably prevent rusting of the underlying metal. Therefore, it is also plated with copper or copper-tin alloy plating that can bond well with the underlying metal. In general, the chrome-plated chain has the characteristics of a slightly higher cost. Most of the domestic high-end cars and light vehicles are equipped with it, and it is generally not recommended to use it.

Compared with ordinary iron chains, galvanized chains have undergone special galvanizing treatment in production and processing, which shows more excellent characteristics in use, so that they have been improved in terms of product service life and actual use. The process of galvanizing is relatively simple and the cost is relatively low, so it is used for ordinary applications and special hazardous applications.

Storage of galvanized chain

Galvanized chain is a common lifting devices in material handling feild. The anti-corrosion properties of chains produced by different manufacturers are not completely the same. Although they have the advantages of anti-oxidation and anti-corrosion, they also need to pay attention to the storage environment, otherwise it will lead the galvanizing coating lose the anti-corrosion effect. What conditions should be required for the use of the galvanized chain?

The use of galvanized chain is to keep away from acidic substances with strong corrosive effect, and also to avoid the contamination of galvanized chain by viscous liquids such as oi. Sincezinc is relatively stable in contact with water, so if the galvanized chains usually do not corrode like iron chains in humid environmental conditions. Whereas the zinc is relatively active in acidic environmental conditions, it will react chemically withacidic elements, whichwill be harmful for galvanized chains.Therefore,the galvanized chain will be used in the supposed conditions to geta better use effect and prolong the service life.

How to do galvanized chain inspection?

In order to remove the gab of the entire chain, it is necessary to apply a certain degree of tension to the chain and measure it.
When measuring, in order to minimize the error, measure at the place of section 6-10 (link).
Measure the inner L1 and outer L2 dimensions between the rollers of the number of segments to obtain the judgment dimension L=(L1+L2)/
4. Find the elongation length of the chain. This value is compared with the limit value of the chain elongation in the previous item.
The elongation of the chain = judgment size - reference length / reference length * 100%.
Reference length = chain pitch * number of knots.

Visual inspection of galvanized chain:

Whether the inner/outer chain pieces are deformed, cracked or corroded.
Whether the pin is deformed or rotated or corroded.
Whether the roller is cracked, damaged or excessively worn.
Whether the joint is loose and deformed.
Whether there is abnormal noise or abnormal vibration during operation, and whether the chain lubrication condition is good.

Chain length accuracy measurement method:

The chain is cleaned before measurement.
Encircle the chain under test on the two sprockets, and the upper and lower sides of the chain under test should be supported.
The chain before measurement should stay for 1min under the state of applying 1/3 of the minimum ultimate tensile load.
When measuring, apply the specified measuring load on the chain to tension the upper and lower chains. The chain and sprocket should ensure normal tooth engagement.
Measure the center distance of the two sprockets.

Through the previous inspection and measurement, you can easily know all the data of the galvanized chain, which plays a great role in the maintenance and use of the galvanized chain.

Reasons of galvanized chain breaking

Whether it is an ordinary chain or a galvanized chain, if it is not properly maintained, there may be a lot of unnecessary troubles. How can these unnecessary troubles be eliminated?

The reasons for the breakage of galvanized chains can be simply summarized as follows:

Some items of sprocket and sprocket box do not meet the design requirements or standards.
The transmission chain may have quality problems.
The tensile load of the chain exceeds the predicted range, and the chain transmission speed, chain selection, and design problems in the chain transmission will all cause the breakage of the galvanized iron chain in use.
The most important influencing factors are the quality of the galvanized chain and the actual installation design.

The special zinc layer protection of the galvanized chain can make it extremely secure in the transmission of low-pressure fluids, but the fracture phenomenon during the transmission of the galvanized chain is also a headache for many users. Therefore, the breakage of the galvanized chain is not completely unpreventable. As long as you pay more attention to it, you can still reduce unnecessary troubles.

Stainless steel hoist chain

Stainless steel lifting chains are mainly used forhoisting,material handling, bundling and traction in metallurgy, machinery, ships, petrochemicals, fisheries, mining, construction, ports, forestry, light industry and other industries.The stainless steel hoisting chains can bear a variety of loads and variable loads, has a large bearing safety factor, good soft performance, safe and reliable use, light weight, easy to carry and transport.

Stainless steel hoisting chain has high tensile strength, fatigue strength and impact toughness. Under high-speed working conditions, it has good wear resistance, shock resistance and good running stability.With good corrosion resistance,the stainless steel hoist chainscan work normally in harsh environments with various harmful media.

How to protect and maintain the stainless steel lifting chain?

The stainless steel chain can adjust the length of the chain according to the lifting height of the loading object. It is an indispensable and important fetching equipment for the lifting crane. It plays an important role in improving the operation efficiency of the overhead crane and expanding the operation scale of the crane. So how to protect and maintain the stainless steel crane chain?

The sprocket should be installed on the shaft without skew and swing. The end faces of the two sprockets in the same transmission assembly should be located in the same plane. When the center distance of the sprockets is less than 0.5 meters, the allowable deviation is 1 mm. When the center distance of the sprockets is more than 0.5 meters, the allowable deviation is 2 mm. But it is not allowed to have the phenomenon of friction on the side of the sprocket teeth. If the two-wheel weaving is too large, it will easily cause off-chain and accelerate wear. It is necessary to carefully check and adjust the offset when replacing the sprockets.
The tightness of the lifting chain should be appropriate, too tight will increase power consumption, bearings will be easy to wear and too loose, and the chain will be easy to jump and de-chain. The tightness of the chain is: lifted or pressed from the middle of the chain, the center distance of the two sprockets is about 2%-3%.
If the new lifting chain is too long or stretched after use, it is difficult to adjust. You can remove the chain links according to the situation, but it must be an even number. The chain link should pass through the reverse side of the chain, the cleat should be inserted outside, and the opening of the cleat should be in the opposite direction of rotation.
After the sprocket is severely worn, the new sprocket and new chain should be replaced at the same time to ensure good meshing. You cannot just replace a new chain or a new sprocket on your own. Otherwise, the meshing will be bad and the wear of the new chain or the new sprocket will be accelerated. After the tooth surface of the sprocket is worn to a certain extent, it should be turned over and used in time (referring to the sprocket used with the adjustable surface). to extend the operating time.
The old hoisting chain cannot be mixed with some new chains, otherwise the impact will easily occur during the transmission and the chain will be broken.
The lifting chain should remember to add lubricating oil in time during work. The lubricating oil must enter the matching gap between the roller and the inner sleeve in order to improve the working conditions and reduce wear.

Comparisons of galvanized chain and stainless steel chain

According to different materials, there are many types of lifting chains, including manganese steel chains, stainless steel chains, galvanized chains and explosion-proof chains, etc. Each type of lifting chain has its own working environment, such as manganese steel chains are used for high-strength, large-tonnage lifting operations, explosion-proof chains are used in flammable and explosive places, and stainless steel chains are used in wet environments. Each chain has its own unique characteristics, but galvanized chains and stainless steel chains havethe samefeatures. How to select from the galvanized chains and stainless steel chains? Check the comparisions of both now.

Galvanized chain

Process features: Galvanized chain is the same as stainless steel chain, it has super anti-rust and corrosion resistance to the corrosion of alkali, moist air and others, etc.The galvanized chains is processed with a zinic coating to protect the hoisting chain from corrosion, which is different fromthe stainless steel chain.

Application environment: In some seriously polluted industrial areas or coastal cities, the environment is highly corrosive, so it is necessary to use galvanized chains withhighcorrosion resistance. The galvinzed chains also can be used inseawaterin which the stainless steel chains corrode easily.

Application : Galvanized chains can bemainly used in construction, light industry, automobile, agriculture, animal husbandry, fishery and commercial industries.

Stainless steel chains

Process features: stainless steel chains are made of nickel, chromium and other metal elements mixed into the metal to achieve anti-rust and anti-corrosion effects. Long-term use in harsh environments can keep the stainless steel bright and bright at all times. This is the characteristics of stainless steel chains.

Application environment: For relatively dry environments, stainless steel chains are generally usedwith good working life,both for indoor andoutdoor use. However,regulary maintanace is required to keep the outer appearance to be cleaned frequently.

Application conditions: Stainless steel is mainly used in the construction field, and it is one of the highest strength materials among the metal materials used in construction.

Although the two lifting chains have the same characteristics and can be shared in many environments, there is still a certaindifference between the two types. The galvanized chain is like wearing a mask andprotective clothing which are used to prevent the invasion of the virus, and the stainless steel chain is more like injecting itself with a vaccine, and it produces antibodies to resist the attack of the virus. This is the biggest difference between the two.

Both stainless steel chains and galvanized chains play a good role in lifting operations. From the perspective of cost performance, galvanized chains have more advantages, so there is no absolute difference between the two chains, so what choice should be made? ,Itis entirely up to you.

Manganese steel chain

Manganese steel is the basic material for the production of 80-level lifting chains. Manganese steel is the abbreviation, and the full name is 20Mn2A or 25MnV. These two materials are the most basic materials. Generally speaking, 20Mn2 is used as the basic material below 16mm, and 25MnV is used as the basic material above 16mm. The manganese steel lifting chain is different from the iron chain. Although there is not much difference in appearance, the difference in strength and toughness is very large.

Manganese steel lifting chains are generally synonymous with high strength. However, no matter how strong the metal is, it is difficult to resist the damage caused by rust or corrosion. Therefore, the biggest problem encountered in the use of manganese steel lifting chains is rust and corrosion. In order to deal with these problems, the manganese steel chain will be processed witha protective layer,formed on the surface of the chain toprevent rust and corrosion. In this way, the manganese steel chaincan be used ina humid environment and an acid-base environment.

The manganese steel lifting chain treated with blackening process not only takes into account the strength of the chain, but also has the ability to deal with humid environment and acid-base environment, which can help users to complete more and more complex lifting operations.

G80 lifting chain

When purchasing electricchain hoists,it is often heard that" Our chain hoists use G80 hoisting chains." And then what is G80 hoisting chains?

G80 lifting chain, the representative of manganese steel lifting chain, is an international standard high-strength lifting chain, not only G80 lifting chain, but also G100 lifting chain and the relatively rare G120 lifting chain. The biggest feature of the chain is its high strength and toughness.

G80 hoisting chain is mainly used for large-tonnage hoisting operations. Its safety factor is higher than that of ordinary hoisting chains, which is about 4.0. For hoisting chains of the same size, G80 hoisting chains have high load capacity. This is mainly due to a special metal element - manganese.

G80 lifting chainis thehigh-strength chain. High-quality alloy steel (manganese steel, etc.) materials are used, and the quality is strictly controlled throughout the whole process, so that the lifting chain can reach the 80-level international standard.

Standards of the lifting chain :

lifting chain safety guarantee: 4 times the safety factor and 4 times the test load.
Hoisting chain application: high precision calibration chain, hoisting chain.
Lifting chain manufacturing standards: ISO3077, EN818-2, AS232
Lifting chain strength grade: 80, 70, 60.
Lifting chain surface: polishing, blackening, dipping paint, hanging plastic, electroplating.
Lifting chain material: high quality alloy steel.

This is the G80 hoisting chain that is widely used in various industries. With its ultra-high strength, outstanding load capacity and safety factor.

Explosion proof hoisting chains

Lifting chains are vitalaccessories for electric chain hoist and manualchain hoists, and chain rigging. These tools are suitable for lifting in a variety of environments. There are a lot of flammable substances in some special work places, such as oil refineries, thermal power stations, flour mills and chemical plants. The impact of ordinary metal chains is likely to produce mechanical sparks,which may cause the combustion, fire and explosion tooccur. At this time, a lifting tool for explosion-proof chains is required.

The explosion-proof chain uses beryllium bronze and aluminum bronze as blanks. Due to the characteristics of the materials, there will be no mechanical fire caused by collision, thus avoiding the occurrence of explosion accidents in such environments.

Whenmaterial handlingoperations required in a flammable and explosive working environment, it is necessary to use an explosion-proof chain.

The explosion-proof chain is made of beryllium bronze and aluminum bronze alloy materials. The advantage is that there is no sparkproducedwhen there is collision.

Theexplosion-proof chain is suitable for petroleum, chemical, electronics, railway, shipbuilding, metallurgy, boiler, mining, gas production, power generation, storage and transportation, pharmaceutical, gas production and other environments with potential fire and explosion hazards.

Which do you choose, the maganese steel chains, stainless steel chains or galvanized chain?

Advantages of manganese steel chains

In terms of strength, the most popular lifting chain at present is the manganese steel lifting chain. Under the same specification, the manganese steel lifting chain has a stronger load capacity and can be competent for most of the large tonnage lifting operations. It belongs to the representative of high-strength lifting chain, and its super load capacity comes from manganese element.

Advantages of stainless steel chains

In terms of functionality, stainless steel hoisting chains have an irreplaceable position. Stainless steel hoisting chains mainly use nickel and chromium elements. These two elements have good rust resistance, so that they can be used in harsh environments. It can work in the middle without suffering from large corrosion. At the same time, it has a high degree of cleanliness, the surface is smooth and beautiful, and the cleaning and maintenance are easier and more convenient.

Advantages of galvanized chains

In terms of cost performance, galvanized hoisting chains are a good choice. The performance of galvanized hoisting chains is similar to that of stainless steel hoisting chains. It is galvanized on the surface, which still has a certain gap with the overall rust prevention of stainless steel. All said, its price is more advantageous than that of stainless steel lifting chains.

Each of the three lifting chains has its own advantages. Each type of lifting chain can shine in its own field of work. There is no absolute advantage or disadvantage, and everyone canselect based on the applicaiton environment and lifting requirements.

Four Ways to Reduce Wear on Lifting Chains

In addition to the deterioration of metal performance caused by the influence of individual environments, there are two human factors that will cause greater damage to the lifting chain. One is overloaded use, and the other is excessive wear. Overload operation is completely avoidable. , and the problem of wear and tear can also be alleviated bythe followingmeans.

Method 1: Make surethe tightness of the chain is appropriate. If the chain is too tight in the process of use, it will easily increase the power consumption, and if it is too loose, it is easy to skip the chain.
Method 2: The old and new chains cannot be mixed, the tolerance of the old chain is not as good as that of the new chain, which will inevitably increase the burden of the new chain in the operation process.
Method 3: Appropriately add lubricating oil when in use, thereby improving work efficiency and reducing the wear between chain rings.
Method 4 : Overload use will also increase the wear of the chain, and will lead to double damage of chain stretching and wear, so overload use should be avoided.

By adopting the above fourtips in the process of using the lifting chain can effectively alleviate the wear of the lifting chain

How to avoid damage to the lifting chain

Lifting chains are critical in the lifting industry. Lifting chains is a frequent used thing in life, but many people cause damage to the chain due to improper operations, which will reduce the chain's life. So, how should we do to reduce chain wear when using the lifting chain?
The user should use the chain in accordance with the operating specifications. It is prohibited to overload or pull heavy objects diagonally during the lifting process. This can help to extend the life of the chain by reducing wear.
The operator should pull the chain steadily when lifting heavy objects. Keep the chain from being pulled too hard. This is prone to chain jams and, in severe cases, breaks, resulting in the chain being scrapped and rendered unusable.
Maintenance of the chain is also very important, as it can reduce chain wear and tool loss, ensuring that the chain is durable and does not break.
The chain should be stored in a dry and ventilated environment to avoid it becoming damp and rusty and breaking during use.
To some extent, the aforementioned points can help to avoid chain damage. You must select the lifting chain that best meets your needs, but more importantly, everyone must standardize the operation.

Precautions for cleaning the electric chain hoist lifting chain

The length of the electric chain hoist lifting chain can be adjusted based on the height of the heavy object. It serves as a critical load-bearing device in lifting operations. It broadens the scope of work and increases productivity. Consider the precautions for cleaning the electric chain hoist lifting chain.

Do not use strong acid or strong alkaline cleaning agents, such as rust remover, for cleaning; these chemicals will cause serious damage or even breakage of the lifting chain.
Never clean the lifting chain with a chain washer containing solvent, as this may cause damage to the chain.
The use of scouring oil is also prohibited, as this cleaning method will remove the lubricating oil from the transmission part.
Wipe with a dry cloth, especially in rainy or humid conditions.
When necessary, you can clean the gaps between the chains with old toothbrushes and other tools.
If there is mud, sand, or dirt, you can complete the cleaning with a brush. Warm soapy water can be used to help clean if necessary.

Article by Bella ，who has been in the hoist and crane field since 2016. Bella provides overhead crane & gantry crane consultation services for clients who need a customized overhead travelling crane solution.Contact her to get free consultation.