Specific requirements of international safety standards for chain hoist manufacturers

Specific requirements of international safety standards for chain hoist manufacturers
In today's globalized industrial market, chain hoists, as important manual lifting tools, are widely used in construction, manufacturing, logistics, warehousing and other fields. For chain hoist manufacturers, meeting international safety standards is not only the key to ensuring product quality and user safety, but also an inevitable requirement for expanding the international market. The following are the specific requirements of international safety standards for chain hoist manufacturers:

1. Material and component requirements
Lifting chain: Most international standards require that lifting chains must be made of high-strength alloy steel and undergo heat treatment processes to enhance wear resistance and fatigue resistance. For example, the EN 13157 standard stipulates that the breaking load of the chain must be more than 4 times the rated load. In addition, the surface of the chain should be smooth, without defects such as cracks and sand holes, to ensure that it has sufficient strength and reliability during use. At the same time, the connecting ring of the chain must also meet specific requirements. For example, EN 13157 requires that the connecting ring of the hand chain should be able to withstand a force of at least 120 daN without plastic deformation.
Hook: The hook is the key load-bearing component of the chain hoist. It is usually made of high-strength steel. For example, the GB/T 7334-2016 standard stipulates that the hook material is 35CrMo, and it must undergo strict forging and heat treatment processes to ensure that it has good strength, toughness and fatigue resistance. The surface of the hook should be smooth, without sharp corners and burrs, and an anti-unhooking device should be installed at the hook mouth to prevent the heavy object from accidentally slipping off. At the same time, the shape and size of the hook must also meet the requirements of relevant standards to ensure that it cooperates well with the lifting chain and other components.
Brake: The brake is one of the most important safety components in the chain hoist. For example, the EN 13157 standard emphasizes the reliability of the pawl spring and requires manufacturers to increase the number of spring pawls as a redundant design during design to improve the safety and reliability of the brake. The ASME B30.16 standard requires that 1.25 times the rated load can be maintained in the braking state to meet the user's safety inspection habits. In addition, the friction pad of the brake should be made of asbestos-free material to reduce environmental pollution and harm to human health.
Other parts: such as gears, shafts, wall panels and other parts also have strict requirements. Taking the T/ZZB 0724-2018 standard as an example, the long shaft, spline hole gear, and four-tooth short shaft are 20CrMnTi; the yield strength of the left and right wall panels is 345 MPa, the tensile strength is 470 MPa, and the elongation after fracture is 20%. These requirements are to ensure the overall strength, rigidity and reliability of the hand chain hoist.

2. Design and manufacturing process requirements
Structural strength design: The hand chain hoist must have sufficient structural strength to withstand stress under various loads and working conditions. Manufacturers need to perform force analysis and strength verification according to relevant standards during design to ensure that the product will not fail under rated load and overload conditions. For example, EN 13157 stipulates that the tail end connection fixture of the chain should be able to withstand 4 times the rated lifting weight without breaking, and JB/T 7334-2016 requires that the hand chain hoist should withstand 2.5 times the rated lifting weight without damage.
Safety factor setting: In order to ensure the safe use of hand chain hoists, international standards require manufacturers to consider appropriate safety factors when designing. Generally, the safety factor of hand chain hoists is required to be between 3-5 times, which means that its actual load-bearing capacity should exceed 3-5 times the rated load. For example, in the test, hand chain hoists of 3T and below should be able to reliably support a static tensile load of 5 times the rated lifting weight and maintain it for 10 minutes; hand chain hoists of 3T and above should be able to reliably support a static tensile load of 4.5 times the rated lifting weight and maintain it for 10 minutes.
Manufacturing process control: Manufacturers should have advanced manufacturing processes and equipment to ensure the stability and consistency of product quality. For example, it should have automated lifting chain weaving machines, chain welding machines, continuous medium frequency quenching machines, test machines and other lifting chain manufacturing and testing equipment, as well as load limit debugging equipment, automated dynamic load performance test equipment and hand chain hoist assembly lines. At the same time, production should be carried out in strict accordance with the process flow, and strict quality control and inspection should be carried out on each production link to ensure the processing accuracy and assembly quality of parts.

3. Testing and inspection requirements
Static load test: The hand chain hoist needs to withstand a certain multiple of static load to test its structural strength and bearing capacity. For example, the GB/T 7334-2016 standard stipulates that the hand chain hoist should be able to reliably withstand a static tensile load of 3 times the rated lifting weight, and there should be no damage. During the test, the hand chain hoist is hung up and gradually loaded to the specified static load. It is kept for a period of time to observe whether it has abnormal conditions such as deformation and cracks.
Dynamic load test: It is used to evaluate the performance and reliability of the hand chain hoist under dynamic load. It is usually required that the hand chain hoist be lifted and lowered a certain number of times under the condition of bearing 1.1 times the rated load, such as lifting and lowering 2000 times continuously. During the test, check whether the lifting, lowering, braking and other functions of the hand chain hoist are normal, and whether the parts are loose or worn.
Fatigue test: Since the hand chain hoist is subjected to repeated loads during use, fatigue testing is required. For example, the ASME HST-2 standard has fatigue test requirements for rated load status, with a large number of tests, mainly focusing on the wear of components. Manufacturers should conduct fatigue tests in accordance with relevant standards to ensure that the product will not fail due to fatigue during long-term use.
Braking performance test: Braking performance is an important indicator of the safety performance of the hand chain hoist. During the test, the hand chain hoist is hoisted with the rated load, so that it is in a suspended state, and then the hand chain is released to observe whether the brake can brake quickly and reliably to prevent the heavy object from sliding down. At the same time, an overload braking test is also required. For example, the ASME B30.16 standard requires that 1.25 times the rated load can be maintained in the braking state to verify the performance of the brake under overload conditions.
Manual force test: EN 13157 and other standards have clear provisions for the manual force of the hand chain hoist. Manufacturers need to measure whether the pulling force required to operate the hand chain hoist is within the specified range under different rated lifting weights in accordance with the standard requirements. If the manual force is too small, the movement of the hand chain hoist may not be effectively controlled, posing a safety hazard; while if the manual force is too large, the labor intensity of the operator will increase and affect work efficiency. In addition, EN 13157 also specifically mentions that if the manual force is less than 20 daN, a protective device should be set to prevent misoperation.

4. Product certification and labeling requirements
Product certification: In order to enter the international market, hand chain hoist manufacturers usually need to obtain relevant international certifications. For example, the EU market requires products to pass CE certification to prove that they meet the EU's health, safety and environmental protection requirements. CE certification involves strict evaluation of the design, manufacture, and testing of chain hoists. In addition, the US market requires products to comply with OSHA and ASME standards and pass corresponding certifications, such as ASME B30.16 certification. These certifications are not only a passport for products to enter the international market, but also a commitment by manufacturers to product quality and safety performance.
Product identification: Manufacturers should set up clear and permanent signs in a conspicuous position on the chain hoist. The content of the sign should at least include product model and name, basic parameters (such as rated lifting weight, standard lifting height, etc.), factory number and manufacturing date, manufacturer name and trademark (if any), implementation standard number and other information. For example, GB/T 7334-2016 standard specifies the specific requirements and content of the sign. At the same time, the product packaging should also indicate relevant product information and safety precautions so that users can correctly operate and maintain the chain hoist during use and maintenance.

5. Quality Management System Requirements
ISO 9001:2015 Quality Management System: Hand chain hoists manufacturers must comply with ISO 9001:2015 quality management system standard requirements to ensure that the hand chain hoists produced have stable quality performance, reliable performance and excellent cost performance. The standard covers the quality management of the entire process from raw material procurement, production process control, product inspection to after-sales service. Manufacturers should establish a complete quality management system, clarify the responsibilities of each department and personnel, formulate strict quality control processes and documents, effectively monitor and manage each link in the production process, and continuously improve product quality and production efficiency.
Continuous improvement and quality improvement: Manufacturers should constantly pursue continuous improvement of quality, and continuously improve product performance, quality and safety by collecting customer feedback, analyzing market trends, and conducting technical research and development. For example, with the development of science and technology, some manufacturers have adopted advanced materials, design and manufacturing technologies, such as aviation aluminum alloy materials, lightweight design, intelligent control systems, etc., to make hand chain hoists safer, more efficient and convenient. At the same time, manufacturers should also strengthen employee training, improve employees' quality awareness and production skills, ensure that every employee can operate in strict accordance with the requirements of the quality management system, and provide strong guarantees for product quality.

6. Environmental protection and sustainable development requirements
Material environmental protection: In the selection of materials, manufacturers should give priority to environmentally friendly and recyclable materials to reduce pollution to the environment. For example, use asbestos-free friction plates, recyclable metal materials, etc. to reduce the impact of products on the environment during production, use and disposal.
Energy saving and emission reduction: Manufacturers should actively take energy-saving measures to reduce energy consumption and pollutant emissions during the production process. For example, optimize production processes and improve energy utilization efficiency; use environmentally friendly production equipment and coatings to reduce the generation of waste gas, waste water, and waste residue; strengthen the treatment and recycling of waste gas and waste water to ensure that emissions meet standards. At the same time, energy-saving factors should also be considered in the design and use of products, such as optimizing the structural design of hand chain hoists, reducing operating resistance, and improving work efficiency, thereby indirectly achieving energy savings.

In short, international safety standards put forward comprehensive and strict requirements for chain hoist manufacturers, covering materials, design, manufacturing, testing, certification, labeling, quality management and environmental protection. Only by strictly abiding by these standards and ensuring the reliability and stability of product quality and safety performance can manufacturers remain invincible in the fierce international market competition, win the trust and recognition of international wholesale buyers, and lay a solid foundation for the sustainable development of enterprises.