Цепные блоки, также известный как цепные шкивы, are a type of lifting device that uses a chain to raise and lower loads. They provide mechanical advantage through a system of pulleys. When selecting and using chain blocks, it is important to consider the working load limits and safety factors to ensure safe and efficient lifting.
What Is A Safety Factor?
А chain hoist safety factor is the ratio of breaking strength to working load limit. It indicates the block’s maximum load capacity relative to its forces under normal operation. Safety factors are incorporated into chain block design to account for dynamic loads, ударные силы, wear and other unforeseen stresses.
Типичные коэффициенты безопасности для цепных блоков варьируются от 3 к 5. This means the block has 3 к 5 раз превышает номинальную емкость при нормальном использовании. Регулирующие органы, такие как OSHA, требуют минимального коэффициента безопасности 5 for most general purpose lifting equipment. Однако, specialized chain blocks can have lower safety factors depending on the application, такие как блок цепного шкива 20 тонна.
Chain Working Load Limit (ВЛЛ)
Предел рабочей нагрузки (ВЛЛ) refers to the maximum load a chain block is as designed to safely lift under normal operation. The WLL takes into account the safety factor incorporated into the block’s design and components. Цепные блоки обычно имеют определенный предел допустимой нагрузки, который значительно ниже их предельной прочности на разрыв..
Under normal usage, the sum of all loads acting on a chain block should not exceed its stated WLL. Перегрузка цепных блоков увеличивает риск выхода из строя компонентов и случайного освобождения груза.. Всегда сверяйтесь с маркировкой WLL или табличкой с техническими данными при выборе цепной цепи подходящего размера для конкретной подъемной задачи..
Factors That Impact Safety
Как профессионал производители подъемников, we are very responsible to tell you that there are several factors that affect the safety factor and WLL of the chain block:
- Pulley Size & Number – More/larger pulleys provide higher mechanical advantage but lower load capacity.
- Цепной класс – Higher grade chain with greater breaking strength allows for higher WLLs.
- Качество компонентов – Better material and construction techniques increase rated capacities.
- Сертификаты – Certified chain blocks by reputable standards organizations provide a defined WLL.
- Заявление – Specialized blocks for severe service have lower safety factors for cost efficiency.
Overview For The Safety Factors Of Chain Blocks
The safety factor and working load limit of chain blocks indicate their rated lifting capacity relative to their actual breaking strength. Safety factors of 3 к 5 times are common for general purpose chain blocks, providing a buffer for unforeseen loads and stresses.