Manhole Chains: Purpose, Types, and Selection Guide

[MikePhua]

Manholes are an essential part of modern infrastructure, providing access to underground utility systems, sewage lines, and stormwater drains. While they may seem like a simple component of the urban landscape, their covers and related mechanisms, such as manhole chains, are critical to the safety, functionality, and maintenance of these systems. Manhole chains are primarily used to handle the opening and closing of heavy manhole covers. In this article, we will explore the purpose of manhole chains, the different types available, their features, and the factors to consider when choosing the right one for your needs.
Purpose of Manhole Chains
Manhole chains serve a few key functions in construction and maintenance work. Their primary purpose is to facilitate the safe opening and closing of manhole covers. Manhole covers are heavy and difficult to handle manually, often requiring mechanical assistance or special tools to move. Without a proper chain system, workers would face significant risks in handling these covers, including back injuries, strains, or even accidents that could lead to severe injury or death.
The chains are often used in conjunction with a lifting device or hook, making it easier for maintenance teams to access underground utilities quickly and efficiently. They also help to secure the cover to prevent accidental displacement or removal, which could pose safety hazards in areas of high foot traffic or vehicular activity.
Types of Manhole Chains
There are various types of manhole chains, each designed for different applications. The choice of chain will depend on factors such as the weight of the cover, the type of environment in which the chain is used, and the specific safety requirements. Below are some common types of manhole chains:

1. Standard Manhole Chains
   These are the most commonly used type of chain for manhole covers. They are generally made from steel, designed to withstand heavy loads and resist corrosion. Standard chains typically consist of linked metal components, providing the necessary strength to lift and support the weight of the cover.
   
2. Retrievable Manhole Chains
   Retrievable manhole chains are designed to be easily retrieved after being used to lift a cover. These chains typically feature hooks or carabiners that allow for quick attachment and detachment from the cover. They are ideal for scenarios where the chain will need to be reused multiple times, such as routine maintenance on a municipal sewer system.
   
3. Hydraulic Manhole Chains
   Hydraulic manhole chains are equipped with a hydraulic lifting system. These chains are used when dealing with particularly heavy manhole covers or in situations where manual lifting is impractical. The hydraulic mechanism provides additional mechanical force, making it easier to lift and remove heavy covers without requiring significant physical effort.
   
4. Locking Manhole Chains
   These chains are designed with an added safety feature: a locking mechanism that prevents unauthorized individuals from opening the manhole cover. Locking chains are commonly used in high-security areas or locations where there is a risk of tampering, such as utility installations or hazardous materials access points.
   
5. Light-Duty Manhole Chains
   Light-duty manhole chains are used in areas where the manhole covers are relatively lightweight, and minimal lifting assistance is needed. These chains are often smaller in size, made from lighter materials like aluminum or coated steel, and are designed for low-frequency use.
   

Features to Consider When Choosing a Manhole Chain
When selecting a manhole chain for a particular application, it’s important to consider several key features to ensure safety, durability, and ease of use.

1. Material Quality
   The material of the chain is one of the most important factors in determining its strength and longevity. Steel chains are the most common because they provide the necessary strength to lift heavy covers and resist wear. Some chains are also coated with materials like galvanized or stainless steel to prevent corrosion and ensure a longer lifespan, especially in areas exposed to water or harsh weather conditions.
   
2. Chain Length
   The length of the chain is critical for ensuring the proper handling of the manhole cover. It needs to be long enough to reach from the cover to the operator but short enough to prevent excess slack that could cause a trip hazard or make the chain difficult to manage. Some chains are adjustable, allowing for flexibility in use depending on the size and depth of the manhole.
   
3. Weight Capacity
   Manhole chains must be rated for the weight of the covers they are designed to lift. Cover weights can vary significantly depending on the material and size, so choosing a chain that can handle the expected load is essential. Chains designed for larger covers typically feature heavier-duty links and stronger connectors to ensure they do not break under pressure.
   
4. Ease of Use
   A manhole chain should be easy to attach, detach, and manage. Some chains feature simple hooks or carabiners that allow for quick setup and removal. Chains with adjustable lengths and ergonomic designs can make the job easier for operators, reducing physical strain during repetitive use.
   
5. Safety Features
   Safety should always be a priority when selecting a manhole chain. Many chains come with built-in safety features like locking mechanisms or padded handles to prevent accidental releases. Additionally, reflective or high-visibility materials can help increase safety when working in low-light conditions.
   

Maintenance and Care of Manhole Chains
Manhole chains, like all heavy-duty equipment, require regular maintenance to ensure optimal performance and safety. Proper care can extend the life of the chain and prevent accidents caused by malfunctioning or worn-out parts. Here are some key maintenance practices:

1. Regular Inspections
   Periodically inspect the chain for signs of wear, rust, or damage. Check the links for any cracks, elongation, or bending that could reduce the chain’s load-bearing capacity. If the chain has a locking mechanism, ensure it is functioning properly and that the lock is not corroded.
   
2. Lubrication
   Apply appropriate lubrication to the chain, especially in the joints or moving parts. Lubrication helps reduce friction, prevent rust, and prolong the chain's lifespan. Be sure to use a lubricant suitable for the specific material of the chain (e.g., oil or grease).
   
3. Cleaning
   After each use, clean the chain to remove dirt, debris, or corrosive materials such as salt or chemicals. Proper cleaning prevents premature wear and helps identify potential issues before they become serious problems.
   
4. Storage
   Store the chain in a dry, clean environment when not in use. Avoid leaving it exposed to the elements, as moisture and dirt can accelerate rust and deterioration. Hanging the chain in a secure location can also help prevent it from tangling or becoming damaged.
   

Conclusion
Manhole chains are an essential tool for safely and efficiently lifting heavy manhole covers. With a variety of types and materials available, it's important to choose the right chain based on factors such as the weight of the cover, environmental conditions, and the frequency of use. Proper maintenance and care can ensure that the chain remains effective and safe for the long term.
As cities and infrastructure continue to evolve, the demand for reliable and durable manhole chains will remain high. Investing in high-quality chains, combined with regular maintenance, can help ensure that these critical access points are easily managed while maintaining safety standards for workers in the field.