Cable glands are strongly associated with the cabling process and harnessing solutions. Therefore, users need to get a grasp on how to select and install cable glands for each specific application.
1. Structure of cable glands
Structure of cable glands
Prior to the selection of cable glands, users shall have a notion of cable glands’ basic structure. Main components of cable glands include:
- The gland body is made from various materials such as plastic, brass, stainless steel. This component constitutes the outer sheath, ensuring the structural integrity and serving as a conduit for cables to pass through.
- Cap nut is basically made of the same materials as the main body, threads onto the body, and secures the cables in place. The design of the nut consists of a series of ridges or teeth that grip the outer shell of the cable, preventing the cable from slipping out. The threaded connection between the nut and body provides a secure cover for the cables inside.
- Moulded seal is made from elastic material such as rubber or silicon. The main function of this part is to create a tight sealing layer, preventing the penetration of moisture and dust. Depending on the level of protection required, the part can be made from materials that demonstrate enhanced characteristics in extreme temperatures and environments.
- Clamping seal insert plays the role of securing cables, alleviating the strain and preventing cables from being pulled or twisted.
- Entry thread: is the point where cables are inserted into the cable glands. The choice of thread size must be compatible with the diameter and types of cables used.
In some cable gland configurations, there might be additional locknut (extremely useful for moving applications), O-ring (enhancing the tight sealing ability).
2. Selection criteria for cable glands
In order to select appropriate cable glands, users should take into account the following criteria:
2.1 Determining the size of cable glands
The choice of cable gland sizes hinges on the overall diameter, armor diameter, and the cable’s thickness. With many options available, users may find it difficult to select cable gland size that corresponds to the cables being used.
The first tip is to always aim to use cable glands from the same manufacturer for the entire system, as this provides maximum efficiency and performance. Manufacturers often provide information stating any specifications or conversions needed to measure cable glands. This data will help you easily measure and determine the appropriate cable gland size
2.2 Environmental conditions
A crucial factor to consider when choosing cable glands is the environment in which they are occupied. If the cable glands are exposed to harsh weather conditions or other hazards, you will need a seal that can withstand these conditions. Additionally, if the cable glands are used in a hazardous area, you need ones that are designed to meet the relevant safety standards.
Besides, you need to consider the expected operating temperature and pressure conditions in your application. Different types of cable glands are designed to withstand different temperature ranges and pressure levels.
