How Do Brass Cable Glands Deal with the Thermal Expansion and Contraction of Cables?

In electrical systems, cables will experience thermal expansion and contraction due to changes in ambient temperature. Brass cable glands, as crucial components for cable connection and protection, possess various effective mechanisms and characteristics to deal with the thermal expansion and contraction of cables.
I. Advantages of Material Properties
Brass itself has good ductility and toughness. When cables expand due to heat, brass cable glands can, by virtue of the ductility of their material, stretch and deform moderately without being easily broken or damaged. Conversely, when cables contract due to cold, they can also contract to a certain extent without losing their sealing and fixing functions on the cables. This material property is like a "buffer zone", providing an adaptable space for the dimensional changes of cables during temperature changes, thus ensuring the stability and reliability of cable connections. For example, in outdoor power transmission lines where the temperature difference between day and night is large, brass cable glands can adapt to the expansion of cables during the high temperature in the day and adjust with the contraction of cables during the low temperature at night, keeping the cables in a safe and stable connected state all the time.
II. Rational Structural Design
Many brass cable glands adopt special structural designs to cope with thermal expansion and contraction. Some products are equipped with elastic compensation elements inside, such as springs or elastic rubber rings. When cables expand, these elastic elements will be compressed to absorb the extra length generated by the cable expansion; when cables contract, the elastic elements will release the stored energy to fill the gaps caused by the contraction, thereby ensuring that the cables are always in a tight and stable connected state and preventing cable loosening or poor contact due to thermal expansion and contraction. In addition, the threaded part of the gland is also carefully designed. The pitch and depth of the threads can allow for a slight axial displacement of the cables to a certain extent to adapt to the length changes brought about by thermal expansion and contraction, while still maintaining good sealing performance to effectively prevent the ingress of impurities such as moisture and dust into the cable connection points.
III. Assurance of Sealing Performance
During the process of cable thermal expansion and contraction, the sealing performance of brass cable glands is of vital importance. The sealing structure usually combines rubber sealing rings with the brass body. High-quality rubber sealing rings have good elasticity and weather resistance. They can always maintain a close fit with the cable surface during cable thermal expansion and contraction, preventing the intrusion of external substances. For example, in a high-temperature environment, the rubber sealing ring will not harden or lose its elasticity due to heat and can still effectively seal the cable; in a low-temperature environment, it will not become brittle and crack, thus continuously ensuring the sealing effect. Meanwhile, the brass body provides good support and fixation for the sealing ring, ensuring that the sealing ring will not shift or fall off when the cable dimension changes. The two work together to enable the brass cable glands to maintain a reliable sealing state while dealing with the thermal expansion and contraction of cables, ensuring the safe operation of the electrical system.
In conclusion, brass cable glands effectively cope with the thermal expansion and contraction of cables through their material properties, rational structural design, and reliable sealing performance assurance mechanisms. They play an indispensable role in various electrical systems, laying a solid foundation for the stable transmission of electricity and the safe operation of equipment.