详情描述

(1) The conductor is a flexible stranded structure, which necessitates shifting the communication from the reliability of cable usage to the round, compact conductor. The flexibility of the stranded structure can easily damage mica tape, and mica tape is not suitable for use as the conductor in fire-resistant cables. However, some manufacturers believe that manufacturers should meet the user's requirements for the type of fire-resistant cable they need. I think the users do not fully understand the relevant details of the cable. Cables are closely related to human life, so cable manufacturers must clearly explain the relevant technical issues to the users.

(2) The sector-shaped conductors are also not suitable due to the uneven pressure distribution of the mica tape winding on the sector-shaped conductors, (65133). As shown in the figure, it can be observed that the pressure at the three sector angles of the sector core mica tape is high. Since mica is a lamellar silicate polymer, the interlayer molecular attraction is much weaker than the bonding force of the s1-0 covalent bonds in the crystal. The layers are prone to sliding, bonded with silicone, but the bonding strength is also low. When subjected to external scraping and squeezing forces, they are easily peeled off and cracked, especially when using a sector structure. When the winding core passes through the guide wheel, the branching rod, and the routing to the side edge of the work wheel, subsequent process compression of the insulation into the core is prone to scraping and abrasion, leading to a decrease in electrical performance. Additionally, from a cost perspective, the circumference of the cross-section of the sector-shaped conductor structure is greater than that of the circular conductor structure. Moreover, the addition of mica tape, which is a valuable material. Although the outer diameter of the cable with a circular structure increases, and the amount of polyurethane sheath material increases, the circular structure cable still saves on overall costs when compared to the total cost of the product materials. Based on the above description, from both a technical and economic standpoint, the circular structure is the conductor for fire-resistant power cables.

(3) There are three types of mica: synthetic mica, muscovite, and phlogopite. The quality and performance of muscovite and phlogopite are good, while that of phlogopite is poor. For small cables, it is necessary to choose synthetic mica tape for winding. Laminating with mica tape is not allowed. Mica tape absorbs moisture easily over time. Therefore, when storing mica tape, the temperature and humidity of the surrounding environment must be considered.


(2) Flame-retardant cables are primarily used for the power supply circuits of emergency power sources, which are required to operate normally during a fire. Due to the sharp rise in environmental temperature during a fire, to ensure the transmission capacity of the circuit and reduce voltage drop, for circuits with longer power supply lines and strict voltage drop limits, the cross-sectional area of the flame-retardant cable should be at least increased by one grade.

That covers the main applications and installation precautions for refractory cables. Did you get all that? Shanghai Qiyue High-Temperature Cable Co., Ltd. specializes in stable-phase cables, ultra-soft cables, semi-soft cables, semi-rigid cables, special cables, microwave waveguides, and devices. With years of production experience in the cable industry, we boast advanced production technology and experienced engineers, and our products are highly regarded in the field. We can customize various special cable assemblies and waveguide components to meet the unique needs of different clients.