Instrument trunking and its bends

To choose the right elbow for cable trays, you can take a look at the diagram below. Changhui Instruments: yunrun.com.cn http://yunrun.com.cn/upload/201603/31/201603312009076746.png. Installation of cable trays: yunrun.com.cn/tech/479.html. Cable trays are frequently used in industrial settings and building installations. They include slot-type trays, galvanized trays, ladder-type trays, stainless steel trays, and fiberglass-reinforced plastic trays. These trays are suitable for laying computer cables, communication cables, instrument cables, power cables, and various control cables. The experienced workers have summarized the following precautions for installing cable trays for reference by all construction workers: 1. When assembling the cable trays on site, make sure that the two sections of the tray are in a straight line. When installing cable trays in a factory building, attention should be paid to the distance from the ceiling, ensuring there is sufficient operating space. 2. When the cable tray makes a right-angle turn, the minimum bending radius must be greater than or equal to 10 times the outer diameter of the thickest cable inside the tray; otherwise, it will be difficult to handle this thickest cable properly. Right-angled elbows for cable trays are selected as part of the design; therefore, installers need to consider during the drawing review whether the bending radius of the chosen elbow tray is large enough. If not, the width of the tray must be increased. It is clear that the choice of tray depends not only on the amount of cables but also on their thickness. 3. Gas welding shall not be used for opening cable trays; mechanical methods should be employed instead. There are now specialized electric or hydraulic hole openers available. After placing the wire conduit in the cable tray, it should be secured with an appropriate gland or locking nut. 4. The drainage holes in the cable tray must remain unobstructed. 5. When the straight-line distance of the cable tray exceeds 50m, heat expansion measures must be taken. 6. As per the design, cable trays are usually installed on pipe racks or the racks of process pipelines. The cable tray should be installed above or beside the process pipes, and not below them. http://yunrun.com.cn/upload/201603/31/201603312009558685.jpg 7. Support spacing for instrument cable trays: The support spacing of XQJ-type cable trays on the installation should be less than the maximum allowable load span. 8. Tray width: Considering the number of cables, it is necessary to select a tray width with some margin to facilitate the addition of more cables in the future. Considering the right-angle bends of the thickest cables, the bending radius of the selected tray should be more than 10 times the outer diameter of the largest cable. 9. Separate laying of power cables and instrumentation cables within the cable tray: In a certain section, when the number of power cables and instrumentation control cables is relatively small compared to the capacity of the cable tray, they can be placed in the same tray, but they must be separated from each other. 10. Cable fixation within the cable tray: Cables running horizontally should be fixed every 2 meters, while cables running vertically should be fixed every 1.5 meters. 11. Grounding of metal cable trays: Metal cable trays used for instruments must be reliably grounded. Cable trays at regular intervals should be grounded every 30-50 meters. http://yunrun.com.cn/upload/201603/31/201603312010400168.jpg

Vertical convex elbow, vertical concave elbow

Then it’s simple enough for the person in charge of installation to do it themselves.

Thank you all for your valuable suggestions, :)