The support system of the pay off rack is the core structure that ensures stable load-bearing, flexible adjustment, and safe construction of equipment. Its design needs to take into account strength, rigidity, and adaptability. The following analysis is conducted from three aspects: structural composition, functional characteristics, and typical applications:
1、 Structural composition: Multi type support framework adapted to different scenarios
Frame material and connection method
Angle steel welded frame: commonly used in simple adjustable pay off racks, the central frame is formed by welding angle steel, and multiple support rods (such as steel pipes) are radially welded around the periphery. The number of support rods is usually 6 or more. This structure can be made on-site using construction waste, with low cost and easy disassembly, suitable for temporary construction scenarios.
High strength steel frame: used to carry heavy-duty wire reels (such as models with rated loads of 30KN-100KN), using 45 steel quenching and tempering heat treatment (quenching+high temperature tempering) to enhance strength, plasticity, and toughness, ensuring long-term use without deformation. For example, the frame of a horizontal tension pay off rack needs to withstand the dynamic load during the automatic rotation of the spool, and the uniformity of steel density is crucial.
Modular connection design: Some pay off racks are connected to support rods and connecting rods through steel fasteners, forming a steel strand winding frame. When the inner diameter of the spool changes, simply adjust the position of the connecting rod to adapt. For example, switching from a 2.6-meter spool to a 1.6-meter spool does not require replacing the overall frame.
Design of support rod and blocking part
The distance from the free end of the support rod to the fastener forms a natural barrier to prevent steel strands or cables from slipping out of the pay off rack. For example, in a hexagonal pay off bracket, the six equally divided rolling disc is fixed by a support rod. When the wire disc rotates, the blocking part ensures that the wire is stably laid out, avoiding the risk of detachment.
Some models use extendable support rods, which can be adjusted in height through hydraulic or mechanical lifting devices to meet different construction height requirements. The bottom of the trapezoidal cable laying rack is equipped with casters, and the height of the support rod can be freely raised and lowered for easy movement and positioning.

2、 Functional features: Balancing stable load-bearing and flexible adjustment
High load-bearing capacity
The supporting system needs to match the diameter of the wiring panel (600mm-4500mm) and tonnage (3T-20T or above). For example, a single set of triangular brackets with lifting cylinders can support a maximum weight of 19.5 tons and can be positioned within a height range of 1800mm-2400mm, meeting the needs of large, medium, and small cable reels.
The spool shaft is made of high-strength hollow round steel (such as O160 specification), with fixed end bearings and sliding bearings designed on the shaft, consisting of two sets of roller bearings, ensuring high load-bearing capacity and adapting to different spool widths.
Dynamic stability optimization
In high-speed rotating scenarios such as twisting cages, the support system needs to resist centrifugal force interference. For example, the old cable tray is positioned through flange shafts and bearings, but it is prone to strong lateral forces caused by the rotation of the spool, resulting in unstable support systems. After improving the design, a double lifting device or magnetic quick release structure is adopted to enhance the rigidity of the frame and ensure that the support system does not shake during the revolution of the wire reel.
The horizontal pay off rack is driven by a hydraulic system to automatically rotate the spool, and the support frame needs to withstand the rotational torque. Typical products such as the SF-308 model have a rated load of 50KN and a maximum spool diameter of 2.6 meters. Its support system uses hydraulic pre lift function to maintain the frame level during loading and unloading of the spool, avoiding tilting.
Security protection mechanism
The support system integrates a brake system to prevent accidental sliding of the spool. For example, a shaft type pay off rack is securely locked by a bearing pressure plate, and the wire reel shaft is automatically fixed by a torsion spring locking mechanism after installation to prevent axial sliding; The shaftless pay off rack adopts an electromagnetic brake motor, which automatically stops when the wire is disconnected to avoid equipment damage.
Some models are coated with anti slip coating on the surface of the support rod, or rubber gaskets are added to reduce the friction loss between the wire reel and the frame, and extend the service life.

3、 Typical application: Supporting the system to adapt to diverse construction needs
High altitude wiring in power engineering
The horizontal pay off rack supports large wire reels (such as those with a diameter of 3 meters or more), which are driven to rotate by a traction machine. The support system needs to withstand wire tension (up to several tons) and rotational torque. For example, the HY016-10 model has a rated load of 100KN and is suitable for reel diameters ≤ 2700mm. Its support frame is welded with thickened steel plates to ensure stability during high-altitude operations.
Fiber optic laying in communication engineering
The vertical tension pay off rack is used for multi head copper wire strands, and the support system requires precise control of the pay off tension (adjusted by air pressure). For example, the size of the Xianglong vertical tension pay off reel is an outer diameter of 250mm x outer width of 200mm x inner diameter of 100mm, with a wire diameter of 0.16-0.25mm. The support frame transmits signals to the frequency converter through displacement sensors to adjust the pay off speed in real time and avoid fiber optic micro bending losses.
Temporary wiring at construction sites
The simple adjustable pay off rack is connected to the support rod through steel fasteners to adapt to different specifications of steel strand coils. For example, in narrow construction sites, the support rod can be retracted to the minimum height (such as 800mm) to facilitate manual traction and laying out; In open spaces, it can be extended to a maximum height (such as 2400mm) to match large wire reels.