In the stamping industry, vertical expansion and contraction decoiling equipment, commonly known as decoilers, are extensively used for their affordability, high customization, and stability. A standard decoiler typically uses a hand-operated screw expansion method to tighten the coil by manually turning the handle in both counterclockwise and clockwise directions. However, this tightening method becomes difficult when the coil is too heavy (over 2 tons), or when it has a large expansion range or a wide width. In such cases, hydraulic expansion is required, and the decoiler that utilizes hydraulic expansion is known as a hydraulic decoiler.
However, traditional hydraulic decoilers use rotary oil cylinders with piston tails, which have three significant shortcomings in practical use. To address these issues, a new structure of the hydraulic decoiler’s rotary oil cylinder has been developed, which resolves the following issues:
Easy installation and dismantling of the rotary oil cylinder
The traditional hydraulic decoiler’s rotary oil cylinder has a piston positioning that is designed to allow for easy dismantling of the piston rod and piston. However, this design does not serve its purpose, as the rotary oil cylinder must still be completely dismantled for disassembly. The new rotary oil cylinder design features a lock groove in the rod cavity for the piston locking component’s installation and a groove for installing the sealing ring where the piston disk and the cylinder wall contact. This design simplifies the installation and dismantling of the rotary oil cylinder.
Enhanced load-bearing capacity
The piston diameter of the rotary oil cylinder used in the traditional hydraulic uncoiler is generally one-third larger than the piston rod, but its load-bearing capacity decreases when the piston rod diameter is limited. Moreover, the frequency of breaking at the tail end of the piston rod, which serves as the fixed ring’s half-ring installation groove, increases due to the axial force during the unloading process. The new rotary oil cylinder design eliminates the locking and positioning structural devices such as the half-ring installation groove, fixed ring, and stop ring. This design completely changes the phenomenon of the piston rod’s small diameter in the load-bearing area, greatly enhancing the piston rod’s load-bearing capacity.
Longer service life
The traditional hydraulic decoiler’s rotary oil cylinder has a piston rod’s diameter that cannot be arbitrarily changed due to the cylinder’s diameter limitation, and its service life is usually reduced to only nine months due to the frequency of piston rod tail breakage accidents. The new rotary oil cylinder design eliminates the existence of a positioning groove, achieving not only fast and accurate positioning but also significantly enhancing the rotary oil cylinder piston rod’s load-bearing capacity during stretching. This design extends the rotary oil cylinder’s service life to more than three times the existing rotary oil cylinder.
The new structure of the hydraulic decoiler’s rotary oil cylinder has resolved the significant issues of the traditional hydraulic decoiler’s rotary oil cylinder. The new design’s advantages mainly manifest in the piston positioning, load-bearing capacity, and service life of the rotary oil cylinder. The improved design enhances the hydraulic decoiler’s performance, ensuring more efficient and cost-effective operations in the stamping industry.