As the steel industry grows and users demand higher-quality steel, the requirements for rolling mills are steadily increasing as well. Short-stress-line rolling mill It boasts advantages such as high rigidity, superior product precision, lightweight equipment, and simple operation—particularly its unique feature of "rapid, in-line roll replacement." This makes it ideal for rolling operations on bar and wire rod mills. Short-stress-line rolling mill They can be broadly categorized into rack-mounted and rack-style types.
Short-stress-line rolling mill Work style:
The rolling force acting on the mill forms a closed loop—known as stress lines—that propagate through the internal stresses of key load-bearing components, including the rolls, roll bearings, housing, copper nuts, and tie rods. Meanwhile, the mill base and the lowering mechanism remain unaffected by the rolling forces, resulting in shorter stress lines compared to conventional mills. This design enhances the mill's structural strength while significantly reducing elastic deformation, which is why it’s referred to as a "… Short-stress-line rolling mill ”。
In addition to the "burning" of rolling mill bearings, other common incidents occur in the assembly of tie rods and rolls:
1. Axial movement. Causes: Failure of the tie rod positioning device; clearance between the thrust bearing cap and the bearing exceeding 0.2 mm; thrust bearing wear exceeding 0.2 mm.
2. The mill experiences significant "rebound." Causes include: failure of the hydraulic balance cylinder (or imbalance issues); wear on the ring, pressure ring, and end cap; as well as wear in the copper nut and excessive clearance in the bearing, among other factors.
3. Abnormal lever movement. Possible causes: The copper bushing in the frame has come loose; the position of the copper nut has been altered; one of the upper and lower roller shafts is at an angle; the tie rod seal has failed, allowing scale to enter; or the screw on the copper nut is damaged.
4. Rack copper sleeve detachment: Affects the reducer output shaft; causes copper sleeve wear; alters the relative positioning of the tie rod, housing, and frame; leads to loosening of fastening bolts.
Base Structure: The mill's tie rods are secured to the base via an intermediate frame, which in turn holds both the tie rods and the housing in place. The primary function of this setup is to anchor the mill base firmly onto the rolling line using four locking hydraulic cylinders mounted directly to the foundation. Notably, the mill stand itself remains unaffected by the rolling forces—instead, it is only subjected to overturning moments. Meanwhile, essential working fluids such as oil, water, and compressed air required for the rolling process are delivered to various mill components through quick-connect plates that facilitate seamless fluid and gas supply. In this section of the mill base, there are two critical aspects that demand special attention. First, the pin holes—not only serve as the connection point between the mill and the gearbox’s output shaft but also act as a safety feature, making regular inspection and maintenance crucial. Second, the quick-connect plates themselves require frequent checks of all their fittings. If any wear or damage is detected, these components should be replaced promptly to prevent leaks of oil, water, or air, which could lead to serious operational issues or even hazardous situations.
