Introduction to Tightening Methods for Hammer Heads of Impact Crusher Wear-Resistant Accessories
Impact crushers are widely used in crushing materials such as river pebbles, granite, basalt, iron ore, limestone, and quartz stone. The hammer head, a wear-resistant accessory of an impact crusher, is a core wear-resistant component. Because the hammer head primarily performs material crushing in an impact crusher, its design should meet the requirements of reliable operation, easy assembly and disassembly, and high metal utilization. Impact crusher hammer heads are typically made of high-chromium cast iron, high-manganese steel, and other wear-resistant alloy steels. They come in a variety of shapes, generally closely related to the tightening method and workload, with long, strip-shaped hammers being the most common. During operation, the hammer head of an impact crusher primarily impacts the material at high speed, directly contacting the material and rotating at high speed driven by the rotor. This makes it prone to loosening and requires frequent tightening. This article details its tightening methods.
1. Impact Crusher Blow Hammer Insert Fastening Method
The blow hammer is inserted into the rotor groove from the side, secured at both ends with pressure plates to prevent axial movement. The elimination of fastening bolts improves blow hammer reliability. This self-locking mechanism utilizes the centrifugal force generated by the hammer's rotation and the reaction force from impact crushing. Parts of the rotor susceptible to wear are designed with a replaceable design, making assembly and disassembly simple and easy to manufacture. This method has a low metal utilization rate, but the improved insert fastening method utilizes slotted blow hammers with longitudinal grooves on the hammer face, significantly reducing metal consumption. The working surface can be replaced four times, effectively extending the blow hammer's service life.
2. Impact Crusher Blow Hammer Wedge Fastening Method
This method primarily secures the blow hammer by inserting wedges into the corresponding slots between the blow hammer and the rotor. The wedge fastening method is more reliable and easier to install and remove. By eliminating relative movement between the blow hammer and the rotor, rotor wear is reduced. This method can significantly reduce wear between the blow bars and the rotor, but may result in lower metal utilization.
3. Bolt Tightening Method for Impact Crusher Wear-Resistant Components of the Blow Bars
In this method, the blow bars are bolted to the blow bar seat of the rotor. The blow bar seat features a tenon-shaped design, which allows the tenon to withstand the impact force of the blow bars during operation, preventing shearing on the bolts and improving the reliability of the bolt connection. Bolt tightening must be performed in two steps. The first step is initial tightening. Initial tightening should be performed to 60% to 80% of the bolt's standard axial force. The initial torque should not be less than 30% of the final torque. The second step is final tightening. For shear-type high-strength bolts, the shear-type clip should be removed during final tightening. To ensure uniform force distribution across all bolts in the bolt group, initial and final tightening should be performed in a specific order.
In addition to the above tightening methods, using high-quality materials for the blow bars can reduce wear and loosening. Regularly check the tightening to prevent loosening that can lead to equipment malfunctions.
ZHENGZHOU YIHONG INDUSTRIAL EQUIPMENT CO., LTD. is a trusted international supplier of crushing equipment and wear parts. We provide high-performance jaw crushers and cone crushers, designed with a deep understanding of global crushing technology. Furthermore, we specialize in supplying a comprehensive range of premium OEM-compatible wear parts for major brands including Metso, Sandvik, and others, ensuring our clients achieve maximum productivity and cost-efficiency.
