Why high-alloy material shearing machine blades need to be tempered multiple times: High-alloy blades that are quenched at high temperatures need to be tempered multiple times.  For example, medium-thick plate shears made of H13 (4Cr5MoSiV1) steel require more than two tempers. This is because these high-temperature quenched high-alloy steel blades contain more retained austenite after quenching. The purpose of multiple tempering is to allow the retained austenite to transform into martensite during tempering cooling, and the martensite formed from retained austenite then transforms into tempered martensite.  If a single long tempering is used, it is difficult to achieve the above structural transformations, resulting in insufficient tempering. This will lead to inconspicuous secondary hardening, poor dimensional stability of the workpiece, higher brittleness, and lower service life.  Licheng Knife is committed to popularizing industry knowledge for the wide audience of frontline sales professionals!

Reasons for the Poor Durability of H13 Shear Blades： In common heat treatment standards, technical requirements often specify only the hardness range. To reduce costs, outsourced heat treatment providers frequently focus solely on meeting this hardness requirement. During the heat treatment process, if the heating temperature or soaking time is insufficient, the alloying elements in the tool steel cannot fully dissolve into the austenite. This results in an inadequate quenched and tempered microstructure, leading to defects such as edge deformation (collapsing) and loss of shape during service. Solutions: 1.Conditioning Treatment: Subject the blade blanks to a preliminary quenching and tempering (conditioning) process to obtain an ideal pearlitic structure. 2.Graded Preheating: Implement multi-stage preheating and optimized soaking times to ensure the alloying elements are fully austenitized.

Shearing blades may suddenly develop cracks or break and fail during use. According to the type of damage, they can be divided into local damage (such as spalling, chipping, missing teeth, etc.) and overall damage, such as fragmentation, fracture, bulging, or splitting. A common characteristic is that most damage occurs at the parts of the blade that experience the greatest force, or in areas where stress is concentrated due to changes in the cross-section.  Based on the characteristics of the fracture process, it can be categorized into brittle fracture and fatigue fracture. Brittle fracture is mainly caused by metallurgical defects or process defects in the blade material, or overload due to improper operation; fatigue fracture is mainly caused by long-term use under cyclic stress and is commonly seen in the shearing of various medium and thick plates, as well as high-strength plates. Understanding the product and understanding the market are the keys to gaining the advantage!

Characteristics of H13 Material Shear Machine Blades： During the forging and heat treatment of H13 material, the surface is easily decarburized due to the influence of high-temperature heating. The drawback of surface decarburization is insufficient hardness. The deeper the decarburized layer, the greater the impact. The preventive measures are: firstly, to properly control the forging and heat treatment temperature; secondly, to apply paint or coating on the surface that requires hardness during heat treatment, in order to minimize decarburization as much as possible.

On May 1st, in this lush greenery and burgeoning early summer, we welcome the holiday that belongs to every worker.   Labor is the ladder of human civilization and progress. Whether it is a towering skyscraper, the sparks that light up the night, or every grain of rice on the dining table, all come from the hardworking hands of laborers. Among them are researchers tackling challenges in laboratories, delivery workers dashing through streets and alleys, and teachers quietly cultivating minds at the podium.   On this ordinary yet great day, we should not only praise the moments of creating miracles but also pay tribute to the ordinary figures who silently persist at their posts. Every profession deserves respect, and every drop of sweat deserves remembrance.   Salute to the laborers:   Because of you, the city’s development has vigorous momentum.   Because of you, the details of life are filled with warmth and convenience.   As we enjoy the holiday, let us extend our highest respect to all workers who contribute silently. May every effort yield a bountiful harvest, and may every dream blossom and bear fruit through hard work!

Issue: Uneven Quenching Hardness in Large-Scale H13 Shredder Blades Insufficient Machining Allowance: The forging allowance is too small, resulting in inadequate removal of the "black skin" (surface decarburization layer). Consequently, the carbon content in certain areas of the blade remains too low. High Loading Density: Excessive furnace loads lead to overly dense packing during quenching. This prevents uniform coolant circulation, resulting in inconsistent cooling rates across the blades. Overheating or Prolonged Isothermal Holding: Underheating or excessive holding times can lead to coarse grain structures. Conclusion: Under actual production conditions, the first two points are the primary causes of failure. Licheng Blades: Committed to Excellence in Professional Heat Treatment Processes.

Using DC53 (Cr8W2vSi) steel for shear blade ensures exceptional performance. When quenched at 1040°C and tempered at 520–530°C, it consistently maintains a hardness of HRC 62–63. This effectively overcomes the common issues found in Cr12MoV, such as insufficient hardness after high-temperature tempering and poor toughness. Key Advantages: Superior Machinability: Offers excellent cutting and grinding properties. Structural Integrity: Eliminates the risk of cracking during Wire EDM (Electrical Discharge Machining) processing. Dimensional Stability: After tempering, retained austenite is almost completely transformed, rendering cryogenic treatment virtually unnecessary. Optimized Microstructure: When tempered at a low temperature of 200°C, carbides are distributed uniformly without the presence of massive carbides, resulting in outstanding toughness. Choose Licheng for your blade needs! With our professional technical support, Licheng Knife provides you with the perfect solution for every application.

Hydraulic nuts are precision instruments, yet improper use can lead to equipment failure or safety hazards. Understanding these common misconceptions is vital for any maintenance team. Common Misconceptions "More Pressure is Always Better": Exceeding the maximum rated pressure can permanently deform the nut body or cause seal blowouts. Always adhere to the calculated pressure for your specific preload requirement. Neglecting Piston Stroke: Pumping beyond the maximum stroke limit can damage the internal stops or dislodge the piston. Always monitor the stroke indicator. Ignoring Thread Cleanliness: Thinking hydraulic power can "force through" dirty threads is a mistake. Debris can cause uneven loading or galling even under pure axial tension. Misalignment: Assuming the nut will self-correct on a tilted surface. Non-parallel mating surfaces create bending moments that stress the bolt and the nut’s seals. Skipping the Locking Ring: Relying solely on oil pressure for long-term holding. The hydraulic fluid is for tensioning only; the mechanical locking ring must be seated to maintain the load safely. Maintenance Recommendations Seal Inspection: Regularly check for weeping oil. Seals are wear parts; replace them at the first sign of degradation to prevent sudden pressure loss. Coupler Care: Keep quick-connect couplings capped when not in use. Even microscopic dust can contaminate the high-pressure pump system. Lubrication: Apply a thin layer of anti-seize or high-quality lubricant to the threads and the locking ring to ensure smooth mechanical operation. Storage: Store nuts in a dry, anti-corrosive environment. Moisture is the enemy of the precision-ground surfaces inside the pressure chamber. By avoiding these "easy" mistakes and following a strict maintenance schedule, you ensure that your hydraulic nuts remain a reliable asset for years to come.