Injection lock module size
As a core component of the injection molding machine’s clamping system, the injection molding lock module’s dimensional design is directly related to the stability of mold locking, the safety of injection molding production, and the quality of the molded parts. The lock module’s primary function is to provide sufficient clamping force during the injection molding process to prevent the mold from opening due to melt pressure within the cavity, thereby avoiding defects such as flash and mold bulging. Therefore, the rationality of the lock module’s size not only affects the efficiency of the injection molding machine but also has a crucial impact on the safety of the production process. For example, in the production of large plastic parts, if the lock module is too small, it may not provide sufficient clamping force, causing the mold to deform under high pressure and even causing equipment failure. On the other hand, if it is too large, the manufacturing cost and energy consumption of the equipment will increase, reducing the economic efficiency of production.
Determining the size of the locking module requires comprehensive consideration of multiple factors, including the injection molding machine’s clamping force, the mold’s size and weight, and the mold pressure of the plastic part. Clamping force is the primary parameter determining the size of the locking module. The greater the clamping force, the larger the required locking module to ensure structural strength and load-bearing capacity. The mold’s size and weight influence the locking module’s installation dimensions and support area. Large molds require larger locking modules to provide stable support and prevent mold shifting or shaking during the mold closing process. Furthermore, the mold pressure of the plastic part is a key consideration. Plastic parts with higher molding pressures (such as structural parts made of engineering plastics) generate greater reaction forces on the locking module, necessitating a larger locking module to resist these forces and ensure a stable mold closing state. For example, for parts with molding pressures exceeding 150 MPa, the thickness and width of the locking module typically need to be 10%-20% larger than those for standard parts.
The key dimensional parameters of the locking module include length, width, thickness, and the position and size of the mounting holes. The design of these parameters must meet the strength and rigidity requirements of the mechanical design. The length and width are mainly determined according to the installation dimensions of the mold and the distribution of the clamping force to ensure that the locking module can completely cover the force-bearing area of the mold and evenly distribute the clamping force. The thickness directly affects the load-bearing capacity of the locking module. Insufficient thickness will cause the locking module to bend and deform when subjected to force, affecting the clamping accuracy; excessive thickness will increase unnecessary material consumption and equipment weight. The position and size of the mounting holes need to match the clamping mechanism of the mold and the injection molding machine to ensure the reliability of the connection and the convenience of disassembly and assembly. For example, the diameter of the mounting hole is usually 0.5-1mm larger than the diameter of the connecting bolt to avoid assembly difficulties due to processing errors and to prevent shear damage to the bolts when subjected to force.
The design of the lock module size also needs to consider the mechanical properties of the material. Differences in strength, hardness, and toughness between materials will affect the size of the lock module. Common lock module materials include 45 steel and alloy structural steel (such as 40Cr). These materials have high strength and wear resistance after tempering. For lock modules with high strength requirements, alloy structural steel is usually used. In this case, the size can be appropriately reduced without reducing its load-bearing capacity. For lock modules with moderate strength requirements, 45 steel is more economical, but the size may need to be increased to meet the strength requirements. For example, the thickness of a lock module made of 40Cr steel can be reduced by 5%-10% compared to a 45 steel lock module, while still maintaining the same clamping force load-bearing capacity.
Precision control of the locking module’s dimensions is also crucial to ensuring its performance. Excessive machining errors can affect the accuracy and stability of mold clamping. During machining, the flatness, verticality, and positional accuracy of the mounting holes of the locking module all need to be strictly controlled. The flatness error is typically required to be no more than 0.05 mm/m to ensure a close fit between the locking module and the mold and avoid uneven force. Verticality errors can cause additional torque to be generated when the locking module is subjected to force, accelerating wear and fatigue damage to the components. Furthermore, the surface roughness of the locking module must be controlled within a certain range (usually Ra ≤ 1.6 μm) to reduce frictional resistance on the contact surface with the mold and lower energy consumption during the mold closing process. With the advancement of machining technology, the use of high-precision CNC machine tools for machining locking modules can effectively improve dimensional accuracy and surface quality, ensuring the stable operation of the clamping system.
