The working principle of injection molding (also known as injection molding) machinery is very similar to that of a syringe. It uses the thrust of a screw (or plunger) to inject pre-plasticized molten plastic (i.e., viscous flow state) into a closed mold cavity, and obtains the product after solidification and shaping.
The industry commonly uses clamping force as a parameter to classify injection molding machines into large, medium, and small sizes. Clamping force refers to the locking force applied to the mold during injection to overcome the expansion force of the melt within the cavity on the mold. Clamping force is generally proportional to the volume of the finished product. In other words, the larger the finished product, the larger the injection molding machine required to manufacture it.
Risk Analysis of Large Injection Molding Machines
Injection molding machines are high-voltage, high-speed, and high-temperature devices, posing a significant risk; therefore, safety precautions must be taken very seriously. The main hazards posed by injection molding machines are concentrated in the mold clamping area, injection nozzle area, and material feeding area , potentially causing mechanical or thermal injuries to personnel on site. The plastics machinery industry was one of the first to introduce national standards, aimed at helping plastics machinery manufacturers better identify and assess risks, take appropriate measures to reduce risks and isolate hazards, and ultimately design and manufacture safe injection molding machines.
The working principle of large injection molding machines is similar to that of small and medium-sized injection molding machines. However, because large injection molding machines produce larger finished products, some functions have been upgraded / added. For example, in the mold change process, a fully automated carriage is used to handle mold changes to improve efficiency. In the material handling area, the injection molding machine and a robotic arm are combined to form an integrated injection molding unit with automatic material unloading function (click the link to learn about integrated manufacturing system safety), completing the unloading of large finished products. The introduction of fully automated carriages and robotic arms increases the possibility of mechanical injury in related areas.
Key Safety Points for Large Injection Molding Machines
Given the size and operational characteristics of large injection molding machines, intervention protection is an essential safety measure. Safety gates are the most commonly used form of intervention protection. The combination of RFID-based security coded non-contact switches (PSENcode) and highly resistant safety latches (PSENbolt ) can meet ISO 13849-1 PLr e and comply with EN 201 requirements.
PSENcode Safety Coded Non-Contact Switch
Compact design, lossless operation, long service life, IP67-rated housing for dust and water resistance, suitable for harsh industrial environments. Encoded RFID technology effectively prevents intentional human error.
Safety latch PSENbolt
Ergonomically designed, the safety doors are easier for on-site personnel to operate and offer a tag-locking mechanism, providing reliable mechanical protection during equipment maintenance.
The PSS 4000 is a better match for large injection molding machines!
When it comes to safety protection, besides sensors, controllers are of paramount importance. For large injection molding machines, the potential hazards that could cause injury to personnel are relatively dispersed and numerous. Therefore, in terms of safety control, the PSS 4000 system with distributed safety control functionality is highly recommended. It can control remote safety I/O sites through a distributed connection via a secure real-time Ethernet SafetyNET p .
Choosing an industry leader
Pilz boasts extensive practical experience and a comprehensive product line in the injection molding industry. Having participated in the formulation of national industry standards, Pilz possesses a deep understanding of these requirements and can provide cost-effective and safe solutions tailored to the specific needs of users, catering to different injection molding machine specifications. Thanks to years of industry expertise and the excellent reputation built by its professional team, Pilz has won the favor of numerous industry users, especially leading companies.
