PLANNING AND SCHEDULE OF MAINTENANCE WORKS FOR INJECTION MACHINES

Keeping the equipment and machinery in working order is a very important activity in the field of industrial production, being specific to the maintenance department within an enterprise. Ensuring an optimal in operation of the manufacturing systems is closely related to the prevention of defects, an action that must be found in a planning and scheduling of preventive-planned maintenance works. In the paper, in addition to the introductory part on the main objectives and implementation of the maintenance system and maintenance-specific operations, a case study is conducted for the planning and organization of maintenance in a company equipped with plastic injection machines. The main stages developed consisted in elaborating the maintenance plan, establishing the optimal moment for replacing the machine tools, choosing the optimal type of machine tool and establishing the elements of random wear of the machine tools. It is concluded that the optimal type of injection molding machine that will be chosen to replace the T10 injection molding machine is T14, because it has a minimum average cost of acquisition, maintenance and repair, respectively 42.286 UV.

Education in plastics manufacturing: Aluminum mold making and injection molding

Plastics are ubiquitous in the modern world with both positive and negative consequences. Students will benefit from understanding how plastics are manufactured. They will be more aware of the material and have a better appreciation for the need to recycle. Injection molding is one of the primary plastics manufacturing methods and hobby scale injection molding machines can be used to educate students about plastics and polymers. Furthermore, it is possible to create custom injection molds from aluminum using similar hobby scale tools. In this article, experiences introducing injection molding in the classroom and experiences with mold making as a senior design project are presented. Suggestions and procedures for using the injection molding machine and for creating custom aluminum molds are covered.

Optimal design on Watt-chain double-toggle mold clamping mechanism for injection molding machine

Introduction The mode clamping mechanism is the most important part of forming section for the plastic injection molding machine. If this mechanism has double-toggle effects at the close position, it will get a larger clamping force and have higher safety. This study focuses on the optimal design of the Watt-chain mechanism with double-toggle effects at the close position. Methods The Watt-chain double-toggle mechanism is chosen to be the mold clamping mechanism by referring to the existing patents. Then, the kinematic characteristics of the Watt-chain double-toggle mechanism are analyzed by the vector loop method. Finally, based on the kinematic requirements and the proposed optimal design process according to the objective function, the optimal design on Watt-chain double-toggle mechanism is accomplished in this study. Results This study proposes an optimal design process on Watt-chain double-toggle mold clamping mechanism. By following the optimal design process, the optimal Watt-chain double-toggle mold clamping mechanism has a maximum acceleration 3418 mm/s2 ( amax = 3418 mm/s2) and a force ratio is 2.24 ( Fin/ Fout = 2.24). Discussion According to the studies on the optimal designs of mechanisms, the optimal Watt-chain double-toggle mechanism, which is better than the multiple-joint double-toggle mold clamping mechanism in the existing patent by reducing 19.5% of acceleration and 30% of a driving force, is proposed. The results of this study could be the design reference in engineering when designing mold clamping mechanisms for plastic injection molding machines.

Feedback Control of Injection Rate of the Injection Molding Machine Based on PID Improved by Unsaturated Integral

In conventional proportional–integral–derivative (PID) control, the integral term occupies a significant amount of controller memory, which prolongs the calculation time. The integral term easily leads to overshooting and oscillation, while the derivative term reduces the controller's anti-interference ability. In view of these problems, a PID expression with a recurrence relationship was derived, and the integral and differential terms of the conventional PID model were improved using an unsaturated integral and passivation differential to achieve a good control effect. Then, the improved PID was applied to the injection speed control of an injection molding machine, which is usually controlled using conventional PID control that featured difficulty in mathematical modeling, a nonlinear relationship between the input and the output, and high system complexity. Taking an injection molding machine as the control object, the transfer function of the injection system was constructed. Then, the improved PID was simulated using Matlab/Simulink. Lastly, the improved PID was verified using experiments. The simulation and the experimental results showed that the control model had a rapid response, no overshoot, and a high precision.

Overall Equipment Effectiveness to Increase Productivity of Injection Molding Machine: A Case Study in Plastic Manufacturing Industry

In line with the unstable market conditions in Indonesia, especially the plastic manufacturing industry, the companies need to be well prepared to survive. There were two research goals. First, it was to find out why the Overall Equipment Effectiveness (OEE) rate at the company did not meet the expected standard. Second, it was to determine what improvement should be made to increase the OEE for the machine. The research applied a case study in one of the plastic manufacturing industries located in Tangerang, Indonesia. It focused on the performance of Toshiba injection molding machine number 42/IS 450 GSW. The analysis was performed by applying Failure Mode and Effect Analysis (FMEA) with support from other tools such as Pareto chart, Cause and Effect Diagram (CED), and six big losses. By following the whole framework of the research, it finds causes of why the OEE does not meet the target. Then, from the results, it can be concluded that the implementation of the methods has a positive impact on the company. The OEE rate increases from an average of 26,43% to 78,87%. It means the OEE rate has achieved the company target of 75%.

(MOLDING DESIGN OF PADANG STATE POLYTECHNIC LOGO SOUVENIR MOLDING ON PRESSED PLASTIC INJECTION MOLDING MACHINE 1,960 KG / CM²)

ABSTRACT Padang State Polytechnic has been established since 1987 under the name Polytechnic Engineering and then changed its name several times to the management policy by Andalas University then, until now it is independent until now with the name Padang State Polytechnic. The 33-year-old polytechnic of the Padang State Polytechnic establishment must have an icon, symbol and trinkets that have PNP characteristics so that they are easy to recognize and remember. Souvenirs are a form of applying media for promotion and souvenirs for people who already know and come to Padang State Polytechnic. Plastic injection molding machine is a machine used to mold plastics with a basic material in the form of plastic pellets. Plastic injection molding machine is the process of processing plastic material in the form of seeds which are heated until they become liquid and then injected into the molding which then freezes / hardens according to the shape of the mold. The products produced by injection molding machines vary, from electronic tools, automotive tools, home appliances, plastic souvenirs, to tableware. The success of the resulting product is highly dependent on Molding. The plastic injection molding machine has parts, namely the Injection Unit, Molding Unit and Clamping Unit. The Injection Unit and Clamping Unit are the most important parts in the manufacturing process of plastic products where the control operation is executed on the control panel found on the plastic injection molding machine. The control panel on the machine can adjust the amount of clamping pressure, stroke length, plastic volume, and temperature used. The molding unit is the main part of the plastic product manufacturing process. Mold (mold) is a tool / tool used to make products according to the desired design (shape and dimensions). Plastic molding has its respective functions, parts of the mold, namely Cavity and Core, Sprue, Runner and Gate, Undercut. The printing process on a Plastic Molding machine has several stages such as the cutting process, mold safety and machine safety, execution, product check, setting, execution, and final. Materials used in the Plastic Molding process are usually materials that are often used daily and are safe for use by all groups, such as Polyproplene, Polycarbonate, and High Density Poly Ethylene. The product that will be produced from the molding made is a key toy souvenir made of plastic, with a shape like the Padang State Polytechnic logo, measuring 6 cm long, 6 cm wide and 5 mm thick. The test results obtained will be shown through field applications, socialization at the Padang State Polytechnic and writing in national journals are the targets and outputs of this novice lecturer research activity. Keywords— Mold, Souvenir, Cavity, Core, Pnp.