(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.

Frame Work on an Injection Molding Rejuvenation Technique for Cable Insulation Failure

Rejuvenation technique on cable insulation failures is a hot topic in improving production benefits for electric related enterprises. Breaking the traditional thought of repair action without extensive former damage in scale of the cable insulation, the proposed technique starts from the local standard geometry elimination on insulation or sheaths around cable insulation failure section(s). And then, one standard injection molding technique is applied for rejuvenation on eliminated insulation no matter of the failure resulting from water tree or local mechanical damage or other modes. By this advancement, an injection molding technique is perfectly developed for rejuvenation on cable insulation failure. Frame work on this technigue is hear introduced and it consists of three branches including injection molding material development, standard injection plastic molding technique, and coded quality approval regularities. Realizability and reliability of the present technigue have been verified by sampling testing to expect to be wide applied in production.

Low-temperature sintering of high-siliceous clay under conditions of oxygen deficiency

In the work, the processes of phase reconstruction and properties of ceramics obtained from high-siliceous clay-sand, clay-cullet, and clay-sand-cullet mixtures are considered. It is possible to perform plastic molding of blanks from the given mixtures due to the presence of montmorillonite in clay and sand and sintering at 800 oC for 8 h under conditions of oxygen deficiency. Depending on the composition of the initial mixtures, specimens ranging in color from gray to black can be obtained. It has been established by the XRD, IR spectroscopy, and electron microscopy methods that the synthesized material is glass ceramics consisting of quartz, feldspars, and a glass phase. Depending on the content of the initial components in the mixtures, it is possible to obtain glass ceramics with high strength properties or coarse-pored glass ceramics whose properties are similar to those of foamed ceramics.

Application of the method of current functions in stationary plastic deformation processes

A method of determining the components of the strain rate tensor based on the method of current functions is developed. It is assumed that, with an axisymmetric plastic deformation of the metal in a channel with curvilinear borders, the kinematics of the process are similar to a flat flow. Using the incompressibility equation and the differential equation of the current lines, it is established that the current function maintains a constant value along the current lines. Two infinitely close current lines are considered in the flow plane to explain the kinematic content of the current function. The expression for flow through the finite transverse-sized tube was obtained. In the absence of radial velocity components at the boundaries, we obtain the restrictions imposed on derivatives of the current functions at these boundaries. The method of calculation of kinematic deformation characteristics for established axisymmetric processes will allow to simplify the mathematical processing of the obtained results. Real processes of metal processing are always accompanied by uneven plastic molding, which affects the power and kinematic parameters, the quality of finished products. The main technological factors affecting the appearance of the inhomogeneity and the nature of its distribution are the form factor (geometric parameters of the original workpiece) and the coefficient of contact friction. The study of technological parameters affecting the distribution of non-uniformity of plastic molding will allow to create practical recommendations for reducing the influence of the above mentioned parameters to ensure more uniform plastic deformation. Due to elastic-plastic deformation and local heating, which occur during surface-plastic deformation processing, the stress-strain and physical state of the surface layer is formed. This changes the microgeometry of the surface, the physical and mechanical properties of the surface layer of the workpiece. The surface treated by methods of surface-plastic deformation, has high hardness, residual compression stresses in the surface layer, smoothed out the micro-roughness. Accordingly, increases wear resistance, fatigue strength, resistance to corrosion and more.