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Taizhou Union Plastic Mould Co.,Ltd

ADD:No.26, MaoFeng Street, Beicheng Development Area, Huangyan Dist., Taizhou, Zhejiang, China

Post Code: 312080

Contact:Ms vicky






What's In The Injection Mold, Do You Know?
Aug 16, 2018

Structure though because of the plastic varieties and properties of the mold plastic products shape and structure and may be different with the type of injection machine and so on, but the basic structure is the same Mold is mainly composed of gating system thermal control system molding parts and structural parts The gating system and is part of the direct contact with plastic molding parts, and with the plastic and products, is the most complicated in the mold, the biggest change, request processing smoothness and accuracy of the highest part of the injection mould consists of two parts, dynamic model and fixed model, dynamic model installed on the movement of the injection molding machine templates, fixed die is installed on the injection moulding machine fixed templateDynamic model in injection molding and mold closing a gating system and the cavity, cavity when moving die and die separation in order to take out the plastic products In order to reduce the mold design and manufacturing of heavy workload, the injection mold is mostly adopted a system of standard mould base casting gating system refers to the plastic from the nozzle into the mold cavity in front of the flow channel section, including the mainstream way cold hole distributary channel and the gate, etc Pouring system is also called the runner system, it is the plastic melt by the injection machine nozzle to the cavity of a group of feeding channel, usually by the mainstream way distributary channel of gate and cold material point It is directly related to the plastic molding quality and production efficiency of the mainstream wayIt is mold injection molding machine nozzle to bypass or cavity of a passage way at the top of the mainstream is concave to the mainstream way import linking to the nozzle diameter should be slightly bigger than the nozzle diameter (0.8 mm) in order to avoid overflow of material, and to prevent both occur due to cohesion are not allowed to block imports diameter according to the size of the products and decide, mainstream way is commonly 4 to 8 mm diameter to expand inside tends to be the point of view of three to five, so that the flow of encumbrances demoulding slag hole it is located in the end of the mainstream way a hole, used to capture nozzle end between two injections of cold material, thus preventing shunt or gate jamsIf once the cold material mixed with cavity, easy to produce internal stress in the products made by cold material point of about 8 to 10 mm in diameter, depth of 6 mm stripping, to facilitate its often borne by the ejection rod parting at the bottom of the bar at the top of the hook should be designed to be twists and turns or set sinking groove, so that can smooth out the mainstream way when demoulding encumbrances Shunt way It is more slot connection in the mainstream way and channel of each cavity To make the molten material fill the cavity with constant velocity and the arrangement of distributary channel on the mold should be symmetrical and equidistance into distribution Distributary channel cross section shape and size of the plastic melt flow products demoulding and mold manufacturing difficulty are affectedIf flow, according to the equal capacity is the least resistance of the duct flow in a circular cross section But on smaller than the surface of the cylindrical passage, adverse to the cooling of the shunt way encumbrances, and that the shunt way must be opened in two and a half, both work and not easy alignment Often use, therefore, trapezoid or semicircular cross section of distributary channel, and to open in half with a knockout pin mold flow on the surface must be polished in order to reduce flow resistance to provide faster runner mold filling speed depends on the size of the plastic varieties, the size and thickness of the productsFor most thermoplastics, distributary channel cross section width is not more than 8 m, can be up to 10 to 12 m of very, very small in the premise of satisfying need 2-3 m should try to reduce the sectional area, to increase the shunt way encumbrances and prolong cooling gate it is connected to the mainstream way (or diversion) with cavity channel tunnel sectional area can equals the mainstream way (or diversion), but usually smaller so it is the minimum cross-sectional area in the runner system part of the gate of the shape and size of A great influence on the product quality the gate A controlling material flow rate:B can prevent backflow due to early coagulation of the molten material in this part during injection:D products from runner system Gate shape size and location of design depends on the nature of the plastic products and the size of the structure General cross section shape of the gate is rectangular or circular, sectional area should be small and the length should be short, it is not only based on the above work, but also because of small gate greaten easier, and big narrow gate is very difficult Gate location generally should choose the products the most thick and does not affect the appearance Gate design should take into account the size of the plastic melt it is the nature of the cavity die molding plastic products in the space for use as components in a cavity are collectively referred to as molding parts each molding parts often have special nameProducts appearance molding parts called die (also known as the cavity die), constitute products internal shape (such as hole groove, etc.) are called core or punch (also called male mold) design when molding parts according to the first of the performance of the plastic products geometry size tolerance and use requirements to determine the overall structure of the cavity followed by choose according to determine the structure of the parting surface of gate and vent locations and demoulding ways finally, according to the size of control products for the design of the parts and the combination between the parts of plastic melt into the cavity of high pressure, thus forming parts must carry on the reasonable selection and checking of strength and stiffnessIn order to ensure the plastic products surface bright and clean and beautiful and easy mold release, all contact with the plastic surface, the roughness Ra > 0.32 um, usually by heat treatment and corrosion resistant molding parts to improve the hardness, and selection of corrosion resistant steel manufacturing thermal control system In order to meet the requirements of injection process for mold temperature, there needs to be adjusted by the thermal control system of mold temperature For thermoplastic injection mold, mainly cooling system designed to make the mold cooling mold cooling of the commonly used method is to open cooling water channel in the mould, the use of circulating cooling water take mold heat;Mould heating besides can use hot water or steam cooling water channel, also can install inside the mold and the surrounding electric heating elements forming parts refers to the various parts of the product shape, including dynamic model fixed mold and molding cavity core rod and vent, etc Molding parts consists of core and die core form the products of the inner surface, the surface shape of die forming products will constitute the core and cavity after clamping mould cavity in accordance with the requirements of process and manufacturing sometimes by a number of core and concave die block, sometimes make it whole, only in hard machining easily damaged parts adopt insert ventIt is a trough in the mould opening the outlet, which indicates and molten material into the gas discharge When the molten material into the cavity, the original in the air in the cavity and the melt into the gas must be at the end of the material flow through the vent to mold discharging, otherwise will make bad products with porosity after molding, and accumulated due to compressed air to produce high temperature and even burn Under normal circumstances, the vent can be located within a cavity at the end of the molten material flows, can also be used in the mold parting surface Which is at the side of the die opening deep 0.03 0.2 mm, 1.5 6 mm wide shallow grooveInjection, vent will not have a lot of liquid leakage, because will be melting cooling solidification will channel closed vent opening position not to the operator, to prevent molten material spewed hurt accidentally In addition, also can use ejection rod and fit clearance of ejection hole, the top piece and the stripper plate and the fit clearance of core to exhaust structure parts It refers to various parts of the mold structure, including: oriented parting core-pulling and classification of the various parts Such as before and after the splint buckles template before and after bearing plate pressure column guide column stripper plate ejection rod and push pin 1. Guide partsIn order to ensure the moving die and die in correctly to when clamping, must be set on a mould parts Usually used in injection mold of four groups of guide pin and guide sleeve to guide parts, sometimes need to separately set up each other in the dynamic model and fixed die of male cone to assist in position 2. Launch mechanism in the process of open mold, need to have a launch institutions will plastic products and condensation of material in the flow passage of push or pull out the fixed plate and push plate to clamping putter General is fixed in the push rod have reset lever, reset lever in moving die or die to reset the push plate (3) when the side core-pulling mechanismSome plastic products with side concave or side hole must be divided in the side before being pushed out. After pulling out the side core, the side core can be removed smoothly