Chemicals & Plastics

Founded in 1978, Zhongde is a professional cnc machining company focusing on OEM & ODM customized services. Based on 40 years technology deposition, we have developed a one-stop solution from mold designing and rapid prototyping to mass production. Our manufacturing capabilities include plastic injection molding service, compression molding service, CNC machining service, metal stamping service, 3D printing service, custom molding service, overmoulding services, etc. Zhongde can provide over-molding and insert overmolding to produce unique multi-material parts. Our production materials range from thermoplastic to elastomer-rubber, as well as metal. We've broken down the differences and similarities between the two processes. Let us help you decide which process is right for your project. Both over-molding and insert molding processes involve putting two types of materials together to make one part,also named molding over molding. Overmolding is a two steps process that one to create the substrate and one for the oversold that goes on top of it. Insert molding is a slightly faster process as it takes only one step that the two materials are molded at the same time. Guideline of Overmolding & Insert Molding Insert molding injection is a process where a single part is created using two or more different materials in combination. Traditonally, overmolding starts with injection molding a hard plastic resin that has a higher melting point. Once that part is cooled, another material is injection molded over the first part, resulting in a single, finished product.We also offer injection molding threaded inserts. Insert molding combines metal and plastics into one single part. It allows plastic to bond to insert pieces, mostly brass or stainless steel metal component, which go inside a mold cavity. There are many options for insert that can be placed into the mold. A few of examples are warming labels, threaded bushings, wires, batteries, etc. Size of Overmolding & Insert Molding Below table shows the size of Overmolding & Insert Molding parts we usually make. If you need a larger size, we can also help you achieve it. Size Metric Inch Length 2500 98.4 Width 2000 78.7 Height 1500 59 Available Material of Overmolding And In sert Molding In addition to the general materials listed below, Zhongde can also modify the materials according to the special needs of customers. Our professional engineers will adjust the raw material formula to meet the unique conditions of use. Overmolding & Insert Molding Plastic ABS Acrylonitrile Butadiene Styrene PA 6 Polyamide 6, Nylon 6 PA 6/6 Polyamide 6/6, Nylon 6/6 POM Acetal Polyoxymethylene, Delrin PP Polypropylene PE Polyethylene LDPE Low-Density Polyethylene HDPE High-Density Polyethylene UHMWPE Ultrahigh Molecular Weight Polyethylene PTFE Polytetrafluoroethylene PEEK Polyether Ether Ketone PC Polycarbonate PMMA Polymethyl Methacrylate, Acrylic PS Polystyrene PVC Polyvinyl Chloride (Shore D) PU Polyurethane Overmolding & Insert molding Rubber NR Natural Rubber NBR Nitrile Rubber SBR Styrene-butadiene Rubber HNBR Hydrogenated Nitrile CR Neoprene Rubber VMQ Silicone LSR Liquid Silicone Rubber FVMQ Fluorosilicone FKM Fluorocarbon FFKM Perfluorocarbon Rubber EPDM Ethylene-Propylene Diene Monomer Rubber IR Polyisoprene Rubber IIR Butyl Rubber Additives of Overmolding & Insert Molding Name Description UV absorbers Absorb UV radiation, slowing down the degradation of the material when used outdoors. Flame retardants Prevent ignition and inhibits spread of fire. Plasticizers Increase flexibility and promotes plasticity, reducing brittleness of the material. Colorants Used to color plastics. Carbon fibers Increase strength, toughness, and rigidity of the material at the expense of making the material more brittle. Glass fibers Increase strength, toughness, and rigidity of the material at the expense of making the material more brittle. It is more flexible than carbon fibers. Surface Finishing of Overmolding & Insert Molding Name Description Glossy The mold is smoothed and then polished with a diamond buff, resulting in parts with a mirror-like finish. Semi-gloss The mold is smoothed with fine grit sandpaper, resulting in parts with a fine surface finish. Matte The mold is smoothed using fine stone powder, removing all machining marks. Textured finish The mold is first smoothed with fine stone powder and then sandblasted, resulting in a textured surface. As-machined finish The mold is finished to the machinist's discretion. Tool marks may be visible.