Injection moulding parts manufacturer and supplier in China: Compression Molding vs. Injection Molding – Compression molding and injection molding are both key plastic-forming methods, but they differ in material behavior, cost, and part design flexibility. Compression molding typically uses thermosetting materials and reinforced composites, while injection molding primarily handles thermoplastics. The former is ideal for producing large, high-strength components, whereas the latter excels in small, precise, high-volume parts. Compression molding generally involves lower tooling costs and simpler mold designs but requires longer cycle times. In contrast, injection molding offers faster production rates but higher setup expenses. Compression molding also accommodates higher fiber content, providing superior mechanical properties and heat resistance. Consequently, manufacturers choose between the two based on performance needs and production scale. Many industries, including automotive and aerospace, use both processes strategically—compression molding for structural parts and injection molding for intricate or lightweight components. Find many more info on Mulan Manufacturing Group.
Only high-quality molds can produce high-quality products. Many times we will receive feedback from customers, “I don’t agree with the price of your injection mold, why is it so high?”. Such problems are mainly concentrated in non-professional mold technicians, who only calculate the average cost of the mold on the product, without real research and exploration, how important a high-quality mold is to the quality of the product and the progress of the overall project. We have many methods for low-cost molds, but we have lost 100% of the assurance of the quality of your products. The cost of the mold depends on the size, structure, material, product quantity and other special requirements of the part. For example: if you need 1,000 injection parts, then we will actively recommend that you choose a low-cost single-cavity mold, which can meet the quality and deliver the product on time. The most important thing is low-cost investment.
Materials Used in Blow Molding – The success of blow molding depends largely on the choice of plastic. Common materials include high-density polyethylene (HDPE) , polyethylene terephthalate (PET) , polypropylene (PP) , and polyvinyl chloride (PVC) . HDPE is widely used for its toughness and chemical resistance, making it ideal for detergent and milk bottles. PET is preferred for clear, lightweight beverage bottles due to its strength and recyclability. PP offers superior heat resistance, used in containers that must endure higher temperatures. PVC, once popular, has seen reduced use due to environmental concerns. Modern trends emphasize sustainability, pushing manufacturers toward bio-based plastics and recyclable polymers. Material selection not only influences mechanical properties but also affects processing conditions like temperature, cooling time, and blow pressure. As material science advances, new resins continue to expand the possibilities for blow-molded designs, enabling stronger, lighter, and more sustainable products.
Blow molding is widely used in the production of hollow structure products, such as: water bottles, oil drums, chemical turnover barrels, floats, medical reagent bottles, etc. Injection blow molding is suitable for small container production, and stretch blow molding is suitable for medium and large-volume container products. However, the surface effect of injection blow molded products is better than stretch blow molding, and can be highly transparent and flat. Drinking water bottles are the most typical injection blow molding. Blow molding has many limitations due to the molding principle, so there are a few points that should be paid attention to when designing blow molding products: Only limited to hollow structural parts. The wall thickness is thin and the strength is low. By adding other materials in the multilayer part, the effect of blocking sound and heat sources is increased. (So not recyclable) A second trimming is required to remove burrs and excess material.
Mulan Group’s sheet metal prototype manufacturing services can meet the needs of small batch sheet metal manufacturing and plastic molding processes. Through one-stop manufacturing solutions, we provide buyers with the most cost-effective and fast-turnover on-demand manufacturing services. After years of accumulated manufacturing experience, we can provide a wide selection of sheet metal materials, which can fully meet the specifications and application functions of your sheet metal prototype.
Place the thermoset plastic material in the compression molds cavity, melt the thermoset material by heating, close the mold with pressure, and the melted thermoset material will instantly fill the entire cavity under the action of pressure. In this process, it is very important to control the weight, shape, and specifications of solid materials, which will directly affect product quality. Thermosetting materials will reach the best curing state under the control of stable high pressure and high temperature. Compression molding parts are ejected, and the remaining materials are cleaned manually or by using cutting molds.
Ally Bronstein
Tommy Pattison