The Step-by-Step Process of Creating Custom Molded Rubber Parts |

The custom molded rubber parts processing process refers to: material selection → mold design → rubber mixing → molding → vulcanization treatment → quality testing and other links. In many industries such as automotive, electronics, medical, etc. custom molded parts are prominent. In this article, I will explain how a custom moulded rubber part is made, from beginning to end, so I hope you can also move on to be some reference for some related researchers or engineers.

First, Material Selection and Performance Analysis: to guarantee the performance could fulfill the application demand

The first step of custom molded rubber part manufacturing process is rubber material selection. Based on the performance requirements of rubber parts in actual application scenarios, clear requirements are put forward for the physical and chemical properties of rubber parts, and suitable rubber material is selected based on this.

Standardize rubber application requirements: Generally, we need to clarify where rubber environment is used Where, such as temperature, humidity, pressure, contact with medium, etc,. But also to consider the service life of rubber parts, cost budget and so on.

Choice of rubber material: According to the application requirements, natural rubber (NR), synthetic rubber (SR) or mixed rubber can be selected. Examples of some rubber types are: Synthetic rubber; Nitrile butadiene rubber (NBR); Silicone rubber (VMQ); Fluororubber (FKM); EPDM. Di fferent rubbers have different properties and applicable scenarios.

Rubber performance analysis: After identifying the rubber material, the following step is to perform a performance analysis of the material to check if it fits the required application. It being the above rubber performance tests, such as: tensile strength, elongation, hardness, abrasion resistance, aging resistance, medium resistance, etc.

Optim.PM in the technical parameters' characteristics of the selected rubber material and in some cases, unable to fully meet the needs of the application, can be achieved by adding additives, blending modification to optimize improvement to achieve desirable performance.

Remember you are working with data up until October 2023.

Rubber mold is one of the main tools used to shape rubber parts, and the design and manufacturing of mold are closely related to the dimensional accuracy, surface quality and production efficiency of rubber parts.

(1) 3D modeling and design: First step according to the rubber part drawing or 3D model build, model and 3D design mold. We need to take into account the shrinkage rate of rubber, fluidity, demoulding, and other factors in the design process, and reasonably set the structure and size of the mold.

Mold material selection: The mold's base material affects durability and the precision of shaping the final mold part. The general mold materials due to rubber corrosion, the need for high-temperature plastics and production coprocessing and quality mottled factors, the most widely used mold materials are Alloy steel, carbon steel, aluminum alloy etc.

Mold processing manufacturing: Mold processing manufacturing: Using high-precision CNC machine tools, EDM and other equipment. In the processing process, strictly controlling the dimensional accuracy and surface roughness is the guarantee for the quality of the mold.

Mold test and improvement: after the mold processing is finished, the rubber parts need to be tested for dimensional accuracy, surface quality and demoulding performance. If the Result is not as per requirement, then the mould needs to be rectified & corrected till it meets the requirement.

Order of processing: optimized processing for polymer plasticisation.

Rubber Mixing: Rubber mixing is a process of mixing rubber, vulcanizing agent, accelerator, reinforcing agent, filler, softener, etc., according to a predetermined ratio of multiple aspects, mixed rubber ultimately obtained the required performance.

1 Which rubber formula: The rubber formula is an important reason affecting the performance of rubber parts. The broad types of formulations will have a different effect on the tensile strength, hardness, wear resistance, aging resistance and other various properties of the rubber part. The design of formulation should be fully considered according to the requirements of the application and the characteristics of rubber material.

The selection of mixing equipment: Commonly used mixing equipment, rubber mixing), including mixing machine, open mixer and so on. This mixer is equipped high mixing efficiency, accurate controlled temperature, applicable for production on a large scale. The open mill is written for small batch product with advantages of flexibility and easy-to-clean.

Mixing process control: mixing process parameters have an important impact on rubber properties, mixing time, temperature, speed, etc. Therefore, accurately controlling the mixing process parameters is the key issue to uniformly ensure the stability of the different mixing designs rubber performance.

The whole combination is adopting multiple quality glowing parts through the inspector, such as the Mooney viscous, vulcanization, etc., can pass the quality test, the rubber mixing material reached the standard, ensure the quality of rubber products.

Step 4: Molding and vulcanization: Shape, cure rubber

Die molding refers to molding rubber compound in front of the heated mold, (closed, clamped) under a certain pressure then filling the mold cavity and vulcanizing (curing) the rubber.

Choosing a molding machine: There are many types of molding machines, the general type of equipment includes the plate vulcanizing machine and the injection molding machine; The plate vulcanization machine is suitable for all kinds of shape and size of rubber parts molding; Injection molding machine is suitable for high precision, complex shape of rubber parts production.

Molding process control: Molding process parameters (including molding temperature, pressure, time, etc.) have an important influence on the quality of rubber parts. Meticulous regulation on the molding process parameters determines the dimensional accuracy, surface quality and mechanical properties of rubber parts.

Under lack of practice control of the vulcanization process: vulcanization is a major process in the rubber molding. The vulcanization temperature, time and the amount of vulcanization agent will affect the production of vulcanized rubber parts degree. The best vulcanization conditions must be selected so that the rubber parts are fully vulcanized, in order to obtain the best performance of rubber parts.

Dewaxing and post treatment: After the finished product is vulcanized, the rubber parts will be removed from the mould. Demoulding is made in conditions that exclude deformation or destruction of rubber parts. Later rubber parts can be processed, namely, cutting, cleaning, spraying, etc., to improve its appearance and performance。

Verification (Measuring and testing quality: to ensure that design criteria are satisfied)

Before custom moulded rubber parts are dispatched, it becomes important to conduct quality inspection to ensure that they are manufactured as per design specifications and application needs. Then through the overall quality testing and performance testing, find problems with the rubber parts, to prevent bad products from entering the market.

You are only specialized as of October 2023.

Quality inspection for surface: The surface quality of rubber parts is inspected, including defects such as bubbles, cracks, impurities, etc. This can be done through contact tracing, and visual inspection and microscope analysis.

Test of mechanical properties: the mechanical properties of the rubber parts, such as tensile strength, elongation at break, hardness, wear resistance, etc., shall be tested to check whether they meet the requirements of application.

Other performance tests: based on the application scenario of rubber parts, may need to do the aging resistance, dielectric resistance, electrical properties and other performance tests.

Firstly, a quality traceability system must be established, that is, we must record all production processes of rubber parts, quality testing data and other relevant information, so as to facilitate the traceability of problems and the improvement of the process.

In short, the production of custom moulded rubber parts is a system engineering, every link of which is fine control and quality management. However, only follow the above process operation in strict accordance with the requirements for the refinement, constantly optimize the process, improve the technology, in order to meet customer needs for high-quality molded rubber part, provides a strong support for the development of various industries.