Precision Ejector Pin and Ejector Sleeve with 0.005mm Tolerance and Good Toughness for Plastic Injection Molds

Founded in 2012, Dongguan Senlan Mold Parts Co., Ltd. focuses on precision machining for mold components, with strong experience in custom non-standard parts for precision packaging molds.

Over the years, Senlan has supported customers across a wide range of industries with precision mold parts for multi-cavity molds and other demanding tooling applications. Our work goes beyond machining parts to size. We pay close attention to fit, consistency, and the details that affect mold performance in real production.

At Senlan Precision Parts, we believe good manufacturing should be dependable, practical, and clear. That is why we work closely from the drawing stage, control key processes carefully, and keep our focus on parts that are ready for assembly and stable in use.

Our core business is the custom machining of precision mold components.

We manufacture plastic cavities, core pins, inserts, moving core assemblies, cap sealing mold parts, and other non-standard mold components based on customer drawings. These parts are widely used in:

• cap and closure molds
• daily packaging molds
• cosmetic packaging molds
• medical consumable molds
• other precision packaging molds

In these applications, even a small variation can affect mold fitting, product consistency, or tool life. For that reason, we place strong focus on dimensional control, machining stability, and repeatability throughout production.

Precision work depends on using the right process for the right part.

Our main machining capabilities include 3-axis CNC machining, EDM, turning, grinding, polishing, and heat treatment. Different parts require different process combinations depending on their geometry, tolerance requirements, and surface finish needs.

For more complex parts, we plan the machining route step by step to achieve a better result. Some parts require EDM for narrow or difficult areas. Some require grinding for closer tolerances. Others need polishing or heat treatment to meet working requirements in the mold.

This flexible approach allows us to machine a wide range of precision mold components with better control over accuracy, finish, and consistency.

Quality control is built into our process from start to finish.

To verify part quality, we use inspection equipment such as Zeiss CMM, optical projector, hardness testers, and cylindricity measuring instruments. These tools help us check critical dimensions, fine features, hardness results, and roundness-related requirements with greater clarity.

Key dimensions are inspected during production and checked again before shipment. This helps us reduce variation, catch issues earlier, and improve fitting performance during mold assembly.

For us, quality inspection is not only about whether a part passes measurement. It is about whether the part performs as expected in real use.

Good parts also need clear communication and reliable follow-up.

At Senlan, our business support team works closely with customers from quotation to delivery. We help review drawings, confirm requirements, follow production progress, and keep project information updated throughout the process.

For custom mold parts, details matter. Material, tolerance, surface finish, heat treatment, inspection points, and delivery time all need to be confirmed clearly. Our team stays involved to help reduce misunderstandings, improve response speed, and keep projects moving in a more organized way.

We believe good service is not only about replying quickly. It is also about following the project carefully and making sure important information is clear at each step.

Our goal is simple: to make mold parts that meet the drawing, fit well, and perform reliably in production.

We understand that customers are not only buying a machined component. They are looking for parts that help reduce fitting issues, support smoother assembly, and contribute to more stable mold performance over time.