Plastic Injection Molding Services
From rapid prototype tooling to high-volume production molds, RpProto — a China-based custom injection molding manufacturer — delivers precision plastic parts with tight tolerances, fast lead times, and competitive pricing. Supporting ABS, PC, PEEK, Nylon, TPU and 50+ thermoplastic materials.
RpProto, based in Xiamen, China, is a full-service plastic injection molding company providing end-to-end solutions from mold design to part production. I support both prototype tooling for design validation and production molds for mass manufacturing, with the capability to meet demanding technical and commercial requirements.
With over 20 years of experience in in-house mold making and injection molding machines ranging from 50 to 1,500 tons, We produce everything from small precision components to large automotive structural housings with consistent quality and tight tolerances. We maintain full control over mold quality, cost, and production timelines to ensure reliable results at every stage. All molds are built to SPI and VDI standards, with full DFM analysis provided before tooling begins to minimize risk and reduce iteration costs.
- In-house mold design and engineering
- Secondary operations and assembly
- Rapid tooling in as fast as 15 days
- Production tooling for high-volume runs
As a leading injection mold tooling factory. RpProto’s mold manufacturing engineer team manufacture hundreds of steel injection molds every year.
Soft steel molds for design validation and low-volume production. Perfect for testing fit, form, and function before committing to production tooling. Ideal for design validation, first article inspection, and small batch injection molding runs before committing to hardened production tooling.
- P20 steel
- Single cavity
- Manual or semi-auto
- Quick modifications
Semi-hardened steel molds that bridge the gap between prototyping and full production. Ideal for pilot runs and market testing.Suitable for pilot production, market testing, and bridging the gap while production molds are being manufactured — often used in automotive and medical device development cycles.
- P20 or 718H steel
- Multi-cavity options
- Production-grade finish
- Moderate modifications
Hardened steel molds built for high-volume, long-term production with maximum durability and precision. Built for long-term, high-volume injection molding production with repeatable dimensional accuracy and consistent cycle times.
- H13 or S136 steel
- Multi-cavity
- Hot runner systems
- Automated ejection
Not sure which tooling option fits your budget?
Read our injection molding cost guide for a full breakdown of tooling costs by mold type, volume, and material.
Materials of Injection Molding
We process 50+ thermoplastic and elastomeric materials for injection molding, including engineering-grade resins such as glass-filled nylon, flame-retardant ABS, and medical-grade polycarbonate. Material selection support is available for every project.
Engineering Plastics
Not sure which resin is right for your project? Our injection molding material guide covers 15+ resins with property data, processing conditions, and application examples.
Surface Finishes
Our injection molded parts can be finished to SPI A1 mirror polish, VDI textured matte, or custom painted and pad-printed finishes. Secondary operations include laser etching, ultrasonic welding, and heat staking for complete assembly-ready delivery.
We offer painting, pad printing, laser etching, ultrasonic welding, heat staking, and assembly services to deliver finished products ready for use.
Why Source Injection Molding from RpProto China
Sourcing custom injection molding from China can reduce tooling costs by 40–60% compared to US and European suppliers, without compromising quality. RpProto’s Xiamen factory combines competitive pricing with in-house mold design, rigorous quality control, and direct English communication — eliminating the risks commonly associated with offshore plastic injection molding.
Industries We Serve
Delivering injection molded components across diverse industries with specific quality and compliance requirements.
Medical Devices
Diagnostic equipment, surgical tools, drug delivery systems
Automotive Parts
Interior trim, under-hood components, lighting housings
Consumer Electronics
Housings, buttons, connectors, internal components
Industrial Equipment
Control panels, enclosures, machine components
Ready to Start Your Injection Molding Project?
Upload your CAD files and get a detailed quote including DFM feedback, tooling costs, and part pricing within 24 hours.
STL | STEP | SLDPRT | IGS | IPT | PRT | SAT files
- All of your files are safe and confidential.
Before we build your mold, our engineers review every part against our injection molding design guidelines.
Injection Molding Process
- Thermoplastic resin pellets are dried and fed into the injection molding machine.
- Inside the heated barrel, the plastic material is melted through controlled temperature and screw rotation.
- The molten plastic is injected into the mold cavity under high pressure. Once the cavity is filled, the plastic cools and solidifies inside the mold.
- After cooling, the mold opens and ejector pins release the finished plastic part.
- Post-processing includes trimming, painting, or assembly. All parts are inspected to ensure they meet RpProto’s quality standards and customer specifications.
FAQs
The largest mold we can manufacture is 2000 x 1600 x 1000 mm, and we can achieve precision tolerances as tight as ±0.02 mm.
Yes, we can do both! We manufacture double-color injection molds, and we can also run multiple colors of the same material on the same order. Please note that a purge charge will be added when running multiple colors on a single order.
Typically, it takes 3-5 weeks, depending on the mold size and complexity. For urgent projects, we can expedite the process.
We use a variety of high-quality steels based on the specific needs of each project, including P20, H13, 718, and S136. The choice depends on factors like mold durability, part volume, and the required finish.
Our molds can last between 300,000 and 1,000,000 shots, depending on the material used and maintenance practices.
After receiving the order, the statement of work is reviewed by one of our manufacturing engineers. A case manager is assigned, and an appropriate manufacturing supplier is identified. A comprehensive DFM/PEG report is created and provided for approval. Upon approval, tooling and mold production is commenced. T1 samples are produced and shipped for approval. Upon approval, the remaining parts are made.
Mold cost varies by complexity, cavity count, and steel grade. Simple single-cavity prototype molds start from $800–$2,000, while production molds range from $3,000 to $20,000+.
At RpProto, our customers own their injection mold tools! After a run is complete, the tool will remain at our facilities. Tools can be shipped to you upon request; however, you will be responsible for any associated shipping and packaging costs. Our engineers will work with you regarding tool compatibility with your equipment if you’re unsure.
There is no strict minimum. We support low-volume runs starting from 200–1000 pieces using rapid or bridge tooling, making us suitable for startups, product validation, and bridge production.
Yes. We supply injection molded components for medical devices, automotive interior trim, and consumer electronics with ISO 9001:2015 quality management and full inspection documentation.