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Advantages of Partnering With an RFQUSA-Recommended Injection Molding Company

There are hundreds of injection molding companies that offer custom plastic manufacturing services. Sorting through pages of Google results to find one with the right capabilities, certifications, and relevant industry experience can be time-consuming.

This is why the experts at RFQUSA have compiled the list below of top plastic injection molding manufacturers. Working with an established injection molder provides the following benefits:

• Optimized Mold Design & Tooling: Proper tooling addresses material flow and cooling patterns upfront to prevent warping, sink marks, and dimensional inconsistencies.
• RFQUSA Recommends: Seaway Plastics for expert mold design and tooling services.

• Lower defect rates and scrap costs: Proven molding processes, in-house tooling expertise, and advanced inspection reduce the chances of part failures, dimensional issues, and costly rework.
• RFQUSA Recommends: American Plastics for ISO 9001-certified injection molding.

• Repeatable quality across production runs: Established molders use scientific molding principles and process monitoring to maintain tight tolerances, whether producing 100 parts or 1 million.
• RFQUSA Recommends:  Polymer Molding for innovative polymer-injected molded parts.

• Access to specialized capabilities: Leading injection molders invest in micro molding equipment, cleanroom facilities, advanced metrology systems, and technical expertise that most companies cannot justify maintaining internally.
• RFQUSA Recommends: GD&T for geometric dimensioning & tolerancing quality control to ensure consistent quality for injection molded parts. *GD&T is not an injection molding company, but specializes in geometric dimensioning and tolerance control.

• Long-term cost savings: Quality tooling and optimized processes reduce per-part costs, minimize production delays, and extend mold life across the program timeline.
• RFQUSA Recommends: Progress for Industry (PFI) for injection mold plating services to improve the longevity of molds and maintain tolerances.

Frequently Asked Questions About Injection Molding Companies

Several factors will allow you to make a more informed decision when it comes to choosing from our list of the best plastic injection molding manufacturers.

Q: What certifications should an injection molding company have?

A: ISO 13485:2016 is required for medical device components. ISO 9001:2015 covers general manufacturing quality, IATF 16949 applies to automotive work, and food/beverage packaging requires AIB certification and cleanroom facilities.

Q: What’s the difference between a mold maker and an injection molder?

A: A mold maker designs and builds the precision steel molds, while an injection molder operates the presses to produce plastic parts. Companies offering both services in-house provide faster communication, shorter lead times, and better troubleshooting capabilities.

Q: How do I choose the right injection molding partner for my project?

A: Match the company’s capabilities to your specific requirements: part size/tolerances, production volume, industry experience, and required certifications. Verify they offer essential services like DFM engineering, in-house tooling, materials expertise, and any secondary operations (assembly, finishing, inspection) you need.

Q: What value-added services should I expect from an injection molding company?

A: Top plastic injection molding manufacturers will offer DFM engineering to optimize part designs, in-house tooling for faster iterations, and advanced inspection/metrology to ensure quality. They should also provide secondary operations (assembly, welding, printing, packaging) and prototyping services to consolidate your supply chain.

Comparing the Top Injection Molding Manufacturers

The table below highlights location and service offerings for each of the top 10 metal finishing companies:

#1. American Plastics

American Plastics is an ISO 9001-certified injection molder in Glendale, Arizona. The company operates 13 presses, ranging from 55 to 400 tons, with shot sizes up to 54 ounces. They handle UL-certified plastic parts and provide complete turnkey solutions, including mold design, tooling, hot stamping, pad printing, and final packaging.

Rigorous testing and inspection run through a documented three-tier quality control system. All assembly, packaging, and drop ship support happen on-site to keep completed parts in one facility.

#2. Seaway Plastics

Seaway Plastics is an ISO 13485 certified injection molding manufacturer with locations in Port Richey, Brooksville, Florida, Santa Rosa, CA (Wright Engineered Plastics), and St. Paul, MN (MME Group). In addition to plastic injection molding, they also offer in-house tooling, cleanroom molding and assembly, heat staking, sonic welding, CNC machining, painting, and packaging services.

Seaway has experience with over 700 different plastic resins and builds aluminum, steel, and combination molds ranging from Class 105 to Class 101. Their facilities feature Mantle’s Automated Toolmaking System for rapid tooling production.

#3. Polymer Molding, Inc.

Polymer Molding produces custom plastic injection molded parts at its Erie, Pennsylvania, location. Services extend to in-house tool-building, prototype development, mold maintenance, and secondary operations.

PMI holds ISO 9001:2015 certification and focuses on protective coverings, closures, and components for contamination prevention and shipping protection. Their product line includes caps, plugs, tube inserts, and more.

#4. Viking Plastics

Viking Plastics provides custom plastic injection molding for automotive, HVAC, and industrial markets. The company offers 2-shot molding, insert molding, tight tolerance molding, automated and manual assembly, ultrasonic and vibration welding, hot stamping, and pad printing.

With over 50 years of experience, Viking Plastics carries IATF 16949:2016, ISO 14001:2015, and ISO 9001:2015 certifications. They manufacture a wide range of products, including sealing system components, valve caps, and A/C line applications.

#5. Beaumont Advanced Processing (BAP)

Beaumont Advanced Processing delivers plastic injection molding solutions in Erie, Pennsylvania. BAP’s service portfolio includes material characterization, test specimen molding, tooling services, mold sampling, and consulting.

BAP maintains ISO 9001:2015 and ISO 13485:2016 certifications with Class 8 cleanroom injection molding capabilities per ISO 14644-1:2015 standards. Their material characterization services include Moldflow analysis and proprietary Therma-flo™ testing.

#6. Hi-Rel Plastics

Hi-Rel Plastics handles custom plastic injection molding and blow molding in Riverside, California. Beyond core molding, they provide product design, 3D printing, mold making, CNC machining, ultrasonic welding, and custom packaging.

Operating for over 40 years, Hi-Rel maintains ISO 9001:2015, AS 9100 Rev D, and ISO 13485:2016 certifications. Their ISO 7 Class 10,000 cleanroom manufacturing space supports micro molding and overmolding applications.

#7. New Berlin Plastics

New Berlin Plastics is a custom plastic injection molder in New Berlin, Wisconsin. Their LaunchLogic process supports resin selection, design for manufacturability, mold flow analysis, tool design, program management, and transfer tooling.

They achieve a 99.8% customer acceptance rate and 2.2% internal scrap rate using scientific injection molding practices. New Berlin Plastics holds ISO 9001:2015 and ISO 13485:2016 certifications and works with automotive, healthcare, and industrial equipment manufacturers.

#8. D&M Plastics

D&M Plastics manufactures high-precision injection-molded parts in Burlington, Illinois. They offer specialized manufacturing capabilities, including overmolding, insert molding, and cleanroom injection molding, alongside several value-added services.

D&M brings nearly 50 years of experience to medical, automotive, electronics, and defense applications. The company is ISO 9001:2015 and ISO 13485:2016 certified with a focus on tight-tolerance precision parts and lean manufacturing practices.

#9. AdvanTech Plastics

AdvanTech Plastics focuses on high-volume plastic injection molding in Woodstock, Illinois. Services include micro molding, insert molding, two-shot molding, pad printing, sonic welding, assembly, and in-mold labeling.

Established over 30 years ago, AdvanTech operates ISO Class 7 and Class 8 cleanroom facilities certified to ISO 13485:2016, ISO 9001:2015, and AIB standards. They use 96-cavity tooling, robotics, and scientific molding for medical devices, food, and beverage packaging.

#10. Matrix Plastic

Matrix Plastic Products focuses on precision injection molding and mold making for medical device manufacturers in Wood Dale, Illinois. Services include in-house DFM engineering, tooling, micro molding, assembly, and advanced inspection protocols.

This 50-year-old company produces ultra-precise components for minimally invasive surgery and micro medical devices. They’re ISO 13485:2016 and ISO 9001:2015 certified and handle close-tolerance molding programs for medical, electronics, and safety industries.

Get a Quote From a Trusted Injection Molder

Working with skilled injection molding manufacturers improves part quality and streamlines production timelines. Proven molding processes, in-house tooling capabilities, and DFM expertise help reduce defect rates and optimize designs for manufacturability.

Click below to get a quote and explore a curated list of the best plastic injection molding manufacturers.

Discover the Top Plastic Injection Molding Manufacturers