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Extruding and Forming PVC Parts to Meet Your Design Build

Manufacturing Services & Engineering


When your application requires precise bends, cuts and angles, forming your market-specific part is a possible alternative to molding. Drain traps, formed rubber hoses, and formed PVC are just a few of the custom design solutions we offer. Our 4-step process of extruding and forming your part ensures we can work your components neatly inside your box in a way that’s designed and engineered to optimize space and function. 

What is a Formed Part? 

Formed pieces, such as drain traps, formed rubber hoses and formed PVC pipes, require an extra step in the manufacturing process. 

Simple shapes can be manufactured through extrusion; complex shapes that require precision angles or bends demand an additional step of forming that comes after the extrusion process. 

Why would your part require precise angles and bends? In most cases, the demand comes in order to fit a pipe or hose neatly and compactly in and around other components within your product without obstructing function or accessibility. 


An Example of a Formed PVC Pipe with Multiple Requirements

The above photo depicts a light commercial formed PVC drain with design specifications that necessitated the use of forming over extruding or molding. 

Part details include: 

  • Right End Threaded, Left End Flared
  • 90 Degree Bend and 45 Degree Turn
  • Machined Hole in Tubing Near Right End 

Extrusion vs Forming a Part 

Extrusion is the process of heating a material before forcing it through a shape. Extrusion is a more cost-effective option than molding since the die is more affordable. 

A part can be extruded as either a coil or cut to length. The complete process of manufacturing a finished part involves 3 steps:

  1. Extrusion
  2. Cutting
  3. Vulcanizing Edges

With the demand to create the shape around precise angles or bends comes the fourth step: 

      4. Forming the Part (Bending and Making it Into a Shape)

Factors to Consider in Manufacturing Molded vs Formed Parts  

When engineering your part, there are some important considerations to account for that will help determine which manufacturing process to choose: 

  • Volume and Budget: For larger volume production, molding might be a better alternative to forming. Typically, your budget will determine which of the two you’ll choose since forming is the more affordable option. 
  • Shapes: Die cutting is an option for both molding and forming; however, 
  • Application: Product function will in many cases determine material needs. Common market applications include:
    • Drain tubes for HVAC systems
    • ID-OD chords
    • Flexible tubing
  • Tolerancing: The process must be matched to the tolerance, and molding holds a tighter tolerance than forming. 

An example application ideal for the molding process would be a rubber tube that is lathe cut with the need for a tight tolerance. 

If you’re unsure which process would be ideal for your application or part, our expert engineering team will be happy to assist you in find the optimal solution. 

What Materials Can Be Used for Formed Parts? 

Many types of materials can be extruded and formed, but the most common include:

  • Plastics (PVC)
  • Silicone
  • Neoprene 
  • Foam
  • Rubber 

LEARN MORE: About PVC Pipes and PVC Piping Systems 

What’s the Difference Between Forming and Molding? 

Molding is the process of creating a part by compressing, injecting or transferring a material into a die-cut mold to create a specific shape. 

Forming occurs when a material is heated, then extruded, often into a coil or cut to length tubing. After curing, the product is again heated before being formed into its specific angle and shape. 


A Formed Drain Tube (L) vs a Molded Drain Tube (R)


A Cut-to-Length Molded Rubber Drain Tube

Why Choose Us? 

We are chemical experts in materials, with a large international sourcing arm and longstanding relationships with our global suppliers. 

We have over 40 years of experience in die cutting and parts manufacturing. We stay abreast of new industry standards and processes to ensure we maintain compliance and longevity through our international network of partners. 

Sur-Seal offers decades of experience in global sourcing, design engineering, and chemistry. Our reach and expertise is unmatched. 

Engineering, Design and Consulting Services

Project Design Process

Our goal is to design and follow the most efficient project roadmap to get you to the Minimum Viable Product (MVP). 

The earlier in the design process we are involved, the better we can save you time and money. Our engineers and chemists can optimize your build before it gets to the parts manufacturing stage. 

“We can help spec in materials that are unique – or in some cases, selecting an alternative – that yields a better margin for an overall lower cost.”

Gregg Szylakowski, Director of Engineering Solutions and Management at Sur-Seal


LEARN MORE: A Step-by-Step Guide to Building a Minimum Viable Product (MVP)

Design & Application Engineering 

Sur-Seal’s engineering team leverages their material expertise, supports the design process, and suggests design improvements toward efficiency and cost savings.

  • Jigs, Fixtures and Assembly Aids
  • Cost-Down Alternatives
  • Prototyping: Rapid, Full-Scale

Process Engineering

Our process engineers can execute Kaizen events on customer manufacturing lines. We also continuously engage in identifying and implementing efficiencies on our own manufacturing lines.

  • Custom Die Design, Fabrication and Repair
  • Reverse Engineering
  • Part Nesting Software

VA/VE – Value Analysis & Value Engineering 

Utilizing VA/VE principles allows our engineers to consistently evaluate designs in development, with an eye toward reduced costs and improved performance.

  • Review Incumbent Parts for Efficiency and Improvement
  • Early Stage Gate Design and Optimization 

LEARN MORE: Talk to a Specialist About Engineering Services 

Forming Parts: A Step Beyond Extrusion and a Cost-Effective Alternative to Molding

Like many solutions in concept design and manufacturing, your ideal solution is specific to your application. Weigh the pros and cons of extrusion, molding and formed parts and consider if you might benefit from choosing to form your part versus molding or extruding it. 

If you need some help with engineering and problem solving, our experienced team is always here to help. Contact our team to request a quote or begin your consultation

  • Why Sur-Seal
  • Brands We Sell Directly To

    Sikorsky Sikorsky

    Our Key Materials Partners