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Industrial Flanges | Expansion Joints | Pipe Fittings | Custom Machined Parts

Industry Leader
Engineering Solutions

We manufacture standard and custom steel flanges to meet the highest quality standards, including AWWA and ANSI specifications. Our flanges are developed for Agriculture, Waterworks, HVAC, Exhaust, and other industries. 

Over 1,500+ unique customers over 45+ years

Our reputation
stands behind every
part we ship.

API International is a manufacturer of flanges, expansion joints, valves, other pipe fittings and custom fabricated parts. We offer a wide variety of AIS imported flanges along with other industrial pipe fitting and accessories. Customers turn to us when project deadlines are tight, parts are hard to find, and they need fast shipping plus expert support to keep their operations on track.

99.5% order accuracy rate

120+ unique markets

10k+ individual orders a year

575,000+ flanges shipped per year

18,000+ custom products a year

Expansion Joints

Fittings & Accessories

Explore Custom Machining

Our Process

Define Customer Requirements

We begin by understanding your goals, whether it's reducing cost, improving quality, or launching a new product. Together, we define technical and commercial requirements to ensure full alignment from the start.

Global Manufacturing Capabilities

With worldwide manufacturing resources, API International provides both standard and custom flange solutions. Our network of facilities and in-house expertise allow us to deliver the right fit for your needs, whether it’s off-the-shelf or built to specification.

Collaborative Development

Our engineers work closely with customers to refine designs, reduce costs, and ensure manufacturability. We stay connected with your team throughout to keep progress clear and efficient.

Approval & Launch

After final review of samples, production begins. Our team oversees quality and delivery coordination to ensure smooth execution and traceability from start to finish.

AWWA | ANSI | ASME | DIN

The Flange Experts

Industrial Steel Flanges, Expansion Joints, Pipe Fittings & Custom Machined Parts

Our product line includes a full range of industrial flanges, expansion joints, and precision pipe fittings engineered for demanding applications. We manufacture to AWWA, ANSI/ASME and DIN standards, delivering solutions for waterworks, HVAC, oil & gas, marine, mining, agriculture, and other industries requiring durability and precision. With in-house machining capabilities, we create custom steel components to exact specifications, ensuring a perfect fit for your project while meeting strict quality standards and delivery timelines.

What Our Customers Are Saying

FAQ's

Everything you should know about us

What does API International specialize in?

API International provides high-quality components for waterworks, industrial applications, HVAC, and agriculture with a focus on timely delivery, customization, and customer service.

Most in-stock items ship same-day/next-day to meet your deadlines. Custom orders may vary depending on complexity, but we prioritize on-time delivery.

Yes. Our technical advisors are available to help you choose the right components for your application. Reach out via our contact page or call us directly.

Contact our customer service team with your order number and issue details. We’ll work quickly to resolve the matter and ensure your satisfaction.

Simply complete our New Customer/Credit Application form, available by request. Once approved, you’ll be able to receive orders from API International.

All sales are subject to API International’s standard warranty and terms which can be found here: Terms and Conditions

Yes. Contact your Account Manager for training materials.

We combine deep technical knowledge, high levels of inventory, fast delivery, and a commitment to customization and service. Our team takes ownership of every order to ensure satisfaction.

Absolutely. Our engineering and product teams collaborate with customers to design and deliver custom components that meet exact specifications.

Call or email us info@apiint.com / 503.692.3800 with your needs. Our team will be more than happy to guide you through the technical process and work with your engineers.

About API International

Not all flanges are made the same

At API International, our custom manufacturing capabilities set us apart. With an in-house machine shop, we transform your designs into precision parts quickly. From single prototypes to full production runs, we deliver cost‑effective pricing, dependable performance, and rapid turnaround. Flexible material options and rigorous quality checks ensure consistency from part to part.

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The 4 Advantages
of API

Tested, Trusted,
Proven

99.5% order accuracy rate
Our boots-on-the-ground approach ensures close collaboration with our suppliers. Every flange, valve, and fitting undergoes rigorous inspection and thorough documentation, ensuring consistent performance and reduced field issues.

Delivery You Can
Count On

Active customers in all 50 states + Canada and Mexico
When your schedule is on the line, knowing our U.S. warehouses are stocked and orders ship same-day gives you peace of mind, so you can focus on the task at hand, not the clock.

Your Specs, Our Precision

700+ machined-to-spec parts created each year
Collaborate directly with our engineers to bring your unique specifications to life, ensuring every component performs as if it were built with your project in mind.

Personalized Support

1,500+ unique customers served over 45+ years
Our dedicated account team partners with you from quote to delivery, answering questions and offering expert advice so you can make confident decisions and avoid costly delays.

Why Industry
Experience Matters

At API International, our commitment to engineered precision, collaborative problem-solving, and rigorous quality assurance helps reduce your total cost of ownership. We streamline manufacturing workflows, eliminate errors, minimize design revisions, and ensure product dependability, delivering integrated solutions that save you time, money, and operational stress.

Learn more about our products and applications

Blogs & API Resources

Building Lasting Partnerships

Every interaction is handled with care, urgency, and a genuine commitment to helping you succeed.
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