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.
“API International is both very timely and responsive to customers while providing excellent customer service, great quality products, and fostering and maintaining excellent relationships with their customers.”
“Fantastic customer service! API International is a great company to work with, their employees are great, and their products are as well!”
“API International does a really good job of helping our company and we appreciate the partnership. API International has the ability to work with us on special project pricing and lead times.”
“We have been purchasing flanges & fittings from API International for over 25 years. Excellent customer service from management to sales staff and timely delivery has helped us to keep our customers happy.”
“API International is very quick with quotes and getting back to us on PO status. I have no complaints on my end.”
“Our service experience and company relationship with API International has been great. API International provides an excellent service experience for their customers.”
“API International has been a go to flange supplier for over 20 years. Their extremely fast order processing makes placing and receiving orders seamless.”
“Great customer service. Always a pleasure to work the guys at API International. Have been doing business with for 20 years.”
“I am happy with the responsiveness and time frame in which quotes are given. I do not have anything negative to say and think they are doing a good job.”
Common standards include:
Flanges can be welded or screwed on, depending on the type of flange and piping system requirements. When selecting a flange type, some important aspects include pressure capacity, pipe size, and intended application.
AWWA flanges are primarily used in waterworks applications and cover larger size ranges (up to 144″ in diameter) but lower pressure ratings.
ANSI/ASME B16.5 flanges are designed for industrial systems with higher pressure requirements and cover smaller diameters (up to 24″ in diameter).
ANSI / ASME B16.47 flanges cover the remaining sizes from 26”-60” in diameter.
Pressure classes are defined in AWWA as B, D, E, and F for carbon steel and as SA, SB, SD, SE, and SF for stainless steel. In ANSI/ASME pressure classes, the pressure classes are defined as 150, 300, 400, 600, 900, 1500, and 2500.
ASME / ANSI Class 150 and Class 300 are pressure classes that indicate the flange’s allowable pressure capability at a given temperature. In general, Class 300 is rated for higher pressure service than Class 150, and it typically has heavier dimensions (thicker flange, different drilling by size) to support that duty.
To order industrial flanges from API International, share your pipe size, the flange standard and class you need (for example, ANSI/ASME B16.5, AWWA C207, or DIN EN 1092 PN), your facing requirement, and the material or coating requirements. If your project has special requirements like corrosion resistance, high temperature service, sour service, or specific bolt hole drilling, include that as well. Contact API International’s experienced team and we will help you select the right flange for your application from our massive stock inventory or custom machine it.
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