Delivering Diamond Quality

(361) 572-4040

Commitment to Quality

Incredible attention to detail is the cornerstone of our custom designed quality assurance program. Quality materials, expert certified fabricators and rigorous testing... that is the Diamond difference.
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Field Services

Our certified fiberglass professionals are available to assist your organization with on-site field services. Let our team provide peace of mind that your vessels are functioning the way they were designed.
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If every picture tells a story, these speak volumes about Diamond's experience, expertise, dedication to quality and our ability to execute to your exacting specifications.
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Fiberglass Reinforced Plastic (FRP) Tanks by
ASME RTP-1 Certified Fabricators

Custom Fiberglass Reinforced Plastic TankDiamond Fiberglass manufactures custom engineered Fiberglass Reinforced Plastic (FRP) tanks and vessels. After four decades in the fiberglass tank fabrication business, we've built a quite a few tanks. More importantly, we've built an incredible reputation by engineering, fabricating and delivering the highest quality tanks and vessels in the industry today. 

Experience, Expertise, Execution

It starts with a professional team dedicated to meeting the unique needs of each customer. We work closely with each client to understand the needs of the project, the end user and industry. Projects are then handed to our in-house design and engineering team. Our engineers work closely with the project fabricators and quality assurance team to make sure that each step of the process meets the exacting design standards From the initial concept design to a finish project delivered to your facility, on schedule, you can count on Diamond Fiberglass to meet your needs every step of the way. 

ASME RTP-1 Certified Fabricator

ASME RTP-1 Certificate of AuthorizationDiamond Fiberglass is an ASME RTP-1 certified fabricator. Only certified fabricators are able to design, fabricate and stamp fiberglass vessels. Diamond Fiberglass has worked hard to achieve the ASME RTP-1 certification, which is the most comprehensive standard in the fiberglass industry for reinforced thermoset plastic vessels. Each year, third party audits are conducted by ASME and internal audits by our ASME RTP-1 program's Certified Individual ("CI"). Every three years, Diamond's entire program is recertified through an independent third party. 

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Diamond Fiberglass is proudly celebrating its 30th year of quality, custom engineered Fiberglass Reinforced Plastic (FRP) tanks and vessels. Thanks to everyone who has made this possible.