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CDC CAL-VAC® Rupture Disc

CDC CAL-VAC® Rupture Disc from Valve Sales Inc.

CAL-VAC® RUPTURE DISC - CDC

Relieve ultra-low vacuum or positive pressure conditions with the highly accurate, bidirectional CAL-VAC rupture disc.

Our double-acting design allows the CAL-VAC to do the work of two rupture discs with just one installation point. It relieves low vacuum pressure (as low as 1 inwc) on one side, while slightly higher pressure is relieved from the other.

The CAL-VAC’s easy-to-clean flat seat design reduces product buildup, making it easier to meet FDA requirements.

Looking for the POS-A-SET rupture disc? Nearly identical to the CAL-VAC rupture disc, the POS-A-SET relieves ultra-low pressure in the positive direction – the inverse of the CAL-VAC’s ultra-low relief in the negative direction. Contact us if you aren’t sure which you need.

CAL-VAC® Rupture Disc Features:

Two sides to the CAL-VAC rupture disc

As system vacuum approaches the burst pressure setting on the ultra-low vacuum side, a girdle is loaded until it deflects back past a knife blade assembly in the holder. As the girdle passes the knife blade, the seal is divided in a triangular pattern to relieve the vacuum.

On the higher-pressure side, the perforated metal top section, under tension loading, relieves pressure in the direction opposite the girdle. It incorporates CDC’s seven-hole pattern at the apex of the rupture disc dome. Together, the seven-hole pattern and six pre-cut sections create a non-fragmenting design.

Additionally, the top section’s pre-punched holes provide optimum flow through the disc when relieving ultra-low vacuum through the girdle.

CAL-VAC rupture discs vs. POS-A-SET rupture discs

The difference between the CAL-VAC and the POS-A-SET is the orientation of pressure relief components. The CAL-VAC relieves ultra low-pressure in the vacuum (negative) pressure direction, while the POS-A-SET Rupture Disc relieves ultra low-pressure in the positive pressure direction.

Both designs:

  • Relieve pressure as low as 1 inwc differential
  • Are dual-acting, providing both both positive and negative pressure protection
  • Can be made to meet 3A sanitary standards when used with a sanitary fitting holder assembly
  • Provide lower maintenance costs and greater reliability compared to a valve, increasing your system productivity
  • Do not include moving parts, eliminating the possibility of mechanical malfunction

Brochure / Specs

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What our Clients are Saying

VSI has rebuilt our pressure relief valves here at [our processing plant] for several years now and I have always been very pleased with their service and quality of work. The work is always completed on time and we have had no reliability issues with the valves they’ve worked on. It’s always a pleasure working with VSI and I look forward to continuing the relationship.
- Ross A., Pulp & Paper Industry
Thank you for your genuine effort on all the work you have done for [us]. As always, thank you for the quick quotes and parts.
- Randy W., Midstream Oil & Gas Industry
VSI, sales personnel, and the service staff have always managed to step up to the plate, accept the challenges presented, and continually offer great technical support, exceeding customer relations and reliability that I’ve come to trust throughout years of valued service.
- Dereque J., Downstream Oil & Gas Industry
The entire team at VSI has always been able to meet my needs and always exceeds my expectations. I have a great relationship with both the sales and service teams they are always ready to answer technical questions and provide excellent advice on ways to solve problems in the field and are always ready with solutions no matter how obscure or unusual the problem. VSI is more than ready and able to meet all my valve needs at any given moment.
- Randall K, Downstream Oil & Gas Industry
VSI has been helpful in many ways, from greasing valves, valve repair, valve replacement, and training our guys as well. We can’t say enough about quotes, labor support, material delivery time, and billing. Aaron has helped us out of several jams over the years and we appreciate it.
- Scott M., Midstream Oil & Gas Industry
Just wanted to thank you for your dedication to [us] on getting parts and material. I can always rely on VSI.
- Roger M., Midstream Oil & Gas Industry
Thank you and your team for the quick response time and for being so proactive with helping me get my customer back up and running so quickly. I really appreciate the Knowledge and support the VSI Team gives me which ensures that we have returning customers. Again, Thank you on a job well done.
- David M, Process Control Engineering & Service Company
We appreciate the wonderful equipment and support you have given us over the years. The communication and professionalism is first class. Looking forward to that continued excellence in the future.
- Derek L, Upstream Oil & Gas Industry
Your quality service and parts help make my job a lot easier. Thank you and keep up the good work!
- Scot W., Oil & Gas Industry
Valve Sales Inc. provides outstanding service and support for all of our valve needs. Their dedication to quality and consistency allows our equipment to run more reliably and improves overall performance of our facility. Our goal is to provide consistent high performing products to our customers and VSI allows us to achieve this goal.
- Guy M., Pulp & Paper Industry
Just wanted to let you know we appreciate all you do for us. Your dedication and hard work has helped us tremendously these past few years. Thanks again!
- Jarek A., Midstream Oil & Gas Industry
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