Please look below for a list of our most frequently asked questions and their corresponding answers. If you have a more specific question or require greater detail, we encourage you to contact C.D.C. Corporate Headquarters directly or your local C.D.C. Representative.

What is a rupture disc?

Which rupture disc design should I specify?

Which rupture discs meet ASME Certification?

What's the difference between tension type and reverse acting rupture discs?

The rupture disc keeps breaking early, what's wrong?

How do I know if the rupture disc is installed correctly?

What can I do to make sure the rupture disc operates as intended?

Who is my representative?

We re-evaluated our relief system, and it no longer meets requirements. What can I do?

Why aren't rupture discs kept in stock at C.D.C.?

How do I identify my rupture discs / How do I reorder a set of rupture discs?

What is the difference between the manufacturing range and the burst tolerance?

Is my rupture disc interchangeable with other manufacturers?

I don't see what I need in the Continental Disc Corporation Catalog.

How can you verify the flow performance of my rupture discs?

Other Continental Disc Corporation features that minimize error include C.D.C.'s innovative Three-Dimensional Flow Direction Tag which is permanently attached to most rupture disc designs, and provides instant visual verification that the rupture disc has been correctly oriented into the system. The 3-D tag extends beyond the holder to insure clear visibility for easier installation and inspection after the rupture disc has been installed. A customer-supplied identification number, pinstamped on the tag, allows for easy verification of your inventory using your system numbers.

Alignment pins are installed in some rupture disc holders. Designed to mate with holes in the rupture disc, these pins provide positive alignment and assure the rupture disc is correctly oriented in the holder.

A J-Hook, welded to the rupture disc holder inlet, provides easy alignment and proper orientation relative to the flow direction. Plus, stainless steel tags, attached to the holder inlet and outlet, specify the proper flow direction.

Encapsulating rings are available for most designs. These provide a solid place for installers to hold rupture discs during installation, which is especially important for thinner rupture discs (usually with lower pressure ratings).

The best method to prevent installation problems is education in proper installation techniques. Contact the C.D.C. Corporate Headquarters or your representative to learn more about proper techniques, or about attending a technical seminar.

What can I do to make sure the rupture disc operates as intended?
Proper rupture disc operation is mostly dependent on two factors: specifying the design correctly, and proper installation. Contact the C.D.C. Corporate Headquarters or your representative if you are concerned about ensuring proper operation in your overpressure relief systems.

Who is my representative?
If the C.D.C. representative in your area has not already made contact with you, we will be happy to refer you to them. Call the C.D.C. Switchboard at 816-792-1500, or contact us for a referral.

We re-evaluated our relief system, and it no longer meets ASME Code relieving requirements. What can I do?
Our rupture disc designs each have different certified flow resistance values. A newer rupture disc design or a different configuration may allow for greater relief capacity. In some cases, simply using the certified value (rather than an industry standard estimate) can show that an existing system meets new requirements. Check out our CERTIFLOW™ literature to see if using our certified flow resistance values can help you meet your requirements.

Why aren't rupture discs kept in stock at C.D.C.?
The variety of rupture disc configurations (size, pressure, temperature, material, linings, holder design, options) prevent C.D.C. from maintaining stock on all rupture discs. Each lot is made to the customer's particular specifications. This is one reason why rupture disc prices may change from one order to the next; issues like lot quantity and material cost have greater importance when the product is built to order.

How do I identify my rupture discs / How do I reorder replacement rupture discs?
Every rupture disc lot made by Continental Disc Corporation is traceable; the Manufacturing Number (pinstamped on the 3-D Tag or on the device) tells C.D.C. everything about that rupture disc, right down to the particular roll of metal it was made from. Supplying C.D.C. with the Manufacturing Number insures that your new order will conform to the specifications of the previous one. Care should be taken, however, that your process environment has not changed since the last order. For example, if the process temperature was increased 100 degrees Fahrenheit since the last order, the rupture disc materials you are reordering may be inappropriate and should be ordered to correct requirements. C.D.C. will stamp any customer-supplied tag number on the 3-D tag, but the C.D.C. Manufacturing Number (also on the tag) is what we use to trace a lot of rupture discs.

What is the difference between the manufacturing range and the burst tolerance?
According to the ASME Code, Section VIII, Division 1:

The Manufacturing Design Range is a range of pressure within which the marked burst pressure must fall to be acceptable for a particular requirement as agreed upon between the rupture disc manufacturer and the user or his agent.

Simply put, the Manufacturing Range is the range of pressure in which a rupture disc's marked rating must fall, in order to be accepted by the customer.

The Burst Tolerance is the acceptable range in which a rupture disc might be expected to burst. ASME code specifies a Burst Tolerance of +/- 5% for burst pressures 40 psig (2,8 barg) and above, and +/- 2 psig (0,14 barg) for burst pressures below 40 psig.

In summary: the Manufacturing Range applies during the manufacturing process; Burst Tolerance applies to the marked burst pressure after the manufacturing process is done.

Some of our rupture disc designs are available with a ZERO manufacturing range: the burst pressure you specify will be exactly the burst pressure marked on the tag. See the individual product bulletins for details concerning Manufacturing Range, Burst Tolerance, and Zero Manufacturing Range rupture discs.

Is my rupture disc interchangeable with other manufacturers?
Many rupture discs use special holder designs, or patented features which make interchangeability with other manufacturers' holders impossible. Additionally, for installations which require adherence to ASME Code, the certified flow resistance is valid only for that combination of rupture disc and holder which was tested by the manufacturer and certified by The National Board of Boiler and Pressure Vessel Inspectors. Contact the C.D.C. Corporate Office or your representative for interchangeability in non-ASME Code installation.

I don't see what I need in the Continental Disc Corporation Catalog.
Continental Disc Corporation has built a 35-year reputation for solving the toughest pressure relief problems. Solving pressure relief problems for you is the special role played by C.D.C.'s Product Development Group and the Special Products Group. This pool of product development expertise has been retrofitting C.D.C. designs into clients' systems for more than 35 years. C.D.C. is ready to solve your special pressure relief problems. Contact the C.D.C. Corporate Office or your representative to find your solution.

How can you verify the flow performance of my rupture discs?
Continental Disc maintains an ASME Flow Test Laboratory operated by a team of experienced research and development personnel who are ASME accepted authorized observers. With the addition of the new Liquid Flow Loop, the Flow Test Laboratory can now run the full gamut of flow tests in both air and liquid.