Selecting Burst Rating for Rupture Discs

Rupture disc application requires knowledge of process
operation and compliance requirements.
Image courtesy Continental Disc Corporation

Three rating types are available to specify the burst pressure requirements of a Continental Disc Corporation rupture disc:

• RATED
• SPECIFIED
• MIN/MAX

The embedded document below defines and describes each rating type.

For more information on Continental Disc rupture discs, contact CTi Controltech. Call them at 925-208-4250 or visit their web site at https://cti-ct.com.

Rupture Disc Burst Rating Types from CTi Controltech

Rupture Discs for Sanitary and Hygienic Applications in Pharmaceutical, Biotech, Food, and Beverage Facilities

Continental Disc Corporation's SANITRX HPX & SANITRX HPX II Rupture Discs are semicircular scored reverse acting rupture discs designed specifically for the pharmaceutical, biotech, food and beverage industries. These rupture discs are available to fit between industry standard sanitary ferrules, NA-CONNECT® flanges or SANITRX fittings.

The SANITRX HPX & SANITRX HPX II Rupture Discs can be used in a wide range of sanitary and hygienic applications throughout pharmaceutical, biotech, food, and beverage facilities. The following list is only a small sample of the many ways in which this outstanding rupture disc can be used:

• Autoclaves
• Bioreactors
• Clean Steam Piping 
• Process Vessels 
• Heat Exchangers 
• Filters
• Storage & Transport Vessels
• Mixing, Drying, Granulating Equipment 
• Wfi Vessels & Piping
• Lyophilizers (Freeze Drying)
• Cip & Sip Skids and Piping
• Fermenters

To learn more about sanitary and hygienic rupture discs, review the embedded document below or download a PDF of the Continental Disc Corporation Sanitrx HPX & Sanitrx HPX II Rupture Disc brochure here.

Sanitrx HPX & Sanitrx HPX II Rupture Discs from CTi Controltech

Convenient Rupture Disc Selection Form from Continental Disc Corporation

CDC rupture disc.

Continental Disc Corporation is a leading manufacturer of rupture disc (bursting disc) devices for a variety of process industries, including chemical, petrochemical, petroleum refining, pharmaceutical, food and beverage, aerospace, industrial gases, transportation, and other markets worldwide.

They have a very convenient online form to assist in replacement of an existing rupture disc, or to specify a new installation. The form can be found by following this link. The form gives you the option to print it from its online page, or to email the form to Continental Disc sales department for a quotation.

In 2017, CTi Controltech was appointed the exclusive Continental Disc and Groth Equipment representative in Northern California and Nevada.

Rupture Disc Assemblies Designed to Protect Tanks Against Implosion or Overpressure Conditions

CAL-VAC and POS-A-SET

Continental Disc Corporation's CAL-VAC^® and POS-A-SET^® Rupture Disc Assemblies are highly accurate, double acting pressure relief devices designed to protect processing and storage tanks against implosion or overpressure conditions that can occur in:

• Positive Pressure - overfill, external fire, steam regulator failure 
• Vacuum Relief  - liquid pump out, insufficient flow through sanitary vent filer, flash vacuum due to CIP cool rinse, primary vent malfunctions, blanket gas or air regulator failure

Both designs relieve pressure settings starting as low as 1 InWC (inches water column) differential. The difference in the CAL-VAC Rupture Disc and POS-A-SET Rupture Disc is the orientation of the components to meet the relieving requirements. The CAL-VAC Rupture Disc 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.

Contental Disc CAL-VAC® and POS-A-SET® Rupture Disc Assemblies from CTi Controltech

Combining Rupture Discs With Pressure Relief Valves

Applying a rupture disc in concert with a safety relief
valve can deliver real benefits.
Image courtesy Continental Disc Corporation

Common elements of any pressurized system include safety and pressure relief valves. Their general purpose is to stop system pressure from exceeding a preset value, preventing uncontrolled events that could result in damage to personnel, environment, or assets. Their operating principle and construction are comparatively simple and well understood.

Long term exposure of a relief valve to process media can result in corrosion, material buildup, or other conditions which may shorten the useful life of the valve, or worse, impair its proper operation. This excessive wear will increase the ongoing cost of maintaining or replacing a prematurely worn valve. One other aspect of relief valves can be the reduction in their seal integrity or force as the system pressure approaches the setpoint. This could possibly lead to fugitive emissions, an undesirable condition.

An effective approach to mitigating some of the effects of exposure to the process media is to install a rupture disc upstream of the safety valve inlet. Isolating a relief or safety valve from the process media through the installation of a rupture disc upstream of the valve inlet will eliminate exposure of the costly valve to effects of the media. It is necessary to establish proper rating and selection for the rupture disc to avoid any impairment of the overall operation of the relief valve, but the selection criteria are not complex. A number of benefits can accrue with this concept.

• Rupture disc isolates the valve from the media, allowing application of less costly valves fabricated of non-exotic materials.
• Rupture discs are leak free and bubble tight, eliminating possibility of fugitive emissions from the safety relief valve, especially when system pressure may approach valve setpoint.
• Relief valve inventory can be evaluated for reduction.
• Longer valve life.
• Less downtime.

The additional cost for the rupture disc enhancement can have a reasonable payback period, with all factors considered. In any case, the rupture disc protection makes for a cleaner relief valve installation. The document provided below provides some additional application recommendations and details.

Rupture discs and holders are available in sizes and materials for most applications. Share your ideas with a product specialist, combining your process knowledge with their product application expertise to develop an effective solution.

Combining Rupture Discs and Safety Relief Valves from CTi Controltech

Rupture Discs - Designed to "Fail"

Rupture discs can be combined in series for additional functions.
Image courtesy Continental Disc Corp.

A rupture disc, sometimes known as a pressure safety disc, burst disc or bursting disc, is a one time pressure relief device most often used to protect a vessel, pipe, or container from over pressurization. As opposed to pressure relief valves, rupture discs are designed to function only one time by providing an instantaneous response to an over-pressure condition, providing sufficient venting flow to disallow any further pressure increase.

These sacrificial parts are designed to burst when pressure within production equipment exceeds a certain threshold by breaking down, stopping the process to prevent or mitigate hazardous events. Rupture discs are critical instruments utilized so that companies can ensure process safety as set forth by the International Safety Standards (IEC 61508/61511).

The safety devices prove most effective when they fail according to pre-established specifications. Inferior rupture discs may cause unnecessary and expensive production shutdowns by bursting at the wrong pressure. Adequate quality testing and manufacturing expertise assures performance in accordance with ratings.

Rupture discs are commonly used in chemical, petrochemical, nuclear, aerospace, medical, railroad, pharmaceutical, food processing and gas & oil applications. They provide primary or backup protection. Very often rupture discs are used in tandem with safety relief valves, protecting them from the process media and extending the life of the relief valve.

For more on rupture discs call CTi Controltech at 800-288-7926 or visit their website.

Rupture Disc Products For Industrial Process Safety from CTi Controltech