How can we help?

Since all U.S. domestic sales are coordinated through a factory trained sales representative organization the best customer service can be acquired through your local sales representative.

Visit www.bsbsystems.com or call (918) 622-5950. States have been divided into sections according to the local representative. Pick the one that is closest to the area you are calling from.

Some disk pricing is quantity sensitive.

There is no recommended time for a disk to be replaced. User experience is the best teacher. For example, if you find a trend that your disks rupture after a period of 6 to 8 months in service, to avoid costly down time, it may be suggested to change the disks out every 5 months. BS&B offers a service to assist in the customer’s determination of a disk’s service life so you may optimize service life of the disk without the worry and hassle of change out. We stand ready to test unburst disks removed from service.

In general, most tension-loaded or conventional style disks require a vacuum support to withstand full vacuum. Reverse buckling disks will "withstand" or (resist) full vacuum without the use of a vacuum support. (Refer to catalogs for specific products). A common exception for reverse buckling disks is the type ECV™, which requires a vacuum support to allow the disk to withstand full vacuum. Vacuum resistance is the maximum vacuum that a disk is rated to hold. This is not the same as burst pressure.

Every order is supplied with Installation Instructions for proper installation. In general, the sensor is placed between the outlet flange of the holder and the downstream companion flange. For specific instructions please request the Installation Instructions for the specific product type.

BS&B does not take responsibility for sizing a customer’s application. We will assist in sizing applications using a Size-Saf program that is available for the customer’s use. But it is the responsibility of the customer to determine the parameters for correct disk sizing. (Refer to Catalog 77-1005 Section B).

BS&B engineers are available to discuss specific applications. Consult the factory. The following information is required to specify a BPRV™ unit.

1. General: Tag number, Line size, Flange specification, Inert Type or Full Bolted.
2. Service Conditions: Fluid, Vapor, Gas or Liquid, Molecular weight, Specific gravity, Flow capacity required, Normal service pressure, Vacuum conditions, Normal service temperature, Flowing temperature, Back pressure conditions, Static or Pulsing service pressure.
3. Operating Conditions: Set pressure, Tolerance, Set temperature (external environment).
4. Materials: Vent plug, Vent body, Seal, Enclosure
5. Installation: Vertical, Horizontal, Oblique
6. Accessories: Enclosure, Vented or Sealed, Locking type, Signal switch, Switch code requirements. (Refer to Catalog 77-1015 Section B).

Klinger®-Sil is a compressed fiber, non-asbestos gasket material. BS&B uses Klinger®-Sil C-4401 for standard alert sensor gasket material and on Graphite and type AV disks.

Most competitor’s products can be identified and cross-referenced by the nomenclature used for the various types of disks and holders.

Although some people specify rupture disks at the process temperature, disks should be specified at the temperature to which the disk will be exposed when it is required to rupture. BS&B does elevated temperature testing to ensure the rupture disks they provide will rupture at the customer’s specified pressure/temperature request.

ASME Code requires UD certified rupture disks for all new construction subsequent to January 2, 1999, regardless of the application.

This depends on the type of rupture disk and pressure.

A damper disk is not a pressure containing device, but rather, a perforated metal membrane installed upstream of a rupture disk designed to absorb and dissipate energy from pressure "spikes".

Pounds per square inch differential.

BS&B has a training specialist who conducts "on site" training of plant personnel who are involved with the selection, installation, and use of rupture disks. The training fully satisfies the requirements of OSHA 29 CFR 1910.119. Certificates of satisfactory completion are provided to attendees for training files.

Yes! Contrary to the sales rhetoric of some manufacturers, installing a rupture disk with the manufacturer’s recommended torque can significantly improve the rupture disk’s precision and service durability. Although some disks are more forgiving of improper or unbalanced torque, each is an instrument and should be installed with proper torque.

Clearly the best advice we can offer is to be fully rupture disk "literate". Due to the complexity of the products, that is not always easy. BS&B offers "no charge" engineering and technical seminars to educated personnel on rupture disk technology and disk selection. Additionally, we encourage you to contact our factory-trained sales representatives or the factory for assistance. We are pleased to help.

Certainly the condition of the disk and its proper installation may influence disk service life but quite commonly, the disk is being exposed to pressures that exceed the "maximum operating pressure" of the disk. Some disks are designed to be exposed to system pressures no more than 50% of the marked burst pressure of the disk. Others may be exposed to 90% of their marked burst pressure with only negligible metal fatigue. Exposing a disk to pressures in excess of their designed "maximum operating pressure" (expressed as a percent of the marked burst pressure) can dramatically reduce service life. Should you believe you are not getting the service life you need from your rupture disk, we would be pleased for the opportunity to discuss your service environment and perhaps, recommend a disk design that would offer you longer service. Remember that proper installation can also significantly influence disk service life.

In many instances disks for a variety of applications may be consolidated. Certainly size is a prime consideration. Secondly, material of construction is important. In many instances, two disk applications currently manufactured from Alloy 600 and Alloy 400 may be satisfied with a common disk manufactured from Alloy 600. A disk such as the BS&B Type SKR™ can be used in both liquid and vapor service reducing the need for disks of two different descriptions for different service conditions. BS&B would be pleased to offer assistance.

We recommend the practices defined by the ASME Code and API. The rupture disk and the relief valve should be "close coupled" (No intervening spool piece). The disk and relief valve should be set at the same nominal pressures. The cavity between the rupture disk and the relief valve must be monitored to ensure there is no pressure in the cavity. Since rupture disks are differential pressure devices, any pressure downstream of the rupture disk is considered a "back pressure" and will prevent the disk from opening at its marked burst pressure. See specific details on the Code or request assistance from your local BS&B factory-trained sales representative.

A "safety head" is the BS&B nomenclature for a rupture disk holder. The ASME Code defines a "rupture disk device" as a rupture disk and the holder into which the disk is installed. The "safety head" is the portion of the device which ensures the proper performance of a rupture disk and accommodates its installation into a piping scheme.

Burst tolerance is the allowable deviation in actual burst pressure from the "marked burst pressure". Typically expressed as a percentage (or in "psig"), a disk properly specified and installed should always burst within the "tolerance" for the particular type, style, and rated pressure of the disk.

"Manufacturing design range" is a "premanufacturing agreement" between BS&B and the customer for "economy". It is a "range" of pressures within which the marked burst pressure of a lot must fall. If a customer requests a 100psig rupture disk with a manufacturing design range of 10%, the customer is allowing BS&B to provide to him, a lot of disks, the marked burst pressure of which, must be between 90psig and 100psig. Should the customer request a 5% manufacturing design range, BS&B would be obligated to provide a lot of disks which must have a marked burst pressure anywhere between 95psig and 100psig. Manufacturing design ranges may be indicated as a percentage or in psig. Should the customer request to received a lot of disks marked precisely at his requested pressure, a 0% (zero percent) manufacturing design range would be requested.

The "maximum operating pressure" is the maximum system pressure to which the disk may be exposed without causing premature metal fatigue to the rupture disk. If a particular style of rupture disk rated at 100psig has a 90% maximum operating pressure, the disk should not be exposed to greater than 90psig. Maximum operating pressures are typically between 50% and 100%. Exposing a particular style of disk to greater than the manufacturer’s published maximum operating pressure can significantly shorten the service life of the disk.

Also called a "compression-loaded" rupture disk, a "reverse-buckling" rupture disk is one which is installed with the crown of the disk (convex side) facing the system pressure.

Typically reverse-buckling rupture disks are significantly more service-durable than forward-acting (tension-loaded) rupture disks. Most have a maximum operating pressure of 90% (can be exposed to system pressure up to 90% of their marked burst pressure). Almost all reverse-buckling rupture disks are designed for non-fragmentation which makes them most ideally suited for isolation of relief valves from the process environment.

Some rupture disk holders are held together by "assembly lugs" on the side of the holders until they may be installed into the piping scheme between companion flanges. A "pre-torqued holder" is equipped with recessed capscrews which not only hold the two halves of the holder together but also provide a precise mechanism with which to apply the manufacturer’s recommended torque value to the disk. The disk and holder (rupture disk device) may be precisely assembled in the convenience of the maintenance or instrument shop assuring proper performance of the disk device in service.

Yes. The ASME Code recognizes the use of a rupture disk as a primary relief device.

Yes. Depending upon the style of disk selected, a wide variety of sensors (and sensor monitors!) are available. Additionally, BS&B manufactures a special "leak detector sensor" to assist in determining if a rupture disk is leaking either due to improper installation, corrosion, or erosion.

Several answers apply to this question. First, should the rupture disk protecting a relief valve from the process not rupture from exposure to excess process pressures, the relief valve is maintained in a clean, pristine condition. Valve maintenance costs are, accordingly, dramatically reduced. Second, isolation of relief valves with rupture disks is environmentally smart. The "bubble tight seal" of a rupture disk prevents valve leak, seep, weep, and chatter. For more details on the advantages of relief valve isolation, see BS&B Catalog #77-1006.

"SAF" (Structural Apex Forming) technology is a state-of-the-art design and manufacturing technology in which the crown of a disk is precisely "pre-weakened" in the manufacturing process. In addition to providing a manufacturing variable for precision burst pressure control, it also typically allows rupture disks to be made of heavier materials to minimize the possibility of damage to the disk in handling and installation.

When a rupture disk is used to isolate a relief valve from the process environment, the ASME Code requires the cavity between the rupture disk and the valve seat to be monitored. Since a rupture disk is a "differential" pressure relief device, any pressure in the cavity between the rupture disk and the relief valve seat will act to elevate the burst pressure of the rupture disk. A "tell-tale" assembly is a method to satisfy this Code requirement. Other methods may also be used to fulfill this requirement. (See ASME Code)

NO! Consult BS&B catalog literature or contact your local factory-trained sales representative for specific service applications for which disks may be used. BS&B does offer a broad scope of rupture disks which are suitable to both gas and liquid applications. (See literature on the Types "CSR", "SKR", and "RLS" rupture disks).

Although the scope of this question is a bit broad for a brief answer, rupture disks are custom-manufactured, engineered safety devices. The methods of manufacture typically involve type of disk, size of disk, material of construction, material thickness, crown height, score depth (if a scored disk) and often, material thermal treatment (annealing or stress relieving). Depending upon the "style" of rupture disk, some or all of the variables indicated may be adjusted to provide the disk requested. During the manufacturing process, as variables are adjusted, many test breaks (destructive testing or "finding breaks") are done to determine the best combination of variables to provide a disk with the best precision and service durability.

"MAWP" is the acronym for "Maximum Allowable Working Pressure". According to "Code", rupture disks used as primary system pressure relief should not have a marked burst pressure in excess of the system "MAWP".

This answer to this question is really at the discretion of the user. A rupture disk specified at the system MAWP will typically provide the longest possible service of that particular style of disk (since its marked burst pressure is as far from the system pressure as possible). Some prefer an extra "margin of safety" between the marked burst pressure of the rupture disk and the MAWP and request the disk to be rated less than the MAWP.

Division I, Section VIII of the ASME Code is the portion of the ASME Code which most commonly applies to rupture disk applications, sizing, selection, and installation for unfired pressure vessels. Other portions of the Code also address rupture disk use in more diverse applications (such as nuclear applications).

BS&B has its own "Flow Lab" for testing flow coefficients of our products to obtain ASME/UD certification from The National Board. Please contact BS&B sales support for a specific style, size, and specified operating media to determine if a particular disk has UD certification.

For disks, the burst certificate, mill certificate, or certificate of conformance are free. There is a charge for mill certificates for holders and ASME certifications.

A previous "Lot Number".

You can locate your Lot Number on an old invoice or on the tag of the old rupture disk you are replacing.

Lot numbers allow BS&B to duplicate previous order specification. BS&B lot numbers are composed of 8 digits followed by an item number. Very old lot numbers are composed of 6 digits. Contact the representative in your area, or you may call the factory for lot number identification.

BS&B understands that sometimes customers need expedited delivery for a particular order. We have a Premium Department to handle emergency orders. Since all rupture disks are custom-manufactured, there is a cost associated with this service. Therefore, it is imperative for both the customer and BS&B to understand what is needed and when. This helps coordinate Sales, Manufacturing and Shipping to get the disk into the customer’s hands exactly as requested and prevents costly mistakes to the customer and BS&B. Contact the sales representative in your area, or call us direct.