BIO-SAF System^TM

• One disk design for gas and liquid service
• Fail-safe design - Damage-Safety ratio less than or equal to 1
• Low to high Burst Pressures
• Ideal for CIP/SIP Service*
• Installed with Integral Sanitary/Aseptic Gaskets
• 8 to 16 micro-inch typical disk surface finish
• Minimum dead space between process fluid and the disk
• Suitable for operating pressures up to 90% of Marked Burst Pressure** or 95% of the specified minimum burst pressure (CEN standard pending)
• Designed for non-fragmentation
• Standard Manufacturing Design Range, zero%, optional - 5%, -10%
• Withstands full vacuum at all Burst Pressures
• SAS^TM (Sanitary Alert Sensor) with leak sensing option available
• Integral burst disk sensor option
• Worldwide patents pending

*Clean/Steam in Place
**At marked burst pressures of 40 psig (2.76 barg) and below, the recommended maximum operating pressure is 90% of the marked burst pressure, less 2 psig (0.138 barg) tolerance.

GCR-ST Disk Specification Min/Max Burst Pressure at 72^o F (22^o) Psig (Bar)

Design

The GCR-ST family of reverse buckling disks is designed with a circular score line located at the edge of the domed area. At the marked burst pressure the disk's dome reverses and opens by shearing around the circular score line. The GCR-ST provides very low burst pressures with excellent opening characteristics. An integral energy absorbing hinge located on the downstream side of the disk enables the disk to perform in gas or liquid service with superior flow performance. The hinge design interacts with the holder outlet bore to retain the disk on opening, avoiding fragmentation.

SAFT Technology: Damage Safety Ratio Less Than or Equal to 1

Structural Apex Forming, the precision indentation present in all GCR-S Rupture Disks, combined with the unique energy absorbing hinge design, ensures that a damaged disk will rupture at or below the marked burst pressure.

Marked Burst Pressure

The ASME Code requires that the marked burst pressure is within the manufacturing design range and is determined such that the sample burst test pressures are within the specified tolerance (+/- 2 psig at or below 40 psig or +/- 5% above 40 psig). BS&B Safety Systems, Inc. and BS&B Safety Systems Ltd. will exceed ASME code requirements by continuing to use the average of the burst test values as the marked burst pressure (for -5% and -10% Manufacturing Design Range) and requiring this average to fall within the manufacturing design range. This is in accordance with previous editions of the code and will maintain consistency in burst pressure marking for the user.

Sensors

The Sanitary Alert Sensor is for use between standard sanitary /aseptic fittings to provide warning of a burst rupture disk (bursting disc). Leaking disk detection is also available; consult BS&B Safety Systems, Inc. or BS&B Safety Systems Ltd. for details.

The GCR-ST and GCR-SMT disks are also available with integral sensors to provide warning of a burst rupture disk (bursting disc), specify types GCR-SST and GCR-SMST.

Manufacturing Design Range

Manufacturing Design Range is a range of pressures within which the marked burst pressure must fail to be acceptable for a particular requirement as agreed upon between the Rupture Disk (Bursting Disc) Manufacturer and the user or his agent.

The standard Manufacturing Design Range for the GCR-ST disk is 0%. The user's requested burst pressure will be the Marked Burst Pressure. Optional Manufacturing Design Ranges of -5% and -10% may be selected as operating conditions permit. The Manufacturing Design Range is applied to the minus side only of the requested burst pressure.

Flow Performance

Flow Resistance Factor KR may be used to determine the relieving capacity of a system according to the ASME and CEN (pending) codes. Individual KR values have been established for both gas and liquid service for the disk. Minimum Net Flow Area (MNFA) for each disk size is provided to assist with ASME sizing calculations. Net Relief Area has been provided for sizing according to European and International standards.

KR Values Minimum Net Flow Area (MNFA), NRA Values

The KR values indicated are for gas service. The GCR-ST disks have been performance tested for both gas and liquid, contact BS&B Safety Systems, Inc. or BS&B Safety Systems Ltd. for liquid service KR values. CE marking of bursting disks will be offered on completion of validation to the European Code.

Gaskets

The GCR-ST is supplied with FDA approved Silicone, Viton^® (white or black), EPDM (white or black) and Tef-Steel^® gaskets ensuring correct and leak-tight installations with type GR-CT fitting or FM-CT disk holder.

Materials

The disk is available in 316LSS as standard. Alternative materials are available on request.

Liners

Liners are available in all sizes as optional on the process side of the disk. FEP or PTFE are generally used.

GCR-ST Disk Types

GCR-ST and GCR-SST with approved gaskets are installed between a standard inlet ferrule and the GR-CT outlet fitting ensuring correct direction of disk and leak tight installation.

The GCR-SMT and GCR-SMST have a symmetric gasket configuration on both sides of the disk and fit between standard Tri-Clamp^® (or equivalent) ferrules.

The GCR-SET is installed in a FM-CT Safety Head. The inlet of the FM-CT Safety Head is welded to the vessel wall and permits the rupture disk (bursting disc) to be installed flush with the interior wall of the vessel. The space between the process fluid and the disk is minimized.

GCR-SWT is a welded ferrule assembly, the disk is welded between standard ferrules.

Installation

The GCR-ST and FM-CT holder designs ensure correct direction and leak tight Rupture Disk (Bursting Disc) installation. We recommend the assembly of GCR-ST Rupture Disks into their respective holders using a Tri-Clamp^® 13 MHHS Clamp (or equivalent) with a hexagonal nut enabling control of installation torque. The GCR-ST disk range, using SAFT technology, exhibits minimum sensitivity to changes in clamp loading on the disk induced by service temperature variations. However an adequate clamping load to maintain leak tightness must be maintained.

The type GLR-S is available in 1.5" (40 mm) nominal size for use in 1.5" GR-C fitting or FM-C/FT-C holders. The type GLR-S disk is available with burst pressures as shown below.

Type FM-C Rupture Disk (Bursting Disc) Holder

The inlet of the FM-C disk holder is welded to the vessel wall, and permits the rupture disk (bursting disc) to be installed flush with the interior wall of the vessel. As the dead leg is eliminated, the space between the process fluid and the disk is minimized. The holder is available in 316L SS; clamp 304 SS and for disk/clamp sizes 1"-3".

The FT-C Rupture Disk (Bursting Disc) Holder

The FT-C holder may be used to replace a conventional sanitary fitting "Tee" on which GFR-SE disk is installed with the advantage of minimizing the dead space between the process fluid and the rupture disk (bursting disc). The FT-C holder permits the rupture disk (bursting disc) to be located adjacent to the process flow. The self-cleaning and sweeping action of the fluid minimizes possible product accumulation on the surface of the disk. The FT-C holder is available in 316 SS , for 1" - 3" disk /clamp sizes.

The JRS-S and JRS-ST are reverse buckling disks which incorporate a teeth ring attached to the downstream side of the disk. When overpressure occurs, disk rupture is achieved by the disk reversing and opening on the teeth-ring providing full relief opening.

Features and Benefits:

• For low burst pressures.
• Excellent for gas/vapor service*.
• Operating pressures up to 90%⁺ of rated pressure.
• Designed for non-fragmentation.
• Excellent in pressure cycling or pulsating conditions.
• Withstands full vacuum without vacuum support.
• Damage ratio of 1.5 or less. If damaged when installed, it will burst at or less than 1.5 times its rated pressure.

* May be used in liquid service provided there is an adequate volume of vapor above the liquid and below the disk.

⁺ At rated burst pressures of 40 psig (2.76 barg) and below, the recommended minimum operating pressure is 90% of the rated burst pressure less 2 psig (0.138 barg) tolerance.

Manufacturing Range

Disks in sizes from 1.5" (40mm) are available with a 0%, -5% and -10% manufacturing range, and the 1" (25mm) disk is available with a -2%,-5% and -10% manaufacturing range.

* Other disk sizes and materials available on request.

FEP/PTFE liners are available on the process side of the disk in sizes from 2" (50mm) and above. Maximum temperature for FEP/PTFE is 500° F (260° C), maximum temperature for 316 SS is 750° F (399° C).

The RLS-S and RLS-ST are reverse buckling disks with a circular score-line around the circumference of the disk on the downstream side. A metal hinge is attached to the disk on the downstream side to prevent fragmentation. When overpressure occurs disk rupture is achieved by reversing and opening along the circumferential score-line providing full relief opening.

Features and Benefits

• Excellent for full liquid or gas/vapor service.
• Operating pressure up to 90% of rated pressure.
• Designed for non-fragmentation
• Excellent in pressure cycling or pulsating conditions
• Withstands full vacuum without vacuum support.
• Damage ratio of 1.5 or less. If damaged when installed, it will burst at or less than 1.5 times its rated pressure.

Manufacturing Range

The disks are available with -5% and -10% manufacturing range; 0% manufacturing range is available for certain rupture pressures and sizes.

Note: Refer to SR-C holder details on the sanitary SR-C holder specifications page below when RLS-S and RLS-ST are to be selected

Other disks sizes and materials available on request.

FEP/PTFE liners are available on the process or downstream side of the disk in all sizes. Maximum temperature for 316 SS is 750^o F (399^o C), maximum temperature for FEP/PTFE is 500^o F(260^o C).

This is a type RLS reverse buckling disk supplied with an integral sanitary gasket of FDA approved silicone, Viton or EPDM. The unique design of the gasket ensures correct and leak-tight installation with the GR-C fitting or FM-C/FT-C disk holders. The type GLR-S disk is available for burst pressure applications above 300 psig (20.68 barg) which cannot be met by the type GFR-S disk. It is available in 1 1/2" (40mm) size. It is available with an FEP/PTFE liner which covers the disk and gasket on the process side.

Sanitary SR-C Holder Specifications

The D-ST composite rupture disk (bursting disc) consists of a domed slotted metal top section and a plastic or metal seal located on the concave or process side of the top section.

Features and Benefits

• Excellent for liquid or gas/vapor service
• Operating pressures up to 80% of rated pressure.
• FEP/PTFE liner provides a seal and corrosion resistance.

Type DV-ST* Disk

When vacuum is present, the disk is fitted with a vacuum support and a DV-ST type disk must be specified.

Type DD-ST* Disk

The type DD-ST may be used where two-way relief is required. This disk consists of two slotted metal sections with a plastic seal that floats between both sections. The burst pressure in one direction may be up to twice the burst pressure in the opposite direction with full relief opening in both directions when bursting occurs. The available burst pressures are the same as those of the equivalent size D-ST disk, and has identical performance features.

* The DV-ST and DD-ST construction may not be suitable for all sanitary applications, consult BS&B. 

Manufacturing Range and Burst Tolerance

Features and Benefits

• For low burst pressures.
• Operating pressures up to 60% of the minimum burst pressure.
• FEP/PTFE seal.

Burst Pressure Range

All AV-ST* type disks are marked on the disk tag with a minimum/maximum burst range. In the case of a requested burst pressure up to 25 psig (1.72 barg) the burst range will be ± 1.25 psig (0.09 barg) of the requested burst pressure, and above 25 psig (1.72 barg) ± 3 psig (0.21 barg). The manufacturing range and burst tolerance are included in this minimum/maximum burst range.

Example: Type AV-ST burst range minimum 6 psig (0.41 barg)-maximum 8.5 psig (0.59 barg) at 72^o F (22^o C), 3 inch (80mm).

Standard holder material is 316 SS with 304 SS clamp.

The VKB rupture disk (bursting disc) is a two-way acting disk designed to prevent implosion under vacuum or overpressure. The disk may be used in either gas or liquid service. The VKB rupture disk (bursting disc) installed in the KB-C holder meets the requirements of the American 3A sanitary standards.

Vacuum Relief

At the rated vacuum relief pressure the disk seal separates from the perforated metal section to snap against a set of knifeblades located in the disk holder inlet cutting the seal into three segments. The perforated metal section remains intact, and flow through the holes in the metal section relieves the vacuum.

Burst Range 

The disks are available with a burst range of +/-1.5 in WC (3.75 mbarg) for pressure up to 8.0 in WC (20 mbarg) and  +/- 20% for higher pressures. All tolerances are included in the burst range. Example: a disk with a specified vacuum relief pressure of 7.0 in WC (17.5 mbarg) will be marked on the disk tag as minimum 5.5 in WC (13.75 mbarg) - maximum 8.5 in WC (21.25 mbarg).

Overpressure Relief

The disk relieves overpressure by opening fully along the metal slits in the perforated section. The disk offers a smooth surface towards the process which prevents product accumulation.
 

The disks are available with a +/- 2 psig (0.138 barg) or minus 10% manufacturing range depending on the burst pressure.

Example: A burst pressure of 58 psig (4 barg) is requested with a 10% manufacturing range. The values of the burst tests carried out during manufacture will lie between the 52.2 psig (3.6 barg) and 58 psig (4 barg). The average of  the test values will be marked on the disk tag.

Burst Tolerance

Operating Pressure                                                                                   

The rupture disks (bursting discs) may be subjected to the following operating pressures without affecting the disk's service life.

Vacuum Relief: up to 80% of the minimum of burst range.

Overpressure Relief: up to 80% of the tagged burst pressure.

Type P/VKB Rupture Disk (Bursting Disc)

Type P/VKB rupture disk (bursting disc) is a two-way acting disk designed to relieve light overpressure or prevent implosion under vacuum. The disk may be used in either gas or liquid service. The type P/VKB is the inverted style of the type VKB disk.
 

Overpressure Relief

Burst Range

The disks are available with a burst range of +/- 1.5 in WC (3.75 mbarg)   for pressure up to 8.0 in WC (20 mbarg) and       +/- 20% for higher pressures. All tolerances are included in the burst range. A disk with a specified burst pressure of 16.0 in WC (40 mbarg) will be shown on the disk tag as minimum 12.8 in WC (32 mbarg) - maximum 19.2 in WC (48 mbarg).

Operating Pressure

The system may operate up to 80% of the minimum of the burst range without affecting the service life of the disk.

Vacuum Relief

The disk may be used also to relieve vacuum depending on specific requirements.

Asymmetric alignment pins in the holder mate with locating holes in the rupture disk (bursting disc) for proper installation. The standard holder material is 300 series stainless steel, the knife blade material 301 SS.

Type AVB-ST & P/AVB-ST Two-Way Relief Disks

The type AVB-ST rupture disk (bursting disc), like the VKB disk is a two-way acting disk designed to prevent implosion under vacuum or overpressure. This disk meets the medium range vacuum and overpressure relief requirements that cannot be met by the VKB disk.

Vacuum Relief
Burst Range

T'he disks are available with a minimum/maximum burst range which includes the manufacturing range and burst tolerance.  A 4" (100mm) disk with a  specified vacuum relief pressure of 5 psig (0.34 barg) will be marked on the disk tag as minimum 4.5 psig (0.31 barg) to maximum 5.5 psig (0.38 barg).

Overpressure Relief
Manufacturing Range

The disks are available with a 0%, -5% or -10% manufacturing range. If a disk is ordered with a 50 psig (3.45 barg) burst pressure and -10%  manufacturing range, it will be tagged at a burst pressure between 45 psig (3.1 barg) and 50 psig (3.45 barg).

Burst Tolerance
Tolerances are the maximum variation from the rated burst pressure shown on the tag.

Operating Pressures

The rupture disks (bursting discs) may be subjected to the following operating pressures without affecting the disk's service life.

Overpressure Relief:  up to 70% of the disk's tagged burst pressure.
Vacuum Relief:          up to 60% of the minimum of the burst range.

The P/AVB-ST disk is the inverted form of the type AVB-ST disk, and meets the medium range of overpressure and vacuum relief requirements that cannot be met by the P/VKB disk.

Overpressure Relief

Burst Range

The disks are available with a minimum - maximum burst range which includes the manufacturing range and burst tolerance. A 3" (80mm) disk with  a specified burst pressure of 7 psig (0.48 barg) will be marked on the disk tag as minimum 6.5 psig (0.45 barg) maximum - 7.5 psig (0.52 barg).

Operating Pressure

The system may operate up to 60% of the minimum of the burst range without affecting the service life of the disk.

Vacuum Relief

The disk may be used also to relieve vacuum depending on specific requirements.

VB-C and P/VB-C Holders

Assymetric alignment pins in the holder mate with locating holes in the rupture disk (bursting disc) for proper installation. The standard holder material is 316 SS.

VSP & VSE Explosion Vents

Explosion vents protect against damage in the event of deflagrations of combustible materials. These explosion vents of single section steel construction are supplied with a smooth internal surface finish. Solid white silicone gaskets are fixed to the vent flange area and FDA approved RTV sealing material applied to the vent perimeter to achieve a sanitary/aseptic construction.

The vents are available in a wide range of sizes in either circular or rectangular designs. For more information, see catalog 77-8015.

Typical equipment protected includes silos, spray dryers, dust collectors conveyors.

SAS Sanitary Alert Sensor

The SAS Sanitary Alert Sensor provides immediate warning of a ruptured disk when used with a BS&B Burst Disk Monitor (Catalog 77-1009) or other suitable electrical equipment. The sensor is supplied with gaskets for installation between sanitary fittings on the downstream side of the rupture disk (bursting disc). Gasket materials available are Viton (white or black), EPDM (white or black) and silicone. Leaking disk detection is also available, contact BS&B for details.

The sensor is classified as a simple apparatus, and is suitable for use in hazardous locations provided it is used with other certified electrical apparatus (i.e. a Zener barrier) and properly installed and maintained. Maximum voltage 24Vdc. Maximum current 500mA.

Sanitary Clamps & Accessories

BS&B rupture disks (bursting discs) are installed between sanitary holder fittings and fixed in position using Tri-Clover clamp model 13 MHHS  (or equivalent) with hexagonal torque nut. A two-piece high pressure clamp model 13 MHP will be used with high burst pressure disks. Spool, tank or butt weld ferrule accessories are available.