Rupture Disks Combined with Safety Relief Valves

Product catalog summary

Overview: Pressure relief systems are essential in industrial settings to prevent overpressure situations. They typically employ pressure relief valves, rupture disks, or a combination of both to manage excessive pressure.

Key Components:

Rupture Disks: Non-reclosing devices that burst under pressure, ideal for systems with corrosive or hazardous substances due to their leak-tight seal.
Safety Relief Valves: Adjustable and reclosing valves that can be reused after pressure relief, though they may leak and require maintenance.
Combination Systems: Combining rupture disks and safety relief valves offers leak-tight protection, cost savings, and extended valve life by isolating the valve from process media.

Advantages of Rupture Disk/Valve Combinations:

Zero process leakage to the atmosphere.
Extended intervals between major overhauls due to reduced process contamination.
Cost savings from using less expensive valve materials.
Extended valve life by preventing product buildup on valve components.
In-place testing of safety relief valves is possible.

ASME Code Compliance: The document details the ASME Pressure Vessel Code, Section VIII, Division 1, requirements for pressure relief devices, including design, testing, and marking for rupture disks and safety relief valves.

Product Recommendations: BS&B recommends the Sta-Saf® lineup of reverse buckling rupture disk devices for isolating safety relief valves, designed for non-fragmentation and ultimate leak-tightness across various pressures and applications.

Installation and Testing: Guidelines are provided for selecting and installing rupture disks in new constructions and retrofits, along with methods for testing the set pressure of safety relief valves in place.

Conclusion: Combining rupture disks and safety relief valves provides a robust solution for pressure relief in industrial systems, ensuring safety, compliance, and cost-effectiveness.

Specifications and Procedures:
1. A capacity factor must derate the ASME rated relieving capacity of safety relief valves, with a default factor of 0.90 if not tested.
2. Rupture disk/relief valve combinations not flow tested must be derated to 90% of the valve's rated capacity.
3. An additional nameplate is required for rupture disk devices used with relief valves, detailing valve type, disk holder type, disk type, and flow capacity.

Installation Guidelines:
1. Rupture disk devices may be installed on the outlet side of a pressure relief valve under specific conditions to prevent pressure accumulation and ensure proper valve operation.
2. The pressure relief valve must meet capacity requirements, and the rupture disk's burst pressure must not exceed design limits.
3. The system must handle leakage effects and ensure reliability.

Combination Capacity and Testing:
1. Rupture disk devices can be installed between a pressure relief valve and the vessel, with specific capacity requirements.
2. The combination capacity must be established according to UG-132, and the space between the disk and valve must have a pressure indicator.
3. The rupture disk opening must allow flow equal to the valve's capacity without interference.

Footnotes and Warnings:
1. The use of rupture disk devices with pressure relief valves must be evaluated to ensure proper operation.
2. Users are warned about potential issues with pressure buildup and leakage affecting valve operation.

Contact Information:
BS&B Safety Systems provides contact details for various global locations, including the USA, Canada, Brazil, Mexico, Ireland, UK, Germany, UAE, Russia, China, India, Singapore, and Japan.

Catalog excerpts

Rupture Disks Combined with Safety Relief Valves-1

Rupture Disks Combined with Safety Relief Valves Visit www.bsbsystems.com or www.bsb.ie for the most complete, up-to-date information

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Rupture Disks Combined with Safety Relief Valves-2

Instructions The ASME Pressure Vessel Code permits the use of a rupture disk device at both a safety relief valve inlet and outlet. This combination, once considered a luxury, has proven itself to save money through: • Zero process leakage to the atmosphere • Longer periods between major overhauls • Valves can be tested in place • Less expensive trim material can be used •Valve life is extended by isolating internal valve parts from corrosive units This bulletin has been published to give you the facts, the advantages, applications and applicable portions of the ASME Code which governs this topic....

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Rupture Disks Combined with Safety Relief Valves-3

Safety Relief Valve Isolation BS&B recommends the Sta-Saf® lineup of reverse buckling rupture disk devices when isolating safety relief valves. Sta-Saf products cover most ranges of safety relief valve pressures ranging from 5 psig (0.34 barg) to over 3000 psig (208 barg). Safety Relief Valve Sta-Saf disks offer the user a vacuum resistant, solid metal rupture disk designed for non-fragmentation and ultimate leak-tightness. Each Sta-Saf Rupture disk is available in a pre-torqued SRB-7RS Safety Head that allows the rupture disk to be removed from service, then inspected, cleaned and reinstalled...

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Rupture Disks Combined with Safety Relief Valves-4

Figure 3b Type AV Disk fits between standard flanges 2. RETROFIT - INLET TO VALVE For isolating safety relief valves already in service with rigid discharge piping, the SVI rupture disk assembly is recommended (figure 3a). The SVI is a reverse buckling rupture disk welded into a one piece metal assembly. Supplied with affixed gasket for immediate assembly. The SVI easily slips into the inlet piping. Advantages include: • No safety head required Figure 3a SVI Disk installs • Fits into inlet piping easily into inlet • Non-fragmentation piping • Available in sizes 1.5” (40mm) and larger Facts in...

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Rupture Disks Combined with Safety Relief Valves-5

ASME PRESSURE VESSEL CODE, SECTION VIII, DIVISION 1, 2010 EDITION Rupture Disks and Safety Relief Valves Defined UG-126 UG-127 P R E S S U R E R E L I E F NONRECLOSING PRESSURE RELIEF DEVICES VALVES45 (Meeting the Requirements of ASME CODE, 2010 Section VIII Division 1) (a) Safety, safety relief, and relief valves shall be of the direct spring loaded type. (b) Pilot operated pressure relief valves may be used, provided that the pilot is self-actuated and the main valve will open automatically at not over the set pressure and will discharge its full rated capacity if some essential part of the...

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Rupture Disks Combined with Safety Relief Valves-6

MEETING ASME CODE Capacity of Combination In order to meet the ASME code, the Safety Relief Valve capacity of the combination of the safety relief valve and rupture disk must be determined one of two ways: A) Flow test the combination to arrive at a “certified combination capacity factor”. Testing must be done in accordance with Paragraph UG-132 and approved by the National Board of Boiler and Pressure Vessel Inspectors. Excess Flow Valve Rupture Disk Rupture disk/relief valve combiSafety Head nations with flow tests will be Flange allowed a relieving capacity of the valve multiplied by a correction...

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The Application of Rupture Disk Installed Between Pressure Relief Valves UG-127 (b) A rupture disk device may be installed between a pressure relief valve52 and the vessel provided: (1) The combination of the pressure relief valve and the rupture disk device is ample in capacity to meet the requirements of UG133(a) and (b); (2) the marked capacity of a pressure relief valve (nozzle type) when installed with a rupture disk device between the inlet of the valve and the vessel shall be multiplied by a factor of 0.90 of the rated relieving capacity of the valve alone, or alternatively, the capacity...

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BSBSystems.com Visit our website for the most complete, up-to-date information Limerick, Ireland T +353 61 484700 F +353 61 227987 E [email protected] United Arab Emirates T +971 2406 9603 F +971 2406 9810 E [email protected] Products, specifications and all data in this literature are subject to change without notice. Questions regarding product selection and specifications for specific applications should be directed to BS&B Safety Systems, L.L.C. or BS&B Safety Systems Ltd. All sales are subject to BS&B Safety Systems, L.L.C. or BS&B Safety Systems Ltd. standard terms and conditions of sale....

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