Flat Composite Disc

Flat Composite Disc

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Forward acting rupture disc, Flat Composite for very low pressure applications

Economic solution for very low pressure applications

Flat Composite is a tension-loaded forward acting rupture disc of composite design with a unique tri-membrane construction. The Flat Composite (FCD) rupture disc offers the widest size range of any product type and acts as a reliable solution across a wide variety of process conditions especially where there is a requirement for very low burst pressures.

Widest size range for low pressures

The Flat composite design has the widest size range of any product type Elfab offer, ranging from 25mm to 800mm. Its tri-membrane construction comprises a sealing membrane with a choice of metals ranging from Stainless Steel as standard to hastelloy, Nickel, Inconel or Monel to best suit the process conditions. The Flat Composite is designed for use with Elfab’s standard forward acting rupture disc holder, also available in a wide range of corrosive resistant materials. Further benefiting from a +/- 5% tolerance with a wide temperature compatibility, Flat Composites are a cost effective solution for many process conditions.

Non-fragmenting composite disc design

This non-fragmenting rupture disc design, provides enriched protection, reliability and accurate burst control to various applications. The Flat Composite is manufactured with various slotting arrangements to meet customers’ specific application requirements. Compatible with liquid, gas or vapour mediums the Flat Composite can withstand vacuum or back pressures when fitted with a vacuum support making this composite design suitable for a range of process conditions.







Cutting costs on rewiring

Flat Composite is fitted with Flo-Tel actuator as standard, and installed into Elfab’s forward-acting rupture disc holder. The flat bursting disc design is used for achieving very low burst pressures, and with Elfab’s unique, reusable, non-invasive burst detection system Flo-Tel™+, the customer will benefit from reliable burst detection in environments where other detectors may not accurately function as well as significant cost savings.

Leading the industry in advanced quality performance

Elfab pride themselves in offering the highest level of quality and are accredited to a number of leading industry standards. Elfab’s rupture discs can be manufactured to ISO 4126 or ASME VIII dependent on customers’ requirements.

When used in combination Elfab’s rupture discs and detection systems can offer industry leading SIL ratings to offer customers increased safety information. Please contact our technically trained sales engineers for more information.

• Up to 40% operating ratio
• Widest size range of any product type
• Manufactured to ISO4126 or ASME VIII (UD stamp available)
• Available in a wide range of materials
• Non-fragmenting bursting disc design
• Full vacuum capability when manufactured with opening or non-opening vacuum support
• Suitable for liquid, gas and vapour applications
• Compatible with reusable detection systems Flo-Tel™ and Flo-Tel™ xd




Contact Elfab about this product
Size Range 25mm to 800mm (1” to 32”)
Burst Pressure Range 0.07 barg to 3.5 barg (1 Psig to 50 Psig)
Temperature Range See product downloads
Maximum Operating Ratio 40% of minimum burst pressure (36% of nominal burst pressure)
Fragmentation on Burst Non-fragmenting design
Relief Valve Isolation Suitable
Vacuum Service Back pressure support required
Fluid Compatibility Liquid, Gas or Vapour
KR Values 3.94
Torque Sensitive No
Cycle Life Poor
Material Range Stainless Steel as Standard. Others Available
Reversal Ratio <1 (Fail Safe) Dependent on Back Pressure Support
Damage Ratio <1 (Fail Safe)
Leak Tightness Good
Performance Tolerance +/- 5% (zero manufacturing design range)
Protective Linings Not Available
Disc Surface Finish N/A