Reverse Pressure Resistance
Product Model: ZD-RA01 (Standard Reverse-Acting)
Material: Disc: 316L Stainless Steel; Holder: Carbon Steel with corrosion-resistant coating.
Pressure Range: 1.0 barg to 16 barg.
Key Feature: Classic reverse-buckling design with integrated circumferential knife blades for clean shearing.
Operating Ratio: Up to 90% of minimum burst pressure.
Primary Use: General industrial protection for gas and vapor services where non-fragmenting operation is desired.
Overview
The standard reverse-acting rupture disc is a cornerstone of reliable, non-fragmenting overpressure protection. Its design, where the convex dome faces away from the pressure, provides inherent advantages in fatigue life and backpressure resistance. Upon reaching the set pressure, the disc instantaneously snaps inward (reverses) and is cleanly sheared by the sharp knife blades within the holder. This action guarantees a full, unobstructed opening while securely retaining the central disc portion, making it an ideal choice for protecting downstream equipment like compressors, blowers, or safety valves from damaging debris.
Features & Benefits
Non-Fragmenting Operation: The sheared disc center is captured, eliminating debris that could damage or clog sensitive downstream components.
Excellent Fatigue Resistance: Capable of withstanding a high number of pressure cycles, making it suitable for systems with frequent pressure fluctuations.
High Operating Pressure Ratio: Allows systems to operate safely at up to 90% of the disc's burst pressure, maximizing process efficiency.
Reliable and Proven Design: A widely adopted and trusted technology with a long history of reliable performance in diverse industries.
How It Works
Under normal pressure, the reverse dome is in compression. When the system pressure reaches the precise burst setting, the disc undergoes a rapid elastic instability, snapping inward. This reversal brings the disc into contact with a ring of sharp, precision-ground knife blades integrated into the holder, which shear the disc around its perimeter. The retained center piece ensures no fragments enter the downstream system.
Specifications (Descriptive)
Available in a wide range of sizes from DN25 to DN300. Common burst pressure settings for a DN80 model range from 3 to 10 barg. The knife blades are typically made from hardened 440C stainless steel for durability and a clean cut. Standard burst tolerance is ±5%. The disc is suitable for full vacuum service without additional supports. Standard temperature range for the 316L disc is -20°C to +400°C.
Q&A
Q: Why is this disc better for pressure cycling than a forward-acting type?
A: The reverse-acting disc is under compressive stress during normal operation, which is less likely to cause fatigue crack initiation compared to the tensile stress in a forward-acting disc. This gives it a significantly longer cycle life.
Q: Can it be used for liquid service?
A: It is not generally recommended. The buckling action requires a compressible fluid (gas/vapor) to initiate the reversal quickly and cleanly. For liquids, a forward-acting or specialty liquid-rated disc should be selected.
Q: What maintenance is required?
A: Very little. Periodic visual inspection of the external assembly is recommended. The internal mechanism requires no lubrication or adjustment. The disc should be replaced according to a time-based schedule or after any overpressure event.
About ZD Safety
Our standard reverse-acting discs are manufactured with precision and rigorously tested, embodying the reliable performance that industries have depended on for decades to protect critical assets without compromise.
