Shand & Jurs 94510 MagnaVent Emergency Vent

For tank-safety engineers, refinery specifiers, and emissions-program managers, the Shand & Jurs 94510 MagnaVent is a magnetic-latch emergency vent that delivers instantaneous, full-lift pressure relief for atmospheric storage tanks under fire-case and abnormal overpressure events.

Unlike weight-loaded or spring-loaded emergency vents that simmer as pressure approaches setpoint and lift progressively, the MagnaVent holds the pallet firmly sealed by a rare-earth magnetic latch and releases in a single snap-action when the calibrated threshold is reached — no creep, no premature venting.

The magnetic release threshold does not drift over years of service, so field recalibration is not required. Proprietary Expanda-Seal technology creates a pressure-energized seat seal that tightens with rising tank pressure, delivering measurable fugitive-emissions control up to setpoint.

Available 4, 6, 8, and 10 inches with ANSI 150 or manway mounting, ATEX certification, and WinSize software sizing support. Set-pressure range is 0.5 to 2.75 PSIG.

Features

Holds the pallet firmly sealed as tank pressure rises, then releases in a single snap-action at the calibrated threshold without simmering or premature venting.

Magnetic release does not drift over years of service, unlike spring or weight mechanisms whose setpoints shift with wear, eliminating field recalibration.

Pressure-energized seat seal tightens with rising tank pressure, delivering measurable fugitive-emissions control up to setpoint during normal operation.

Single snap-action opening delivers full relief capacity the moment setpoint is crossed, supporting fire-case sizing without the partial-lift losses of direct-acting vents.

Combines emergency venting capability with tank-roof manway access in a single assembly, reducing nozzle count on atmospheric storage tank installations.

ATEX certification supports installation in classified European explosive atmospheres; ANSI, EN1092-1, and JIS flange drillings fit global tank standards.

Applications

Fire Case Relief: Delivers rapid full-lift emergency discharge sized per API 2000 fire-case methodology, protecting tanks during external fire exposure or rapid vapor generation.
Atmospheric Storage Tanks: Provides secondary overpressure protection independent of conservation vent performance, safeguarding tank integrity during abnormal internal pressure excursions.
Petroleum Terminals: Protects crude, product, and intermediate tanks where simmering or drifting setpoints on conventional emergency vents would carry emissions and compliance risk.
Chemical Storage: Aluminum, carbon steel, or stainless steel body with FEP, FKM, NBR, or PFA seal materials extends compatibility across hydrocarbon and industrial vapor services.
External Heat Exposure: Magnetic latch delivers instantaneous release at calibrated threshold during external fire or process heat events, limiting structural stress on tank shells and roofs.
API 2000 Architecture: Designed around API 2000 emergency-venting sizing, with WinSize software support for documented capacity selection and defensible engineering review.

Specifications

Parameter

Specification

Device Type

Emergency pressure relief vent

Operating Principle

Magnetic latch pressure release

Set Pressure Range

0.5 – 2.75 PSIG

Sealing Method

Magnetic latch with Expanda-Seal diaphragm

Opening Mechanism

Magnetic-latch hinged cover

Nominal Sizes

4″, 6″, 8″, 10″

Connection Types

ANSI 125/150 FF; EN1092-1 PN16; JIS 10K

Body Materials

Aluminum, Carbon Steel, or Stainless Steel

Body and Seat

304 or 316 Stainless Steel

Pallet / Cover Materials

Aluminum or Stainless Steel

Seal Materials

FEP, FKM, NBR, or PFA

Magnet Type

Permanent magnet (rare-earth)

Temperature Range

−40°F to +140°F (−40°C to +60°C)

Certifications

ATEX; CE

Sizing Support

Shand & Jurs WinSize software; designed around API 2000 emergency-venting architecture

Options

Aluminum / carbon steel / stainless steel body, ANSI or EN1092-1 flange drilling, ATEX hazardous-area certification, FEP / FKM / NBR / PFA seal materials, security seal accessory

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Contact Support

If you have questions not covered here, please contact the Cognesense support team for assistance.

Why use a magnetic-latch vent instead of a weight-loaded or spring-loaded emergency vent?

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Weight-loaded and spring-loaded emergency vents begin to simmer as tank pressure approaches setpoint — the cover lifts partially, leakage rises, and full relief is not achieved until well above setpoint. The MagnaVent uses a rare-earth magnetic latch that holds the cover firmly sealed until the calibrated threshold, then releases in a single snap-action. There is no simmering, no creep, and no partial lift.

Does the magnetic setpoint drift over time?

No. Unlike spring or weight mechanisms, whose setpoint changes as the spring or seat wears, the magnetic release threshold does not drift over years of service. Field recalibration is not required on the MagnaVent.

Is the 94510 a primary or secondary device?

The 94510 is an emergency vent — secondary protection. It operates independently from the tank’s conservation vent, providing high-volume discharge during abnormal overpressure events such as external fire, rapid vapor generation, or loss of the primary vent. Routine breathing is handled by a separate conservation vent.

What sizes and flange options are available?

The MagnaVent is available in 4″, 6″, 8″, and 10″ nominal sizes with ANSI 125/150 FF, EN1092-1 PN16, and JIS 10K flange drillings. Manway-mounted configurations combine emergency venting with tank-roof access.

What approvals are available?

ATEX certification is available and CE certification applies. ANSI, EN1092-1, and JIS flange drillings support global installation. Final site-specific conformance to regulatory or insurance programs (e.g., API 2000, fire-code review) is determined by the owner / operator through engineering review.

How is the 94510 sized?

Emergency relief capacity is sized around API 2000 emergency-venting architecture. Shand & Jurs WinSize software produces size, set-pressure, and configuration documentation suitable for engineering and regulatory review.

What is the temperature range?

The MagnaVent is rated for −40°F to +140°F (−40°C to +60°C) service. For installations outside this window, consult Cognesense applications support to confirm material and magnet selection.

Summary

With over a century of tank-safety heritage inside Cognesense, the Shand & Jurs 94510 MagnaVent emergency vent protects atmospheric storage tanks against fire-case and abnormal overpressure events with a rare-earth magnetic latch that delivers instantaneous, full-lift relief. The non-drifting magnetic threshold, Expanda-Seal seat, and snap-action release eliminate the simmering, creep, and recalibration typical of spring- or weight-loaded designs. With ATEX certification, ANSI and EN1092-1 flange options, and WinSize sizing support, the MagnaVent helps terminals and chemical sites measure, monitor, and protect what matters most.

94510 MagnaVent Emergency Vent