Explosion relief vents are true blow –out type assemblies. Designed to NFPA-68 recommendations. These include a lightweight, (under 2.5 pounds per square foot). Panel, a reliable release system, and a means to restrain the panel after blowout.
The panel is a honeycomb core aluminum faced assembly with a perimeter seal track and a side mounted sponge seal. It weighs typically less than 2.0 pounds per square foot and is strong and impervious to vibration. It is designed to be reusable and does not degrade over time.
The release system consists of a number fracture releases or magnetic release mounted on arms that are re closable.
SM-M
Side Mount – Magnetic Release Relief Vent
Vents with magnetic releases (-M vents), used a rigid panel which responds to internal pressure. Two or more hinged magnetic releases hold the panel in place and sense the forces acting on it. An overpressure trips the releases and the vent swings open.
SM-DM
Side Mount – Direct Magnetic Release Relief Vent
The Model SM-DM Explosion Relief Vent is a rigid, light weight, insulated panel, hinged along its top edge and held closed by magnets along its lower edge. The panel is mounted in an angle frame.
Two magnets hold keepers attached to hinge extensions arms that span the panel. The panel is attached to the arms by posts and springs so that opening shock can be partially absorbed and distributed by a spring bed.
An internal pressure of 0.057 bar (585 mm, 23″, w.g.) opens the vent. The degree of rotation depends on the opening impulse and provision for limiting travel. On closing the magnets, rated at 75kg each, seize the keepers and the panel is re-closed without rebounding.
SM-T
Side Mount – Trigger Release Relief Vent
The trigger release is a strong mechanical latch of stainless steel that will open automatically at a set force. It extends the range of magnetic releases and is good in corrosive locations. Furthermore the trigger release will not permit vent opening below the set pressure and is the choice for vents operating under positive pressure.
As with our magnetic releases the trigger release is not torque sensitive and so the strike can vary in position on the fork jaw and, since rotation occurs after release, lubrication is never required. The release set point is set by the number and rating of the springs which are easily changed without tools or removal of the vent.
SM-F
Side Mount – Fracture Release Relief Vent
Type SM-F explosion relief vents are true blow-out type assemblies designed to NFPA-68 recommendations. These includes a lightweight, (under 2.5 pounds per square foot) panel, a reliable release system, and a means to restrain the panel after blowout.
The panel is a honeycomb core aluminum faced assembly with a perimeter seal track and side mounted sponge seal. It weighs typically less than 2.0 pounds per square foot and is strong and impervious to vibration. It is designed to be reusable and does not degrade over time.
The release system consists of a number of Fracture releases, as designed for the application, mounted on studs attached tot he housing around the spring form. For a certain percentage of their rating and deflection they act as a leaf spring clip holding the panel assembly tightly in place with good seal contact between the panel and housing. if there is an explosion the overload breaks the releases, instantly freeing the panel. Since there are no holes in the panel there is alignment problem. A change in the release rating is only a change of the Fracture Releases which are available over a wide range. The fixed rating and no moving parts avoids calibration and maintenance concerns. And if the panel is blown out only the releases need be replaced; a small fraction from the total assembly cost.
If the panel is blown out short cable tethers restrain it. These can be arranged to hinge the movement of the panel in the most advantageous direction for the application. A special modification uses four cables to make the panel blow straight out and deflect the blast sideways to help protect nearby passageways or equipment.
Any specific model of the type SM-F vent includes in its designation the vent opening size and the number of releases.
HM-M
Implosion – T-50 Release Relief Vent
The HM series of relief vents are designed for inward operation for application where excessive vacuum or implosion requires a fast acting relief device.
A lightweight honeycomb core panel is mounted within an angle iron frame. A seal on the panel lies flat against the frame and uses the vacuum pressure for sealing.
An external axle is mounted off the panel centerline and pivots on frame mounted ball bearings. Split journals make the panel easy to remove for access.
The off center axle position makes the panel a pressure sensor with a torque proportional to the vacuum. This torque is sensed by the Release.
RT-M
Roof Top Mount – Magnetic Release
Roof Top Vents The panel is a honey comb core aluminum faced assembly with a skirted top face and a flat sponge seal underneath. It is strong, weather tight, and does not degrade over time.
It is generally reusable if blown open it will be able to be latched again. Magnetic releases (-M vents), used a rigid panel which responds to internal pressure. Two or more hinged magnetic releases hold the panel in place and sense the forces acting on it. An over pressure trips the releases and the vent swings open.
RT-F
Roof Top Mount – Fracture Release
The panel is a honeycomb core aluminum faced assembly with a skirted top face and a flat sponge seal underneath. It is strong, watertight, and does not degrade over time. It is generally reusable if blown open as only the releases have to be replaced.
The design anticipates mounting on user supplied frames. These can be simple angle frames, with the vent mounted on the toe of one angle leg, or flat bar frames with angle clips for mounting the stud assemblies.
To mount a vent an angle frame is prepared to the inside dimensions shown and the weld nuts supplied are welded at the locations shown. It is held in place by the release clips which are tightened according to the instructions supplied.
The Fracture Releases are spring clips that break in the event of an explosion, freeing the panel. Cable tethers keep it from flying.
Since the panel has no holes and a smooth skirted aluminum top it has the ideal design for horizontal roof mounting. Where roof openings are large we always recommend flat bars on edge across the opening approximately 16″ apart to reduce the hazard of the large opening or high download.
RTR-F
Roof Top Round – Fracture Release
RTR-F vents are round shaped Type -F explosion relief vents are true blow-out type assemblies designed to NFPA-68 recommendations. These includes a lightweight, (under 2.5 pounds per square foot) panel, a reliable release system, and a means to restrain the panel after blowout.
The panel is a honeycomb core aluminum faced assembly with a perimeter seal track and side mounted sponge seal. It weighs typically less than 2.0 pounds per square foot and is strong and imperious to vibration. It is designed to be reusable and does not degrade over time.
The release system consists of a number of Fracture releases, as designed for the application, mounted on studs attached tot he housing around the spring form. For a certain percentage of their rating and deflection they act as a leaf spring clip holding the panel assembly tightly in place with good seal contact between the panel and housing. if there is an explosion the overload breaks the releases, instantly freeing the panel. Since there are no holes in the panel there is alignment problem. A change in the release rating is only a change of the Fracture Releases which are available over a wide range. The fixed rating and no moving parts avoids calibration and maintenance concerns. And if the panel is blown out only the releases need be replaced; a small fraction from the total assembly cost.
If the panel is blown out short cable tethers restrain it. These can be arranged to hinge the movement of the panel in the most advantageous direction for the application. A special modification uses four cables to make the panel blow straight out and deflect the blast sideways to help protect nearby passageways or equipment.
Any specific model of the type -F vent includes in its designation the vent opening size and the number of releases.
RTR-M
Roof Top Round – Magnetic Release
RTR-F vents are round shaped Vents with magnetic releases (-M vents), used a rigid panel which responds to internal pressure. Two or more hinged magnetic releases hold the panel in place and sense the forces acting on it. An overpressure trips the releases and the vent swings open.