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Seismic BreakAway Coupling from Metraflex

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The Metraflex Seismic BreakAway Coupling when your hangers are to short too allow full-rated movement

Designed to separate at a preset load greater than the seismic joint’s static weight, it gives your seismic joint complete freedom of movement during a seismic event.

How To Use The Metraflex Seismic BreakAway Coupling
The Seismic BreakAway Coupling separates at a preset load greater than the seismic joint’s static weight. This allows seismic joints to have complete freedom of movement so they can protect engineered piping systems and the building from damage during seismic events.

After a quake, the Seismic BreakAway Coupling can be reset, ready to protect piping during a future event.

Metraflex Seismic BreakAway Coupling Sizing Chart

Metraflex Seismic BreakAway Coupling Sizing Chart

Loop Size Loop Movement
+/-4″ +/-8″ +/-24″
0.5″

Coupling not needed for these sizes.

Metraloop is self supporting.

BAC65
0.75″ BAC65
1″ BAC65
1.25″ BAC65
1.5″ BAC65
2″ BAC80
2.5″ BAC80 BAC130
3″ BAC80 BAC80 BAC130
4″ BAC130 BAC130 BAC200
5″ BAC130 BAC130 BAC400
6″ BAC200 BAC200 BAC400
8″ BAC400 BAC650 BAC650

FAQ's

Metraflex Seismic BreakAway Coupling FAQ’s

Q: What is a Metraflex Seismic BreakAway Coupling?

A: The Metraflex Seismic BreakAway Coupling is an engineered release mechanism for the Fireloop®/seismic expansion joint. It releases the seismic joint to move through its full rated motion during a seismic event.

 

Q: How does it work?

A: The Metraflex Seismic BreakAway Coupling is designed to support the Fireloop® seismic expansion joint during its service life and “break-apart” at a preset load. The ball plunger design precisely sets the load for release and can be reset after activation. The preset load is typically 1.4-1.5 times the static weight of the Fireloop® seismic expansion joint. You can watch a video demonstrating the BreakAway Coupling.

 

Q: Is the Metraflex Seismic BreakAway Coupling UL or FM listed?

A: Both UL and FM have stated there is currently no test protocol for this innovative new product. Currently the Metraflex Seismic BreakAway Coupling falls under 2013 NFPA 13 section 1.7 “New Technology”. The Metraflex Seismic BreakAway Coupling supports the seismic joint and only releases during an earthquake.

Q: How is the Metraflex Seismic BreakAway Coupling different from a hanger?

A: A hanger is designed to support the dead weight of the water filled pipe. The Metraflex Seismic BreakAway Coupling is designed to support the Fireloop® seismic expansion joint and “release” during a seismic event, to allow the Fireloop® to move during an earthquake. After the event, the BreakAway Coupling can be reset and support the Fireloop® until the next seismic event.

Q: Have Metraflex’s installation instructions changed, replacing the threaded rod support with the Metraflex Seismic BreakAway Coupling?

A: Metraflex still recommends using the threaded rod as support where the installation has enough clearance for a minimum 12″ rod, which is the required length for +/- 4″ movement seismic joint. For Fireloop® seismic expansion joints with larger rated movements you are required to install a longer rod.

Q: What if I don’t have enough clearance for the length of threaded rod required to allow full-rated movement?

A: Use the Metraflex Seismic BreakAway Coupling. The Metraflex Seismic BreakAway Coupling has a very short dimension to allow for very tight installations. During a seismic event it will activate to allow the full-rated movement.

 

Q: Should I retrofit the Metraflex Seismic BreakAway Coupling where installations use a threaded rod for support?

A: We recommend retrofitting a Metraflex Seismic BreakAway Coupling only where the threaded rod is too short to allow full-rated movement of the seismic expansion joint.

Q: How much seismic joint movement is needed in order to consider using a Metraflex Seismic BreakAway Coupling?

A: Seismic joint installations should allow the joint to have its full-rated movement. The greater the rated movement, the longer the hangers and threaded rod need to be to get this amount of movement. The Metraflex Seismic BreakAway Coupling should be used when there is insufficient room for support(s) to be long enough and give the seismic joint its full-rated movement. The Metraflex Seismic BreakAway Coupling will allow an installation to achieve the full-rated movement even if hangers are too short. The Metraflex Seismic BreakAway Coupling eliminates the need for a long threaded rod.

 

Q: How do I prevent very long flexible legs from sagging?

A: Metraflex offers support saddles to keep the long, flexible legs of a seismic expansion joint from sagging, eliminating the need to design costly custom supports.

Q: How do I know which Metraflex Seismic BreakAway Coupling model I need?

A: Metraflex Seismic BreakAway Couplings are sized based on Metraflex Fireloop® seismic expansion joint sizes/weights. Simply tell us your Fireloop® joint’s size and movement and we’ll provide the correct Metraflex Seismic BreakAway Coupling. A sizing chart is also available, along with a video showing how the Metraflex Seismic BreakAway Coupling works. Metraflex Seismic BreakAway Couplings can be designed for Fireloop®seismic expansion joints with larger movements.

 

Q: How do I prevent a very large Fireloop® seismic expansion joint from moving too much when the Metraflex Seismic BreakAway Coupling is activated?

A: An optional cable tether is available which supports Fireloop® seismic expansion joint after the BreakAway Coupling has been activated. The cable tether allows full-rated movement while at the same time supporting the large seismic joint.

Accessories

Universal locking fitting; Additional support for big Metraloops

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