A Marman clamp is a type of heavy-duty band clamp; it allows two cylindrical objects to be clamped together end-to-end with a ring clamp. It is sometimes also known as a "Marman ring". It consists of a circular strap with an interior V-shaped groove. Tension is applied to the strap with a threaded bolt and nuts connecting to the ends of the strap. As the tension increases, the V-groove wedges over flanges on the circular parts to be assembled, providing the force that holds the ends of the two cylinders together. The Marman clamp is an alternative to a bolted flange connection which would be heavier and require more labor to connect. Another variety uses a flat strap, used where systems carry low pressure or to hold a cylindrical object in position.

Hose connectors

A common use for Marman clamps is as quick-disconnect connectors in flexible aircraft fuel lines.

Spacecraft separation

Marman clamps are used extensively in spaceflight systems and are common mechanical load-transfer and clamping mechanisms for connecting the

upper stage A multistage rocket or step rocket is a launch vehicle that uses two or more rocket ''stages'', each of which contains its own engines and propellant. A ''tandem'' or ''serial'' stage is mounted on top of another stage; a ''parallel'' stage is ...

and the

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioiso ...

payload Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...

space Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually consi ...

vehicles A vehicle (from la, vehiculum) is a machine that transports people or cargo. Vehicles include wagons, bicycles, motor vehicles (motorcycles, cars, trucks, buses, mobility scooters for disabled people), railed vehicles (trains, trams), ...

, for example, on the Cassini Plasma Spectrometer on the

Cassini orbiter Cassini may refer to: People * Cassini (surname) * Oleg Cassini (1913-2006), American fashion designer :Cassini family: * Giovanni Domenico Cassini (1625–1712), Italian mathematician, astronomer, engineer, and astrologer * Jacques Cassini (1 ...

. They may also be used to join stages of a booster rocket. Early separation systems using Marman clamps used

explosive bolt A pyrotechnic fastener (also called an explosive bolt, or pyro, within context) is a fastener, usually a nut or bolt, that incorporates a pyrotechnic charge that can be initiated remotely. One or more explosive charges embedded within the bolt a ...

s for release. These have problems of unpredictability, the need to contain debris and difficulties in testing them. A more recent approach uses a screw thread. The tension of the clamp band itself is used to power the unscrewing of a central bolt, when released by a NASA Standard Initiator (NSI), a pyrotechnic pin puller.

History

The Marman clamp was first produced by Herbert Marx, better known by his stage name

Zeppo Marx Herbert Manfred "Zeppo" Marx (February 25, 1901 – November 30, 1979) was an American comedic actor, theatrical agent, and engineer. He was the youngest and last survivor of the five Marx Brothers. He appeared in the first five Marx Brothers f ...

; it was manufactured by his company, Marman Products from the 1930s. At the time it was designed to secure cargo during transport. The U.S. Military used Marman clamps to transport the

atomic bomb A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or a combination of fission and fusion reactions ( thermonuclear bomb), producing a nuclear explosion. Both bomb ...

s used at the end of the Second World War. Marman clamps are found in many modern moving vehicles, though the screw band type clamp is becoming more popular.

References

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External links

The CAPS Launch Latch
Clamps (tool) Plumbing Spaceflight technology

Hose connectors

Spacecraft separation

History

See also

References

External links