Dräger Ray

The Dräger Ray is a semi-closed circuit recreational diving rebreather designed to use standard nitrox breathing gas mixtures.

Construction

Harness and assembly

The soft harness has integrated over-the-shoulder counterlungs and buoyancy compensator bladder. The harness also carries a moderate sized scrubber canister on the upper back, and a single transversely mounted cylinder on the lower back. The Ray delivers a constant mass flow of gas to the breathing circuit through a Dräger Shark regulator and a metering orifice which is chosen from a small range, and which must be matched to the chosen gas mixture.

The whole unit excepting cylinders is supplied in a carrying case.

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  Harness, buoyancy compensator and counterlung assembly of a Draeger Ray SCR back view
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  Harness showing scrubber canister installed
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  Partly assembled Ray showing DSV connected to counterlungs. The scrubber is flipped up to show the hose routing
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  Draeger Ray SCR showing scrubber and ADV fitted and secured in place.
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  Draeger Ray SCR showing scrubber and ADV fitted and with cover in place - back view
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  Ballast weights for the Draeger Ray scrubber cover pockets
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  Draeger Ray SCR showing scrubber and ADV fitted and with cover in place - side view
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  Carrying case for Draeger Ray semi closed rebreather

Breathing loop

The standard unit provides a simple dive/surface valve (DSV) with mouthpiece, but an optional DSV connects to the Dräger Panorama full-face mask using the standard Dräger P-port connection system which is also used for the connections between the breathing hoses and counterlungs, and between the counterlungs and scrubber canister. The back mounted scrubber has axial flow, and has an auxiliary P-port on the base, which can be used to connect an optional oxygen monitor cell.

The automatic diluent valve is combined with the metering orifice as a single unit which plugs into a counterlung using a standard P-port connection.

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  Dive-surface valve and breathing hoses of a Draeger Ray
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  Dive-surface valve of a Ray - details
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  Scrubber canister of a Ray
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  Top end of Scrubber canister of a Ray
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  Components of Scrubber of a Ray
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  Interior of Scrubber canister of a Ray (without absorbent)
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  Constant mass flow orifice and automatic diluent valve from a Ray
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  Components of a constant mass flow orifice and automatic diluent valve from a Ray
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  Internal view of a constant mass flow orifice and automatic diluent valve from a Ray

Gas supply

The standard cylinder supplied with the unit is a 4-litre 200 bar steel cylinder, but it can also carry an 8-litre steel cylinder, which is about the same length but larger diameter. Standard open circuit bailout uses a Shark demand valve on the same first stage used for the metering and ADV. There is also a low pressure hose to supply the buoyancy compensator.

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  Regulator, bailout DV, CMF dosage and ADV, SPG and hoses from a Ray
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  Draeger Shark scuba demand valve used as bailout DV on a Ray
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  Draeger first stage regulator used on a Ray
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  Flow meter in box as supplied with Ray
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  Flowmeter as supplied with Ray
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  Flowmeter as supplied with Ray
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  Protective cover for Dräger cylinder valve for Nitrox

Operating principle

The Ray is a simple constant mass flow semi closed circuit rebreather.

References

Underwater breathing apparatus
Surface-supplied	Bailout bottle Diver's umbilical Diving air compressor Snuba Standard diving dress
Open-circuit scuba	Alternative air supply Aqua-lung Bailout bottle Diving regulator Porpoise regulator Purge button Scuba set
Rebreathers	Carleton CDBA CDLSE Cis-Lunar Cryogenic rebreather CUMA DSEA Dolphin FROGS Halcyon PVR-BASC IDA-71 Interspiro DCSC KISS LAR-5 LAR-6 LAR-V LARU Porpoise Ray Siebe Gorman CDBA Siva Viper
Helmets and masks	Diving helmet Full-face mask
Related	Booster pump Breathing gas Breathing performance of regulators Carbon dioxide scrubber Cascade filling system Diving air compressor Diving bell Diving cylinder Gas blending Gas blending for scuba diving Hydrostatic test Nitrox production membrane method pressure-swing adsorption Oxygen compatibility Sustained load cracking Testing and inspection of diving cylinders
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