Cold Gas Thruster

Cold Gas Thruster

ESA - SWARM.

This spacecraft thruster has been developed for cold gas propulsion applications requiring a thrust between 10 mN and 100 mN.

Based on the Nammo Space well-established SVS01 range of high performance solenoid valves; the SVT01 series of Cold Gas Thrusters has been in production for over fifteen years.  Across the range, the same solenoid body is used, with the variation in thrust being achieved with an interchangeable nozzle cone at the outlet. This system allows the incorporation of a baffle which protects the elastomeric seal from atomic oxygen attack.

The mono-stable solenoid uses a single coil to energise the movement of a suspended sealing armature.  This assembly is located using a diaphragm spring to eliminate sliding fit issues.  The armature to seat profiles have been designed to minimise flow discontinuities, thereby reducing the susceptibility to contamination induced failures. It also uses a flat faced seal to reduce the risk associated with valve internal leakage due to a high cycle life.

When in the unpowered state, system pressure forces and a spring, work together to keep the armature held in the closed position.  The coil resistance, inlet filter rating, seal material and mechanical interfaces are all adjustable to suit the customer requirements.

Performance Characteristics

Operating Media

GN2, CF4, GXe

Maximum Operating Pressure

Proof Pressure

Operational Temperature

Vacuum Thrust

Specific Impulse, GN2

72 seconds [nominal]

Specific Impulse, CF4

47 seconds [nominal]

Specific Impulse, GXe

30 seconds [nominal]

Thrust Vector Accuracy

<1°

Impulse Bit Repeatability

<5%

Electrical Interface

Flying leads

Coil Resistance

Response Time

Power Consumption

Internal Leakage

1 x 10-4 scc/s GHe max at 1.5 bar

External Leakage

Operating Cycle Life

1,500,000 cycles

Filter Rating

25 µm absolute

Construction Materials

AISI304L, Radiometal 4550, Silicone/EPDM Rubber

Hardware Mass

60 gram

Envelope

24 x 24 mm flange, 16 mm cylinder OD, 52 mm length

Fluidic Interface

Structural Interface

Mounting

Technology Readiness Level

Flight Qualified, TRL9

Status

The thruster has flown on a variety of spacecraft, including:

 

NAMMO CHELTENHAM

GENERAL CAPABILITIES

  • Dedicated, skilled space engineering team
  • Experienced Assembly Integration and Test team
  • Program Management

QUALITY AND INSPECTION

  • Certified to AS9100
  • Inspection department including CMM and optical measuring equipment
  • Laser part marking
  • Complete traceability of inspection records
  • Material traceability from original mill source to final components

CLEANROOM and ENVIRONMENTAL TESTING

  • ISO Class 8 environment, with Class 5 laminar flow booths
  • Large 1m diameter x 2m long Vacuum chamber
  • Thermal vacuum chambers
  • Thrust test facility
  • Vacuum/leak testing and pressure testing.
  • Air borne and liquid Particle measurement.
  • Pressure test facility to 1500 bar
  • Computer controlled TIG and Orbital TIG weld facility

Contact

Nigel Kay

General Manager

Post
36 Central Way, Cheltenham Trade Park, Cheltenham, GL51 8LZ, UK

Phone
+44 7714 322866

Location

Nammo Cheltenham

Address
Nammo Cheltenham,
Enterprise Way,
Cheltenham, UK