Co-Layered Propellant Manufacturing

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Co-Layered Propellant Manufacturing

• Richard S. Muscato
• Dr. Suzanne Prickett
• Christopher Gonzalez
• 29 October 2002

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Outline

• Description
• Milestones
• Capabilities
• Formulations
• Charge Design
• Benefits

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Co-layered Gun Propellant
Slower Burning Outer Layer
31 Ratio
Faster Burning Inner Layer

• Enhanced gun performance
• Increased charge weight
• Increased energy density
• Controlled pressurization

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Project Description

• Objectives
• Develop a process to manufacture co-layered
  propellant using two integrated twin screw
  extruders
• Product performance
• Affordable process
• Reproducible process
• Transition the technology to industry
• Approach
• Integrated Product/Process Development

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Project Milestones

• FY 02
• Co-extrusion capability established
• Co-extrusion feasibility for gun propellants
  validated
• Propellant formulations and charge design defined
• Continuous twin-screw processing of each
  individual formulation demonstrated
• FY 03
• Tooling design completed
• Tooling fabricated
• Post-extrusion process defined
• Initial process studies with co-extrusion system
  completed
• FY 04
• Process technology defined and demonstrated
• FY 05
• Optimized process technology transitioned to
  industry for production

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Previous Pilot Scale Capability

• WP ZSK-40 twin-screw extruder
• Process development facility (Class 1.1 700
  lbs)
• Processing rates
• 10 - 30 lb/hr (gun propellant)
• 25 - 50 lb/hr (extruded propellant)
• 25 - 100 lb/hr (cast composite propellant/PBX
  explosives)
• Six solid feeders (four feedstreams
  simultaneously)
• Four liquid pumps
• Limited automatic refill
• Product handling systems
• Extensive instrumentation/diagnostics

WP 40-mm extruder Building 1119
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New Co-extrusion Capability

• Objective Install a co-extrusion capability at
  IHDIV to process a co-layered gun propellant
  using two integrated twin screw extruders
• Construction complete Installed
• WP 37mm TSE with an upgraded Kubik hydrostatic
  drive
• Four temperature control units
• Zenith liquid feed system
• LIW vibratory tray solid feeder
• Remote vacuum pump system
• Material TPTs along the TSE barrel length
• Accelerometer devices for vibration monitoring
• Independent Allan Bradley PLC control system with
  DAS

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Facility Layout
Feeder Arrangement
Building Floor Plan
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Co-Extrusion Capability
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Co-Extrusion Die
Y
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Co-Extrusion Capability
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Co-Extrusion Capability
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Co-Extrusion Capability
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Propellant Formulations

• Investigated the effect of solid additives on
  EX-99 nitramine gun propellant
• Burning rate additives identified
• Batch mixes to downselect plasticizer
• Burning rates of final formulations required to
  finalize charge design

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Propellant Formulations
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Propellant Charge Design

• Cord
• Disks
• Concentric wrap

Propellant Wraps
5.2
Closure Plug
Igniter
5 Cartridge Case
5
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Project Benefits

• Capability Increase
• Gun Technology
• Improved performance
• Safety
• Reduction of material in process
• Enhanced personnel safety
• Environmental
• Reduction of waste propellant
• Minimization or elimination of solvents and
  associated wastes
• Reliability improvements
• Improved bond integrity
• Better dimensional control
• Improved product quality
• Labor
• Reduction in touch labor hours