Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
PROPELLANT GRAIN GEOMETRY FOR CONTROLLING ULLAGE AND INCREASING FLAME PERMEABILITY
Document Type and Number:
WIPO Patent Application WO1997014169
Kind Code:
A3
Abstract:
A hollow grain propellant for use in a lightweight training round. The hollow grain propellant incorporates multi-perforation propellant grain geometry. The hollow grain propellant is configured as a propellant grain having a center hole surrounded by uniform perforations. The center hole is larger than any one of the uniform perforations. The placement of the uniform perforations forms webs of equal length. The hollow grain propellant may include seven or more perforations. The perforations are arranged in a single ring around the center hole. The size of the center hole may be controlled to produce a wide range of bulk densities. The number of perforations may be dependant on the size of the center hole. The number of perforations may be controlled to vary with the size of the center hole to provide for a desired bulk density. The large center hole improves flame permeability through a propellant bed by increasing the porosity of the propellent bed and increasing grain diameter. The hollow grain geometry maintains good progressive burning characteristics at low bulk densities while retaining low mass fraction at slivering. The hollow grain propellant further eliminates the need to reduce ullage with costly spacers, fillers, or liners.

Inventors:
LANGSJOEN PETER L
SPECK JAMES A
Application Number:
PCT/US1996/015615
Publication Date:
May 29, 1997
Filing Date:
September 27, 1996
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
ALLIANT TECHSYSTEMS INC (US)
International Classes:
C06B45/00; F42B5/16; (IPC1-7): H01J17/48; H02H1/00; H02H1/04; H02H3/22; H02H9/06
Foreign References:
US5251549A1993-10-12
US4846368A1989-07-11
US4627352A1986-12-09
US4386569A1983-06-07
US4094248A1978-06-13
US3931765A1976-01-13
US3429264A1969-02-25
US3418811A1968-12-31
US3105350A1963-10-01
US1077320A1913-11-04
US1074809A1913-10-07
Other References:
See also references of EP 0856194A4
Download PDF: