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Ball, G. L., III

Publications and source records attributed to Ball, G. L., III.

Development of a polymetric grout for the hydrostatic bearing at DSS 14

Results of an investigation into the causes of the deterioration and premature failure of the grout under the hydrostatic bearing runner at DSS 14 are reported. Generic types of materials were screened and tested to find a grout material more resistive to the causes of grout failure. Emphasis was placed on the physical properties, strength, modulus of elasticity, and resistance to erosion and chemical attack by oil and unique requirements imposed by each material for mixing, placing, compacting, and cooling. The polymetric grout developed to replace the dry grout is described.

Mcclung, C. E.↗

Preparation, testing, and delivery of low density polyimide foam panels

Plastic foams based on polyimide resins were shown to be stable at relatively high temperatures, and to possess very low flame spread and smoke generation characteristics. A system and process were developed to prepare low-density polyimide foam from a liquid formulation. The system is based on the reaction of micropulverized grade pyromellitic dianhydride with a polymeric diisocyanate. The panels produced were postcured at elevated temperatures to achieve maximum thermal and fire resistance, and incorporation of a fire retardant into the formulation was considered. The effects of a flame retardant (Flameout 5600B1) were investigated, but eliminated in preference to the postcuring approach.

Ball, G. L., III↗

High temperature polyimide foams for shuttle upper surface thermal insulation

Polyimide foams developed by Monsanto Company were examined for use as upper surface space shuttle thermal insulation. It was found that postcured polyimide foams having a density of 64 kg/cu m (4 lb/cu ft) had acceptable physical properties up to and exceeding 700 K (800 F). Physical tests included cyclic heating and cooling in vacuum, weight and dimensional stability, mechanical strength and impact resistance, acoustic loading and thermal conductivity. Molding and newly developed postcuring procedures were defined.

Ball, G. L., III↗