Engineering topics
Publications and source records attributed to Welch, Peter J..
Improved bubble-point test devised for large pleated filter elements. Sizes of pores in filters determined more accurately. Test method replaces older test accurate for pore sizes of 20 microns or less, but subject to gross inaccuracy for filter elements with pores of 70 microns or larger. Unlike older test, no measurement of pressure is necessary. Also no need to estimate average depth of filter-element pleats below surface of liquid.
The current status of the evaluation program is presented. The objective was to evaluate the applicability of Thermal Sprayed Coatings (TSC) to protect the structures in the high temperature acid environment produced by exhaust of the Solid Rocket Boosters during the launches of the Shuttle Transportation System. Only the relatively low cost aluminum TSC which provides some cathodic protection for steel appears to be a practical candidate for further investigation.
Commercially available composite structural shapes were evaluated for use. These composites, fiberglass-reinforced polyester and vinylester resin materials are being used extensively in the fabrication and construction of low maintenance, corrosion resistant structures. The evaluation found that in many applications these composite materials can be successfully used at the space center. These composite materials should not be used where they will be exposed to the hot exhaust plume/cloud of the launch vehicle during the liftoff, and caution should be taken in their use in areas where electrostatic discharge and hypergolic propellant compatibility are primary concerns.