SEARCH · Search NASA
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
For reliability control of high pressure cryogenic systems, one or more 90 degree elbow expansion devices are substituted for the metal bellows normally used. The device consists of a conducting tube inside a support tube, with the space between the tubes evacuated for insulation.
A hand tool is designed for sealing metal fill tubes containing corrosive or inflammable liquids without the use of heat or open flame. The tool aligns the fill tube into which a tapered sealing pin is dropped and driven below the neck of tube.
Granular aluminum oxide is used as filler in serpentine tubing while welding the tubing to a flat surface. The filler eliminates obstructions in the tubes formed by molten weld nuggets and is porous enough to allow gases to escape from the welding area.
Sealed enclosure of heat-resistant glass tubing and silicone rubber molds provide good visibility for electron beam brazing of metal tubes in an inert gas atmosphere. The glass tubing and rubber molds, which are bonded together, are easily applied to and removed from the brazing area by operation of a clamp.
Teflon sleeve insert prevents contamination of internal tube surfaces by solder compound during soldering operations that connect and seal the tube ends. The sleeve insert is pressed into the mating tube ends with a slight interference fit.
Portable adapter assembly prevents damage to tubing and injury to personnel when pressurizing a system or during high pressure tests. The assembly is capable of withstanding high pressure. It is securely attached to the tubing stub end and may be removed without brazing, cutting or cleaning the tube.
Sealing hydraulic fluid within a tube and passing the tube through a reducing die produces high quality small diameter refractory metal tubing. The encased fluid eliminates the need for mandrel or ductile core removal and drawing can proceed with less handling operations.
Low-cost metal tube reducer accepts tubing up to 1 inch outer diameter and can reduce this diameter to less than 1/2 inch with controlled wall thickness. This device can reduce all of the tube without waste. It produces extremely good surface finishes.
Joint repair technique uses a longitudinally split aluminum shield over the joint ferrule and immediately adjacent tubing to reseal or reinforce leaking or weak joints in small tubing. Epoxy resin coating on inside surfaces of the two shield halves provides a tightly sealed bond between shield and tubing.
Report describes methods for the fabrication of tungsten and tungsten alloys into small-diameter, thin-wall tubing of nuclear quality. The tungsten, or tungsten alloy tube blanks are produced by double extrusion. Plug-drawing has emerged as an excellent secondary fabrication technique for the reduction of the overall tube dimensions.
Rectangular-bore tube improves population inversion obtained from upper and terminal laser states, resulting in a significant increase in unsaturated gain factor. Radial field produces efficient pumping of upper laser state. Narrow tube dimensions cause increased diffusion flow of neon is metastable states to tube walls.
Two versions of a portable tool repair the seats of tube fittings and the flared ends of tubing. Each version operates on the principle of lapping to remove imperfections from tube and fitting interfacing surfaces.
Portable electromagnetic coil enables high precision expansion or constriction and joining of large diameter metal tubes. A nonconducting mandrel or forming die is used on the side of the tubes wall opposite the coil. The coil is insulated from the tube by a thin plastic sleeve.
Metal tubes bonded together without heat application or brazing materials retain strength at elevated temperatures, and when subjected to constant or cyclic temperature gradients. Combination drawing and expansion process produces residual tangential tensile stress in the outer tube and tangential compressive stress in the inner tube.
Electrical data storage tube is assembled from standard vidicon tube using conventional amplification and control circuits. Vidicon storage tube is simple, inexpensive and has an erase and preparation time of less than 5 microseconds.
A compilation on the devices, techniques, and methods used in piping and tubing technology is presented. Data cover the following: (1) a number of fittings, couplings, and connectors that are useful in joining tubing and piping and various systems, (2) a family of devices used where flexibility and/or vibration damping are necessary, (3) a number of devices found useful in the regulation and control of fluid flow, and (4) shop hints to aid in maintenance and repair procedures such as cleaning, flaring, and swaging of tubes.
The development of a 25 watt high efficiency travelingwave tube at 8.5 GHz for space communications and telemetry applications is reported. Described is the design basis for the tube, which is known as the WJ-3703. Because of the combined high efficiency and high frequency requirements, the helix and body dimensions are very small and require special techniques for various assembly and construction procedures. These are described in detail. Measurement results of focusing tests and RF operation are given, but only pulsed RF performance of the tubes was obtained.
Description of proposed image tube optical systems for narrow-band direct photography and broad bandpass photography from spacecraft outside the atmosphere. For narrow-band photography an f/1.5 Schmidt camera with a photocathode located on the focal surface is recommended. The photoelectrons are accelerated and magnetically focused onto a phosphor/fiber optics surface, the curvature of which partially corrects for distortions of the electric field introduced by the curved photocathode. The second stage can be any other tube, electrostatically or magnetically focused, having a fiber optics faceplate butted to the first stage. For broad bandpass a spectrograph with an f/3 all-reflecting Schmidt image tube camera is recommended.