Rockets motor

In addition to catalysts, stabilizers, opacifiers (to reduce heat radiation ahead of the flame), flash depressants, plasticizers, and binders, the main fuel and oxidizers for rocket propellants include 

While the term missile can apply to any projectile ammunition, guided missiles describes those rockets whose course or trajectory is controlled electronically by computers and communications equipment. 

Torpedoes are tubular rockets or missiles designed to operate underwater. They are the principal weapons of submarines but may be dropped from aircraft or surface vessels. Torpedoes may be expelled by compressed air or propelled by a propelling charge, steam, or electricity. 

Warheads contain the agent intended to inflict damage in any projectile ammunition, be it inert, explosive, nuclear, biological, or chemical, although the term is most often applied to self-propelled missiles, rockets, and torpedoes. Warheads include casings, destructive agents, and a power supply. They may be loaded into the ammunition just before use. With the addition of fuzes, safety, and arming mechanisms, warheads become armament systems. 

Many types of ammunition are not projected toward their target and, therefore, do not contain a propelling or expelling charge. They do, however. 

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Another application of laser-based profilometry is the inspection of rocket and missile components. The U.S. Air Force has funded work to develop a non-contact laser-based profilometer for the inside surface of solid rocket motors. Over time, these devices are subject to slumping and cracking, which could potentially render the rocket motor ineffective and hazardous. When fully implemented, this system will provide a meaningful screening method for evaluating the condition of aging rocket motors. 

Rocket propellants must not contain sizable cracks, pores, or cavities. They are inspected using x-rays and ultrasonics, and firings are conducted in strand burners, intermpted burners, and in reduced or full-scale rocket motors (see also Nondestructive evaluation) (16—20). 

Pollution Prevention. Procedures haven been developed for recovery of composite ammonium perchlorate propellant from rocket motors, and the treatment of scrap and recovered propellant to reclaim ingredients. These include the use of high pressure water jets or compounds such as ammonia, which form fluids under pressure at elevated temperature, to remove the propellant from the motor, extraction of the ammonium perchlorate with solvents such as water or ammonia as a critical fluid, recrystalli2ation of the perchlorate and reuse in composite propellant or in slurry explosives or conversion to perchloric acid (166,167). 

J. W. Cole, "Non-Destmctive Testing of Large Rocket Motors A State of the Art Survey," in Bulletin of the Joint Meeting—JANNAF Panel of Physical... 

S olid Propellant ProcessingFactors in Rocket Motor Design, Space Vehicle Design Ciiteiia Monograph, SP-8075, NASA, Airport, Md., 1971. 

T. D. Wilson and O. T. Moskios, Disposal of Solid Rocket Motor Propellants, CPTR89-45, CPIA Pubhcations, Johns Hopkins Urdveisity, Lauiel, Md., July 1989. 

Monographs on rockets and rocket propellants by the National Aeronautics and Space Administration (NASA), Lewis Research Center, Cleveland. These iaclude the foUowiag Solid Propellant Selection and Characteri tion, Report SP-8064,1971 Solid Rocket Motor Peformance, Report SP-8039,1971 Solid Rocket Motor Igniters, Report SP-8051,1971 Solid Rocket Motor Metal Cases, Report SP-8025, 1970, and Captive Eire Testing of Solid Rocket Motors, Report SP-8041,1971. 

The U.S. domestic capacity of ammonium perchlorate is roughly estimated at 31,250 t/yr. The actual production varies, based on the requirements for soHd propellants. The 1994 production ran at about 11,200 t/yr, 36% of name plate capacity. Environmental effects of the decomposition products, which result from using soHd rocket motors based on ammonium perchlorate-containing propellants, are expected to keep increasing pubHc pressure until consumption is reduced and alternatives are developed. The 1995 price of ammonium perchlorate is in the range of 1.05/kg. Approximately 450 t/yr of NH ClO -equivalent cell Hquor is sold to produce magnesium and lithium perchlorate for use in the production of batteries (113). Total U.S. domestic sales and exports for sodium perchlorate are about 900 t/yr. In 1995, a solution containing 64% NaClO was priced at ca 1.00/kg dry product was also available at 1.21/kg. 

A steady-state rocket-type combustion spray unit has been developed, called high velocity oxy fuel (HVOF), that creates a steady state, continuous, supersonic spray stream (1.2—3 mm dia) resembling a rocket motor exhaust. The portable device injects and accelerates the particles inside a barrel (rocket nozzle). It produces coating quaHty and particle velocities equal to the D-gun at 5—10 times the spray rate with significantly reduced coating costs. 

Products can be found in every principal market area including rocket motor and shell casings, air and gas pressure tanks, aircraft wing fuel tanks, utihty poles, automotive and tmck drive shafts, sailboat masts, vaulting poles, fishing rods, golf shafts, railroad tanks cars, and pipes and tanks for oil, gas, and chemical processing. 

Parts with fiber volume fractions up to 60% can be fabricated by filament winding. The procedure is often used to manufacture composite rocket motors, corrosion-resistant tanks and storage containers, and piping for below-ground appHcations. 

An important appHcation is for filament-wound glass-reinforced pipe used in oil fields, chemical plants, water distribution, and as electrical conduits. Low viscosity Hquid systems having good mechanical properties (elongation at break) when cured are preferred. These are usually cured with Hquid anhydride or aromatic-amine hardeners. Similar systems are used for filament-win ding pressure botdes and rocket motor casings. 

Originally developed for tyre cords, Kevlar-type materials have also become widely used in composites. Uses include filament-wound rocket motors and pressure vessels, metal-lined Kevlar-overwrapped vessels in the space shuttle, boat and kayak hulls, Kevlar-epoxy helmets for the US military, and as one of the reinforcements in composite lorry cabs. 

The cycloaliphatic resins also are clearly superior in arc resistance and arc track resistance. This has led to applications in the tension insulators, rocket motor cases and transformer encapsulation. 

Epoxide resin laminates are of particular importance in the aircraft industry. It has been stated that the Boeing 757 and 767 aircraft use 1800 kg of carbon fibre/ epoxide resin composites for structural purposes per aeroplane. The resin has also been used with Aramid fibres for filament-wound rocket motors and pressure vessels. The AV-18 fighter aircraft is also said to be 18% epoxide resin/cc bon fibre composite. The resins are also widely used both with fibres and with honeycomb structures for such parts as helicopter blades. 

In contrast, there is also current interest in investigating PAN-based fibers in low thermal conductivity composites [62], Such fibers are carbonized at low temperature and offer a substitute to rayon-based carbon fibers in composites designed for solid rocket motor nozzles and exit cones. 

Phenolic resins are adaptable to many applieations. The list is very long, however, the major uses are wood binders, glass insulation binders, molding compounds, laminates, foundry binders, coatings, friction linings, abrasives, and oil well propants [59-66]. They have found their way into a number of new, high technology uses such as rocket motor wear parts, military armor, sports equipment. 

There now exist alternatives or sufficient quantities of controlled substances for almost all applications of ozone-depleting solvents. Exceptions have been noted for certain laboratory and analytical uses and for manufacture of space shuttle rocket motors. HCFCs have not been adopted on a large scale as alternatives to CFC solvents. In the near term, however, they may be needed as the conventional substances in some limited and unique applications. HCFC-141b is not a good replacement for methyl chloroform (1,1,1 -trichloroethane) because its ODP is three times higher. Alternatives for specific uses of ozone-depleting solvents are briefly described below. 

Figure 1-11 Filament Winding a Rocket Motor Case...

Interest in the production of high-energy oxidizers for use in rocket motors has stimulated the study of peroxo compounds bound to highly electronegative groups during the past few decades. Although such applications have not yet materialized, numerous new compounds of this type... 

At one time this latter reaction was used in experimental rocket motors, the CIF3 oxidizer reacting spontaneously with the fuel (N2H4 or Me2N2H2). At low temperatures NH4F and NH4HF2 react with liquid CIF3 when allowed to warm from — 196 to —5° but the reaction is hazardous and may explode above —5° ... 

A solid propellant is a mechanical (heterogeneous) or a chemical (homogeneous, or colloidal) mixture of solid-state fuel and oxidizer-rich chemicals. Specially-formed charges of solid propellant (grains) arc placed in the combustion chamber of the solid rocket motor (SRM) at a production facility. Once assembled, the engine does not require additional maintenance, making it simple, reliable and easy to use. 

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