Classification of Propellants

Hypergolic Non-hypergolic Cryogenic Figure 4.1 Classification of propellants in terms of their applications. 

SB DB NB Composite CMDB Fuel-rich Figure 4.2 Classification of propellants based on their physical state. 

Figure 4.3 Classification of propellants based on their nature.

Classification of Propellents Based on Exhaust Properties. Based on the exhaust properties, solid propellants can be classified as smoky, reduced smoke, minimum smoke, or minimum signature propellants. The description of these categories are listed as follows ... 

MINIMUM SIGNATURE - Propellants whose exhaust characteristics are tailored to give not only minimum smoke properties, but also to have low visible, ultraviolet, or infrared emissions are termed minimum signature propellants. Minimum signature propellants are of interest from the standpoints of launch site and missile detectability and from considerations of through-plume guidance. Fig. 30.16. Classification of propellants based on exhaust properties. 

There are several types of propellant which may be broadly classified on the basis of their application and their physical state. Based on their applications, propellants may be classified as gun propellants or rocket and missile propellants and this classification is shown in Figure 4.1. 

The shelf-life of propellants is evaluated from the stabilizer content and is defined by the period of storage (number of years) in which the stabilizer content is reduced to half of the initial value. Gun propellants of low web size <0.2 mm can burn very fast which may lead to mass detonation and accordingly gun propellants with low web size fall under UN Hazard Classification 1.1 whereas others fall under 1.3 (see Chapter 6). 

Cruice, W.J. (1981) Classification of Liquid Gun Propellants and Raw Materials for Transportation and Storage, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD, Report No. ARBRL-CR-00454. 

Hazard Classification of Solid Propellants , Paper presented at the Specialist Session on Rocket Motor Safety, 26th JANNAF Meeting, Washington, DC (1970) 23) Anon, Properties of... 

It must always be assumed that explosive fumes and propellant fumes are to some extent toxic. Excess oxygen causes the formation of nitrogen oxides, deficiency carbon monoxide, both toxic. In the United States, the following classification of toxic fume components has been accepted a 1 -1/4 by 8" cartridge in its cartridge paper is detonated in a -> Bichel Bomb, and the fume composition is gas analysed. In the following Table toxic gases means the sum CO + H2S (NO and N02 are not considered ) in ft3/lb explosive ... 

The mechanical ways of foam breakdown are realised by various rotating devices (mixers, disks, centrifuges, propellers, etc.) or by employing stream of air, vapour or liquid or by running the foam through cyclones and narrow gaps [1,2]. In all these cases the liquid outflow from the foam is accelerated which creates critical deformations and stresses in films and other foam elements. A convenient classification of the mechanical means of foam breakdown and the methods designing such mechanical devices are considered in [3]. The... 

The objective of this program is to establish hazard classification procedures, as a supplement to the existing regulatory manual, for in-process materials used during the various stages of propellant and explosive manufacture. 

J. Swatosh, Jr., and H. Napadensky, Explosive Hazard Classification of Ml Propelling Charge in its Container, (Vol I II), IITRI TR J6265-27 September 1972... 

An aerosol form of a mixture may be classified in the same hazard category as the tested, non-aerosolized form of the mixture for oral and dermal toxicity provided the added propellant does not affect the toxicity of the mixture on spraying. Classification of aerosolized mixtures for inhalation toxicity should be considered separately. 

Classification of gases by families can sometimes be misleading because individual gases may often be used in a number of very different ways. Nitrous oxide, for example, belongs to several families—it is a prominent member of the medical gases family, is used as a propellant gas, and also is used as a refrigerant gas. 

The type of rotating element or wheel that is used to move the air or gas can classify centrifugal fans. The major classifications are propeller and axial. Axial fans also can be further differentiated by the blade configurations. 

Class B Explosive Under the U.S. Department of Transportation (DOT) safety regulations, as per 49 CFR 173.88, Class B explosives are defined as those explosives which in general hmction by rapid combustion rather than detonation and include some explosive devices such as special fireworks, flash powders, some pyrotechnic signal devices and liquid or solid propellant explosives which include some smokeless powders. The regulations provide specific descriptions of and tests for Class B explosives. Refer to Classifications of Explosives. 

---