Chamber press

Fig. 21. Membrane plate press, ie, recessed plate with variable chamber press.

The diazido compd can be detond by friction. It has an expl temp of 165° a Qc of 825.4 (avg) kcal/mole a Qf of 78.9kcal/mole and an impact sensy of 5.7cm using a 2kg wt and an Aberdeen Impact app with No 12 tools (vs 26.7cm for PETN). Theoretical calcns using the TIGER computer code detdthe flame temp (3120°K), force (4.46 inch-lbs/b) and chamber press (39800 psi) of M-2 proplnt when the drazide was substituted for NG in the formulation, (19.34%). 

The filter press is one of two main types, the plate and frame press and the recessed plate or chamber press. 

Not all expls and propellants that are acidic show low stability when subjected to the ordinary heat tests. However, such acidic compds usually igpite more readily than neutral substs. In the case of acidic propellants some irregularity in burning may be observed. In many cases such propellants bum completely and exhibit abnormalities in chamber press and range in firing tests... 

Semicarbazide Hydrochloride (Amidourea hydrochloride). CHsON3.HC1 mw 111.52 N 37.69% OB to C02 —57.39% colorl prisms or snow-white crysts mp 173°, 175—77° (sep values, decompn). V sol in w sol in dQ ethanol insol in absol ethanol and eth, Prepn is by electrolytic redn of nitrourea with cathodes of Cu, Ni, Pb and Hg in hydrochloric acid soln (Refs 1 7). CA Registry No [56341-7]. The hydrochloride is used in rubber-Amm perchlorate solid proplnts in amounts of from 0.1 to 10% as a burning rate depressant. At 300psi chamber press the hydrochloride is reported to effect a 31% depression in the burning rate (Ref 6)... 

Jensen Webb (Ref 43) examined the data predicting the extent of afterburning in fuel-rich exhausts of metal-modified double-base proplnt rocket motors so as to determine the amt of an individual metal which is required to suppress this afterburning. The investigatory means they used consisted of a series of computer codes. First, an equilibrium chemistry code to calculate conditions at the nozzle throat then a nonequilibrium code to derive nozzle plane exit compn, temp and velocity and, finally, a plume prediction code which incorporates fully coupled turbulent kinetic energy boundary-layer and nonequilibrium chemical reaction mechanisms. Used for all the code calcns were the theoretical environment of a static 300 N (67-lb) thrust std research motor operating at a chamber press of S.SMNm 2 (500psi), with expansion thru a conical nozzle to atm press and a mass flow rate... 

Composition, (Wt%) Grain d,g/cc Grain Diam, inches Reaction Prod, Gaseous Liquid Combustion Chamber Press, psia Adiabatic Flame Temp, °K... 

These media are described as two-sided, with an upper slick surface for filtration being produced by a sateen weave. This surface is fiuther modified by calendering. Another important feature of this design is that ultrafines are not retained by the cloth, being released downstream by the underside fiumel-shaped pores. A published industrial report [Technical Textiles International, 1992] refers to success with this type of cloth (monofilament polyester, calendered to screen size 30 pm) in high- pressure variable chamber pressing of dyestuff hydroxides, stearates, etc. 

Hongxiaiig, 1991] refer to a cake moisture reduction to less than 25% as being necessary for effective cake discharge. Low moistures in variable chamber pressing of dyestuffs, metallic hydroxides and stearates followed the use of monofilament polyester cloth calendered to reduce the screen size to 30 pm [Reid, 1974], as mentioned above. Carleton and Heywood [1983] have discussed the fundamental aspects of filter cake properties and cake discharge mechanism. The effectiveness of discharge will dq>end on ... 

Grotq> C Variable-chamber presses containing means of squeezing the solids after... 

Continuous belt presses. Figure 11.44, compete widi solid-bowl centrifuges and variable-chamber presses in ndge dewatering applicatioits. Table 11.11 presents ical productivities of such units it can be seen that each of these units has advarrtages and disadvantages. Usually, a clear optimum choice of filter is difiScuh to identify. 

Lift the die set carefully by holding onto the lower anvil so that the collar stays in place. If you are careless with this operation, the collar may move enough to allow the powder to escape. Open the handle of the handpress slightly, tilt the press back a bit, and insert the die set into the press. Make sure that the die set is seated against the side wall of the chamber. Close the handle. It is imperative that the die set be seated against the side wall of the chamber so that the die is centered in the chamber. Pressing the die in an off-centered position can bend the anvil pins. 

Excluding variable chamber presses, which rely on mechanical squeezing of the cake and which are dealt with in the following section, presssure filters may be grouped into two categories, plate-and-frame filter presses and pressure vessels containing filter elements. 

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