Pressure guard

The Megaject Mark II injection system, from Plastech IT, offers facilities such as pre-setting the amount of catalyzed resin to be injected (pre-determining counter), pre-setting safe nozzle pressure (mold pressure guard), catalyst flow sensor and auto-stop (Catal), and automatic valve and controller (autosprue). 

Relief systems are expensive and introduce considerable environmental problems. Sometimes it is possibly to dispense with relief valves and all that comes after them by using stronger vessels, strong enough to withstand the highest pressures that can be reached. For example, if the vessel can withstand the pump delivery pressure, then a relief valve for overpressurization by the pump may not be needed. However, there may still be a need for a small relief device to guard against overpressurization in the event of a fire. It may be possible to avoid the need for a relief valve on a distillation column... 

Chill the concentrated solution of the amine hydrochloride in ice-water, and then cautiously with stirring add an excess of 20% aqueous sodium hydroxide solution to liberate the amine. Pour the mixture into a separating-funnel, and rinse out the flask or basin with ether into the funnel. Extract the mixture twice with ether (2 X25 ml.). Dry the united ether extracts over flake or powdered sodium hydroxide, preferably overnight. Distil the dry filtered extract from an apparatus similar to that used for the oxime when the ether has been removed, distil the amine slowly under water-pump pressure, using a capillary tube having a soda-lime guard - tube to ensure that only dry air free from carbon dioxide passes through the liquid. Collect the amine, b.p. 59-61°/12 mm. at atmospheric pressure it has b.p. 163-164°. Yield, 18 g. 

Carrying out a combustion. The apparatus (Fig. 85, p. 469) will have been left with the bottle W connected to the beak of the combustion tube via the guard tube V and with all the taps shut, the combustion tube, which is dways allowed to cool down while connected to the oxygen source, will therefore be full of oxygen at slightly above atmospheric pressure, thus preventing any leaking in of carbon dioxide or water vapour from the air. 

Boil a mixture of 10 g. (10 ml.) of o-toluidine and 38 g. (35 ml.) of acetic anhydride in a 75 or 100 ml. Claisen flask fitted with a reflux condenser (Fig. Ill, 28, 1, but with trap replaced by a calcium chloride or cotton wool guard tube) for 1 hour. Arrange the flask for distillation under reduced pressure (compare Fig. II, 20, 1) and distil acetic acid and the excess of acetic anhydride pass over first, followed by the diacetyl derivative at 152-153°/20 mm, some mono-acetyl-o-toluidine (1-2 g.) remains in the flask. The yield of diacetyl-o-toluidine is 14-15 g, it is a colourless, somewhat unstable hquid, which slowly sohdifies to yield crystals, m.p. 18°, To prepare the (mono-) acetyl-o-toluidine, warm a mixture of 5 g. 

Ethyl phenylethylmalonate. In a dry 500 ml. round-bottomed flask, fitted with a reflux condenser and guard tube, prepare a solution of sodium ethoxide from 7 0 g. of clean sodium and 150 ml. of super dry ethyl alcohol in the usual manner add 1 5 ml. of pure ethyl acetate (dried over anhydrous calcium sulphate) to the solution at 60° and maintain this temperature for 30 minutes. Meanwhile equip a 1 litre threenecked flask with a dropping funnel, a mercury-sealed mechanical stirrer and a double surface reflux condenser the apparatus must be perfectly dry and guard tubes should be inserted in the funnel and condenser respectively. Place a mixture of 74 g. of ethyl phenylmalonate and 60 g. of ethyl iodide in the flask. Heat the apparatus in a bath at 80° and add the sodium ethoxide solution, with stirring, at such a rate that a drop of the reaction mixture when mixed with a drop of phenolphthalein indieator is never more than faintly pink. The addition occupies 2-2 -5 hoius continue the stirring for a fiuther 1 hour at 80°. Allow the flask to cool, equip it for distillation under reduced pressure (water pump) and distil off the alcohol. Add 100 ml. of water to the residue in the flask and extract the ester with three 100 ml. portions of benzene. Dry the combined extracts with anhydrous magnesium sulphate, distil off the benzene at atmospheric pressure and the residue under diminished pressure. C ollect the ethyl phenylethylmalonate at 159-160°/8 mm. The yield is 72 g. 

Storage and Handling. The acid should never be allowed to stand in a line completely sealed between two closed valves or check valves. Excessive pressure caused by thermal expansion of the Hquid can cause leaks or pipe mptures. AH lubricants and packing materials in contact with chlorosulfuric acid must be chemically resistant to the acid. Elanged connections are recommended over screwed fittings and flange guards should be used. 

Portable tanks for regulated commodities in marine transportation must be designed and Built under Coast Guard regulations (see discussion under Pressure Vessels ). 

Pressure vessels carried aboard United States-registered ships must conform to rules of the U.S. Coast Guard. Subchapter F of Title 46, Code of Federal Regulat ions, covers marine engineering. Of this. Parts 50 through 61 and 98 include pressure vessels. Many of the rules are similar to those in the ASME Code, but there are differences. 

These can be converted to their sodium salts by precipitation below 30° with aqueous 25% NaOH. The salt is then decomposed by addition of solid (powder ) carbon dioxide and extract with low-boiling petroleum ether. The solvent should be removed under reduced pressure below 20°. The manipulation should be adequately shielded at all times to guard against EXPLOSIONS for the safety of the operator. 

Ethyl chloroformate [541-41-3] M 108.5, m -81 , b 94-95 , d 1.135, n 1.3974. Washed several times with water, redistd using an efficient fractionating column at atmospheric pressure and a CaCl2 guard tube to keep free from moisture [Hamilton and Sly J Am Chem Soc 47 435 1 925 Saunders, Slocombe and Hardy, J Am Chem SocT3 3796 1951]. LACHRYMATORY AND TOXIC. 

Tail rods are dummy rods that protrude from the head end of the cylinder (see Figure 3-9). The purpose of the rod is to pressure-balance a piston or to stabilize a particular piston design. Because of the personnel hazard, a guard must be specified and provided. In a tandem cylinder arrangement, the outboard cylinders are driven with a rod similar to the tail rod... 

The measured pressure drops were slightly greater than literature data would indicate for packed carbon beds. However, they are certainly not prohibitive and a successful outcome of the Westinghouse trial of the SOFC guard bed is anticipated. 

Comparison of the volume/volume composition data with the relative pressure data shows that although C2-C4 hydrocarbons are present to the greatest volume percent, their actual pressures are an order of magnitude lower than the C5 plus hydrocarbons. Hence, the C5 plus hydrocarbons would be adsorbed in preference to the C2-C4 hydrocarbons and would displace them over a number of cycles. It is apparent therefore that the C5 plus hydrocarbons must be considered the primary target gases for pre-adsorption in guard bed systems... 

Inspections, e.g. pressure systems, trips, relief devices, guards, lighting (see inspection and testing)... 

The vent sizing package (VSP) was developed by Fauskes Associates, Inc. The VSP and its latest version VSP2 employ the low thermal mass test cell stainless steel 304 and Hastelloy test cell with a volume of 120 ml contained in a 4-1, high-pressure vessel as shown in Figure 12-13. The typical ([t-factor is 1.05-1.08 for a test cell wall thickness of 0.127-0.178 mm. Measurements consist of sample temperature Tj and pressure Pj, and external guard temperature Tj and... 

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