Valves cylinder

Acetylene cylinders are fitted with safety devices to release the acetylene ia the event of fire. Cylinders manufactured ia the United States are equipped with safety devices which contain a fusible metal that melts at 100°C. In large cylinders the safety devices are ia the form of a replaceable, threaded steel plug with a core of fusible metal. Small cylinders (0.28 and 1.12 m 10 and 40 fT, respectively) may have the fusible metal ia passages ia the cylinder valve. 

The compressor cylinder valves are of the spring-loaded, gas-actuated type in all but a limited number of portable compressors. This kind of... 

Replace the correct caps or guards on cylinder valves when not in use and for return to the supplier. 

Never change a cylinder without first closing the cylinder valve and extinguishing naked lights in the vicinity. 

Keep regulators, valves and piping on compressed gas systems clean and free from oil and grease Close the cylinder valve when not in use... 

The major source of fugitive emissions from a gas compressor cylinder is the piston rod packing. Other sources of fugitive emissions are around the cylinder valve covers, unloader covers, unloader actuator packing, and clearance pocket gasket and actuator packing. 

Using iodine as their starting point, they experimented with a series of compounds including the anilines and a series of metals near the bottom of the periodic table. Lead turned out to be the most effective of the additives tested. But lead alone caused a number of problems, including the accumulation of Its oxide in engine components, and particularly the cylinders, valves, and spark plugs. 

Equipment Failure pumps, tubes in heat exchangers and furnaces, turbine drivers and governor, compressor cylinder valves are examples of equipment which might fail and cause overpressure in the process. If an exchanger tube splits or develops a leak, high pressure fluid will enter the low side, overpressuring either the shell or the channels and associated system as the case may be. 

The valve plates, discs, and springs are mounted in a valve cage, which is inserted in the cylinder. Valve breakage occurs due to fatigue of the metal or improper action. This requires replacement and an evaluation of the materials of construction as well as the basic type of valve. Each manufecturer presents his valve design to match his equipment. Only experience can determine which type of valve works best in a given application... 

Figure 12-17B. Effects of clearance volume on performance efficiency of reciprocating compressor cylinder (valve design effect). (Used by permission Livingston, E. H. Chemical Engineering Progress, V. 89, No. 2, 1993. American Institute of Chemical Engineers, Inc. All rights reserved.)...

Compression efficiency is the ratio of the work required to adiabatically compress a gas to the work actually done within the compressor cylinder as shown by indicator cards. Figures 12-12 and 12-16. The heat generated during compression adds to the work that must be done in the cylinder. Valves may vary from 50-95% efficient depending on cylinder design and the ratio of compression. Compression efficiency (or sometimes termed volumetric efficiency) is affected by several details of the systems ... 

A general appreciation of some of the effect of gas pulsation on the performance and impact on the compressor pulsation drums, their nozzles, the piping system, and the cylinder valve performance, as well as possible other effects in some unique systems or items of equipment, can be discovered by examining the cylinder performance using an indicator card. This examination (see Chapter 12) can reveal acceptable and unacceptable performance in terms of pressure variations within the cylinder as the piston passes through its cycle. Hicks presents a helpful analysis see Figures 13-3 and 13M. 

Butane cylinders, which are so widely used for domestic service, are now provided with a self-sealing clip-on valve. The pressure regulator, which is normally attached directly onto the cylinder outlet, is fitted by a simple push-on or snap-on action and is provided with a lever, which will open or shut the cylinder valve. 

When the equipment is turned off, close the fuel gas cylinder valve tightly and bleed the gas line to the atmosphere via the exhaust system. 

At the end of each work day, one person in the laboratory should have the responsibility for turning off the main cylinder valves for all gases. 

Ensure that empty cylinders have the valve closed to prevent evaporation of acetone. Close cylinder valve before shutting off regulator, to permit gas to bleed from regulator. When used e.g. for welding, avoid the careless use of flame which could fuse the metal safety plug in the cylinder. 

Close cylinder valve before shutting off regulator, to permit gas to bleed from regulator. 

Ensure feat the pressure adjusting screw of a pressure regulator is fully unwound, so feat fee regulator outlet valve is closed before opening fee oxygen cylinder valve. 

Ensure feat the cylinder valves are closed and piped supplies isolated whenever work is stopped. 

Reciprocating compressors compress gases by a piston moving backwards and forwards in a cylinder. Valves control the flow of low-pressure gas into the cylinder and high-pressure gas out of the cylinder. The mechanical work to compress a gas is the product of the external force acting on the gas and the distance through which the force moves. Consider a cylinder with cross-sectional area A containing a gas to be compressed by a piston. The force exerted on the gas is the product of the pressure (force per unit area) and the area A of the piston. The distance the piston travels is the volume V of the cylinder divided by the area A. Thus ... 

Anon., Lab. Accid. Higher Educ. Item 32, HSE, Barking, 1987 During the reduction of the azide in ethanol with hydrogen sulfide (no regulation other than main cylinder valve) under reflux (with insufficient flow of condenser water), the mixture apparently overheated, then exploded violently. 

Two liters of toluene are added to the reaction flask and the boron trichloride cylinder is placed on a balance. The reaction flask is then cooled with a Dry Ice-ethanol or Dry Ice-acetone mixture. The gas cylinder valve is opened, and the boron trichloride is condensed in the toluene. After 117 g. (1 mol) of boron trichloride has been introduced, the cylinder valve is... 

What if the cylinder valve cannot be closed during an emergency ... 

Lantern rings for pumps, bellow-type seals for centrifugal pumps hydraulic, pneumatic, earthmoving equipment cylinder valves for O2, CO2, refined gases, chlorine, ammonia... 

Prior to leaving the lobby for fire-suppression activities, all members will be wearing full personal protective equipment including SCBA, and will have cylinder valves opened. In addition, each person will have a personal light along with hand tools prior to entering the stair tower for suppression operations. 

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