Spring-loaded cylinders

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

Other modifications that have been produced include incorporating a cavity or minifumace into the rod. This was accomplished by placing a hollow-cathode cylinder or a graphite cup between two spring-loaded rods. These mini-furnaces could cope with samples of up to 20 mm, or in some cases solid samples could also be analysed. 

Both the discharge valve and the intake or suction valve are simply spring-loaded check valves. The discharge valve permits gas only to be forced out of the cylinder. The intake valve permits gas only to enter the cylinder. 

As soon as the piston reverses its direction of travel, the pressure of the gas inside the cylinder drops. The gas pressure drops below the discharge line pressure, and the spring-loaded discharge valve slams shut. The piston continues its travel toward the crank end of the cylinder. The pressure of the gas inside the cylinder continues to fall, but the suction or intake valve remains closed. 

The permeation experiments were carried out on 2 cm thick clay specimens placed into an aluminium cylinder of 5.38 cm diameter. The testing equipment allows the generation of a constant flow rate using a piston moving at a constant velocity. The chamber of the piston is connected to the fluid chamber in the permeameter cell located above the clay specimen, which is toped by a porous stone. A pressure transducer is connected to the hydraulic circuit. The fluid outlet in the lower aluminium plate is kept at atmospheric pressure. An external vertical load is applied to the specimen by means of a spring-loaded cap prior to permeation. Vertical settlements are monitored using a dial gauge and a settlement rod mounted on top of the specimen. 

Viscosity is a property sometimes difficult to assess, as figures can be measured on any one of several types of viscometer. One common type is the rotating disk viscometer, which must be used in a container big enough to eliminate wall effects. The main alternative is the cup-and-bob viscometer, where the viscous drag of the liquid between stationary and rotating concentric cylinders is indicated by a spring-loaded pointer moving over a dial. 

Fig. 24.3 Cylinder that uses a spring-loaded piston to press upon a gas contained in it.

Gas pressure was maintained in the cell by placing spring loaded pressure relief valves at the outlets. The effluents were bled into lOmL graduated cylinders to collect the water effluent. Tees were placed in the outlet lines with relative humidity sensors in the dead legs of the tees. The water content of the outlet streams was measured with humidity sensors (Sensirion SHT7X). 

Cylinders are devices that engineers can use in their design. The cylinders in Figure 11-15 can both extend and retract. Engineers would use a two-way control valve to direct the pressurized fluid to one or the other side of the cylinder. Other types of cylinders, such as those shown in Figure 11-16, are spring loaded so that they will automatically return once the fluid power is released. 

All pressure regulators should be equipped with spring-loaded pressure-relief valves (see section 6.D.2.2.1 for further information on pressure-relief devices) to protect the low-pressure side. When used on cylinders of flammable, toxic, or otherwise hazardous gases, the relief valve should be vented to a hood or other safe location. The use of internal-bleed-type regulators should be avoided. Regulators should be removed from corrosive gases immediately after use and flushed with dry air or nitrogen. Mercury bubblers should not be used. 

High pressure is perhaps the most important hazard of a gas stored in the cylinder. A typical gas cylinder usually comes filled at a pressure of around 2200-2400 psi (pounds per square inch) (see Special Topic 5.3.1.1 Pressure Units). Upon the sudden release of this pressure the gas can be very dangerous. Of course, as the temperature rises in the laboratory or place where the cylinder is stored, the cylinder pressure also rises, and the greater the pressure the more stress there is on the integrity of the cylinder. To take measures to prevent explosions, manufacturers install a relief valve that is designed to rupture at some prescribed cylinder pressure, temperature, or combination of temperature and pressure. Most of these relief devices open when a disk raptures or melts. Less commonly, a spring-loaded relief valve is installed that can open at some high pressure and reclose when the cylinder pressure is reduced. 

Floating Archimedes principle, as for pressure, cylinder pistons, spring-loaded plug, diaphragm, Doppler, Coriolis... 

Based on the NIST cell, this DAC [10] uses a spring-loaded lever-arm mechanism for generating the force, but is considerably larger and is used in an inverted configuration as shown in Fig. 4a. For stable anvil alignment this cell uses a long 60-70mm detachable piston-cylinder assembly (Fig. 4b). 

Type CG-7 (pressure relief valves), A pressure relief valve is a spring-loaded, pressure operated device designed to relieve excessive cylinder pressure, reclose, and reseal to prevent further release of product from the cylinder after the cause of excessive pressure is removed and valve reseating pressure has been achieved. 

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