Torsion balance

Very High Pressures Use balanced o-ring cartridge seals up to about 500 psi. Above 500 psi use the tandem double seal with the barrier fluid pressurized at / the seal chamber pressure. Remember as pressure goes up the o-rings will extrude and metal parts will distort. Use a torsion balanced seal. 

Hard Vacuum Use a balanced o-ring seal for industrial vacuum. For absolute pressure less than 1 kpa (1 kilopascal) use a torsion balanced seal. (Must verify this measurement)... 

Dreh-federwage, /, torsion balance, -feld, n. (Elec.) rotating field, -gelenk, n, swivel joint, -geschwindigkeit, /. speed (or velocity) of rotation or of revolution, -impuls,... 

Torsions-faden, m. torsion filament or wire, -festigkeit, /, torsional strength, -kraft, /, torsional force, -spaonung, /, torsional stress, twisting stress, -wa(a)ge,/. torsion balance, winkeh m. angle of torsion. 

As mentioned above, mainly two types of balances are used beam balances and spring or torsion balances. Spring or torsion balances show a special relation between... 

In a typical experiment, a small volume of an insoluble surface-active material (dissolved in a water-insoluble solvent such as benzene) is placed atop a clean water surface. As the solvent evaporates away, a film remains and the moving barrier can be adjusted so that the surface film exerts pressure on the mica float. A calibrated torsion balance is used to measure the force that the film exerts on the float. That force divided by the length of the float is the force per unit length or the surface pressure. For studies of lipolysis kinetics , a Langmuir trough can be constructed so that one can measure lipase action under first-order and zero-order conditions. 

The surface trough was made of Lucite, 45 X 15 X 1.5 cm. and was divided into two compartments of equal size by a septum of Lucite, 1.5 cm. high. Cooling channels for temperature control were milled into the bottom of the trough. The monolayer was spread inside a paraffined mica frame which floated on the water and was firmly positioned by external mounts. The surface tension was measured with a double-hook torsion balance and a sand-blasted platinum Wilhemy plate. A Beckman model G pH meter with standard glass and KC1 electrodes was used to measure pH. 

Cavendish is also known fur a sensitive torsion balance, known as the Cavendish balance, (o measure the value of the gravitational constant, which delines the strength of the force of gravity. 

Electric well logging first used in United States refraction seismograph graph used to discover Orchard, Texas, salt dome first geophysical discovery using magnetic torsion-balance. 

Figure 24. Conformational states (folded and unfolded) for Wilcox molecular torsion balance...

The exact calculation of the weight of liquid lifted, in terms of the surface tension and density, is difficult and requires usually special solutions of the fundamental equation of Capillarity, for figures which often are not figures of revolution. The pull may reach a maximum some distance before the object is completely detached and the measurement of this maximum is considered more satisfactory than that of the pull at the moment of detachment.7 In most cases, however, the pull is applied by means of a torsion balance, and the upward motion of the object cannot be checked after the maximum pull is past, so that the detachment takes place almost immediately the maximum pull is reached. 

In summary, some important properties of torsion balances for surface studies may be emphasized. First, the sensibility of torsion balances... 

---