Air-gap

A crack in concrete with an air gap thickness of as little as 0.025 mm will hinder significant transmission of seismic compression waves [1]. 

Fig. 10. Cross section of an EMFC weighing cell. Item 1, pan 2, hanger 3, parallel guide 4, chassis 5, flexure 6, lever 7, flexible link 8, pivot point 9, position indicator 10, position sensor 11, permanent magnet 12, permanent magnet air gap 13, compensation cod. See text.

Eig. 7. Extmsion of roU-cast film A, die inlet B, cast-film die C, air gap with molten web D, casting roU E, stripping roU E, idler roU G, edge-trim sHtter ... 

In contrast to most extmsion processes, extmsion coating involves a hot melt, ca 340°C. The thin web cools rapidly between the die and nip even at high linear rates. Both mechanical and chemical bonding to substrates are involved. Mechanical locking of resin around fibers contributes to the resin s adhesion to paper. Some oxidation of the melt takes place in the air gap, thereby providing sites for chemical bonding to aluminum foil. Excessive oxidation causes poor heat-sealing characteristics. 

The coatact betweea the two objects is aot required to be a physical touchiag of the two objects. If the charge oa the object is greater than the dielectric strength of air, the charge will pass over the air gap to the other object. 

The power transferred by the stator to the rotor, P, also known as air gap power at synchronous speed, can be expressed in kW by ... 

The mechanical clearance between rotating parts, e.g., fan and fan cover or the radial air gap between the stator and the rotor, should not be less than specified to prevent sparking. 

Note The shaft deflection should not be more lhan 11% of the air gap between the stator and the rotor. For loads that exert more force and torsional stress on the motor shaft and bearings than is permissible, due to the larger width of pulleys which may shift the... 

Sometimes, as a result of an unbalanced magnetic field, causing an air gap eccentricity or excessive shaft deflection, the motor is not able to maintain the small air gap between the rotor and the stator and this may lead to failure. 

Check bearings and air gap during maintenance, at least once a year. 

Unlike an air core, the inductor coil now has an iron core that may be provided with air gaps or non-magnetic... 

Similarly, gapped iron core reactors as shown in Figure 27.4, in which the iron core content is reduced by providing an air gap or non-magnetic material between the core laminations, also raise the saturation level (the core remaining unsaturated. Figure 27.1 I) to help provide an... 

Fig. 8-3 ac voltage, U, in a current-limiting choke as a function of the ac flowing through it, /, for different numbers of windings, w, with and without an air gap. 

---