Roll metering

Preparation of definite powder metallurgy manufacture of spheres by planetary rolling metering, dispensing, and... 

Fig. 11. Reverse-roll, metered film thickness on the applicator roll divided hy gap, tJG, as a function of the ratio of the metering roll speed to applicator roll speed for various capillary numbers based on 17a- (—) represents theoretical values ( ) experimental ones and (----) is the lubrication model (12).

In knife-over-roll or blade coating, the coating material is placed on the fabric surface behind a knife, or doctor blade, and metered according to the gap set between the blade and the fabric surface. This method is used to apply thick coatings of highly viscous materials such as pastes, plastisols, or foams. 

Kiss-Roll Colters. In kiss-roU coating, the web passes over a roU wet with the coating fluid, and has no backing roU. There are many types of kiss-roU coaters. The kiss roU can turn in the dkection of the web or in the reverse dkection but usually operates in the web dkection. Kiss-roU coaters are tension sensitive and are often used to apply excess coating prior to a metering device. 

There are different coating techniques. The woven and nonwoven fabrics normally involves three steps as it passes from the unwind roll to the rewind roll. Powder is metered onto the fabric, heated in an oven (gas or electric) that are usually divided into several heating zones, and cooled by a chill roll. 

With their Models 763 and 764 microprocessor-controlled pH meter, Knick deliver and adapted Model 790 serial printer this yields in a simple way by means of an AC-synchronous clock and two adjustment knobs a hard copy of measurements at intervals of 2, 5, 10, 30 or 60 s or minutes printed out in a 32.5-mm rule of 12 positions on a small paper roll. 

The film is wound to film rolls using a contact/surface winder with an option for automatic roll change (Fig. 9, 4). The production process can be controlled automatically, keeping meter weight and thickness distribution constant (Fig. 9, 5). This device enables automatic quality control in the production process. 

Fig. 11 Foamed sheet extrusion line. 1 Primary extruder, 2 blowing agent metering and flow control, 3 screen pack/breaker plate, 4 secondary extruder, 5 annular die, 6 cooling mandrel, 7 guide rolls, 8 winders. [38]...

Some of the early Thiokol solid rubbers are still made and used in printing rolls, solvent-resistant spray hose, gaskets, and gas-meter diaphragms. Many of the polysulfide products have been in use since the 1940s with an excellent track record. Continuing improvements in technology keep these products competitive. 

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