Stop mark

Problem 17 Integration start/stop marks occur too early or late. 

Stop marks Lines in the weft direction, caused when machine stopped, the yam elongates the tension, results in making across the width. 

Printer machine stop mark Dye smudged along width of fabric as a result of stopping of the printing machine. 

The simplest means of obviating stop marks would be to employ a container holding such a quantity of lead as would be required for the manufacture of the largest and longest cable sheath. This would mean, however, the use of a very powerful and big press, the price of which would be extremely high so that for this very reason cable manufacturers rather prefer to work with a smaller press and to put up with the stop marks. 

Fig. 13a. Corrugated aluminum sheath with stop mark in center of picture after 18 bends over the 20-fold cable diameter. Outside diameter of sheath 07 mm...

Recently there has been developed a continuous hydraulic ram press which, however, is used in the first place for the extrusion of aluminum sheathing, since the stop marks in aluminum sheathing are much more sensitive than those in lead sheathing. 

The idea of developing a continuously operating cable sheathing press, by means of which it is possible to eliminate solidification and waiting periods and to avoid stop marks - the so-called bamboo-rings -... 

A continuous hydraulic aluminum cable sheathing press the design of which has only recently been published, is shown in Fig. 53. With this press which is fed wdth solid billets, it is not so important to save the charging- or waiting time as this is of minor importance as compared with the setting period of lead. It is much more important, however, to obviate the stop marks - or to take measures whieh prevent the cable insulation from charring and eliminate a variation in the wall thickness while the die-block is released. The breath-... 

A cable of the following dimensions is to be extruded from one charge of the container of a cable sheathing press 55 mm outside diameter 1.8 mm wall length I = 110 m emerging speed = 20 m/min without stop mark. 

Therefore, a mathematical model was developed by Strauf et al (2005) that describes the relations between machine settings, fabric properties, and stop mark characteristics. A neural network was trained accordingly. This was used to determine an optimum machine setting in order to minimize the stop mark, thus minimizing the effect of a machine stop on the fabric quality. Table 14.3 shows the predicted characteristics of a stop mark and the measured data. Since the system apparently works, it is now used in industry by weaving machine manufacturers. 

Table 14.3 Comparison between Predicted and Measured Values for Machine Settings to Avoid Stop Marks (Strauf et al, 2005)...

Hydrocarbons are of a lower density than formation water. Thus, if no mechanism is in place to stop their upward migration they will eventually seep to the surface. On seabed surveys in some offshore areas we can detect crater like features ( pock marks ) which also bear witness to the escape of oil and gas to the surface. It is assumed that throughout the geologic past vast quantities of hydrocarbons have been lost in this manner from sedimentary basins. 

Figure A2.1.6. Entropy as a fimction of piston position / (the piston held by stops). The horizontal lines mark possible positions of stops, whose release produees an inerease in entropy, the amount of whieh ean be measured by driving the piston baek reversibly.

Often contain defects (hydrogen cracks, slag inclusions, stop-start marks). Help initiate fatigue cracks. Critical welds must be tested non-destructively and defects must be gouged out. 

Calibrate the detector tube pump for proper volume measurement at least quarterly. Simply connect the pump directly to the bubble meter with a detector mbe in-line. Use a detector mbe and pump from the same manufacturer. Wet the inside of the 100 cc bubble meter with soap solution. For volume calibration, experiment to get the soap bubble even with the zero ml mark of the buret. For piston-type pumps, pull the pump handle all the way out (full pump stroke) and note where the soap bubble stops for bellows-type pumps, compress the bellows fully for automatic pumps, program the pump to take a full pump stroke. 

For either type pump, the bubble should stop between the 95 cc and 105 cc marks. Allow 4 minutes for the pump to draw the full amount of air. Also check the volume for 50 cc (1/2 pump stroke) and 25 cc (1/4 pump stroke) if pertinent. A +5 percent error is permissible. If error is greater than +8 percent, send the pump for repair and recalibration. Record the calibration information required on a calibration log. It may be necessary to clean or replace the rubber bung or tube holder if a large number of tubes have been taken with the pump. 

Hydroxylamines ordinarily do not accumulate in the reduction of aromatic nitro compounds for, with some exceptions, most systems in competition will reduce the hydroxylamine function preferentially. Nonetheless, systems have been found that afford the intermediate aromatic hydroxylamine in excellent yield. With hydrogen gas as a reductant and platinum-on-carbon or -on-alumina and about I wt % of DMSO based on nitro compound as a modifier, aromatic hydroxylamines can be formed in 90% yield under mild conditions. The reduction slows markedly after absorption of the second mole of hydrogen and should be stopped at this stage (80). 

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