Interlock, interlocking

Interlocks Interlocks are another important feature of a well-designed control and instrumentation system. Interlocks are intended to prevent damage to the dryer system or to personnel, especially during the critical periods of start-up and shutdown. The following are a few key interlocks to consider in a typical dryer system. 

In the case of the WWER NPPs, the polar crane in the reactor building lacks adequate interlocks. Interlocking is required to prevent the simultaneous transport of heavy loads over the reactor and spent fuel pool and a decoupling of the crane forks and hooks. 

The access by personnel to areas of high dose rates or high levels of contamination should be controlled by the provision of lockable doors and, where appropriate, the use of interlocks. Interlocks are provided to ensure that access is only possible when radiation levels are acceptably low and they should be designed to provide an alarm if they become inoperative. 

When a block is inside, the entrance panel is closed and the inspection is ready to start. The inside of the stainless steel X-ray tubehead housing is clad in lead with an on/ofT shutter in front of a thin plastic X-ray window. The thin window is to ensure the IP 65 classification. The window is of plastic that is not affected by the cleaning agents. The on/off shutter is interlocked with the entrance and exit panels so X-rays can be kept on at all times without risk of radiation leakage or exposure of the frozen fish blocks prior to the actual inspection. 

The accept and downgrade buttons are interlocked with a sensor device, so that a block must be scanned at least once before the block can be accepted and loaded out by the operator This function will however always be overruled by the programmed safety time limit, which will automatically reject and outload the block when the allowed exposure time has elapsed. 

The cabinet system includes full radiation safety in the form of dual, forced breaking door interlocks so that there can be no risk of exposure outside the cabinet. Equally the system is equipped with emergency stops and red lights indicating when X-rays are on, in accordance with the international regulations. 

The entire x-ray exposure cabinet including it s extension into the lower electrical cabinet is shielded with a minimum of one-inch of steel clad, lead plate with fiilly welded (fused lead) joints. The safety interlock switch on the cam-lock inter-face ... 

Alternatively the ion exchanger may be a synthetic polymer, for example a sulphonated polystyrene, where the negative charges are carried on the —SO3 ends, and the interlocking structure is built up by cross-linking between the carbon atoms of the chain. The important property of any such solid is that the negative charge is static—a part of the solid—whilst the positive ions can move from their positions. Suppose, for example, that the positive ions are... 

Knitted fabrics are produced from one set of yams by looping and interlocking processes to form a planar stmcture. The pores in knitted fabrics are usually not uniform in size and shape, and again depend largely on yam dimensions and on the numerous variables of the knitting process. Knitted fabrics are normally quite deformable, and again physical properties are strongly dependent on the test direction. 

Within the plane of a nonwoven material, the fibers may be either completely isotropic or there may be a preferred fiber orientation or alignment usually with respect to a machine or processing direction. In the case of thicker dry-laid nonwovens, fiber orientation may be randomized in the third dimension, ie, that dimension which is perpendicular to the plane of the fabric, by a process known as needle-punching (7). This process serves to bind the fibers in the nonwoven by mechanical interlocking. 

Fig. 4. Fracture surface (repHca micrograph) of fluorcanasite glass-ceramic showing interlocking blade-shaped crystals and effects of cleavage splintering...

The next step is to apply a number of loss control credit factors such as process control (emergency power, cooling, explosion control, emergency shutdown, computer control, inert gas, operating procedures, reactive chemical reviews), material isolation (remote control valves, blowdown, drainage, interlocks) and fire protection (leak detection, buried tanks, fire water supply, sprinkler systems, water curtains, foam, cable protection). The credit factors are combined and appHed to the fire and explosion index value to result in a net index. 

Later than 2. Operator error 1. Temperature rises, possible 1. Interlock between cooling flow and JEH 1/93... 

Lead bricks are generahy used as temporary shields for radiation sources at nuclear power stations, research institutes, hospitals, and fuel reprocessing plants. Plat, rectangular bricks requite a double layer with staggered seams whereas the interlocking bricks requite only one course. Lead shot can be poured into inaccessible areas like a Hquid. 

Friction during dry sliding primarily involves a force F required to displace interlocking asperities of the softer material with shear strength s. 

Pour-Point Depressants. The pour point of alow viscosity paraffinic oil may be lowered by as much as 30—40°C by adding 1.0% or less of polymethacrylates, polymers formed by Eriedel-Crafts condensation of wax with alkylnaphthalene or phenols, or styrene esters (22). As wax crystallizes out of solution from the Hquid oil as it cools below its normal pour point, the additive molecules appear to adsorb on crystal faces so as to prevent growth of an interlocking wax network which would otherwise immobilize the oil. Pour-point depressants become less effective with nonparaffinic and higher viscosity petroleum oils where high viscosity plays a dominant role in immobilizing the oil in a pour-point test. 

A nonwoven fabric can be assembled by mechanically, chemically, or thermally interlocking layers or networks of fibers, filaments, or yams. Fabrics made from textile fibers in this manner have been classified as dry-laid nonwovens. 

From a practical standpoint, the fiber or polymer must interact or process freely with the dynamics of web formation, and the resulting fiber network must be in register with the interlocking arrangement or media, in order for the fabric stmcture to transmit the maximum potential inherent in the properties of individual fibers. Ultimately, if a nonwoven fabric is to be totally effective and its properties fuUy utilized, it must be appropriately configured to meet its end use apptication or appropriately placed in the end use item in such a way that the performance of the product reflects the position and characteristics of individual fibers. 

A needled felt, on the other hand, is a fabric composed of natural, synthetic, or a combination of natural and synthetic fibers physically interlocked by the action of a needle loom with or without combination of other textile fabrics and with or without suitable combination of mechanical work, chemical action, moisture, and heat, but without weaving, knitting, stitching, thermal bonding, or adhesives (16). 

Chemical binders are appHed to webs in amounts ranging from about 5 to 60 wt %. In some instances when clays (qv) or other weight additives ate included, add-on levels can approach or even exceed the weight of the web. Waterborne binders ate appHed by spray, saturation, print, and foam methods. A general objective of each method is to apply the binder material in a manner sufficient to interlock the fibers and provide chemical and mechanical properties sufficient for the intended use of the fabfic. 

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