Operation Grapple

This article discusses the incineration of PVC wastes, which it reports is facing renewed scrutiny in the UK in the light of numerous breaches of emission limits for hydrogen chloride. The issue is likely to attract further attention as operators grapple with tighter hydrogen chloride controls proposed in the draft EC Directive on incineration. EUROPEAN COMMISSION UK,ENVIRONMENT AGENCY... 

Wheeled Forwarder A frame steered, self-loading vehicle equipped with hydraulically operated grapple and loading boom and a carrier or bunk to support its load of logs. Power requirements vary from 40 to 100 horsepower depending on size. 

The first tests were carried out in 1957 at Operation Grapple in the middle of the Pacific, in what was probably the largest peacetime post-war operation ever undertaken by the services (and notable for the large number of National Service persoimel involved — National Service being a form of conscription for young men, soon to be abolished). AH the tests were carried out as air drops from a Valiant bomber, high over the Pacific, so as to minimise fallout. The devices themselves were all fitted inside the Blue Danube bomb casing. 

We tell students, particularly in thermodynamics, that they need to be attentive to the conditions under which particular equations are valid. It is equally critical for instructors to consider the conditions in which we are operating The key structural pieces of most physical chemistry courses are the text, the problems we assign, and the time instructors and students have to grapple with the reading and working of problems. 

Loader A hydraulically operated boom and grapple which can be mounted on a truck chassis. It is used to gather logs or tree lengths from a pile and build a load on a truck body. 

The CLEM operator controls all machine operations from the control console in the cab mounted on the transporter trolley. The control of CLEM is semiautomatic that is, operations are performed automatically after the operator initiates a command. Interlocks to control the machine s operations have been incorporated into the design to meet safety requirements. Manual overrides are also provided to permit the operator to take control if necessary. The grapple speed and push-pull load requirements in handling fuel are controlled through all modes of operation. Indexing of the CLEM to a refueling station is accomplished by manually operated controls. 

The major subassemblies of the CLEM include the grapple drive system, cask body modules, service platforms, a movable closure valve that mates with the floor valve, the cold-wall assembly, and a seal monitoring system. It also has a variety of special features for other required test-reactor operations such as moving test assemblies from the closed loops to the examination cell and assisting of the disassembly of the fuel within the cell. 

The cask provides the shielding, inert environment, confinement, component grappling, andl.4-kW(t) cooling capability required to handle sodium-wetted, irradiated core components. Its inside diameter isabout 8 in. The dolly provides traverse drive, cask elevation, and seismic-restraint functions. The control system provides the control consoles, motor control equipment, and all interconnecting cables. Control of the transfer cask is semiautomatic that is, key operations are automatically performed after the operator initiates a command. Interlocks are incorporated to meet safety requirements. Status lights indicate the exact machine conditions during all operations and manual overrides permit the operator to complete key operations in case of a control system failure. 

Operating experience shows that mechanical failures of grapples and lifting devices or improper operation of such equipment has led to situations where assemblies were dropped, or struck structures or other assemblies. However, actual damage of the fuel (or release of radioactivity) has been very limited, (see also IH 7, Need for assessment of dropping heavy loads). 

Without the opportunity to properly develop as a discipline, nuclear engineering, as the segment of NSE that deals most directly with nuclear plant operations, possibly never developed the educational capacities necessary to grapple with the challenges posed by climate change. 

The intent is to grapple with the unknown and win to determine a methodology for predicting, more accurately than before, the kind of problems which new technology or new operational practices may bring. 

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