Locking device

These screws and bolts eliminate the need for nuts and washers and so provide cost savings. Common types incorporate a nylon insert, either as a small plug or as a strip along the length of the thread. Fig. 12.7(a). A development of this principle is the application of a layer of nylon over a patch of thread. As the screw is engaged in the mating part, the nylon is compressed and completely fills the space between thread forms. This provides an interference which will resist rotation of the screw. Fig. 12.7(b). A more recent development is the application to an area of thread of a chemical adhesive which is completely dry to the touch. Fig. 12.7(c). The liquid adhesive is encapsulated within the film. When the two threaded parts are assembled, the micro-capsules of adhesive are broken, releasing the adhesive, which hardens and provides a reliably sealed and locked thread. 

The simplest method of locking a nut in position is by applying a lock nut. Lock nuts are a litde over half the thickness of a standard nut When used in conjunction with a standard nut and tightened, the lock nut is pushed against the thread flanks and locked. Fig. 12.8(a). 

Slotted and castle nuts are used in conjunction with wire or a split pin through a hole in the bolt to prevent the nut from working loose. Fig. 12.8(b). 

Self-locking nuts are available which are easy to assemble and do not require a hole in the bolt or the use of a split pin. One type, known as a Nyloc nut. Fig. 12.8(c), incorporates a nylon insert round the inner top end of the nut. As the nut is screwed on, the nylon yields and forms a thread, creating high friction and resistance to loosening. 

A second type, known as an Aerotight stiff nut. Fig. 12.8(d), has two arms formed on top of the nut These arms, which are threaded, are deflected inwards and downwards. When the nut is screwed on, the arms are forced into their original position and the resistance of these arms gives a good grip on the thread, preventing it from working loose. 

A third type, known as a Philidas self-locking nut. Fig. 13.9(e), has a reduced diameter above the hexagon. Two slots are cut opposite each other in the reduced diameter and the metal above the slots is pushed down, which upsets the thread pitch. When screwed in position, the thread is gripped by the upset portion, preventing the nut from working loose. 

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Gespenstf n. specter, ghost, phantom. Gesperr(e), n. locking device, catch, ratchet, gespieen, p.p. (of speien) spat vomited. Gespinst, n. spun yarn spun goods thread (textile) fabric web cocoon, -faser, /. textile fiber, -pflanze,/. textile plant fiber plant. 

Never place a block valve on the inlet side of a pressure relief device of any kind, unless it conforms to the code practice for rupture disks or locking devices. See [1] Par. UG-135(e) and Appendix M, ASME code. 

STRAP WEBBING PATIENT SECURING BUCKLE W/LOCKING DEVICE SPRING 6530D07S44205 EA 20,01 ... 

After each makeshift locking device was removed from each window, I used a small, thin pry bar to wedge open each window about an eighth of an inch. . . just enough to let outdoor air seep through the window frames to help stir up the dust and keep it dispersed throughout the east end but not open enough so that anyone would notice (that was my intent, anyway). 

As described above, a lockout device can be used as a security measure to prevent unauthorized access to aboveground valves located within chemical processing systems. Valve lockout devices are locks that are specially designed to fit over valves and valve handles to control their ability to be turned or seated. These devices can be used to lock the valve into the desired position. Once the valve is locked, it cannot be turned unless the locking device is unlocked or removed by an authorized individual. 

Teret, S. R, and N. L. Lewin. Policy and Technology for Safer Guns An Annals of Emergency Medicine, vol. 41, 2003, pp. 32-34. Summarizes the current state of safe gun technology. Some handguns now include built-in locking devices. Gun personalization (such as fingerprint readers) have been developed as prototypes but are not yet widely available commercially in firearms. 

A safety door mechanism to prevent opening while the unit is under pressure. The locking device may be actuated directly by internal pressure or indirectly through an automatic switch. The door itself may be the swing-out or sliding type. 

The isolation valve has no locking device. It is always recommended to have a locking device on each isolation valve so it can be blocked in open position. It is also highly recommended that the valve be equipped with a clear position... 

The coupling between barrel and die can be carried out in various ways using bolts or locking devices. They include ... 

The safety pin, held in place by the set-back pin, is the main locking device of the fuze. It holds the slider (which contains the primer and detonator) in its retracted position and prevents premature alinement of the various elements of the powder train. 

Keyless combination locks have been known since the sixteenth century. They contain a series of rings or tumblers threaded on a spindle which must be turned from the outside in such a way that all the rings line up. These rings usually have numbers or letters on them, and if a lock has three rings with 100 numbers on each, there are approximately one million possible combinations, only one of which will open the lock. Combination locks have no keyholes in which to pry or insert explosives, and they became popular for safes and vaults. They are often used in conjunction with time-lock devices, preventing a safe or door from being opened during certain hours even if the correct combination is used. 

Personnel injury This interlock is to prevent injury due to entering the dryer during operation, but more typically to prevent dryer start-up with personnel in the main chamber or inlet or exhaust air ductworK on large dryers. This typically involves microswitches on access doors coupled with proper door lock devices and tags. 

Anaerobic adhesives mainly serve the purpose of protecting threads from undesired loosening as a consequence of vibrations or dynamic stress and represent a preferred alternative to mechanical locking devices. Furthermore, they enable shaft-hub connections, for example, when mounting a gear wheel on a shaft (Figure 11.6). They have also delivered optimal performance as liquidly applied surface seals alternatively to the solid seals required in the respective dimensions. Figure 4.6 shows these application possibilities. 

Anaerobic adhesives for surface sealings and thread-locking devices, furthermore,... 

Capsules manufactured for use on automatic filling machines, which covers almost all pharmaceutical capsules, have locking devices moulded into the side of the capsule (Figure 11.29). There are two locking positions, a pre-lock to prevent premature opening prior to the... 

Figure 2-36. Case 11 Heads attached by mechanical lock devices [1, Section UG-34(m)(n)(o)].

A manual cable -locking device is provided for use during removal of the ONCA from its penetration. When the control rods are completely withdrawn from the core, the cable -locking device is manually actuated to ensure that the control rods will not accidentally drop while the ONCA is moved with the auxiliary service cask. 

A spring returns the plunger to its normal position. A threaded plug is provided in the top of the shock absorber to permit access to the rod locking device. 

After the new fuel assembly has been loaded and the fuel machine removed from the reactor standpipe, closure locking devices are installed, the gag motor drive for channel gas flow adjusted and channel gas outlet thermocouples and gas activity monitoring facilities are connected. Adjustments are then made by the Central Control Room operators to bring the operating conditions for the new fuel assembly to those specified. 

Fig. 4 6 Spectranetics Lead Locking Device stylet in unlocked and locked positions. When the mesh is expanded (locked position), it binds the lead lumen at various points...

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