Threaded components

C = sum of allowances for corrosion, erosion, and any thread or groove depth. For threaded components the depth is h of ANSI B2.1, and for grooved components the depth is the depth removed (plus Vc,4 in when no tolerance is specified). 

BS 2816 Electroplated Coatings of Silver for Engineering Purposes BS 3382 Electroplated Coatings on Threaded Components ... 

Thicker Platings for Threaded Components BS 3597 Electroplated Coatings of 65/35 Tin-nickel Alloy... 

Threaded components and small articles on which excess zinc would interfere with their intended use, or which would otherwise stick together, are galvanised in perforated baskets which are transferred to a centrifuge and spun. This procedure for galvanising small parts is sometimes referred to as spin galvanising . 

British standards General work BS 729 Continuous galvanised plain sheet BS 2989 Corrugated sheet BS 3083 Wire BS 443 Tubes BS 1387 BS 2S69 Part 1 BS 1706 Threaded components BS 3382 BS 4921 BS 46S2 for the paint... 

Process Process, thread, component Synchronization relations precedes, excludes, controls assignment of software components to processes and threads... 

Scheme 19 Stoddart has employed the clipping method to prepare [2]rotaxane 42. Reversible imine bonds are used to generate a dynamic mixture containing the threaded and un-threaded components...

The light-driven dethreading of a pseudorotaxane whose thread component is immobilized on the surface of a silica sol-gel film was investigated.94 A molecular triad for photoinduced charge separation was attached to a gold electrode and used to drive the dethreading of a pseudorotaxane in a photoelectrochemical setup.95... 

Threaded species, in which the threaded component is covalently bound to the macrocycle, could also be obtained, in principle, by clipping, that is by cyclization around the thread of a precursor to the macrocycle covalently attached to it. Schill and Tafelmair [42] tried to prepare a rotaxane by intramolecular cyclization of diamine (50) (Figure 21). Unfortunately, only the undesired, extraannular compound... 

In both cases, a distinction must be made between the many variants of lap joints on the one hand and co-axial assemblies in general on the other. Threaded components must be singled out, for, when bonded, they do not behave as slip-fitted unthreaded parts. They are therefore dealt with separately in Sections 2.3.1 and 2.3.2. 

Threaded components (excluding smooth co-axial assemblies)... 

Anaerobic compositions suppress inter-component thread corrosion very effectively by preventing the free passage of oxygen and water-both essential for the process of corrosion. Thus, in bad environments such as coal mines, they are frequently used to make maintenance possible simply by preventing formation of corrosion products which might otherwise irretrievably lock threaded components. 

Plate 10 a Prior to fitting the piston head (Plate 11b) to the threaded end of the piston rod, the thread is treated with an extremely strong anaerobic adhesive to ensure that the assembly torque is maintained and that the piston is held firmly in position. The larger threaded component (left centre) is the ram cylinder end cap (see Plate 11b). Material Permabond APP460. (Photograph courtesy JCB Ltd.)... 

Medium-strength adhesives have now been proven to out-perform all normal mechanical means of retaining threaded components while still allowing simple removal of the fasteners for maintenance. 

The soft and ductile cadmium metal has low friction. Threaded components, such as screws, were cadmium-plated in order to avoid locking. For this use zinc is not suitable, but tin has proved to be a good alternative. 

The steel part to be bonded is baked whilst being tumbled in zinc dust. The process is not generally suitable for delicate metal parts and causes problems with zinc build-up in screw threaded components (the latter must be protected by a sleeve or require a die running down the thread to clear it). After treatment exposed zinc surfaces do of course oxidise if stored incorrectly, but this is not usually a problem. The oxide forms after both methods of zinc coating. 

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