Ferrules, coupling

Hoses must be made for anhydrous ammonia service 2500 kPa (348 psig) working pressure and stamped for this service. In locations where hoses may be abraded, wke braid armored or reinforced hose types should be used. Hose ends should have boss or other acceptable ak kon ferruled couplings. 

The photograph shows various nut-ferrule assemblies that have been set into the same-make union. Note the difference in the length and pitch of the nut threads (this makes nuts from one manufacturer incompatible with others). Also note the distance that the tubing extends from the ferrule is different. Obviously, a nut-ferrule couple fourth from the top will not seal well in a union design for a nut-ferrule set shown second from the top (different tubing set distances, different ferrule lengths, and different threading of the nut). 

Fig. 2.16. Schematic of the coupling of the nanocolumn to the injection valve [44], 1, nano-column (75 pm I.D. x 360 pm O.D.) 2, knurled nut and ferrules 3, fused-silica make-up adapter (split device 504 pm I.D.) 4, micro-injection valve (column port 250 pm i.d.) 5, rotor 6, outlet port of the make-up adapter.

Figure 2.2 Cross-sectional diagram of the components used to couple two pieces of stainless steel tubing. Top Units before swaging. T, tubing to be joined B, male bolt F, female N, female nut. Bottom After swaging. The pressure of the bolt on the nut has forced the ferrule to seal the joint between the two ends of the tubing.

Figure 2.2 Microfabricated device and the coupling system to an ESI-MS-MS mass spectrometer. A, transfer capillary (15 cm) B, guide capillary (200 pm i.d. x 360 pm o.d.) C, Teflon tubing D, finger-tight fitting and ferrule E, mount—top plate F, mount—bottom plate G, pFAB device H, main channel exit I, silicone gasket J, liquid-junction ESI interface. The inset shows the union of the device and a 350 pm o.d. and 50 pm i.d. capillary tubing at the end of the main channel. (Adapted with permission from Ref. 13).

A) Conventional HPLC column terminator for 1/16" fittings a) Capillary b) Nut c) Ferrule d) End fitting with internal thread e) Coupling body to column 0 Metal frit g) Filter paper h) Sealing ring i) Stainless steel tubing j) Column... 

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