Coned and threaded connection

Fig. 4.2-2 (right). Coned and - threaded connection (adopted from SITEC). 

For the smaller sizes in nominal pipe diameters with coned -and- threaded connections it is usual to design the pipe-work with standard fittings such as crosses, unions, bulk-head couplings, reducers, adapters, elbows and Tees (for some examples see Fig. 4.2-4). These fittings are normally in cold-worked austenitic steel (e.g., 1.4571 or AISI 316Ti), but features with inserts of other more corrosion-resistant materials are available. 

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