A steam & mining industry manufactures globe valves and angle valves designed and constructed to enable the disc to operate vertically to the seat. These have the most basic construction for complete closure against the fluid flow. These types of valves are suited to shut-off or flow control, since the flow direction is steeply changed in the valve, which causes a remarkable flow resistance. Both y-pattern and angle valves are kind of globe valves: the former eliminates steepness of flow change and the latter changes the flow direction at 90 ΓΈ . The following disc shapes are produced according to the required service: plug, flat, ball, and bevel type discs for lower pressure service, ring joint type for normal pressure, and pressure seal or welded bonnet type for higher pressure. These are mainly o, s and y type with stems either rotating or non-rotating type. Special hard facing is provided on the stem to prevent it from seizing and scoring. Seats are precisely machined and lapped to prevent leakage, and are designed for either screwed, welded or integral type. The valves, installed for higher temperature service, are of a flexible design to prevent breakage due to expansion by heat.
