The needle valve block models

A valve with a needlelike part, a fine adjustment, or a small opening, especially a valve in which the opening is controlled by a needlelike or conical point that fits into a conical seat.  The needle valve block models a variable orifice created by a conical needle and a round sharp-edged orifice in thin material.
Needle valves within a block and bleed function help achieve positive isolation within maintenance operations of a live process plant. These work well in non-critical processes like with non-hazardous fluids or a low pressure system. The small port and needle-shaped, threaded plunger allows for precise flow regulation in low flow applications. Not only for maintenance, needle valves also work well in flow-metering operations, and are especially good at maintaining a calibrated and constant low flow rate.