8481.80.90.15 - Regulator valves, self-operating, for controlling variables such as temperature, pressure, flow and liquid level

This classification covers self-operating regulator valves designed to automatically control specific process variables. These valves are engineered to adjust their internal mechanism based on changes in temperature, pressure, flow rate, or liquid level, without external manipulation. Examples include self-actuating pressure-reducing valves that maintain a constant downstream pressure, or thermostatic valves that regulate temperature by controlling fluid flow.

Unlike sibling categories such as solenoid valves, which are electrically operated, or ballcock mechanisms primarily used for toilet tank water level control, this category focuses on valves that are intrinsically driven by the process variable they are intended to regulate. The mechanism of operation is key; these are typically diaphragm, bellows, or spring-loaded valves that respond directly to the physical conditions they monitor.

As this represents a leaf node within the HTS, there are no further subdivisions. The classification for these self-operating regulator valves is final at this level. Therefore, proper classification hinges on confirming that the valve in question is indeed self-actuating and its primary function is to regulate variables like temperature, pressure, flow, or liquid level in a continuous, automatic manner.