Thermostatic control system

摘要

A system for controlling the amount of natural supply gas delivered from a natural gas supply source to a natural gas burner adapted to continually heat a process fluid in a vessel and for enabling the gas burner to continuously automatically maintain the temperature of the process fluid within a predetermined minimum range of temperatures above and below a preset nominal temperature. The system comprises a gas operated flow regulator device associated with a supply gas line connected to the gas burner for regulating the amount of gas delivered to the gas burner in accordance with pressure of regulator control gas delivered to the flow regulator device through a control gas line, gas pressure control apparatus associated with the control gas line for varying the pressure of the control gas delivered to the flow regulator device; and a linearly movable temperature sensing device operable by process fluid temperature and connected to the gas pressure control apparatus to vary the control gas pressure.