Claims
- 1. A method of thermal shock testing a high performance fabricated piping component by subjecting the component to a rapid water temperature rise without nucleation, wherein the method includes use of a hot water generator having a high turndown ratio for rapidly increasing the temperature of hot water to a point of substantially theoretical maximum heat absorption and temperature rise without nucleation, wherein the generator includes a housing defining connected coil and combustor sections, a coil in the coil section with an open central area for receiving combustion gases and defining a water flow path, an inlet and an outlet for said coil, piping connected between the inlet and outlet defining a closed loop water path, a load in the piping, a pump in the piping forcing constant water circulation through the closed loop, a fuel and air induction system including fuel and air controls coacting to deliver the proper mixture of fuel and air to the combustor section, said fuel and air induction system including a fuel line delivering fuel to the combustor section, a combustion air line delivering combustion air to the combustor section, and means continually bleeding air directly into the fuel line to maintain stable combustion in the combustor section at minimum fire conditions, a fast response actuator for said fuel and air controls, and a temperature controller providing operating signals to he actuator in response to a set point temperature and the water temperature of the coil outlet to operate the fuel and air controls and cause a rapid rate of temperature rise in the outlet water temperature without nucleation, said method comprising the steps of mounting said component in said piping connected between the inlet and outlet of the coil, operating said generator between low and high firing rates in a short period of time to produce the maximum heat flux absorbable by the load without incurring nucleate boiling, and observing the function of said component.
- 2. The method of claim 1, wherein the step of operating the generator between low and high firing rates includes monitoring the temperature of the water at the coil outlet to control the increase of firing rate between low and high and prevent nucleation at the coil-water interface.
- 3. The method of claim 1, wherein the step of operating the generator between low and high firing rates includes circulating the water in the closed loop and controlling the flow rate to maintain a pressure related to the water temperature to limit the maximum temperature rise just below the incipient nucleate boiling point of the water.
- 4. A method of thermal shock testing a high performance fabricated piping component by subjecting the component to a rapid water temperature rise without nucleation, wherein the method includes use of a hot water generator having a housing defining connected coil and combustor sections, a coil axially aligned in the coil section with an open central area for receiving combustion gases and defining a water flow path, an inlet and an outlet for said coil, piping outside the generator connected between the inlet and outlet of the coil to define therewith a continuous closed loop water flow path, a load in the piping, a pump in the piping causing a constant water flow in the flow path, a fuel and air induction system including a fuel burner delivering fuel to the combustor section and a blower for producing and delivering combustion air to the combustor section, a fuel line having a fuel metering valve therein and connected to the burner to deliver fuel thereto, a duct connecting the blower to the combustor section and having means therein for controlling the amount of combustion air to the combustor section, and means for maintaining stable combustion in the combustor section at minimum air-fuel openings comprising a combustion air bleed line ahead of the combustion air controlling means for continually bleeding a small amount of air directly into the fuel line downstream of the fuel metering valve, said method comprising the steps of mounting said component in said piping connected between the inlet and outlet of the coil, operating said generator between low and high firing rates in a short period of time to produce the maximum heat flux absorbable by the load without incurring nucleate boiling, and observing the function of said component.
Parent Case Info
This is a division of application Ser. No. 437,249, filed Jan. 28, 1974, now U.S. Pat. No. 3,890,936, dated June 24, 1975.
US Referenced Citations (7)
Divisions (1)
|
Number |
Date |
Country |
Parent |
437249 |
Jan 1974 |
|