Limiting Orifice Valve for Nozzle-Mix Burners

Therm process Engineering Pvt. Ltd. manufactures a specially designed limiting orifice valve for setting gas or air flow at nozzle-mix burners. On a multi-burner furnace, each burner should receive the same, correct flow. The limiting orifice valve lets the commissioning engineer set that flow precisely, burner by burner, using a screwdriver. Turning counter-clockwise increases flow and turning clockwise reduces it. Therm process uses these valves on its own furnaces, including solution annealing furnaces, where each burner is calibrated for steady gas flow.

What Is a Limiting Orifice Valve?

A limiting orifice valve is an adjustable flow-limiting device installed in the gas or air line to an individual burner. It sets the maximum flow that burner can receive.

In a nozzle-mix burner, gas and air are kept separate until they mix at the burner nozzle. For stable combustion and the right flame, each burner needs the correct gas and air flow. On a furnace with many burners on a common manifold, burners nearer the supply can take more than their share, while distant burners are starved. That leads to uneven heating.

Installing a limiting orifice valve on each burner lets the flow be set and balanced individually. Once set, the valve limits flow to the calibrated value, helping every burner fire as intended.

Therm process Limiting Orifice Valve

• Purpose. Set the desired gas or air flow at a nozzle-mix burner.
• Adjustment. Precise setting with a screwdriver.

- Counter - clockwise - increases flow
- Clockwise - decreases flow

• Design. Specially designed by Therm process for its burner systems.
• Proven use. Used on Therm process solution annealing furnaces to set and calibrate each burner for steady gas flow.

Technical Specifications

Key Features

• Precise flow setting at each burner.
• Simple screwdriver adjustment.
• Gas or air service.
• Designed by a burner manufacturer.
• Field-proven on Therm process furnace

Applications

• Multi-burner heat treatment furnaces, such as solution annealing.
• Reheating and forging furnaces with nozzle-mix burners.
• Burner commissioning and balancing.
• Retrofits to improve temperature uniformity.

Benefits

• Balanced burners, leading to more uniform furnace temperature.
• Steady gas flow per burner.
• Easier commissioning and re-tuning.
• Reduced fuel waste from over-firing burners.

Related Therm process Products

• Industrial Burners
• Solution Annealing Furnace
• Combustion Blower
• Accessories

Frequently Asked Questions