Orifice Expansion Valves

An Orifice Expansion Valve, also known as a fixed orifice tube, is a crucial component in refrigeration and air conditioning (HVAC) systems. It controls the amount of refrigerant entering the evaporator by creating a pressure drop, allowing the refrigerant to expand and cool efficiently. Unlike thermostatic expansion valves (TXV), the orifice valve has a fixed opening size, meaning it does not adjust dynamically to temperature changes.

Orifice expansion valves are widely used in automotive air conditioning, split AC systems, and refrigeration units where a simple, cost-effective, and reliable flow control solution is required. They are typically installed between the condenser and evaporator to regulate refrigerant flow based on system pressure.

Features of Orifice Expansion Valve:

✅ Fixed Orifice Design – Simple and reliable with no moving parts.
✅ Efficient Refrigerant Control – Ensures proper flow rate for optimal cooling.
✅ Cost-Effective – Less expensive than adjustable expansion valves.
✅ Compact & Lightweight – Small size makes it easy to install in HVAC systems.
✅ Low Maintenance – No adjustments required after installation.
✅ Durable Construction – Made from brass, aluminum, or stainless steel for longevity.

Specifications:

• Material: Brass, Aluminum, or Stainless Steel
• Orifice Size: Fixed (varies based on system requirements)
• Operating Pressure: Typically 100-300 PSI (depends on refrigerant type)
• Temperature Range: -40°C to +80°C
• Refrigerant Compatibility: R-134a, R-410A, R-22, R-404A, etc.
• Application: Automotive AC, Refrigeration Units, HVAC Systems

An Orifice Expansion Valve is a crucial flow control component in refrigeration and air conditioning (HVAC) systems. It is designed to meter and regulate the amount of refrigerant that flows from the high-pressure condenser side into the low-pressure evaporator side, allowing the refrigerant to expand and cool efficiently.

Unlike Thermostatic Expansion Valves (TXV), which adjust dynamically based on temperature and pressure, an orifice expansion valve has a fixed-size orifice that provides constant flow restriction. This makes it simpler, more reliable, and cost-effective, but it does not adapt to varying cooling loads.

1. Working Principle of Orifice Expansion Valve

The orifice valve operates based on pressure differential between the condenser and evaporator:

1. High-pressure liquid refrigerant enters the valve from the condenser.
2. The fixed orifice restricts flow, causing a pressure drop.
3. The refrigerant expands as it enters the low-pressure evaporator, cooling down rapidly.
4. The low-pressure, low-temperature refrigerant absorbs heat from the surroundings, enabling the cooling process.