Refrigerant Filling in Automotive Manufacturing: Process Overview
Introduction
Refrigerant filling in automotive manufacturing is a critical process in vehicle assembly, directly affecting the performance, safety, and longevity of air conditioning and thermal management systems. Unlike simple gravity filling, modern production lines demand a controlled, repeatable method that removes air and moisture, verifies system integrity, and delivers an exact refrigerant or coolant charge under stable conditions.
This process overview examines the vacuum filling method used for coolant and antifreeze, explaining how vacuum evacuation, leak testing, pressure filling, and back suction work together to achieve a precise liquid level. It also outlines the equipment characteristics that support automated filling on automotive production and assembly lines.
Product Overview
The Antifreeze Vacuum Filling Machine is a PLC-controlled system designed for automated coolant and antifreeze filling. It integrates vacuum evacuation, leak testing under vacuum and pressure conditions, pressure filling, and back suction into a single cycle. The machine is suitable for automotive production and assembly lines where consistent liquid levels and system tightness are required.
The equipment handles a filling volume of 1–400 L with a filling pressure of 1–4 bar and a maximum filling speed of 60 L/min. Filling precision is ±0.5%, and liquid level accuracy is ±2 mm. The vacuum pump capacity ranges from 40 to 65 m³/h. Negative pressure leak rate is ≤0.5 mbar / 60 s, and positive pressure leakage is <1.4 g/year. The machine operates on AC 380 V ±10%, 50 Hz ±2% and has dimensions of 1800 × 1000 × 800 mm (customizable).
Working Principle
The filling cycle follows a defined sequence controlled by the PLC system:
Vacuum evacuation: The system first creates a vacuum to remove air and moisture from the circuit.
Leak testing: Under vacuum and pressure conditions, the system checks for leaks to confirm circuit tightness.
Secondary vacuum: After tightness is confirmed, a secondary vacuum is created before coolant introduction.
Pressure filling: Coolant is introduced under controlled pressure.
Pressure equilibrium: Once filling pressure reaches equilibrium, the system automatically vents to atmospheric pressure.
Back suction: Excess coolant is removed to achieve the specified liquid level and prevent the coolant level from dropping after filling.
This integrated cycle supports precise filling with a stable liquid level, reducing the risk of incomplete filling or overfilling.
Key Features
PLC-controlled automation of the complete coolant filling process
Integrated vacuum evacuation, leak testing, pressure filling, and back suction
Filling volume range: 1–400 L
Filling pressure range: 1–4 bar
Maximum filling speed: 60 L/min
Filling precision: ±0.5%
Liquid level accuracy: ±2 mm
Measurement display range: 0.0–999.9 L
Vacuum pump capacity: 40–65 m³/h
Negative pressure leak rate: ≤0.5 mbar / 60 s
Positive pressure leakage: <1.4 g/year
Power supply: AC 380 V ±10%, 50 Hz ±2%
Dimensions: 1800 × 1000 × 800 mm (customizable)
Applications
The Antifreeze Vacuum Filling Machine is designed for automated coolant and antifreeze filling applications on automotive production and assembly lines. It supports precise filling with a stable liquid level, making it suitable for manufacturing environments where repeatability and leak-free operation are important.
Typical applications include filling of coolant circuits in vehicle assembly, where the machine's integrated leak testing and back suction help ensure the specified liquid level is achieved and maintained. The equipment can be integrated into production lines that require controlled filling volumes and pressures.
Benefits
Improved traceability: PLC control and measurement display support consistent process monitoring.
Better process consistency: Automated cycle reduces variability in filling volume and liquid level.
Production integration: Suitable for automotive production and assembly lines.
Quality management: Integrated leak testing helps verify system tightness before filling.
Stable liquid level: Back suction prevents the coolant level from dropping after filling.
Why Choose
KINMARK, through its Jinan Zhongzheng Jinma Technology Co., Ltd. entity, has been engaged in automotive intelligent automation equipment since 1996. The company develops and manufactures marking and traceability systems, fluid filling systems, servo press systems, and robot automation systems. Its fluid filling solutions are used in automotive manufacturing and related industries.
The Antifreeze Vacuum Filling Machine reflects this focus by combining vacuum evacuation, leak testing, pressure filling, and back suction in a PLC-controlled system. KINMARK provides a 12-month warranty, fast response service with remote diagnosis, and installation and commissioning support with operator training.
Frequently Asked Questions
What is refrigerant filling in automotive manufacturing?
Refrigerant filling in automotive manufacturing refers to the controlled process of charging a vehicle's air conditioning or thermal management system with refrigerant or coolant. In modern production, this is often done using vacuum filling equipment that evacuates air and moisture, tests for leaks, and fills under pressure to achieve a precise liquid level.
How does a vacuum filling machine achieve a stable liquid level?
After pressure filling reaches equilibrium, the system automatically vents to atmospheric pressure and performs back suction to remove excess coolant. This back suction step helps achieve the specified liquid level and prevents the coolant level from dropping after filling.
What is the purpose of leak testing in the filling cycle?
Leak testing under vacuum and pressure conditions confirms system tightness before coolant is introduced. The machine's negative pressure leak rate is ≤0.5 mbar / 60 s, and positive pressure leakage is <1.4 g/year, supporting verification of circuit integrity.
What filling volumes and pressures does the machine support?
The Antifreeze Vacuum Filling Machine supports a filling volume of 1–400 L and a filling pressure of 1–4 bar. Maximum filling speed is 60 L/min, with filling precision of ±0.5% and liquid level accuracy of ±2 mm.
Can the machine be integrated into an existing assembly line?
Yes. The machine is designed for automated coolant and antifreeze filling applications on automotive production and assembly lines. Its PLC-controlled cycle integrates vacuum evacuation, leak testing, pressure filling, and back suction, and equipment dimensions are customizable.
Conclusion
Refrigerant filling in automotive manufacturing requires more than delivering fluid to a system. It demands controlled vacuum evacuation, reliable leak testing, precise pressure filling, and back suction to achieve a stable liquid level. The Antifreeze Vacuum Filling Machine addresses these requirements with a PLC-controlled cycle and defined technical specifications, supporting automated filling on production and assembly lines.
If you're interested in any of the equipment mentioned in this article, feel free to contact our sales engineers for detailed product information and customized technical solutions.