Yingtai: Selection and Maintenance of Vacuum Pumps for Freeze Dryers

Yingtai: Selection and Maintenance of Vacuum Pumps for Freeze Dryers  

Freeze dryers are widely used in biopharmaceuticals, food processing, chemical engineering, and other fields. The vacuum pump serves as the "power core" of a freeze dryer, enabling lyophilization by creating a low-pressure environment and removing gases and water vapor. Its performance and maintenance directly impact drying efficiency, product quality, and energy consumption, as well as the stability of the freeze-drying process and the final product's characteristics (e.g., preservation of porous structure, survival rate of active ingredients).  

Factors to Consider When Selecting a Vacuum Pump  

01 Vacuum Requirements  

Different freeze-drying processes have varying vacuum requirements (especially for pilot-scale R&D freeze dryers), so the appropriate vacuum pump must be selected based on specific process needs.  

02 Pumping Speed  

Pumping speed refers to the volume of gas a vacuum pump can extract per unit of time. The selection should match the size of the freeze-drying chamber and the quantity of samples.  

03 Operational Stability  

Since freeze-drying requires prolonged operation, a vacuum pump with high stability and low failure rates is essential.  

04 Maintenance Costs  

Different types of vacuum pumps have varying maintenance costs. The right pump should be chosen based on practical considerations to minimize upkeep expenses.  

Maintenance & Care  

To ensure normal operation and extend the service life of the freeze dryer's vacuum pump, regular maintenance is essential.  

Reminders:  

① Always disconnect the power supply before inspection, and do not turn it on during the process to avoid injury.  

② After stopping the pump, wait until it has completely cooled down before inspection to prevent burns.  

01 Checking Pump Oil  

To maintain pump performance and longevity, ensure the oil is clean and at the proper level. The oil change interval varies depending on operating conditions and must be checked regularly.  

1.1 Oil Level Inspection  

During operation, the oil level should always remain between the MAX and MIN marks on the gauge. If it falls below MIN, refill promptly. If it exceeds MAX, drain the excess oil by loosening the drain plug.  

1.2 Quality Inspection

Observe the oil color—normal pump oil should be clear and transparent. If the oil appears dark or cloudy, replace it immediately.  

02 Oil Change  

2.1 If the pump ingests large amounts of water, organic solvents, or corrosive gases, change the oil immediately.  

2.2 If the vacuum level continuously declines during operation, replace the oil promptly.  

2.3 For new pumps, the first oil change is recommended after 100 hours of operation.  

2.4 If the pump operates under high pressure (>10,000 Pa) for extended periods, oil consumption increases—monitor and replenish as needed.  

2.5 For low-pressure extraction of clean gases, replace the oil approximately every 2,000 hours.  

03 Regular Inspection  

Additionally, routinely check all pump components for looseness or damage, and tighten or replace them as necessary.