The key of the cleaning automatic tablet counting machine is the control of cleaning processes and parameters with high precision. According to the FDA’s CGMP standard, the concentration of residue should be ≤1μg/cm², and microbial load should be ≤10 CFU/cm². As an example, taking some equipment, wiping the vibrating disk after disassembling with 70% isopropyl alcohol (±2% deviation in concentration) is able to remove the powder residue by 99.8% (detection by HPLC), and the count error reduces from ±3 pieces/thousand pieces to ±0.5 pieces. Turn off the circuit board and let it stand by for 15 minutes (after the temperature drops to 25 ° C ±2 ° C) so that there will be no moisture and short circuit on the circuit board (humidity threshold ≤60%RH).
In the physical cleaning process, a nylon brush (hardness 60D) needs to be used, which will remove mechanical gaps, and a vacuum cleaner (negative pressure ≥15kPa) needs to be used to remove particles with a particle size ≥50μm. Experimental test results show that the sensor false detection rate is increased to 12% when the overall residue is > 0.1g, and if the overall residue is maintained < 0.01g after cleaning, the equipment MTBF is extended from 120 hours to 600 hours. An example of a drug firm reduced its equipment downtime from 2.3 to 0.4 times/month by cleaning three times/day (each for 8 minutes).
Chemical cleaning must be equal to the composition of tablets, water soluble drug residues must be pH 6.5-7.5 neutral detergent (flow rate 1.5L/min), fat soluble residues must be alkaline solution with surfactants (pH 9.0±0.5). Comparative test indicates that by applying 60℃ hot water flushing (flow error ±3%) and rotating nozzle (speed 30rpm), the cleaning efficiency is 58% higher than normal temperature cleaning. A contract manufacturing firm (CMO) used this solution to reduce cleaning verification time from 45 minutes to 18 minutes, saving $24,000 annually in labor.
The disinfection process needs to be applied step by step: first, ultraviolet light (UVC wavelength 275nm, intensity ≥40μW/cm²) is irradiated for 30 minutes to inactivate 99.9% of microorganisms, and then the internal pipeline is atomized with food-grade ethanol (particle size ≤5μm). ATP bioluminescence showed the RLU value (relative light unit) on the device surface decreased from 850 to < 50 after disinfection according to ISO 14698-1. A company has lost $370,000 for skipping this process and batch contamination.
Occasional disassembly is needed in regular deep maintenance, gear group with ultrasonic cleaning machine (40kHz±5%) for 15 minutes with the ability to remove 99.7% of the residue of grease oxidation. The bearing is immersed in petroleum ether with a boiling point of 60-90℃ for 20 minutes, the friction coefficient is reduced to 0.08 from 0.15, and the noise is reduced by 12dB(A). According to statistics from an equipment manufacturer, every quarter deep cleaning is performed, and the lifespan of the transmission system is extended from 2 years to 5 years.
The verification process has to quantify three indicators: no visible residue on visual inspection (white light illuminance ≥500lux), chemical detection (HPLC recovery ≥95%), and microbial detection (contact dish method ≤10 CFU). Based on one laboratory data, the cross-contamination risk declined from 0.07% to 0.002%, and the product recall rate fell by 91%. Maintenance reports show that equipment that performs routine cleaning procedures have a mean yearly maintenance cost of only 23% to those which do not.