10 Jun What is ultrasonic cleaning?
Current Industrial Cleaning Scenario
Cleaning technology for industrial machinery and equipment is dynamic. The usage of vapour degreasing using harsh chemicals is reducing due to increased awareness of the harmful impact on the environment. Simultaneously, demand for superior cleaning methods is increasing. Cleanliness has come across as an important issue in many industries as India evolves into a global manufacturing hub.
One of the significant innovations in industrial cleaning is the usage of ultrasonic technology. Ultrasonic cleaning is an aqueous-based eco-friendly cleaning technique. It is now used extensively to boost the speed of operations and enhance the cleaning.
What is Ultrasonics?
Ultrasonics are high-frequency sound waves above the upper limit of the human audible range i.e. frequencies above 20 kHz.
How does ultrasonic cleaning work?
- Ultrasonic cleaning works on the principle of cavitation. Cavitation effect is produced when ultrasonic sound waves are introduced into a cleaning liquid by means of a transducer mounted on or immersed in a cleaning tank.
- The sound creates compression and expansion waves at high frequencies in the liquid.
- In the expansion wave, small vacuum cavities are formed. These cavities collapse, or implode, during the compression wave as molecules of the liquid are tightly compressed.
- This continuous rapid process of imploding vacuum bubbles on the substrate to be cleaned is responsible for the scrubbing effect which produces ultrasonic cleaning.
Factors to be considered for Ultrasonic Cleaning:
- Time: Conventional or manual cleaning methods require more time compared to ultrasonic cleaning. Ultrasonic cleaning takes minutes to clean batches of components or entire assemblies. This reduces downtime and helps in faster maintenance or production.
- Temperature & Chemistry: These are two major factors affecting ultrasonic cleaning. For effective cleaning, depending upon the chemical used, the temperature requirement varies.
- Proximity to the transducer/part fixture design: In ultrasonic cleaning, transducers are used to produce the ultrasonic effect. These ultrasonic transducers are mounted according to the design of the system. Transducers can be mounted at the bottom or on the sides of the systems. They can also be immersed in the system.
- Ultrasonic output frequency: The most common frequency used for ultrasonic cleaning is 35 kHz to 40 kHz. For sensitive and delicate cleaning applications, high frequencies are suitable as cavitation bubbles can easily penetrate small holes and crevices. For bigger parts, lower frequencies of 20-25 kHz are used. These have a tendency to clean more aggressively as the bubbles produced are larger.
- Ultrasonic Power: Ultrasonic cleaning consumes electrical power evenly. However, it releases it in intervals to produce the ultrasonic waves in the liquid. The requirement of the cleaning power depends upon the application. More power usually indicates faster and more effective cleaning. However, too much power can damage delicate parts like electronic circuits, soft metals, etc. Larger the volume of the cleaning solution, the larger the power requirement.
- Tanks: Generally, ultrasonic cleaning systems have two tanks. One is a cleaning tank and the other is a reservoir tank. The size and the shape of the cleaning tank depends on the application, the size of the object, and the number of objects to be cleaned at a time. The reservoir tank maintains the liquid level in the cleaning tank by recirculating fluid into the cleaning tank after filtering it.
- Cleaning basket: For ultrasonic cleaning, the objects to be cleaned need to be immersed inside the liquid. Baskets are used for this purpose. You can put separate parts or entire assemblies into the basket based on the specification. The size of the basket varies from equipment to equipment based on the requirement. These baskets hold the objects into the cleaning liquids. Hence, handling the objects becomes easier.
Why Ultrasonic Cleaning?
- Intricate shapes: Ultrasonic cleaning is an immersion cleaning method. As long as the cleaning solution is in contact with the surface of the object, cleaning will take place. Most automotive parts like engines have hard-to-reach grooves or intricate shapes where dirt and unwanted oils and particles settle. These can damage the engine. Ultrasonic cleaning is the only cleaning method that can clean inside hidden holes and crevices as well as the exposed surfaces.
- Labour Work: Since an automated cleaning system is introduced in the manufacturing line it reduces dependence on unskilled labourers.
- Time: Since many components can be cleaned at a time automatically, it reduces overall maintenance time and simultaneously increases productivity.
- Environment & Labour Safety: Since ultrasonic cleaning is primarily an aqueous-based cleaning technique it uses water-based detergents rather than toxic chemicals. This reduces the exposure of labourers and the environment to toxic chemicals.
- Quality: Ultrasonic cleaning cleans surfaces without any scrubbing, abrasion or pressure sprays. This ensures high-quality cleaning for delicate parts.
- Versatile & Flexible: These machines can clean each and every type of contaminant like dust, dirt, oils, waxes, clay, sand, carbon deposits, corrosion etc. This ensures an unparalleled level of flexibility in cleaning.
- Easy Maintenance: Ultrasonic cleaning machines are maintenance-free. This ensures very low downtimes.
- Efficiency: Ultrasonic cleaning is the most efficient cleaning method. Cleaning takes place with minimal usage of water compared to spray cleaning. Being an automatic cleaning technique, a lot of labour time is also saved.
Applications for ultrasonic cleaning
- Aircraft components, brakes, machined parts
- Cleaning of ceramic, glass, metals
- Automotive fuel injector nozzles and components
- Blind cleaning
- Carbide cutting tools
- TV picture tube components
- Computer disk drive and head components
- Glassware cleaning (laboratory glassware)
- Microelectronic circuits (thin and thick film circuits)
- Jewelry cleaning
- Lenses, ophthalmics
- Maintenance/cleaning of electronic assemblies
- Maintenance/cleaning mechanical assemblies
- Maintenance/cleaning of food manufacturing filling equipment
- Medical glassware
- Cleaning of molds
- Optical components
- Orthopedic implants
- Pre-cleaning of metals for further manufacturing processes
- Motherboards and circuit cleaning of electronics types of equipment like Radio, TV, Computer, Mobile phones
- Semiconductor components, substrates, and sub-assemblies
- Surgical instruments
- Manufacturing & maintenance of ammunition
- Wire drawing cleaning
Ralsonics Ultrasonic Cleaning Technology
In industrial setups, objects to be cleaned have a clearly defined process and cleaning requirement. As a result, the available cleaning time in a production/maintenance assembly line is well-defined. Furthermore, it is not necessarily possible to disrupt an assembly line. In such cases, Ralsonics can provide solutions to add ultrasonics to existing assembly lines. A cleaning station can easily be added without changing the available production processes. We can also provide custom automation options that can allow you to modify your cleaning setup so that manpower gets engaged in other tasks instead of moving parts or monitoring a cleaning process.
In a fast-paced working environment where quality expectations and repair costs are sky-high, ultrasonic cleaning surpasses all expectations. If you still have any doubts on whether this technology fits your requirement for items you clean, you are just a click away. Ralsonics, Happy to help you..