Vol. 11
May Issue
Year 2010

Cover Page

in Vol. 11 - May Issue - Year 2010
Weber Ultrasonics – components for efficient parts cleanness Gentle, Cost-Effective Cleaning With Ultrasonic Technology

Using ultrasonic components tailored to suit requirements, Weber Ultrasonics makes it possible to build effective and economic ultrasonic cleaning units for all cleaning tasks

The SONOPUSH MONO HD rod-style transducers offer 20 percent more output at the same beam length, resulting in significantly shorter cleaning times that translate into higher throughput at lower costs

(left: conventionally welded ultrasonic housing, right: laser-welded SONOSUB) The very smooth, delicate laser-welded seam of the SONOSUB submersible transducer (right) prevents dirt particles from building up at the joint

The innovative 1-MHz ultrasonic module generator ULTRASONIC MICRO CLEANING (UMC) was developed for cleaning highly sensitive surfaces and fine structures. The use of innovative high-tech components enables up to six modules to be integrated in a 19" housing.

Component cleanness has become a quality criterion, requiring ever tougher standards to be met. This means that efficient cleaning processes are called for, such as ultrasonic cleaning. Innovative ultrasonic components from Weber Ultrasonics make it possible to achieve excellent levels of cleanness within a short time, even for geometrically complicated workpieces and complex assemblies. And what’s more, the cleaning is gentle on materials and uses minimal amounts of chemicals and energy.

Regardless of whether workpieces are produced using shaping, swarf-producing or casting processes, any further processing or assembly will usually involve the removal of residue such as swarf, dust, oils, emulsions and release agents, whereby defined levels of cleanness often need to be met. Ultrasonic cleaning is the optimal procedure in these cases, as it enables both particulate soiling and films to be removed from workpieces efficiently, reliably and gently. The cleaning effect is based on the physical principle of cavitation: an ultrasonic generator emits electrical signals at a certain frequency, which are then transferred to the liquid as waves of ultrasound via a rod-style or plate transducer. The sonic pressure is characterised by the interplay of underpressure and overpressure. As a result of the high intensity, microscopic bubbles form in the underpressure phases, which then implode in the subsequent overpressure phase, releasing shock waves with considerable energy densities. This also triggers microflows in the liquid, which separate and clean away films and particulate matter from the components to be cleaned, even for workpieces with complex geometry, such as indentations, blind holes, cracks and hollows.

The Ultrasonic Frequency – A Key Factor in Component Cleanness

When it comes to ultrasonic cleaning, the rule of thumb is: the lower the frequency, the higher the energy released by the ultrasonic waves. If the frequency is too low, this can damage sensitive cleaning objects, while an excessive frequency leads to a substandard cleaning result. The reference values when selecting the ultrasonic frequency are:
• 25 - 40 kHz: For cleaning particles, grease and oils from hard, unpolished surfaces
• 50 - 80 kHz: For fine cleaning, cleaning polished surfaces
• 120 kHz and above: Superfine cleaning and cleaning of highly polished surfaces
• above 500 kHz: Non-destructive cleaning of extremely fine structures, for example in micro and nanotechnology, the semiconductor industry and photovoltaics

Components for Ultrasonic Cleaning to Suit Your Needs

Weber Ultrasonics, one of the world’s leading manufacturers of ultrasonic components and joint creator of the push-pull principle, offers solutions that are optimally designed for different requirements. These solutions include the SONIC DIGITAL digital ultrasonic generators with frequencies of 25 to 250 kHz with the accompanying SONOPUSH, SONOPLATE and SONOSUB transducer systems.
Thanks to their digital frequency generation and control, the ultrasonic generators from the Ittersbach-based company provide an extremely high consistency of frequency, amplitude and output, enabling a high-quality cleaning process with reproducible results. All process-relevant parameters, such as power output, temperature and time can be controlled and monitored using an interface. Plus, the generators are equipped with various innovative protective functions for a high degree of operational and process safety.
Where different cleaning tasks such as precleaning and fine cleaning require ultrasonic waves of different frequencies, Weber Ultrasonics offers an efficient solution in the form of the SONIC DIGITAL MULTI modular ultrasonic generators and the SONOSUB MULTI submersible transducer. Unlike conventional ultrasonic generators, which can usually only generate one frequency, these devices can produce up to three frequencies (40, 80 and 120 kHz and 25 and 50 kHz).

For cleaning sensitive components and fine structures, as are common in the optical and semiconductor industry, electronics, precision mechanics, microtechnology and photovoltaics, Weber Ultrasonics has added the 250 kHz module generator to its tried and tested SONIC DIGITAL series of digital ultrasonic generators. The new 19" device is available with a power output of 250 and 500 Watt. Like all ultrasonic generators from Weber Ultrasonics, the power output can be set steplessly between 10% and 100% via power control. The SONIC DIGITAL 250’s high efficiency, compact design, convenient operation and sophisticated features for maximum process and operational safety give it the edge over the competition.
The comprehensive range of generator products enables you to build economic ultrasonic cleaning units which are tailored to suit requirements and offer a high level of process safety for virtually all cleaning tasks.

Transducer Systems that Set New Standards

The systems from Weber Ultrasonics also set the standard when it comes to transducers for transferring the ultrasonic waves into the fluid. When you need to meet strict demands under the toughest conditions, the SONOPUSH MONO HD rod-style transducer really comes into its own. Unlike conventional rod-style transducers, it produces 20% more power output at the same beam length and consistent omnidirectional sonic distribution. The heavy duty rod-style transducer therefore offers considerable advantages in all cleaning applications, which is evident in shorter cleaning times, resulting in a higher throughput and thus lower costs. What’s more, a high level of stability, resistance to temperatures of up to 95°C even in continuous operation and vacuum and overpressure resistance up to 10 bar ensure a long service life. The low space requirement of the SONOPUSH MONO HD means it can be added to existing cleaning units and tanks with the greatest of ease.
Weber Ultrasonics is also a pioneer in employing the latest manufacturing procedures for ultrasonic components. In order to prevent transducer elements re-contaminating or soiling the cleaning and rinsing tanks, the housing of the SONOSUB submersible transducer is laser-welded. This innovative welding technique means the ultrasonic transducer housing can be manufactured with a dimensional accuracy and lack of distortion not possible with any other welding method. Moreover, the automated, reproducible robotic welding process also lends the welded joints a significantly higher quality and strength. Another bonus of the laser welding process is the extremely smooth, delicate and almost invisible welded joints. In contrast to housings welded using conventional means, the risk of fine dirt deposits at the joints is utterly insignificant. This prevents process-related soiling resulting in recontamination of the parts to be cleaned or in contamination of the cleaning and/or rinsing tanks.

Megasonic for the Toughest Cleanness, Component Care and Efficiency Requirements

With its innovative 1 MHz and 500 kHz ULTRASONIC MICRO CLEANING (UMC) module generators, Weber Ultrasonics has created the ideal conditions for efficient and reproducible cleanliness in micro and nanotechnical production. Photovoltaics, semiconductor technology, precision and micro optics, medical technology, the LIGA process, microsystems and nanotechnology – wherever highly sensitive surfaces and finely structured components are to be cleaned, the new UMC module generators and matching transducer systems show their superiority. Even the finest nano-scaled particles and film contamination is removed from surfaces and from troughs within microstructures without causing damage or leaving any residue. With power outputs of 250 or 500 Watt, the UMC generators are able to optimally adapt to individual cleaning requirements. At the same time, innovative high-tech components make it possible to achieve maximum performance while requiring a minimum of space: up to six 1 MHz modules can be integrated in one 19" housing. As a result, a single housing can hold a cleaning system with a total power output of up to 3000 Watt, thereby saving in production area.
The new UMC generators boast maximum stability of all process-relevant parameters thanks to the latest control technology. This in turn leads to optimum coordination between generators and accompanying transducers, ensuring a transmission of energy with virtually no loss. The resulting high degree of efficiency of the UMC cleaning system allows absolutely reliable, reproducible and yet gentle removal of soiling. A further advantage is that the generator can be used in combination with every compatible transducer of the same power class without the need for time-consuming adjustment procedures. Like the UMC generators, the power output can be set steplessly between 10% and 100% via power control. The system can be operated manually at the device, via remote control or from a PC.

Strong Orientation Towards Customers and Service

Alongside quality and innovation, service enjoys a high priority at Weber Ultrasonics. This ranges from consulting, through project planning and production, to maintenance and training for customer employees. Plus, the company also has its own technical centre, where we are able to perform specific trials with sample parts together with our customers where necessary. This enables us to plan and realise ultrasonic equipment tailored precisely to your individual requirements and needs for every application case.
The company’s strong orientation towards its customers is also demonstrated in the foundation of international subsidiaries such as Weber Ultrasonics America, which came into being in 2009. The subsidiary based in Clarkston, Michigan looks after the American market and has its own manufacturing plant. An international sales and service network with numerous sites in Europe and Asia is also available to customers. www.weber-ultrasonics.com

Author: Doris Schulz
For Information:
Sabine Fragosa
Weber Ultrasonics GmbH
Im Hinteracker 7
76307 Karlsbad-Ittersbach, Germany
Tel. +49.7248.9207-0
E-mail: mail@weber-ultrasonics.de