Industrial cleanliness involves more than just washing to make something clean. When a washing process is part of production and the washed goods are to be used or processed in the next step, there are sometimes also requirements regarding the after-treatment of the goods.
A cylinder head that is to be torqued should maintain the same temperature as the engine block, and if it is not dry in all its cavities, residual washing fluid can cause problems after assembly. Goods that are to be stored or transported after washing may need corrosion protection, and if the shape of the goods is complex and they have threaded bottom holes, traditional washing techniques may not always be sufficient.
For these and other more difficult conditions, Viverk has developed and produced various features and add-ons that can help achieve the extra cleanliness that is required to make the goods ready for use immediately after washing.
Viverk has a well-developed method for integrating ultrasound in combination with, for example, Flow-Jet washing. The ultrasound provides better mechanical action and efficiently cleans away dirt that is difficult to remove. To get it completely and dazzlingly clean, we use a patented technology called PZT. This is so effective that it is approved for goods with very high cleanliness requirements, for example in the healthcare sector. With an integrated ultrasound cleaner, it is often possible to completely replace mechanical or manual cleaning with solvents.
For goods with deep/long holes and complicated geometries, we recommend flushing with a lance. Using a pressure adapted to the characteristics of the goods, the lance flushes through the goods and cleans all the surfaces thoroughly. The lance flush can also be combined with a rotating nozzle if required.
A well-known problem in industrial sectors is removing dirt and chips from bottom holes (holes that do not go all the way through), especially if they are threaded. Chip Clean has a specially adapted flushing plate with nozzles positioned specifically for the particular goods that are to be cleaned. Under high pressure, Chip Clean flushes the bottom holes of the goods while moving back and forth so that everything is completely clean.
In some situations, such as when measuring micrometers (thousandths of millimeters) on engine blocks and cylinder heads, it is important that the goods that are washed reach a certain temperature quickly. Aerosol cooling involves “fogging” the aerosol, consisting of water, during the vacuum process, which evaporates on the goods. The result is that goods can be cooled up to seven times faster than with conventional cooling.
Rotation of goods
The most common and simplest part of a flush wash is rotating the flush arches to wash all sides of the goods. But this is sometimes not sufficient to achieve the required cleanliness. By rotating the goods horizontally or vertically instead of rotating the arches, higher pressures can be used and hard-to-reach sides of the goods that might otherwise be difficult to access can be reached.
Oil separators can be used to separate oils from the washing fluid, which is thus purified and has a longer life. In the oil separator, oils and fats are separated and collected for recycling and can, in some cases, also be reused.
Viverk’s AU-OL oil separator is designed to remove oils, surfactants and other grease-based contaminants from washing fluids. The methods that are used are based on density separation of oil and water (gravimetric oil separation) and on separation by droplet formation (coalescence separation).
These allow mixed oil residues to be collected and separated quickly and efficiently, while solids sink and collect as sludge at the bottom of the oil separator. The oil residues are separated by coalescing the oil droplets, which involves larger oil droplets being formed that no longer follow the flowing water but float to the surface and accumulate in the oil gap where the accumulated oil is overflowed and drains into a collection vessel while the cleaned washing fluid is returned to the wash tank.
An oil separator collects the surface fluid from washing tanks, and purifies and circulates the washing fluid in a continuous cycle. It acts as a filter for oil and dirt.
Drying of washed goods
There are a variety of techniques for drying goods after washing, and at Viverk we generally use the technique or techniques that give the best results for the specific task. The three most common techniques are:
Warm air carries more moisture. Rinsing goods with warm fluid heats them up and they dry faster. With the evacuation of humid and heated air, the goods dry relatively quickly.
- Suitable for goods with simple geometries without holes or cavities
- Effect: Low-effect drying
Hot air blowing
The drainage process is greatly accelerated if the goods are also blown with compressed air. The best effect is obtained when directed nozzles or air knives are used. Heated compressed air makes the method even more effective.
- Suitable for goods without holes or cavities
- Effect: Medium-effect drying
A vacuum dryer dries goods by sucking out all the air to create a vacuum. Water evaporates differently at different pressures, and when the pressure approaches a vacuum, the water boils away and disappears with the help of the vacuum pump.
Vacuum drying is good for integration into chamber and Flow-Jet washers, which can then also ensure that the goods are kept at a sufficient temperature to avoid freezing.
- Suitable for goods with complex geometries and holes or cavities
- Effect: High-effect drying
A stand-alone vacuum dryer like this one can be used to add extra drying to an existing washing system.
Heat recovery can reduce the cost of heating and reduce the impact on the environment by cutting energy consumption. Just by capturing and reusing the excess heat, a lot can be gained at low cost, but greater utilization of the excess energy and more resulting benefits are also possible by using smarter and more advanced recovery technologies.
Heat exchangers and heat pump technology
Heat exchangers recover much of the heat contained in heated evacuation air and steam that is extracted from the washing chamber during washing. This saves both heat and water, which can easily be processed and reused.
In addition, if energy recovery is used with heat pump technology, the energy savings are several times higher and the environmental benefits even greater. An exhaust air heat pump with a COP value of 3.48, which has been adapted for industrial purposes and can withstand really tough operating conditions, also has a very short pay-off time in the case of long operating times, and can be controlled fully automatically by normal control equipment.
The washing fluid is used up gradually and diluted when new water is added. The chemical mixture is also used up and needs to be replenished to maintain the washing effect. But the chemical mixture also has to be right. Insufficient dosing of detergents usually leads to poorer cleanliness, while excessive dosing of detergents can lead to other problems.
With Viverk’s dosing equipment, extra detergent is added automatically based on the characteristics and chemical balance of the washing fluid. An optimal washing result is thus always obtained at the lowest possible cost.
With automatic dosing of chemicals, the washing fluid maintains optimal performance for a long time.
Washing using ultrasound
Ultrasound means sound waves with a frequency higher than the upper limit of human hearing. Ultrasound itself cannot make things clean, but when used in washing fluids, it creates pressure waves that can help get rid of contaminants and deposits on goods that are otherwise difficult to remove.
Ultrasound washing is a washing technique that can be integrated into bath washers such as Flow-Jet washers, where it acts as a complementary washing technique for really tough conditions.
- Suitable for very soiled goods with complex geometries and holes or cavities
- Effect: High-effect washing