PRE-TREATMENT , SURFACE PREPARATION , DEGREASING & CLEANING
Variations of process within the hermetically sealed tank are possible using sprays of cold or hot condensed solvent , immersion with or without ultrasonics and revolving baskets to cover most of the problems experienced when processing machined and fabricated parts . Continuous external distillation of the contents of the vapour generator is also an option depending on contamination .
The alternative technology is much simpler and uses well tried techniques not requiring the long recovery times of the hermetically vacuum sealed processes . The multilevel system uses a standard vapour degreasing tank design with a sealed loading section above the process tank . Components to be cleaned loaded in work baskets or jigs are fed to the load section by hand or conveyor , an internal platform raises and lowers the baskets in controlled cycles .
Loading complete - the load enclosure is sealed to completely isolate the process . Then seal on the process tank is opened and the basket automatically lowered into the cleaning section which can be simple condensation cleaning or immersion cleaning with or without ultrasonics or power sprays . Revolving baskets can also be added to improve cleaning in blind or through holes or oil ways in castings and fabrications .
On completion the basket rises to the area where the condensation coils are located , and parts allowed to drain and dry , basket raises into the load section when the process tank is sealed . A fan circulates air within the load area which can be recycled through carbon absorption systems if no external exhaust is preferred .
As baskets entering the loading space contain parts drained and dried only very small amounts of solvent are carried in the exhausted air which is monitored to ensure compliance with appropriate legislation . When this is complete the seal opens fully for removal of cleaned components . The loading section can be fitted with top or side seals allowing baskets to flow through on conveyor systems or be removed by hand or hoist . No solvent enters the work area .
Both processes will produce parts cleaned to the highest standards but the choice of which offers the best solution needs a little more consideration .
The hermetically sealed vacuum process is complicated with the need to move liquids in the machine . It is relatively slow as the carbon adsorption process has to remove high levels of solvent from the recirculated airstream from the process tank . This is inefficient as adsorption rates for carbon fall rapidly with increasing saturation . Final levels of solvent in the tank when the lid or loading door opens will be dragged into the workshop and the area where the operator is working . Long process cycles reduce throughput .
The simpler multilevel systems where movement of liquids is not required are more efficient and offer much faster process times . Cost of manufacture is also reduced as no liquid movement or vacuum is involved . The extracted loading section ensures no leakage of solvent into the work area giving complete safety for operators and factory staff .
Both designs of process machines fully comply with the emission regulations of the EU and U . S authorities . Which to choose will depend on many factors which should be discussed with equipment and solvent suppliers who have the experience to advise on which offers the best process for the application . Equipment and solvent must work together , so it is advisable to ensure that the suppliers co-operate to offer a package with high levels of responsible care and product stewardship to ensure the best and safest installation . EnviroTech personnel and distributors are trained to work with our equipment suppliers to advise on the use of ProSolv ® 5408e for the most satisfactory outcome .
The “ Condensation cleaning ” process still gives the highest levels of economical cleaning with minimum energy usage , low footprint on the factory floor , safety for the operator , and high production rates with low solvent usage and environmental impact . With the new generation of sealed cleaning machines its future as the process of choice is assured .
Photograph of Solvac equipment courtesy of C & C Hydrosonics ( part of Crest Corp .). https :// www . cchydrosonics . com /
FURTHER INFORMATION
ProSolv ® 5408e vapour degreasing solvent manufactured in the United Kingdom and available on short delivery times through our dedicated team of distributors worldwide .
Please visit our website https :// www . envirotech-europe . com / prosolv5408e for information about other uses and applications for ProSolv ® 5408e .
Visit www . envirotech-europe . com / applications-and-case-studies for information about uses and applications for all EnviroTech Europe products .
For more advice , please telephone us on + 44 ( 0 ) 20 8281 6370 or use our website contact form .
42 MARCH 2022 read online : www . surfaceworld . com