in Electrical Systems
Exploring the Myths
Reliability takes on a slightly different meaning when talking about items that will come in contact with the human body, such as pills from forming machines or medical testing or surgical instruments. In these instances, it is imperative to remove dirt, debris, and abrasive contaminants, as well as molds and toxic chemicals that can make humans sick.
This is an issue especially prominent in the pharmaceutical industry where manufacturers actually need to validate their cleaning method per FDA requirements. All residue must be removed from the equipment prior to manufacturing the finished product.
In addition, if parts need to go to a plating or coating stage, they need to be exceptionally clean for the coating to stick. Finished parts generally cannot go to end users with cutting fluids on them.
Equipment that's not properly cleaned can become unreliable and affect the reliability of the part it's producing. Without industrial cleaning to keep manufacturing equipment free of dirt and grime, parts wear faster, breakdowns occur more often, and efficiency and productivity suffer.
The flow of fluids, lubricants, heat, and air all suffer when parts become dirty. Increased friction means greater heat buildup, which may lead to premature equipment failure.
For equipment that undergoes routine maintenance, more thorough cleaning can extend the time between scheduled maintenance, which keeps machines running longer and eliminates downtime. If a machine or component is not cleaned well enough during routine maintenance, then it will need to be cleaned more often, shortening the time between scheduled maintenance.
The result is lost productivity due to a production line that is frequently down. Furthermore, today's manufacturing plants are made up of many complicated systems in motion at all times. This includes employees and equipment. As all good business people know, production flow is critically tied to revenue, so interruptions to production-especially chronic disruptions-can severely impact revenue.
Different cleaning systems
Industrial cleaning equipment is most often found at the end of a parts manufacturing process or in settings where parts must be regularly cleaned to function at peak efficiency. An industrial washer is a machine that removes contaminants from the surfaces of a part or component before it's sent to the next step in the manufacturing process.
Depending on how the part is made, the foreign materials can include machine oil, casting sand, metal shavings, polishing compound, and even human skin and oil. To expedite the process and manage labor costs effectively, manufacturers often use an industrial washer to clean the parts rather than spend the time and money to clean each one by hand.
Different types of industrial cleaning equipment remove contaminants with varying effectiveness, depending on the intricacy of the part.
For example, almost any type of system can clean a smooth, highly polished surface, whereas complex and intricate parts require a more sophisticated cleaning process. If a part has blind or drilled holes, internal passageways, sharp inside corners, or rough surfaces, removing contaminants for improved reliability can be problematic.
Since any contaminant can cause reliability issues, starting with the cleanest possible surface is imperative, and choosing the right industrial cleaning equipment becomes paramount.
Spray washers or power washers operate much like a dishwasher, with revolving high-pressure water jets that spray the parts to remove foreign materials. This type of industrial cleaning unit is used for general cleaning and removing gross contaminants, such as heavy dirt or rust, from large, smooth, and/or flat-faced surfaces.
A good example of an effective use of a spray washer is for the external surface of a large steel mold or the external surface of a car engine to remove grease and dirt. A spray washer will not perform any precision cleaning and is best suited for raw external surfaces.
For example, a spray washer is not a good choice for cleaning the internal exhaust ports of an engine because the streaming water can't necessarily get into those hidden areas.
Immersion cleaners soak parts in cleaning solutions to dissolve the contamination from the surface. Immersion cleaning is a better option for cleaning irregular shapes that have surfaces that are difficult to reach with spray washers. Typically, the parts are placed in a basket or barrel and the process can include agitation.
Solvent cleaners are a specific type of immersion industrial washer. Parts are bathed in solvents like acetone, naphtha, or mineral spirits. This type of cleaner is very effective at removing oil and grease, and sometimes requires a special enclosure to control the dangerous vapors and hazardous waste materials it generates.
Manual cleaning involves cleaning done by hand, often using toxic chemicals and an endless variety of implements, including rags, toothbrushes, wire brushes, cotton swabs, air compressors, fingertips, and more. Not only is hand labor the most time intensive industrial cleaning method, potentially wasting many hours of manpower, but the cleaning itself often is hit or miss-nooks and crannies that cannot be seen or reached don't get cleaned.
Sometimes, even parts cleaned in immersion tanks don't come out clean enough and require additional hand cleaning. Manual cleaning may be the best option for manufacturers that have a very low volume of parts to wash. A cost-benefit analysis can help determine at what volume an industrial washer would make sense.
Outsourcing parts cleaning to a third-party is a route that some manufacturers take when they find that manual cleaning is uneconomical within their operations. Outsourcing has some disadvantages as well, though, chiefly that manufacturers must accumulate parts before sending them out to qualify for a bulk discount. The time it takes to accumulate enough parts can impact lead times and cause production delays, not to mention the personnel time spent on, and cost of, shipping, packaging, and paperwork.
Ultrasonic cleaners are used when a part is very complex, it needs to be super clean, or the manufacturer wants to save on labor and energy costs. Unlike spray washers, immersion cleaners, or using solvents, industrial ultrasonic cleaners decontaminate at a near-microscopic level and can clean threads, drilled and blind holes, sharp inside corners, rough surfaces, and inaccessible internal cavities not reachable by other types of industrial washers.
When items are placed into an ultrasonic cleaning tank using environmentally friendly, water-based cleaning soaps, an energy-converting transducer produces sonic frequencies approaching 40,000 cycles per second. These high-frequency sound waves produce millions of microscopic vacuum bubbles that implode when they come in contact with a surface. Energy is released by the creation and collapse (called cavitation) of these bubbles.
The resulting shock waves break up and lift off dirt, residue, and other contaminants. The implosions work similarly to small vacuum cleaners that literally pull off caked on residue from any area, removing contaminants down to hundreds-of-thousandths of an inch in size.
Manufacturers that are having trouble achieving the level of cleanliness they want will turn to an ultrasonic cleaner. Due to its gentle nature, ultrasonic cleaning also is suitable for industries like printed circuit manufacturing. When the proper cleaning frequencies are used, ultrasound won't damage the final product.
Cleaning and safety
The type of industrial cleaning equipment manufacturers choose has implications for worker safety. The less contact workers have with the parts and equipment they are cleaning, the less likely injury will occur somewhere during the process.
Solvent parts washers use toxic solvents, which are dangerous for a number of reasons. First, they are extremely volatile. Workers exposed to the vapors can experience both short- and long-term health effects. In addition, the vapors are flammable, which means accidental introduction to heat from any source could start a fire or trigger an explosion.
Solvents require special handling, storage, reporting, and personal protection equipment while in use. They are toxic to wildlife if accidentally spilled or released, and they pollute the atmosphere. The vapors must be vented and captured when the washer is used, and spent solvents must be disposed of as hazardous waste, adding to the operating costs for the unit.
Because the risk of fire and explosion is so high in places where solvents are stored and used, insurance underwriters may require higher deductibles and higher premiums for those facilities. Manufacturers may also be required to install and maintain extra fire protection systems like sprinklers and fire extinguishers around solvent parts washers, and could be subjected to extra inspections from the fire marshal and insurance carrier.
An ultrasonic cleaning system, on the other hand, has none of these issues since it usually cleans with water-based detergents that are nontoxic and nonflammable.
Tools are another safety issue. Cleaning parts by hand often requires wire brushes, high-speed power tools, scrapers, files, sanders, utility knives, and hand picks. All of these tools have the potential to injure workers during use, from cuts and scrapes to puncture wounds. Not to mention that hand cleaning also requires the use of spray solvents, degreasers, corrosive alkalis, and acids.
Not only are most of these chemicals injurious to the body in some way-attacking workers' skin, lungs, vital organs, and eyes-they are even more dangerous when used in the wrong combinations.
What this all boils down to is that while cleaning equipment and parts seems mundane, it is an essential component to a profitable enterprise. Manufacturers have many variables to take into consideration, including how parts cleaning affects their product reliability, productivity, and worker safety.
Manufacturers each need to do their own analysis to determine the solution that works best for them-in a nutshell, what makes their lives easier and makes their businesses most profitable.
Article courtesy of Plant Engineering.