The main contrast between an oil-free sealed compressor and a standard piston compressor lies in their design and functionality. While the former uses a special sealing technique to prevent oil from entering the compressor chamber, the latter employs a piston to compress air.
In more detail, an oil-free sealed compressor utilizes a specially engineered coating or sealant to create a barrier between the air and the oil lubricant in the compressor. This prevents any oil from entering the compressed air, making it suitable for use in a range of applications where oil contamination is a concern. On the other hand, a standard piston compressor relies on a piston moving back and forth inside a cylinder to compress air, which means that oil is an essential component to lubricate the piston and the cylinder walls.
Overall, the difference in design and function between these two types of compressors has significant implications for their use in different industries and applications. Oil-free sealed compressors are typically used in food or medical processes where oil-free compressed air. Meanwhile, standard piston compressors are suitable for heavy-duty applications, such as automotive or industrial repair work.
The typical oil-free piston compressor is constructed using pig iron, resulting in numerous sand holes and limited modifiability. It features an open bottom or pressure balance holes, and screw holes that are often problematic to seal- leading to leaks. The cylinder head and cylinder gasket materials used are the same as commonly found in air compressors- simple flat gaskets, lacking any sealing grooves. Additionally, there is no shaft seal design, making this compressor unsuitable for gas compression with any specific requirements, such as air.
2) The use of an ordinary oil-lubricated piston compressor results in a significant amount of oil present in the gas produced. Even with the installation of gas post-treatment equipment, effectively removing the oil and gas from the final product proves challenging. Moreover, this type of compressor is not ideal for compressing and recovering high-purity gas due to the expensive and frequent replacement of filter elements and the need for specialized compressor oil.
