Seal 2 of horizontal end-suction pump under pure water operating conditions
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This post was last edited by wang527746 on 2017-6-10 at 10:46. With the horizontal end-suction pumps currently in use, when the medium transported is pure water (with a conductivity of less than 0.5 μs/cm), it causes corrosion on the surface of the silicon carbide mechanical seals. Has anyone encountered this issue? The photos are as follows: http://bbs.hcbbs.com/forum.php?mod=image&aid=1269662&size=300x300&key=09b176d2073d633b&nocache=yes&type=fixnone http://bbs.hcbbs.com/forum.php?mod=image&aid=1269663&size=300x300&key=03a1cffdd6baf1b1&nocache=yes&type=fixnone These are photos of the static and dynamic rings of the mechanical seal; the dynamic ring has damage in the form of dot-like spots that appear to be corrosion marks.
This isn’t corrosion; the material is silicon carbide, it seems to be wear.
It’s not corrosion; it should be wear
It’s obviously worn down by impurities. Is there a filter? Clean it up. The medium is water; there should be no mechanical seal for the cold water circuit. It must be cooled and lubricated by the medium itself. If such a seal does exist, would scaling become severe if the pipes are cleaned?
It’s likely a material issue; if the static ring is corroded, a similar situation should occur as well. In mechanical seals with this design, the material of the rotating ring is usually graphite
It’s silicon carbide; the manufacturer’s response was that the water quality is too pure, which causes corrosion of the sealing surfaces
Water with too high purity is also weakly acidic, and the acidity of water cannot corrode silicon carbide.
This is a pipeline pump; the standard seal used for it is of the rubber cup type. You can choose other types of rotating and stationary rings made of cemented carbide, but they are more expensive. While this may increase the cost, it helps to reduce the failure rate. In the long run, issues related to labor, production losses due to failures, and material problems can all be avoided by using such materials. These days there are too many fake products in China; when something we buy malfunctions, we have to take samples ourselves to third-party laboratories for testing and to obtain reports. As a result, we no longer trust qualified suppliers at all