Maintenance issues with Hammett shielded pumps
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I’m a beginner when it comes to repairs; I have some questions regarding the repair of Hammett shielded pumps As shown in the figure, the technical requirement is that the theoretical clearance of the shielded pump should be 2.9 mm before the impeller is installed, and 1.9 mm after it is installed. Why is there a reduction of 1 mm between these two values? What causes this? Thank you
I haven’t used this device before, so I’m not sure if a 1mm spacer was added to the back side when the impeller was installed. I hope experts can help answer this
I saw it online; I’m not sure if that’s how it’s adjusted
The Dalian Empire makes such adjustments by distinguishing between unbalanced and balanced states; is Haimitik the same? Has anyone who has serviced a Haymeccanich shielded pump shared their experience?
Adding a 1mm gasket behind the impeller is intended to adjust the axial clearance between the impeller and the rear cover; will this affect the shaft play?
It shouldn’t be the case. Could it be that shims were added at the bearing seat location? I hope those who have serviced this pump can share their insights
The theoretical axial displacement of the Hammett pump before the impeller is installed is 2.9 mm, while it is 1.9 mm after the impeller is installed. With the impeller in place, the rotor is in its centered position; as long as the value remains within these two ranges, it indicates that all components are properly installed. The dimensions of each component in Haimi are fixed; once it is installed in place, no adjustments are needed.
Why does the shaft runout change before and after installing the impeller? Shouldn’t changes in shaft runout be achieved by adding or removing shims at both bearing seats? Is the change in flow rate due to the impeller? Is there contact between the impeller and the rear wear plate?
Before installing the impeller, the front sliding bearing sleeve and thrust disc were not in place, so it was larger; after the impeller was installed, all components of the rotor were in place, and thus it became smaller. The clearance value given in the drawings serves as a reference for inspection; if the measured value is close to this reference value, it indicates that all components have been installed properly. If there is a large difference, further inspection is required.