I do not have access to any papers on the subject. Vertical shaft journal bearings are prone to oil whirl. A tri-lobe bearing with three axial grooves and three tapered lands is commonly used to stabilize a vertical shaft and avoid oil whirl. Do an internet search for "tri-lobe bearing"...
Tug, The axial grooves serve the purpose of breaking up whirl and whip which can pound bearings to pieces. The small hole would have have sprayed oil on a thermometer. The fact that there is now an embedded RTD does not change that. It costs money to change a design. Even if that change...
The A dimension would be measured with the springs removed or fully compressed. Cutting the nose of the cover to less than A allows the springs to be loaded, but not bottomed out.
Your pump could be purchased with or without pressure fed bearings. If it had a pressure fed oil to the bearings, the larger hole would have been the oil supply to the bearing. The smaller hole would have directed a small amount of oil to a temperature probe. There is probably a threaded port...
It is usually a single line for both. I have seen one compressor (1955 Clark) that had separate lines for thrust balance and seal chamber pressure control.
There are many options for the pivot on the back of the pad. The most common would be a button design with the button being a much smaller curvature than the bore it rests on. This is essentially a point contact which allows the pad to pivot in any direction. That point contact will tend to...
There is a setting within the governor / tachometer / OST system for the probes that are looking at that toothed wheel. I think it might be called gain. We changed this setting and altered the probe air gap to solve a buggy speed indication problem on a large steam turbine. All square toothed...
What is the tooth profile. In my experience, turbine manufacturers make toothed wheels with a square tooth design. The manufacturers of the governors and overspeed trip systems expect a gear tooth profile. This makes the system extremely sensitive to air gap.
Johnny Pellin
On condensing steam turbines, it is common to use the leakage from the high pressure packing to supply the sealing steam to the low pressure packing. If the leakage is not sufficient to maintain about 3 psi, a regulator will introduce low pressure steam. If the leakage from the high pressure...
I agree that resonance is the most likely cause. We have successfully mitigated this type of vibration on vertical motors driving vertical pumps by adding a tuned mass damper. Basically, we clamped a piece a steel bar stock to the motor and tuned it by changing the length and adding weights to...
It is not so simple. I have seen recip and centrifugal machines run to destruction from liquid even with well designed suction piping. Process conditions, machine design and piping design are all important.
Johnny Pellin
Too little information provided. Could be the electronic governor. Could be the I/P converter. Could be the hydraulic actuator. Could be the linkage. Could be the valve rack. Could be a worn out turbine. Could be steam conditions.
Johnny Pellin
If everything is symmetrical, the net thrust should be close to zero. The thrust bearing requires clearance, set when it is cold. When the thrust bearing heats up in operation, it needs room for thermal growth of the bearing and associated hardware.
Johnny Pellin
I have seen machines of this type experience elevated vibration as a result of increased radial bearing clearance, impeller rubs and cracked vanes. A detailed analysis of the vibration should help distinguish between these causes. The analyst may want to capture a coast down to compare the...
Does the bearing housing have a jam bolt coming down from the top, locking the bearing in place in the lower housing? If so, the fit between the bearing OD and the housing is less important. You could lap the bearing into the lower housing to restore the contact and re-babbit the bore. Of...
If you have to replace the first stage impeller to repair the damage, install an impeller with a higher NPSHr which results in a lower suction specific speed. I have used this exact solution for this exact problem on this exact service and proven over 30 years that the solution worked...
It looks like some of this leakage was coming from the point where the gland gasket (oring) crosses the casing gasket (Garlock or similar). This is a difficult spot to seal. Proper procedures for cutting the casing gasket at the face of the stuffing box is critical. Make sure you have...
