I am looking for companies who provide generator cleaning services. The lower end turns on one of our pumped-storage units were contaminated by turbine oil mist when our mist extraction fan failed several years back. The oil has since collected brake dust, metals, and some asbestos fibers. We...
I would like to relocate our residential 3-ton A/C condensor so I can build a patio. I'm planning on running the line set underground in a 4" PVC chase. The underground run will be 15' to 20' long and sloped back towards the evaporator. I'm debating on if I should have the contractor install...
We have a 100MW pumped-storge unit that is running with an uneven air gap. Nominal air gap is 0.700 inch. Eccentricity is 0.065 inch. The winding is going on 30 years and is showing weakness. We are in the process of procuring a new winding and big question is, should we risk moving the...
A contractor managed to gouge our generator rotor in the process of removing the rotor poles. We've taken a metal sample and found the base metal is similar to AISI 1137 but with low manganese and high copper. My primary concern is the high sulfur content.
The contractor needs to repair the...
I need to measure the torque applied to the shaft of a 42" butterfly valve. Head against the valve is around 1000 ft. The valve was adjusted to eliminate leakage. I am concerned we may be torsionally overloading the valve shaft and so I would like to measure the torsion in the shaft as we...
I posted a question regarding running DX linesets below grade last week. I have distilled two solutions from the responses I received, modify the system for pump-down operation and add a suction accumulator.
Now I'm wondering, which is better? Which presents greater risk? Is there value in...
I would like to relocate our A/C compressor/condensor unit approximately 25' from its current location. This will allow me to construct a patio as well as reduce the amount of fan noise transferred into the house. I would like to run the liquid and vapor lines under ground in a PVC conduit...
I am currently responsible for specifying portable machine testing and monitoring equipment for use on 14 small hydroelectric generators. All the units are vertical francis units with three fluid film guide bearings and a single thrust bearing. These are low speed units with the fastest unit...
I am tasked with correcting a hydraulic cylinder scoring problem. My current proposal is to use rod wipers to prevent material from getting trapped between the rod and close fitting sleeve, 1/32" radial clearance. My problem is the sleeve and supporting structure is split to permit removal...
I am writing specifications for a new hydraulic piston stem for a single action cylinder. The stem will be fabricated from 17-4PH H1150 stainless steel which has twice the tensile yield strength as the original copper-nickel alloy. The stem is 3" in diameter except for a 4.75" diameter knuckle...
I am preparing a specification for turbine oil for use in our hydroelectric generators. Our guide specification calls for a maximum acid number of 0.5 mg KOH/g after 1000 hours TOST. Most literature lists the the total TOST time or time to reach 2.0mg KOH/g. Does anybody know what the acid...
I am preparing a specification for turbine oil for use in our hydroelectric generators. Our guide specification calls for a maximum acid number of 0.5 mg KOH/g after 1000 hours TOST. Most literature lists the the total TOST time or time to reach 2.0mg KOH/g. Does anybody know what the acid...
I am a mechanical engineer who needs some structrual engineering advice. I would like to construct a trellis to shade a portion of our future deck. The shading element of the trellis will be 2X6's set on edge. I may have up to 20 "joists" depending on the final dimensions of the trellis. My...