Questions_and_Answers_2_0003.pdf

Turbine Shaft, Coupling, and Ringfeder (Ref: b.5)

Question:

Detailed drawings of the turbine shaft, coupling, and Ringfeder assembly are needed to properly quote machining and fitting work. PWS notes these drawings are “available upon award,” but they have not been provided for quoting purposes.

Answer:

This is a listing of associated manufacturer drawings. These drawings are not owned by Bureau of Reclamations and are not available for distribution:

James Leffel & CO drawing numbers:

o 47900-A (Runner) o 54591 (Runner & Shaft Mods Chandler Pump Unit 2 34”LL Vertical Turbine) o 51242 (Wearing Rings-Stationary) o 47946 ( Head Cover) o 47895 (Bottom Ring, Facing Plate and Wearing Ring)

Worthington Pump and Machinery Corp drawing numbers:

o RW-107006 (42-NA-57 T.V. VOL. Pump Sectional Elevation)

Other information:

The machining on the shaft is as follows: A 12 inch length of a steel tapered shaft, starting at an 8 in diameter tapering down to a 7.156 inch diameter would need to be machined to 7.156 inch diameter. As well remove and fill the key/keyway. See picture below.

Turbine Runner Elevation (Ref: b.6)

Question: Additional information is needed to match the elevation of the new runner to the existing runner. Specifically, baseline elevation data, reference points, and tolerances are required.

Answer: There isn’t a drastic change in elevation from the original layout to the modified design. One would use the Ringfeder to secure the runner to the shaft then make any adjustments to the runner elevation based on the measurement from the runner to the runner shaft flange.

Bearings (Ref: d.1)

Question: Number, type, size, and specifications of all bearings included in scope are needed to properly quote inspection, testing, and refurbishment.

Answer: There are 2 Guide bearings. The pump guide bearing and the turbine guide bearing are a split sleeve style journal bearings. The inside diameters of these two bearing are just under 8 inches. They are about 6 inches deep. There is 1 Thust bearing.

exact size of the thrust bearing shoes is unknown. There are 4 shoes of a tilting pad Kingsbury design. See attachment titled Bearing Rehabilitation for further details.

Impeller/Runner Wear Ring Finish

Question: The PWS specifies certain tolerances for the rotating and stationary rings. We request clarification: Do they mean the ID needs to be finished before installation?

Common practice is to finish the OD after installation, so we want to confirm the intended procedure.

Answer: The inside diameter of the stationary wear rings are to be final machined once in place (USBR is to install the stationary rings, the contractor is to do the final machining, as noted in the PWS). Machine the outside diameter of the rotating wearing rings to fit the installed and final machined stationary rings (This machining is also to be done by the contractor. USBR is to install the rotating rings on the impeller, as noted in the PWS)