Attachment_8_Statement_of_Work.pdf

Document No.

140R3019R0001

Document Title Turbine and Generator Hydroelectric Component Manufacturing and Rehabilitation IDIQ

Attachment 8 - Statement of Work Delivery Order “Facing Plates and

Break-off Screws”

STATEMENT OF WORK

FACING PLATES AND BREAK-OFF SCREWS

FOR HOOVER DAM UNIT A6

Delivery Order

SUMMARY

For FY20XX turbine generator overhaul, Hoover Dam needs two sets of 304L stainless steel facing plates and associated “break-off” retaining screws, for Unit A6, based on the attached design drawings. One set is the upper ring assembly and associated screws. The second set is the lower ring assembly and associated screws.

The facing plates shall be machined and ready for installation. The break-off screws shall be threaded and ready for installation. All hole locations in the plates shall be derived from using the old plates as templates.

QUANTITIES

This delivery order is for a total of two rings consisting of 16 face plate segments and 450 break-off screws.

DELIVERY SCHEDULE

1. Unit A6 existing facing plate templates for locating the holes in the new plates will be available for transport by the contractor on January 10, 20XX at the Hoover Dam Warehouse.

2. Unit A6 facing plates (two sets, qty of 16 segments) and break-off screws (qty 450) must arrive at the Hoover Dam Warehouse by January 31, 20XX. The priority set of plates shall be for the bottom ring, in the event there are any production delays.

SHIPPING

The contractor shall provide all shipping FOB destination:

Hoover Dam Central Warehouse Highway 93 Boulder City, NV 89005

Hoover Dam Central Warehouse receiving hours are 6:30 A.M. to 3:30 P.M. PST, Monday – Friday.

The Government shall be notified 3 business days in advance of delivery so that rigging, crane and a storage site are made available for unloading.

DESIGN

Overall dimensions

Facing plates and break-off screws per attached drawings:

Unit A6: Bureau of Reclamation drawings 45-301-9247 and 45-301-9331.

Material

Facing plates: ASTM A24-04, Type S-21800, Nitronic 60 stainless steel plate, 1.50 inches thick.

Break-off screws: Type 304 stainless steel 1-1/2 inch hexagon bar, ASTM F 593-95, F837-91, Group 1 Rockwell hardness B74 (ASTM E18-97a).

Templates for facing plate screw hole and wicket gate hole locations

Hoover Dam shall furnish the Contractor complete sets of facing plates as templates for locating screw and wicket gate holes. Hoover Dam will label each plate segment such that the new plate segments will match the old plate segments for dimensional variations, offsets, etc. The templates must be used because the screw holes and wicket gate holes do not exactly match the design drawings. The Government will finish machine the inside dimension for the wear plates to match the head cover and discharge assembly.

Solicitation No. 140R3019R0001

Lifting-eye threaded holes for handling

In addition to the holes shown on the design drawings, the contractor shall drill and tap (2) 1”- 8 UNC eye-bolt holes per facing plate segment between wicket gate holes on the neutral axis for balanced handling of plate segment. Provide (32) 1”-8 x 2” minimum thread length 304 stainless steel slotted head screws, with a relief for welding screw in place after tightening. These screws will be used to plug the lifting eye holes after assembly. See details on Facing Plate Drawing.

Facing plate machining details

The contractor shall machine and furnish each set of facing plates (8 segments per set) in accordance with the drawings and these specifications. If there is a discrepancy between the facing plate dimensions stated in the drawings and the Government-furnished templates, the dimensions of the Government-furnished templates take precedence.

Inside diameter finish 125 µ inch ANSI B46.1-95: The ID is expected to be 185.875 inches to allow ⅛ inch material per side for in-place machining after assembly. This dimension will be verified on disassembly of the unit.

Outside diameter finish: The reference OD is 220.750 ± 0.005 inch. This dimension will be field verified after disassembly of the unit. Finish = 63 µ inch, ANSI B46.1-95.

Thickness tolerances: + 0.000/-0.002 inch, parallel 0.006 inch, flatness = 0.006 inch. Finish = 63 µ inch, ANSI B46.1-95.

Edges: square as shown on the drawing.

Ends: ⅛ inch bevel 45°, top and inside diameter face for welding in field.

Break-off screws

For manufacturing the new break-off screws for the turbines, Hoover Dam shall supply the contractor at least 1 used screw for determining final thread dimensions. The used screws will be available after disassembly of the unit along with the facing plate templates.

Approximate sample size – 1 inch nominal thread diameter x 2¼ inches long (less drive head). Final thread dimensions will be determined from the used screws described above. The contractor must size the break-off neck diameter to allow break off at 300-350 ft-lbs. The entire cross section of the break must be above the level of the surrounding facing plate. Note: during installation, after the ⅛ inch chamfer is welded all surfaces are ground flush by Hoover Dam.

Submittals

The Contractor shall submit test reports of the metallurgical properties (material strength, chemical, Brinell hardness) of the metals used to fabricate the facing plates. The test reports shall be submitted for Hoover Dam approval; the Contractor shall submit the reports upon material purchase and Hoover Dam will approve or disapprove within 2 business days of receipt of reports.

Final payment will not be processed until two AutoCAD drawings are delivered to Hoover Engineering to reflect the “as manufactured” facing plates and screws.

PAYMENT

The Contractor shall invoice for lump-sum payment as described in the Delivery Schedule section above, to include the delivered material, associated costs and labor. Payment shall be for Unit A6 facing plates and break-off screws.

Solicitation No. 140R3019R0001

Document No.

140R3019R0001

Document Title Turbine and Generator Hydroelectric Component Manufacturing and Rehabilitation IDIQ

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