The US Army Corps of Engineers (USACE) has issued a presolicitation notice for the manufacture of tubes as replacement parts in the rehabilitation of heat exchangers that are used to cool hydroelectric turbine generators.

USACE’s Portland District will award a supply type contract to the winning tender for the Dalles dam power house. The contract is for two contract line items (CLIN), each for 1392 tubes, which need to be manufactured and delivered 120 days after the date of contract. The heat exchangers are used to cool the turbines; river water runs through the tubes while air passes around the outside.

The tubes should be:

• Seventy-four inches (188cm) long by 5/8 inches (1.58cm) nominal, and belled to 1.5 inches (3.8cm) at one end.

• Made of 90/10 CuNi, conforming to ASTM B111 for copper alloy.

• Tubing OD should be 0.750 inches (1.9cm), 5/8 inches (1.58cm) nominal, with a minimum wall thickness of 0.049 inches (0.12cm) to a maximum of 0.065 inches (0.16cm).

• Belled at one end to fit existing tube sheets.

• Finned, with the fins made out of copper and soldered. Fins should be spaced at nine per inch (2.54cm). Outside diameter of the fin should be 1.484 inches and fin thickness should be a minimum of 0.012 inches (0.030cm) and a maximum of 0.016 inches (0.040cm).

The deadline for responses is 17 November 2005.

CONTACT: Rose Caughie on tel: +1 (503) 808-4627. Email:

To request a copy of the request for quote (RFQ) register online at