77. SANITARY SEWER. Sewerlines from the powerplant and elevator towers in the dam deliver sewage to three collecting tanks. One tank serves the elevator tower in block 17 of the dam, the control room, and office areas. Another tank serves the central portion of the powerplant. A third tank serves the elevator tower in block 8 of the dam, the service bay, and the machine shop. The sewage is pumped from these tanks to the sewage disposal plant for treatment. Floor drains throughout the building are not connected to the sewage lines but have their own system discharging into the building sump.

78. HEATING. Heating of the powerplant is provided for the protection of equipment and personnel and for the comfort of the personnel. The heating load for the powerplant was based on an outside design temperature of 0° F. and an inside design temperature of 45° F. in all spaces except those listed below. Special higher inside design temperatures were used in a few areas as follows: office and control room 72° F.; machine shop bay and toilets 65° F. A

lower inside design temperature of 37° F. was used in the elevators and cable shafts.

The major heating capacity is furnished by water-to-water heat pumps which supply hot water to heat-exchanger coils installed in heating and ventilating units and air-conditioning units located throughout the powerplant. When the outdoor air temperature is below 65° F., the water-to-water heat pumps are energized. Additional heat is supplied where needed by electric natural convection and duct heaters.

79. VENTILATION. Ventilation is provided for the comfort and protection of personnel, the distribution and removal of heat, the relief of dampness, and the disposal of contaminated air. Approximately four air changes per hour of fresh air are furnished to the powerplant as a whole.

Exhaust fans are located in the building for removal of contaminated air from toilets, welding room, battery room, oil purifier room, and oil storage room. Excess ventilating air is relieved from the building through automatic louvers set to open under a static gage pressure of 0.125 inch of water.

80. COOLING. Cooling of the offices and control room is provided for protection of equipment and comfort of personnel. Cooling of the electrical gallery is provided for the protection of equipment. The cooling loads for the offices and control room were calculated using an outside condition of 95° F. dry bulb and 65° F. wet bulb, and an inside condition of 75° F. dry bulb and 59° F. wet bulb. The cooling load for the electrical gallery was calculated using an estimated powerload from equipment installed in the gallery.

The cooling is furnished by a water-to-water chiller which supplies cold water to heat exchanger coils in the air-conditioning unit. When the outdoor air temperature is above 65° F. the water-to-water chiller is energized.

D. MAJOR HYDRAULIC EQUIPMENT

81. TURBINE. On the basis of economic studies, the plant nameplate capacity was set at 900,000 kilowatts, utilizing eight 112,500-kilowatt generating units. The turbines were sized to match this rating at 450 feet net head, making the nameplate rating available for firm power to the power system about 90 percent of the time. The design (best efficiency) head

for the turbines was set at 510 feet, which is near the weighted-average operating head.

The turbine speed and setting were established jointly since they are mutually related. Some of the variables considered, evaluated, and judged were operating heads, tailwater elevations, cavitation factor (sigma), size of unit as affected by speed, building size, excavation required, and foundation conditions. From the studies it was determined that a unit speed of 150 revoluţions per minute and a distributor centerline setting at elevation 3140.00 were optimum for the Glen Canyon installation.

The turbines were designed by the manufacturer, but the design was controlled by detailed Bureau specifications. Principal specified operating requirements or conditions are as follows:

Rated output--155,500 horsepower at 450 feet effective head

Best efficiency--90 percent or higher at 510 feet effective head

Range of effective head---341 feet to 560 feet Specified minimum tailwater--elevation 3137.00

initial and elevation 3134.00 after degradation Casing design pressure--300 pounds per square inch

A summation of turbine statistics, controlling dimensions, and predicted operating characteristics, is shown on the hydraulic turbine data sheet, figure 185. Figure 186 shows a sectional elevation of the turbine.

Design and construction details are given in invitation No. DS-5234, and shown on the drawings of the manufacturer, the Baldwin-Lima-Hamilton Corp. Materials for the parts were specified, and unit stresses and fabrication methods for main parts were controlled by reference to the ASME Boiler and Pressure Vessel Code. Principal construction features include the following items:

Spiral case-Plate steel with field welded radial joints

Draft tube liner-Plate steel elbow type with two intermediate piers

Runner-Cast steel with stainless steel coatings on surfaces most susceptible to cavitation Head cover-Cast steel in half sections with bolted joint

Guide bearing-Babbit-lined, pressure-feed lubricated with external heat exchanger

Wearing rings-Stainless steel, removable and renewable, with replaceable inserts in stationary rings

Shaft-Forged steel with integrally forged flanged couplings

Shaft sleeve-Stainless, removable, and renewable Wicket gates-Cast steel with stainless steel coatings over critical areas

Facing plates-Stainless steel, removable, and

renewable

Stay ring-Cast steel with integrally cast stay vanes Grease system-Automatic unit centralized

The turbine design was carefully checked for correctness, completeness, and compliance with the specifications. Stress checks were made on the major parts and on doubtful stress-carrying items to insure conformity with the specified stress limitations. Some of the items found to be overstressed and requiring revision were stay ring bolts, draft tube pier nose, draft tube stiffening ribs and tie rods, operating ring retaining clips, spiral case jacks, spiral case mandoor, and gate lever key.

There were five orders for changes issued on the turbine contract. One of these was for changing the painting requirements; one was for revising the walkways, platforms, stairways, and handrailing in unit 1 to include visitor accommodations; one was for an additional stay ring erection spider to accelerate installation; and the other two pertained to furnishing centralized automatic lubricating grease systems in lieu of the originally specified manual grease systems.

A shop assembly of the nonembedded stationary parts and the rotating parts was made in Belgium at the shops of a Baldwin-Lima-Hamilton subcontractor, Cockerill-Ougree, where these parts were manufactured. The stay rings, discharge rings, and throat rings were manufactured in Pennsylvania by Baldwin-Lima-Hamilton, the prime contractor for the turbines, and shipped to Salt Lake City, Utah, for fitting to the pit liners, spiral cases, and draft tube liners, which were constructed by Chicago Bridge and Iron, another subcontractor for Baldwin-Lima-Hamilton (B-L-H). Final balancing of the runners and alinement of the combined turbine and generator shafts were done by B-L-H at their shops in Eddystone, Pa. Because of the shop and field welded construction of the spiral case, pressure tests of the spiral case and stay ring assemblies were made in the field.

Installation of the turbines was performed under the supervision of the turbine contractor's erecting engineer. The major portion of the turbine installation was done by the completion contractor, Ets-Hokin Corp. However, the turbine contractor's subcontractor,

Weight 1,220,000
Weight per h. p. 6.16 lbs.
Weight heaviest part. 91,500 lbs.

; at 100 percent of design head; 3985_c.f.s.

ns of runner 24.6 at 510 ft. design head when delivering 157,500 h.p. (Best eff. gate).
Ns of runner. 27.6 at 510 ft. design head when delivering 198,200h.p. (Full gate).
H.P, at 510 ft. (Design head). 198,200
H.P. at 5.63 ft. (Max, head). 229,800 ; at 10.4 percent of design head; 4230 c. f. s.
H.P. at 345 ft. (Min, head).
98,500 ; at 67.6 percent of design head; 3035 c. f. s.
H. P. at 440 ft. (Mfrs. Rated Hd.) 155,500; at 86.3 percent of design head; 3630. c.f.s.
H. P. at best efficiency equals 79.5. percent of h. p. at full gate.
Runaway speed at 560 ft. hd.
DIMENSIONS OF TURBINE

277 r. p. m. equals 184.7 percent of normal speed.

Dia. of shaft 40 inches.

440

Dia, of cover plate20.96 ft.

Number of wicket gates__24_

MFR'S RATED HEAD

420

Dia. at top of draft tube 12.67 Ft=Ds. Distributor & Elev. .Ft.

3140

4.625 ft.

Ouside radii of stay vanes 11.73 to 12.10 ft.
Distance from center line of distributor to top of draft tube.
Depth of draft tube 38.00 ft. equals 300.0 percent of dia. Ds.
Length of draft tube 58.83.ft. equals 464.4 percent of dia. Ds.
Width of draft tube 48.42 ft. equals 382.2 percent of dia. Ds.
Distance from center line of turbine to center line of scroll case inlet 18.5 ft.
Distance from center line of distributor to minimum tailwater, (Elev. 3133.64 ft.)
(One unit operating at full load)

PREDICTED CHARACTERISTIC CURVES
FROM MANUFACTURER'S
CURVE NO.6942 11-17-59

DATA

3-20-62

90

100

% EFFICIENCY

HYDRAULIC TURBINE DATA

GLEN CANYON POWER PLANT
U.S. DEPARTMENT OF THE INTERIOR
BUREAU OF RECLAMATION

Chicago Bridge and Iron, assembled, leveled, and alined the spiral case and stay ring sections, and tested the spiral case under a hydrostatic pressure of 450 pounds per square inch. Field erection, pressure tests, pressure embedment at 225 pounds per square inch, water passage calibrations, and run-in tests were successfully completed in accordance with the usual practice for these features.

During initial operation, the units were found to operate extremely quiet and smooth under the low power head available at this time.

Some of the deficiencies found during initial operation which required correction by the turbine contractor were inadequate securing of the throat ring which permitted loosening and rotation, insufficient thickness of the stainless steel coating on some areas of the runners (detected when checking minor cavitation, rusting, and pitting), brass shear pins that deformed rather than breaking cleanly when excessively loaded, set screws made of soft material that failed to properly hold the gate adjustment, and improper fitting of the throat ring at the runner discharge which caused cavitation of the throat ring. Also, during the initial operation period, the turbine contractor changed the full gate servomotor stroke from the machine capability of 15 inches to a limited 13-1/2-inch maximum stroke.

One turbine was to be tested after installation to determine whether the turbines met the efficiency and capacity warranties. Piezometer connections, installed on the turbines to permit future index tests of performance and future installation of flowmeters, were to be calibrated at that time.

82. GOVERNOR. The governors for turbine regulation are the oil-pressure cabinet-actuator type with electrically driven speed-responsive elements. Designing of the governors was done by the manufacturer, the Pelton Division of Baldwin-Lima-Hamilton Corp., but was controlled by detailed specification under invitation No. DS-5562. Details of the design and construction, including the various control and indicating features, may be found in the invitation and on the manufacturer's drawings. Basic design requirements for the governors were the foot-pound capacity and the minimum time for full gate stroke. The required foot-pound capacity was established at 441,700 foot-pounds by the turbine contractor. A 5-second minimum time for full gate stroke was set on the basis of the calculated speed rise for full load rejection and the corresponding water-hammer pressure created at the turbine. The

5-second minimum setting gives a calculated speed rise of 40 percent above normal for full load rejection and a water-hammer pressure of 682 feet at the turbine. The governors were set for a 5-second full gate stroke after tests determined this to be a safe operating condition.

The governor oil pressure is supplied by two 138-g.p.m., 30-horsepower, oil pumping units to a pressure tank where the operating oil pressure and level is continuously maintained for instant response to unit regulating requirements. The normal operating pressure at the governor pressure tank is 270 to 300 pounds per square inch. The tank has a total usable volume of 230 cubic feet which includes a reserve capacity below the alarm level corresponding to 265 pounds per square inch for three complete servomotor strokes with the oil pumps inoperative. This provision is a safety feature to provide sufficient energy for a limited operation and closure of the wicket gates in event of loss of power or pumping unit malfunction. Except for the servomotors which were a part of the turbine contract, all parts of the governor oil pressure system, including all interconnecting piping, were furnished by the governor contractor.

The governor control, indicating and protective features, as established to be essential and required by the invitation, include the following devices:

(1) Gate limit mechanism.-Operated manually at the actuator or electrically from the main control board.

(2) Speed changer.-Operated manually at the actuator or electrically from the main control board.

(3) Speed droop adjustment mechanism.-Adjustable manually at the actuator or electrically from the main control board for 0 to 5 percent speed droop.

(4) Normal shutdown mechanism.-Solenoid operated for automatic starting and normal shutdown of the unit.

(5) Complete shutdown and lockout mechanism.-Solenoid operated for normal-rate closure of the wicket gates, operated manually at the actuator or electrically by remote control.

(6) Hydraulic-type hand-control device.-For manual control of the wicket gates at the actuator.