conformance to requirements of the specifications including ability to
respond to load swings from the specified capacity to minimum turndown.
Operational test shall be under the supervision of a registered
professional engineer or a licensed power plant operator and shall serve to
prove safeties, controls, maintenance of stable combustion at low loads,
[proper coal distribution and combustion, and ability to operate without
furnace slagging,] [proper flame lengths and patterns to avoid flame
impingement on the tubes for oil firing,] and proper mechanical and
electrical functioning of each system. Test shall include items specified
in this section as well as items mentioned in the specification of the
particular pieces of equipment. Conduct tests with factory trained
combustion equipment engineers as previously specified. Test and record
steam quality, steam flowrates, flue gas temperature, percentages of carbon
dioxide, carbon monoxide, oxygen and nitrogen in flue gas and percent
excess air for each boiler at tested load and graphically present the test
data.
3.2.5.5
General Operational Tests
a.
Steady State Combustion Tests: Test fuel burning and combustion
control equipment with each of the specific fuels at the minimum
limit of the turndown range and at increments of 50, 75 and 100
percent of full rated load. Each test run shall be at least two
hours on each fuel and until stack temperatures are constant and
capacity and efficiency requirements of this specification have
been verified and recorded. Verify proper operation of
instrumentation and gages during the tests.
b.
Varying Load Combustion Tests: Test boiler continuously under
varying load conditions to demonstrate proper operability of the
combustion control, flame safeguard control, programming control
and safety interlocks. Conduct these tests after adjustment of
combustion controls has been completed under the steady state
combustion tests. Continue variable load operational tests for a
period of at least 8 hours.
(1) Sequencing: Boiler shall start, operate and stop in strict
accordance with the specified operating sequence.
(2) Flame Safeguard: Verify operation of the flame safeguard
controls by simulated flame and ignition failures. Verify
trial-for-main flame ignition, combustion control reaction and
valve closing times by stop watch.
(3) Immunity to Hot Refractory: Operate burner at high fire
until combustion chamber refractory reaches maximum temperature.
Main fuel valve shall then be closed manually. Combustion
safeguard shall drop out immediately causing the safety shutoff
valves to close within the specified control reaction and valve
closing times.
[(4) Pilot Intensity Required: Gradually reduce the fuel supply
to the pilot flame to the point where the combustion safeguard
begins to drop out (sense "no flame") but holds in until the main
fuel valve opens. At this point of reduced pilot fuel supply, the
pilot flame shall be capable of safely igniting the main burner.
When the main fuel valve can be opened on a pilot flame of
insufficient intensity to safely light the main flame, the boiler
shall be rejected.]
SECTION 15501N
Page 160
Previous Page
