CleaverBrooks 4WI, Руководство по эксплуатации, обслуживанию и запасным частям

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Firetube Operation Basics
1-4 750-211 (revised 2009)
Promethean Boilers, Model 4WI Manual
Firetube boilers are rated in boiler horsepower (BHP), which should not be confused with other horsepower mea-
surements.
Hot water is commonly used in heating applications with boiler supplied water to the system at 180º F to 220º F.
The operating pressure for hot water heating systems usually is 30 psig to 125 psig.
Steam boilers are designed for low or high pressure applications. Low pressure boilers are limited to 15 psig design,
and are typically used for heating applications. High pressure boilers are typically used for process loads and can
have a design pressure of 75 psig to 350 psig.
Steam and hot water boilers are defined according to design pressure and operating pressure.
Design pressure is the maximum pressure used in the design of the boiler for the purpose of calculating the mini-
mum permissible thickness or physical characteristics of the pressure vessel parts of the boiler. Typically, the safety
valves are set at or below design pressure.
Operating pressure it the pressure of the boiler at which it normally operates. The operating pressure usually is
maintained at a suitable level below the setting of the pressure relieving valve(s) to prevent frequent valve opening
during normal operation.
The type of service that your boiler is required to provide has an important bearing on the amount of waterside
care it will require.
Feedwater equipment should be checked and ready for use. Be sure that all valves, piping, boiler feed pumps, and
receivers are installed in accordance with prevailing codes and practices.
Water requirements for both steam and hot water boilers are essential to boiler life and length of service. Constant
attention to water requirements will pay dividends in the form of longer life, less downtime, and prevention of
costly repairs.
Care takin in placing the pressure vessel into initial service is vital. The waterside of new boilers and new or remod-
eled steam or hot water systems may contain oil, grease, or other foreign matter. A method of boiling out the vessel
to remove accumulations is described in Chapter 3.
1.3 — Construction
Steam boilers designed for 15 psig and hot water boilers designed for 250º F at 125 psi or less are constructed in
accordance with Section IV, Heating Boilers, of ASME Code.
Steam boilers designed for operating pressures exceeding 15 psig are constructed in accordance with Section I,
Power Boilers, of the ASME Code. Hot water boilers designed for operating temperatures above 250º F or 125 psi
are likewise built to Section I of the ASME Code.