IS 8753 : 1977 Code for acceptance tests on stationary steam generators of the power station type

1 Scope

1.1 This Standard establishes the procedure for conductingacceptance tests on direct fired stationary steam-generating unitsof the power station type and presenting the test results intabular form.

It provides for the determination of the heat output and of thethermal efficiency. The heat output should be determined by directmeasurements. The efficiency should be determined by one of Thismethods:

Method A - where possible, from the establishment of a completeheatbalance, or

Method B - where this is not possible, or where the expectedaccuracy ofmeasurement of heat input or heat output is unacceptable, by

thedetermination of all losses.

In either case the thermal efficiency may be expressed in termsof either the net or the gross calorific value of the fuel.

The net thermal efficiency, based on the heat output reduced bythe thermal equivalent of the power used by auxiliaries, is notemployed in this standard. The power used by auxiliaries is to beseparately recorded in its appropriate units in the test report.

Provision is also made for the determination of the performanceof the draught plant and pulverizers, and also for thedetermination of steam purity, where such tests are required todemonstrate compliance with the provisions of a contract.

The question of contractual tolerances is outside the scope ofthis standard. The probable errors involved in performing a testmay be determined by combining the individual errors likely toarise from the separate measurements by one of the establishedstatistical procedures.

This standard applies to large direct fired steam generators,primarily of the water tube type, which may be equipped withsuperheaters, reheaters, economizers, air heaters, combustion andsteam temperature control equipment.

The water circulation in the boilers may be by naturalconvection or by pump or by a combination of natural convection andpump.

The steam generators may be fired by solid fuel, liquid fuel,gaseous fuel, or a combination of any of these fuels.

A method for the determination of quantity and enthalpy ofcombustion air is given in Appendix B to cover cases where quantityof air is not directly measured.