ASME PTC 12.1-2015 pdf free

ASME PTC 12.1-2015 pdf free.Closed Feedwater Heaters Performance Test Codes.
(a) For the purpose of this Code, a closed feedwater heater is a power plant heat exchanger designed to heat a given quantity of feedwater through a specified ternpcrature range. The heating medium is steam or condensate at a specified temperature and pressure. In Ieedwater heaters, the feedwater and heating medium typically are routed through the tubes and shell, respectively. Feedwater heaters are typically designed to be configured in one of the following ways:
(1) horizontal
(2) vertical channel down
(3) vertical channel up
(4) duplex (two separate tube bundles in a single divided shell)
(h) In some cases, more than one feedwater heater is required for a given fcedwater flow and extraction steam source. In such instances, the leedwater heater is divided into two or three parallel heaters, which constitute a multiple string arrangement.
The shell side of the heater may be constructed with one, two, or three independent zones and arranged in various combinations:
(1) desuperheating zone
(2) condensing zone
(3) drain cooling zone
Each zone is considered to be an independent heat transfer entity contained within the same shell.
Extraction steam from the turbine is the heating medium in the desuperheating zone. Depending on the heater design, extraction steam from the turbine together with other possible energy sources such as incoming drains are the heating medium in the condensing zone. Condensate is the heating medium in the drain cooling zone.
(C) This Code is written in accordance with the ASME PTC 1, General Instructions. ASME PTC 2, Definitions and Values, defines certain technical terms and numerical constants which are used in this Code with the significance and value therein established. The PTC 19 Series, Supplements on Instruments and Apparatus, which covers the instruments prescribed in this Code, should be used for reference.
1-2 OBJECT
The object of this Code is to provide the procedures, direction, and guidance for determining the thermohydraulic performance of a closed feedwater heater. It can be utilized to verily contractual performance for a new heater or to calculate performance of an existing heater in comparison to the design point. The overall performance parameters utilized to accomplish this are the following:
(a) terminal temperature difference T1D), which is the difference between the saturation temperature corresponding to the steam inlet pressure and the fcedwater outlet temperature
(b) drain cooler approach (DCA), which is the difference between drain outlet temperature and feedwater inlet temperature
(C) tube-side (feedwater) pressure loss through the heater
(d) shell-side pressure loss through the desuperheating zone
(e) shell-side pressure loss through the drain cooling zone
The Code methodology adjusts the manufacturer’s guaranteed performance parameters to the actual test conditions, for a comparison to as-tested performance.
1-3 SCOPE
This Code applies to all horizontal and vertical heaters except those with partial pass full-length drain cooling zones. The heater design is based on a specific operating condition that includes flow, temperature, and pressure. This specific condition constitutes the design point that is found on the manufacturer’s feedwater heater specification sheet.
Generally, it is not possible to conduct the test at the exact design point. Therefore, it is necessary to predict the heater performance by adjusting the design parameters for the actual test conditions. Methods of calculating the predicted heater performance are presented in this Code. These predicted values shall then be compared to corresponding measured test values.ASME PTC 12.1 pdf free download.