While ultrasonic meters have been used for a number of years to measure gas flow, steam flow is a very new application for them. Magnetic flowmeters cannot be used to measure either gas flow or steam flow. Multivariable differential-pressure flowmeters can be used to measure liquid, gas, and steam.
Modern power plants have huge boilers to feed turbine generators. Use btu/hr (British thermal units/hour) heat input rate to calculate boiler steam flow. If 50 million btu/hr are being applied to the boiler, divide by the 970.28-btu/lb to yield 51,531-lb/hr steam flow.
In the US, steam is conventionally measured in pounds per hour. When I worked in the UK, boiler production was spoken of in tons per hour. Kg/hr or t/hr for mass flow rate, bar or Pa(MPa more usually) for pressure. For other SI units for steam, consult steam tables such as those provided by Spirax Sarco.
By a steam flowmeter
The use of a steam flowmeter may be used to directly measure the steam usage of an operational item of plant. This may be used to monitor the results of energy saving schemes and to compare the efficiency of one item of plant with another.Steam tables are defined as the thermodynamic data that contain the properties of water or steam. These data are commonly used by engineers and architects. It is normally used to obtain the following properties using steam pressure for saturated steam temperature and saturated temperature for saturated steam pressure.
Steam flow measurement accounts for a large proportion of the flow measurement industry. There are seven different models of flow meters alone to measure steam flow. Steam is a source of power and is used widely by a number of industries; its main usage being in process plants and power generation.
Enthalpy of saturated steam, or total heat of saturated steam. This is the total energy in saturated steam, and is simply the sum of the enthalpy of water and the enthalpy of evaporation. hg = hf + hfg. hg = Total enthalpy of saturated steam (Total heat) (kJ/kg)
Measurement. Streamflow is measured as an amount of water passing through a specific point over time. The units used in the United States are cubic feet per second, while in majority of other countries cubic meters per second are utilized. One cubic foot is equal to 0.028 cubic meters.
The flow rate formula, in general, is Q = A × v, where Q is the flow rate, A is the cross-sectional area at a point in the path of the flow and v is the velocity of the liquid at that point.
Divide the pipe's internal diameter by 2. For example, if the pipe has an internal diameter of 0.1 meters: 0.1 ÷ 2 = 0.05 m This is the pipe's radius. Square this radius: 0.05² = 0.0025 m². Multiply the result by pi, which is approximately 3.142: 0.0025 × 3.142 = 0.007855 m².
Q=Vt Q = V t , where V is the volume and t is the elapsed time. The SI unit for flow rate is m3/s, but a number of other units for Q are in common use. For example, the heart of a resting adult pumps blood at a rate of 5.00 liters per minute (L/min).
Flow rate varies inversely to length, so if you double the length of the pipe while keeping the diameter constant, you'll get roughly half as much water through it per unit of time at constant pressure and temperature.
Metric PVC Pipe
| | Assume Average Pressure. (20-100PSI) About 12f/s flow velocity |
|---|
| 1/2" | .50-.60" | 14 gpm |
| 3/4" | .75-.85" | 23 gpm |
| 1" | 1.00-1.03" | 37 gpm |
| 1.25" | 1.25-1.36" | 62 gpm |
With a radius, for instance, of 0.05 meters, 0.05 ^ 2 = 0.0025. Multiply this answer by the pressure drop across the pipe, measured in pascals. With a pressure drop, for instance, of 80,000 pascals, 0.0025 x 80,000 = 200. Multiply the constant pi by the answer to Step 1: 3.142 x 0.0025 = 0.00785.
Water Flow Capacity in Steel Pipes (sch 40)
| Pipe Size | Maximum Flow (gal/min) | Head Loss (ft/100 ft) |
|---|
| 2" | 45 | 3.9 |
| 2-1/2" | 75 | 4.1 |
| 3" | 130 | 3.9 |
| 4" | 260 | 4.0 |
Pipe Size Chart
| PIPE SCHEDULES WALL THICKNESS (Inches) |
|---|
| Nominal | O.D. Inches | 160 |
|---|
| 10 | 10.750 | 1.125 |
| 11 | 11.750 | |
| 12 | 12.750 | 1.312 |
Pipes for steam systems are commonly manufactured from carbon steel ASTM A106. The same material may be used for condensate lines, although copper tubing is preferred in some industries.
Steam Condensate Lift using an On-Off Control Scheme
The back pressure created by lift is approximately 1 PSIG for every 2 feet of condensate lift. The actual number is 2.31 feet per pound, but 2 feet includes some safety factor and allowance for friction loss.1 pound of steam is equal to 970 BTU (or an easy to remember rule of thumb is 1 pound of steam is equal to 1000 BTU. 1 pound of water is equal to a 16 oz tall boy (by volume)…. when you heat that tall boy hot enough to make steam it expands almost 1700 times its original volume.
Steam cycle parameters with a main steam pressure above 250 bar and temperature above 565 °C and up to 600 °C (main steam) and 620 °C (reheat) are commonly called ultra supercritical (USC); these higher steam conditions can be achieved because of the development of new ferritic materials.
A globe valve used to the throttling of the flowing, but a ball valve possesses a ball in order to close the flow. Globe valves are beneficial for the regulating of the flow, whereas ball valves are well-performed for the flow-controlling without any pressure drops.
Using copper piping on steam boiler supply pipes would be a lot less labor involved, but it causes big problems. Copper pipe expands more than steel pipe. The high-temperature change in a steam system will cause copper pipe and fittings to soften and become weak.
Superheated water is liquid water under pressure at temperatures between the usual boiling point, 100 °C (212 °F) and the critical temperature, 374 °C (705 °F).
Steam temperatures seldom exceed 400–455°C. High-pressure units are smaller for a given capacity, and the initial cost is only slightly greater than for lower pressures.
Steam occurs when water goes above 212 degrees Fahrenheit, which is hotter than water when it is at its stable point. While water boils at 212 F, steam is at a much higher temperature as water turns to vapor.
Stainless steel is often said to be a corrosion-resistant metal. In truth, however, it is not the metal itself that is actually corrosion-resistant. TLV employs the use of stainless steel in many of its steam traps and offers stainless steel options for many other products to meet these needs.
Two principal factors determine pipe sizing in a steam system: 1. The initial pressure at the boiler and the allowable pressure drop of the total system. The total pressure drop in the system should not exceed 20% of the total maximum pressure at the boiler. This includes all drops — line loss, elbows, valves, etc.
I've always understood that black pipe is for gas, while galvanized should be used for anything that is water, such as steam.
No. PEX is plastic and is not rated for steam, which reaches temperatures of 212ºF.
Steam pipe. Steam pipe may refer to: A pipe designed to carry pressurized steam from a boiler to the working components, i.e. the steam engine(s) or turbine(s). Such piping usually includes valves to control the routing of the steam, or to stop the flow altogether.
Drip Legs:
a) Let condensate escape by gravity from the fast moving steam. The properly sized drip leg acts as a separator by providing an increase in flow area, which slows the steam flow down allowing the condensate to drop out. This is important during operation as well as start-up.Condensate lines will contain two phases, condensate (liquid) and flash steam (gas.) Therefore, the correct size of a condensate line is somewhere between a hot water line and a steam line. With proper knowledge, a condensate line may be sized for the following: Condensate liquid load. Flash steam load.
