Finding a boiler feed pump suitable to your boiler system is of utmost importance. Not all boiler feed pumps were created equal; therefore it is essential that you select one tailored to meet your specific industrial requirements in order to maximize its capabilities. Boilers are under-pressure tanks which use heat to vaporize water into steam which has various industrial uses like heating homes and power generation as well as water heating. We offers boiler feed pumps from Hoffman Specialty, Mepco, Shipco and Sterling. Boiler feed pumps transport feedwater used to maintain levels in steam boilers or to convert waste water back into steam; typically centrifugal in design and available with various motor sizes for optimal use.
Boiler systems are complex devices that use various stages to turn water into steam, and one of the first steps during the steaming process is feeding liquid into it. In order to do this, a boiler must have an engine feed pump. Boiler feed pumps pump freshwater directly into steam boilers using high pressure units; some of this condensed water may later be reused via condensate return systems while others are returned via their boiler feed pumps back through again and the cycle repeats itself.
Find out the control method to be used.
Understanding how you control the delivery of feedwater will be instrumental in selecting an appropriate boiler feeder pump. There are two commonly-used control methods for feedwater delivery: on-off control and modulating feedwater control. If using on-off control, an extremely robust boiler feed pump would be needed that can withstand abrupt water surges; with modulating feedwater control this risk becomes significantly reduced.
Calculate the base flow rate.
An average flow rate measures the amount of water that flows out of a faucet in one minute. Boilers require a consistent, uninterrupted feedwater stream, with pressure acting to maintain constant rate of feedwater flow. To accomplish this goal, first identify your base flow rate – use boiler capacities horsepower = 0.069 + C as an effective formula; its value depends on whether your pump operates intermittently or continuously feeding mode and could range anywhere from 1.50-1.15 respectively.
Consider the continuous boiler blowdown flow.
Continuous blowdown is used to flush away total dissolved solids (TDS). This ensures no impurities enter your boiler that could lead to wear and tear over time. Although not necessary, including your continuous blowdown flow in order to determine which boiler feed pump you require – add 10 percent of its efficiency flow rate as a guideline.
Check the bypass flow rate.
If the method you are trying to control involves a bypass recirculation pipeline and valve, you will need to include flow rates from bypass into your calculations of total rate of flow. Certain control methods like Variable Speed Drive (VSD), continuous bypass system or controlled bypass system could alter this figure depending on their control method – these all aim at keeping pump operations below their shutoff point and using minimum operating levels so as not to reach shutoff point too soon. Each bypass flow depends on pump’s requirements; typically 10%-20 percent. As a reminder you should consult manufacturer or technical manual when making changes or calculations involving these variables.
Compute for the total flow rate.
Now that you understand the flow rate of base and other factors such as constant boiler blowdown rate or bypass flow rates, you are able to calculate the total flow rate. This refers to how much water passes through your system during any given duration.
Determine the feed pump’s base head.
Once you have determined your total flow rates, the next step should be establishing the total dynamic head (TDH). TDH represents the entire pressure at which water flows through your system – similar to how you calculated total flow rates. Start with your feed pump’s basic head before moving forward with other calculations.
Determine the shutoff head.
As well as making sure your flow rate is appropriate, it is also necessary to think about your shutoff valve. In order to determine if the head has low flow levels, your safety valve needs to be in the “off” position; once this occurs you can add 3 percent.
Compute for the total dynamic head.
Add all the dimensions for all components of a head, such as its base head, suction side piping head and discharge side piping system head. Be certain that the base head provides safety measures.