Category » Valves

There were 17 articles found in this category:

1. Modeling Circuit Balancing Valves in PIPE-FLO
   Customers who wish to model circuit balancing valves in PIPE-FLO should first obtain the performance curve or CV data for the valve from the valve manufacturer. The performance characteristic curve of flow rate (gpm) vs. head loss (feet of water) for a 4" Bell & Gossett Circuit Setter Plus bala ...
2. Modeling and Troubleshooting Flow Control Valves
   Flow control valves (FCVs) maintain the flow rate in a line to a fixed value and calculate the differential pressure across the control required to regulate the flow rate. When troubleshooting FCV installations, it is helpful to know how PIPE-FLO internally models them. A schematic of how PIPE- ...
3. Specifying Control Valve Data
   If you want to manually set control valves to a particular position, or if you want to know the calculated Cv value at any given position, then you must supply valve performance data to your control valves. There are a couple of ways to specify control valve data. If you have the full range of ...
4. Calculating On/Off Valve dPs
   You can calculate the pressure drop for a specified flow rate through any of the valves & fittings in the Standard Valve & Fitting table. This feature is available for all PIPE-FLO users(except Compressible) and Flow of Fluids users as well as Demo users. The Standard valve & fitting table is u ...
5. Choked Flow Caused by Over-sized or Inappropriate Type of Valve in Liquid Service
   Choked flow is a condition that occurs in a valve when the static pressure of the liquid drops below the vapor pressure, causing the liquid to flash to a vapor. The vapor bubbles occupy more volume than the same mass of liquid, resulting in restriction of the flow through the valve. When fully ...
6. Sending Results to the Control Valve Selection Module
   1. Perform a calculation. 2. While the results are displayed on the FLO-Sheet, select the valve and choose the Tools / Control Valve Selection menu item. The control valve selection module is started and the Open Valve Catalog dialog box is displayed. NOTE: The fluid and pipe data from the va ...
7. Using PSV Files for Control Valve Selection
   Prior to selecting a control valve for an application, the buyer must provide the valve supplier with information on how the valve will operate in the system. This information is typically supplied in paper form. Now with the availability of a Piping System View file, control valve buyers can ...
8. Control Valve Data Import
   Control valve data can be imported from manufacturers' valve selection programs when the programs have export capability. The specific format for valve data is documented in the file CVALVE.XLS which can be downloaded from this article. The recently released Fisher's valve sizing and selection ...
9. Creating a Control Valve Catalog
   With PIPE-FLO's control valve selection module, you can select and evaluate valves from catalogs on disk. Once you have selected a valve, you can import it into your PIPE-FLO model. If a manufacturer's catalog is not available, you can create and edit your own user catalog with the catalog cre ...
10. Sending Data to the Control Valve Selection Module
    1. Select the valve on the FLO-Sheet and choose the Tools / Control Valve Selection menu item. The control valve selection module is started and the Open Valve Catalog dialog box is displayed. NOTE: The fluid and pipe data from the valve's connecting pipelines is automatically sent to the cont ...
11. Modeling and Troubleshooting Pressure Regulating Valves
    The function of a pressure regulating valve is to lower the pressure in a section of the system to a specific downstream set pressure, regardless of the flow through the connecting piping. When troubleshooting PRV installations, it is helpful to know how PIPE-FLO internally models them. A schem ...
12. Modeling and Troubleshooting Back Pressure Valves
    Back Pressure Valves are installed in systems to keep a section of the network above a minimum set pressure. A BPV maintains the set pressure on the high pressure or upstream side of the valve and only allows enough flow through the valve to maintain the upstream BPV set pressure. When trouble ...
13. Modeling a 3-Way Valve
    PIPE-FLO does not have a native 3-way control valve. However, the functionality of a 3-way control valve can be modeled using a combination of two Flow Control Valves. To model a 3-way valve in PIPE-FLO, you can use a combination of two Flow Control Valves (FCVs). The example below will demons ...
14. Modeling Pressure Relief Valve Operation
    Pressure relief valves are used to prevent the overpressurizing of process equipment and piping. They operate automatically at a preset pressure to vent fluid and relieve the overpressure. The following terminology applies to pressure relief valves: Relief valve – primarily for liquid ser ...
15. Modeling Automatic Flow Control Valves
    Automatic flow control valves (AFCV's) are used on HVAC hydronic systems to provide a fixed flow rate of chilled or hot water to various system loads. The proper operation of an HVAC system depends upon a consistent distribution of flow to all loads in the system under design conditions as well ...
16. Modeling a Cv Value as a Component
    If you have a Cv value for a valve or other device, you can model it as a component having a flow rate vs dP profile. Use the equation below to calculate values for the component data table: dP = [(Q/Cv)2]*(rho/62.4) where Q = flow rate in gpm Cv = valve flow coefficient dP = pressure drop in p ...
17. Difference between PRV's and BPV's
    PRVA pressure regulating valve or PRV placed in a piping system regulates the pressure in the system downstream of the PRV to a set pressure. When fluid pressure on the inlet side of the PRV is set greater than the PRV's set pressure, the valve opens to allow fluid to pass through the valve unt ...