Bailey Valves Inc. | Focused Water Solutions

B–12

Introduction

The Bailey Valve model B-12 sleeve valve has been designed to incorporate features that provide superior valve performance for angle flow control, pump control, tank level control, metering vaults, reservoirs discharge and ground water recharge. The Bailey models B-12 valve dissipates energy and controls flow by diverting the water path arounda sleeve and into a valve body. The valve modulates flow by sliding a pipe called. the sleeve through a seat ring. The sleeve is designed with multiple sized and spaced tapered nozzles for each specific project. This design controls cavitation by directing damaging implosions away from any metallic surfaces, thus reducing vibrations and noise normally associated with modulating valves. The nozzles are placed within the sleeve in a helical pattern that allows for specifically desired incremental volume change with movement of the gate. Each sleeve nozzle configuration is designed for the application needs to produce superior flow pressure control over the entire requested flow range. Flow passes through tapered nozzles in the sleeve and energy is dissipated during a mixing process in the center of the valve prior to exiting the valve body. The advance and retract movement of the gate is accomplished through one (1) drive screw or hydraulic cylinder located on the top of the valve. The bailey Valve model B - 1 2 i s capable of flowing from 500 GPM to over 380,000 GPM

Sizes

8” (200mm) through 72” (1830mm)

Pressure Class

ANSI B16.5
Class 150 => 250 PSI
Class 300 => 640 PSI
Class 600 => 1000 PSI

Product Category

Angle - 90 Degree w/ Pipe Discharge

Offers 1:1 Stroke To Diameter Ratio:

Provides better Flow control over short stroke configuration by increasing the sleeve nozzle spacing Reduces the risk of oscillating the gate on the seat under low flow and high delta P condition Allows for more cavitation dissipation inside valve compared to shorter stroke valves Reduces vibration by spreading discharge energy over broader range compared to shorter stroke valves High flow turndown allows the use of one valve in lieu of multiple parallel valves and eliminates oscillation off the seat for most applications.

Satellite Hardfaced Gate:

Provides superior hard surface edge to reduce high velocity erosion of the gate.
Creates dissimilar hardness in non-bound mating materials.
Provides gate leading edge hardness sufficient to shear debris within the nozzle.

Custom Valve Configuration:

Allows for flange matching between valve and associated piping.
Multiple access options.
Valve material options (Carbon Steel, Stainless Steel)

Actuation Configurations:

Electric Motor Operated.
Oil Hydraulic Operated w/ Hydraulic Power unit.
Water hydraulic from pipeline pressure.

Model B-12 Sleeve Valve Sizing:

Once the Bailey valve configuration (Inline, Y-Pattern, submerged, angle or non-modulating) has been selected, the next step in choosing the best solution for the application is sizing the valve for the operating conditions. This is first done by collecting key data, which will be used to determine the severity of cavitation as indicated by the cavitation index sigma (σ) velocity flow and flow capacities(Cv).

Step 1

Maximum Flow Rate > Qmax
Inlet Pressure at Qmax > Pi @ Qmax
Outlet Pressure at Qmax > Po @ Qmax
Minimum Flow Rate > Qmin
Inlet Pressure at Qmin > Pi @ Qmin
Outlet Pressure at Qmin > Po @ Qmin

Step 2 - Sigma

The sigma value or cavitation index is calculated and used to configure the performance class of sleeve valve or to determine if alternate options such as ball valves or butterfly valves are acceptable for the application conditions. The following equation is used to calculate the sigma value:

σ = Po - Pv / Pi - Po

Where:
Pi = Inlet Pressure (psig)
Po = Outlet Pressure (psig)
Pv = Vapor Pressure (-14.6 psig for 60°F water at sea level)

Step 3 - Velocity Flow

The maximum flow rate (Qmax) is compared to the figure in the following sample table to determine the corresponding valve size based on an allowable continuous velocity of 30ft/s through the valve port. Higher velocities can be attained for intermittent operating conditions and it is recommended that you contact the factory for sizing. Your flow rate should be rounded up to the nearest table value and record the corresponding valve size. Various units are provided for simplicity.

Step 4 - Flow Capacities (Cv)

The maximum flow rate (Qmax) and associated inlet pressure (Pi) and outlet pressure (Po) are used to calculate the required Flow Capacity of Cv of the application. The Cv equation is as follows:

Cv = Q / (Pi - Po)

Once the application Cv is calculated from the above equation a safety factor of 20% is added to the value for valve Cv deviation and potentional nozzle fouling from entrapped debris within the flow media. The Cv plus 20% value (C20) is compared to the following table to determine the appropriate value size for the application. The chosen valve size must have a higher capacity than the C20 calculated form the operationg conditions. The valve size chosen from the Cv table is then compared to the value size chosen from the previous table (Velocity Flow) and the larger of the two valves is the correct size for the application coditions.