1. How do I size a VPVL actuator if I only have 40 PSI air pressure?
2. What are the power requirements of Rexa Electraulic actuators

1. What is a full bore valve?
2. What is a reduced bore valve?
3. What is the pressure loss difference between a Full Bore and a Reduced Bore valve?
4. How does the Jamesbury Lip Seal design work?

1. How to Size a Mag Meter?

1. What feature do all converters have?

1. What is AS-i Link?
2. What are some features of AS-i?
3. Can you give some specifications for AS-i?
4. What gateways and interfaces are currently available?

1. What applications suit Vortex Shedding flowmeters?
2. What are the benefits of Vortext Shedding flowmeters?
3. What sizes of vortex meters are available?
4. How does a vortex meter work?

Actuator Frequently Asked Questions

If you have only 40 psi and you would like to apply a VP-VL spring return actuator, the most effective spring combination is three springs on each piston. This designation is SR3. The easiest approach is to take standard 60 psi ( SR 4/5 ) unit from stock and remove one spring from the piston that has four springs and then remove two springs from the piston that has five springs. Having done this you will have three springs remaining on each piston ( SR3 ). The torque output for SR3 actuators running at 40 psi is in the table below.

If you would like further assistance in actuator sizing, please contact Summit Controls.

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The power requirements depend on the power module of the actuator. Here is a list of modules and their power requirements:

• Single B-pump Power Module: 120 VAC, 4 amp
• Single C-pump Power Module: 120 VAC, 8.5 amp
• Dual C-pump Power Module: 120 VAC, 15 amp
• Single 1/4D-pump Power Module: 120 VAC, 10 amp
• Single 1/2D-pump Power Module: 120 VAC, 10 amp
• Single D-pump Power Module: 240 VAC, 10 amp
• Dual D-pump power Module: 240 VAC, 20 amp

Ball Valve Frequently Asked Questions (FAQ)

A full bore (or full port) valve is one where the hole in the ball is equal in diameter to the hole in the pipe. In other words, if you were to look down a piece of pipe which also contained the valve, you would not notice any constriction at the location of the valve.

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A reduced bore ( also called a standard bore or port) valve is one where the hole through the ball is smaller than the hole in the pipe. In some valves such as the Jamesbury 5000 series, there is a gradual narrowing so that the valve almost looks like a vena contracta. In other valves, such as the reduced bore Jamesbury 4000 series, the reduction is simply a shoulder.

Often, the reduction in diameter is to the next standard size. For example, a 2" (nominal size) reduced bore valve would have a 1.5" bore in the ball. A 1.5" (nominal size) reduced bore valve would have a 1.25" bore in the ball and so on. This comes from a rule of thumb which actually coined the term "standard bore" as much as the desire for modular design to allow the same ball to be used in one size of full bore valve and another of a standard bore. Long time ago, the engineers noticed that to get good control, very often the solution was to use a full bore valve of one size smaller than the pipe you were using. Now, this arrangement required reducers on either end of the valve. Someone then came up with the idea of integrating the reducers in to the valve and the standard bore valve was born.

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Engineers as well as pipe designers feel that because of the restriction in a reduced bore ball valve, that a significant amount of pressure loss happens. Actually, it is less than one might think. We will use Neles Automation's valve sizing program Nelprof© to demonstrate how little difference there actually is. The conditions we will use are as follows:

• Flow rate: 150 gpm
• Upstream Pressure: 50 psig
• Temperature: 75F

We will adjust the differential pressure until the valve is showing as close to 100% open as possible. Here is the sizing of the full bore valve:

Using the same process data, we will size a reduced bore valve.

The difference is less than a tenth of a psi. Granted that the reduced bore valve has a pressure loss that is about an order of magnitude greater, either case becomes insignificant when compared to the pump output. For the savings available from using the reduced bore valves, it should be considered.

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Jamesbury's lip seal deisgn uses a completely different sealing principle than a typical "Jam" seat. A "jam" seat is simply jammed between the body and the ball and uses the compression of assembly to provide the forces necessary to create a seal. This results in high operating torques and thermal expansion problems.

With Jamesbury's Lip seal design, the ball is cradled between the two seats but the seal is created by elastic (spring-like) movement of the seat's lip rather than compression of the complete seat. The movement of the lip is limited by the heel. Once the ball has moved a pre-determined amount against the lip due to pressure or thermal expansion, the ball then contacts the heel and significantly reduces any subsequent movement. The benefits of this design include cavity relief without a relief hole or upstream pressure. Also, it reduces the operating torque requirements for the valve. Finally, the design copes much better with thermal expansion than a typical "jam" seat.

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The optimum flow velocity for normal service should be approximately 10 ft/s at max flow. Use the following steps to verify that you have chosen the correct size:

1. For normal service at 10 ft/s, pick a meter size that will measure equal to or greater than your maximum flowrate ( See footnote 1 ). Refer to table below.
2. For slurries, pick a meter size that gives one of the following velocity ranges depending on your meter type:
   • Abrasive Slurry = 3 - 8 ft/s
   • Non-abrasive slurry = 9 - 15 ft/s
3. To verify the appropriateness of your selection, calculate the flow velocity as shown in the following example:
   • Abrasive Slurry
   • Process Pipe Size: 3"
   • Desired max flow rate: 175 USGPM

From the table, obtain the velocity at 40 ft/s for 3 " meter (955.6).

v = 7.32 ft/s
A 3" meter is the appropriate selection since v < 8ft/s

Footnotes:
1. Due to the rangeability of magmeter technology, max flow rates of either less than or more than 10 ft/s are acceptable. Magmeters are often sized to match line size. When selecting a magmeter, keep in mind that measurement accuracy begins to deteriorate at velocities below 1 ft/ s. If you find that your desired flow rate is close to 1 ft/s, consider using a smaller flowmeter. When reducing piping, concentric reductions must be used.

2 Full scale analog output may be set between 1 and 40 ft/s.

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Converters

All Converters have the following features:

• Microprocessor signal conditioning for fast and stable dynamic response
• Display forward and reverse flowrate and total, including the net integrated total
• Back-lit LCD display
• Aluminum housing with polyurethane finish (IFC 010 and IFC 020 have polycarbonate convers)
• Minimum of simultaneous 4-20 mA analog, pulse and status output
• User-friendly keypad for easy configuration via menu-driven display (when converter has display)
• HART smart communications option (except IFC 010)
• IFC 010 - DC-Powered for Battery Mobile Operation: Remote or integral for basic applications, 11-32 VDC, with display, 0.5% accuracy, 4-20 mA, pulse and status output.
• IFC 020 - HART Smart for General Applications: Remote, Integral or rack mount for most applications. 110-220 VAC, with display and HART or RS485 communications, 0.3% accuracy, 4-20 mA, pulse and status output.
• IFC 090 - HART Smart for Industrial Applications: Remote or integral universal converter, handles slurries or pulsating flow, 0.3% accuracy, blind or with display, HART communications, general purpoer or FM/CSA Class I, Div 2; 24 VAC/CDV or 110 - 220 VAC, 4-20 mA, pulse and status output, ontrol input. May be configured with various output combinations.
• IFC 110 Remote - HART Smart for Difficult Noisy Flows: Remote universal converter, handles slurries or pulsating flow, 0.3% accuracy, (0.2% is optional); displat with HART and RS485 communcations, 24VAC/VDC or 110 - 220 VAC, 4-20 mA, pulse and 4 status outputs, 2 control inputs. May be configured with various output combinations. Upgradeable electronics.
• IFC 110 PF - Tidalflux Converter: Remote for Tidalflux, handles partially filled pipes. 1.0% accuracy, display with HART communications and internal level indication, 110-220 VAC, 4-20 mA, pulse and 4 status output, 2 control inputs. May be configured with various output combinations.

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AS-i Link Frequently Asked Questions

It is a field proven standard for discrete (On/Off) actuators and sensors and stands for Actuator Sensor Interface. Although more complex netwoeks may be used in this role, AS-i is optimally suited for this level. Because of its proven reliability, wide range of bus interfaces and huge installed base, it is well accepted throughout the world at this level.
Proven benefits include: Installation cost savings of over 35%; dramatic wiring and I/O space reduction; field devices easily added or removed; simple structure allows for easy installation and operation; ease of comprehending.

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• Ideally suited for on/off batch process valves and other discrete applications
• 31 field devices per network master
• Simple electronics for economical and robust performance
• Transfer medium unshielded two-wire cable for both data and power supply
• Signal transmission has high tolerance to EMI
• Easy to install providing the greated cost savings with least complexity
• Free choice of network topology allows for optimized wiring network
• Variety of gateways available to seamlessly tie into high level bus networks

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3. Can you give some specifications for AS-i?

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Currently, Stone-L offers the following connectivity options:

• Modbus (RS232C, RS422, RS485)
• Modbus+
• Profibus (DP, FMS)
• DeviceNet
• CAN
• Interbus-S

In addtion, an ISA card is available for your PC to connect as the master for a group of devices.

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What field wiring components are available to help implement a fieldbus networking system?

Vortex Shedding Flowmeter Frquently Asked Questions

1. What applications suit Vortex Shedding flowmeters?

The vortex shedding meter is best used for gas and steam, as well as liquids of low viscosity that do not contain significant amounts of solids. In fact, steam is the largest single application for vortex meters. The vortex meter can be used in most applications where dP/orifice meters have been used.

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2. What are the benefits of Vortext Shedding flowmeters?

• Accuracy: The vortex meter accuracy is +/- 1% of measured flow over a wide range of flows.
• Versatility: The same meter can be used for liquid, gas or steam.
• Low Pressure Drop: The pressure drop is typically less than for comparable flows using orifice plates. For example, for a flow of 150 gpm of water in a 2" vortex meter, the pressure drop would be 3.3 psi while in a 2" line using an orifice plate, the pressure drop would be 11.2 psi.
• Rangeability: The meter rangeability is very high, up to 45:1 is possible.
• Lower Cost: The installed cost of a vortex meter is more attractive than a differential pressure meter system up through to 6" size. The installed cost considers all the components required as well as the labour on site to put them together.
• Ease of Installation
• Higher temperatures up to 800 F are possible

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3. What sizes of vortex meters are available?

Sizes range from 3/4" to 12". They are available in flanged and wafer styles.

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4. How does a vortex meter work?

The basic concept is that there is a flow obstruction, or shedder, that causes the flow to separate and then shed swirls or vortexes of flow. The rate at which the swirls are shed is directly proportional to the amount of flow passing the shedder. However, one should note that at very low densities flowing slowly there is very little energy in each vortex swirl. At some point in the flow range the energy is too low for the sensor to detect and the meter goes to zero. For liquids, the lower limit of the operating range is determined by the Reynolds number of the flow. The Reynolds number (Re) is viscosity dependant and as the viscosity goes up, the Re goes down. Vortex meters are linear in output to an Re of 20,000. Below that, the vortex shedding process starts becoming less regular until is becomes so irregular that it is unreliable. For optimum performance in a vortex meter, the viscosity of the liquid should be water-like.

As the flow strikes the shedder located in the middle of the flow stream, the flow must separate to go around the shedder. As it does, it rolls up in swirls or vortexes on alternating sides of the shedder. The vortex swirl hangs on the shedder growing larger until its volume gets too large at which point it separates or sheds from the shedder. At the point of shedding there is a momentary low pressure, high velocity on one side and a momentary high pressure, low velocity on the other side. The next vortex swirl then forms on the opposite side and repeats the process all over again. The vortex swirls are always shed on opposidte sides of the shedder, 80 degrees out of phase with each other. Each vortex swirl grows to be the same size so you can determine a K-factor to express the ratio of swirls to volumetric flow regardless of what the flowing material is. Using this K-factor and counting the number of pulses, you can determine total flow or volumetric flowrate and the meter then outputs this information on a 4-20 mA signal.

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