Modern industrial equipment process request centrifugal pumps basically work under condition of variable flow. An automatic recirculation valve (ARC valve) is a multifunctional valve whose primary purpose is to ensure that a pre-determined minimum flow is assured through a centrifugal pump at all times.
This is important as centrifugal pumps suffer from overheating and cavitation and can be permanently damaged if they run dry.
ARC Series
Through many years of research and development, continuous innovation and practice, Elite Flow Control research ARC Series Automatic recirculation control valve, to prevent overheating, serious noise, unstable and erosion damage of centrifugal pump under low load operation.
As long as the flow rate of the pump valve is below a certain valve, the bypass backflow mouth will automatically open to ensure the necessary minimum flow of the pump.
Applications
- Chemical Industry
- Petrochemical Industry
- Steel Factories
- Fire Protection System
- Traditional Power Plant
- Ship Building Industry
- Paper-making Industry
- Environmental Protection
ED Series – Automatic Recirculation Control Valves
ED Series Automatic Recirculation Valves (ARC valves) are suitable for bypass with high-pressure differential, a maximum pressure differential is 30MPa, and the specific choice is determined by the factory. Multistage decompression type M type bypass can eliminate noise made by high-speed flow medium, prevent damage of cavitation erosion and braising to valve components.
Automatic Recirculation Valve Working Principle
According to the difference of inductive main flow, the main valve disc check cone of the Automatic recirculation valve will automatically move to a certain position. At the same time, the main valve disc drives the bypass valve stem, transfers the movement of the main valve disc to bypass, through control bypass valve disc position, changes the bypass throttling area, so as to control bypass flow. When the main valve disc back into the valve seat closed, all flow backflow through the bypass. When the valve discs rise to the top position, the bypass is fully closed, all the flow of pump flow to the processing system.
This valve set four functions in one body:
- Flow perception: Automatic recirculation valve main valve disc can automatically perceive the main flow of the processing system, thereby according to the flow to determine the position of the main valve disc and bypass disc.
- Recirculation control: Automatic recirculation valve can inhaled pump normal operation required minimum flow into storage device through the bypass, so as to adjust pump H – Q characteristics, to realize recycling.
- Bypass multistage pressure reducing: bypass control system can reduce the backflow medium from the high-pressure pump outlet to appropriate backflow to the low-pressure storage device with low noise small wear.
- Check: The automatic recirculation valve also has a check valve effect, preventing the liquid backflow to the pump body. Bypass non-return function is standard.
- A special bypass size can be customized. The max flow rate of the bypass is subject to the max Kv value.
Back Pressure Valves
| Model | EB7 |
| Size | 1” to 6” |
| Set Pressure | PN10~PN400（ANSI 150Lbs~ANSI 2500Lbs |
| Connection | Flange connection standard is according to DIN or ANSI, another standard |
How Do Back Pressure Valves Work?
This valve is self-support type, do axial movement along with valve disc by spring force function, so as to generate differential pressure around the back pressure valve. Meanwhile, the valve seat hole opening bigger and bigger gradually until pressure differential reaches the setting point.
Installation
In order to make the valve achieve to the best performance, BPV should be installed in downstream of the important protected valve, since valve outlet velocity is high, the installation location should be close deaerator or water supply tank.
Maintenance
Be easy to operation and maintenance. We can provide installation and maintenance manuals.
How Do A Back Pressure Valves Install?
In order to make the valve to achieve best performance, YB7 should be installed in the downstream of the protected valve, since valve outlet velocity flow is high, installation location should near close to deaerator or tank.
Installation Location Chart
EB7
Drawing
Material Temperature Range
| Body material Sealing material |
A105 | LF2 | F304 | F316 |
|---|---|---|---|---|
| NBR | -20～+100 | -30～+100 | -30～+100 | -30～+100 |
| FKM | -20～+200 | -40～+200 | -40～+200 | -40～+200 |
| PTFE | -20～+230 | -40～+230 | -80～+230 | -80～+230 |
| Stainless steel gasket | -20～+300 | -40～+300 | -196～+300 | -196～+300 |
Model Selection
| EB | 7 | Nominal Pressure | Body Material | Nominal Diameter | Structure Type |
| Back Pressure Valve | 7 series | PN16=PN16 Class 150LB =CL150 |
C=A105 LC=LF2 P=304 PL=304L R=316 RL=316L |
DN50=50 NPS2”=2” |
D=Water type F=Flange connection S = Overflow function |
| For example, 7 series BPV, Class 1500#, the body material is A105, diameter 2″, flange type connection, Model: EB7-PN40-C-50-F |
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Multistage Minimum Flow Control Valve
Electric/Pneumatic
EHD multistage cage control valve used a multilevel cage symmetric sleeve control valve.
It complete control medium velocity within the valve, and greatly reduced noise made by high-pressure gas or steam within the valve, stabile multistage pressure reduces effective prevent liquid cavitation, so it’s the stable control valve used in high-pressure medium performance, customers can also select multi-spring diaphragm mechanism or pneumatic actuators
| Model | EHD |
| Body Type | Direct casting ball-type valve |
| Nominal Diameter | DN20, 25, 32, 40, 50, 65, 80, 100, 200 |
| Nominal Pressure | PN 1.6, 2.5, 4.0, 6.4, 10.0, 16、25Mpa CLASS 150, 300, 600, 900、1500Lb |
| Connection | Flange: FF, RF, RTJ, welding: SW, BW |
| Flange Distance | according to IEC534 |
| Sealing Gasket | Metal with graphite gaskets |
| Packing | V type PTFE, flexible graphite, etc. |
| Bonnet Type | Standard type lengthened (heat dissipation, low temperature, bellows sealing). |
| Actuator | Pneumatic, multi-spring actuator.
Electric: 3810L series, PSL series. |
| Valve Disc type | multistage cage sleeve type. |
| Flow characteristics | Equal Percentage, Linear. |
| Disc Material | Standard material composition and applicable temperature, pressure range, please refer to the appendix. |
EHD
Customized selection
| Body | Type | Direct | Bonnet | Model | Standard, lengthened |
|---|---|---|---|---|---|
| Material | WCB, WC9, 304, 316,etc. | Material | WCB, WC9, 304, 316,etc. | ||
| Disc | Characteristic | Linear, equal percentage, quick opening | Packing | V type PTFE Flexible graphite, below the sealing |
|
| Material | 304, 304+STL/PTFE, 316, 316+STL/PTFE | ||||
| Actuator | Pneumatic | ||||
| Electric | |||||
| Positioner | Electric valve positioner, intelligent digital positioner | ||||
| Accessories | Solenoid valve, valve position feedback device, hand-operated mechanism, lock-up valve, air filter pressure relief device, etc. | ||||
Material and internal structure
Material And Internal Structures
- The above is a standard configuration structure, the valve seat is metal to metal, and we can still provide strengthened trim with stellate alloy coating. For specifically applicable temperatures, we have more reasonable bolts, nuts to choose from.
- PTFE v-shaped ring stem packing is the standard configuration and can also choose flexible graphite.
- Standard body material is carbon steel and stainless steel, and we can still provide various high corrosive-resistance alloy materials.
Body Material: Carbon Steel
| 1 | Seat | 25 | LF2 | F22 |
|---|---|---|---|---|
| 2 | Nut | 25 | 35 | 25Cr2Mo1VA |
| 3 | Stud | 35 | 40MnB | 25Cr2Mo1VA |
| 4 | Gasket | 316+graphite/PTFE | ||
| 5 | Body | 25 | LF2 | F22 |
| 6 | Seat | 304 | 304 | 304 |
| 7 | Stem | 304 | 304 | 304 |
| 8 | Stud | 35 | 40MnB | 25Cr2Mo1VA |
| 9 | Nut | 25 | 35 | 25Cr2Mo1VA |
| 10 | Gasket | 316+graphite/PTFE | ||
| 11 | Packing gasket | 304 | 304 | 304 |
| 12 | Stuffing | PTFE/Flexible graphite | ||
| 13 | Bonnet | 25 | LF2 | F22 |
| 14 | Pressing sleeve | 304 | 304 | 304 |
| 15 | Gland | 25 | LF2 | F22 |
| 16 | Nut | 35 | 40MnB | 25Cr2Mo1VA |
| 17 | Stud | 25 | 35 | 25Cr2Mo1VA |
Body Material: Stainless Steel
| 1 | Sest | CF8 | CF8M | CF3M | |
|---|---|---|---|---|---|
| 2 | Nut | 304 | 316 | 316L | |
| 3 | Stud | 304 | 316 | 316L | |
| 4 | Gasket | 316+graphite/PTFE | |||
| 5 | Body | CF8 | CF8M | CF3M | |
| 6 | Seat | 304 | 316 | 316L | |
| 7 | Setm | 304 | 316 | 316L | |
| 8 | Stud | 304 | 316 | 316L | |
| 9 | Nut | 304 | 316 | 316L | |
| 10 | Gasket | 316+Graphite/PTFE | |||
| 11 | Stuffing gasket | 304 | 316 | 316L | |
| 12 | Stuffing | PTFE/Flexible graphite | |||
| 13 | Bonnet | CF8 | CF8M | CF3M | |
| 14 | Pressing sleeve | 304 | 316 | 316L | |
| 15 | Gland | CF8 | CF8M | CF3M | |
| 16 | Stud | 304 | 316 | 316L | |
| 17 | Nut | 304 | 316 | 316L | |
