What Kind of End Connection Should Be Selected for Control Valve?

There are differential end connection for control valve end connection , such as  flange connection, threaded, or even welded end. Flange connection is the most common control valve end connection in the oil & gas application. Other connection such as threaded or welded end is only used in particular application.

The type of  control valve end connection shall refer to any project specification or a piping class data sheet. In general , if  valve size is over  2”, it shall have a flange connection, threaded connection is acceptable for 2” and below. Welded end control valve connection is rarely used except for an application that requires no leakage in the connection between valve and pipe line or any pipe stress consideration.

The connection between flange and valve body are preferably used an integral body flange casting. It means the control valve body and a flange, casting together so that there is no welding requirement to joint the valve and the flange.

In case the sleeve control valve factory couldn’t have an integral body flange casting, as a rule of thumb used a weld neck flange that require a butt weld or full penetration weld to connect flange and valve body. Later on, this weld will require a NDE (Non Destructive Examination) Radiographic Test.

Slip on flange that use a fillet weld shall not be used because fillet weld is weaker than butt welded. Socket weld flange that use fillet weld may be used for valve 1 ½ inch and below. Even though socket weld flange also use fillet weld, but the internal weld of this flange increase the fatigue strength more than the slip on flange.

This flange is allowable for small size of control valve end connection due to difficulties of but weld perform in such size. All fillet weld connection will require a Magnetic Particle Examination or Liquid Penetrant Test.

There are three types of flange facing that will be used in the valve end connection as follow:

1. Flat Face Flange (FF Flange) :

These are used for low pressure or low valve class such as class 150 for control valve

2. Raised Face Flange (RF Flange) :

These are used for control valve class such as class 300 and class 600.

3. Ring Type Join Flange (RTJ Flange) :

These are used for high  class such as class 900 and above.

How to Properly Select and Maintain Vortex Flow Meters

Vortex flow meteris mainly used for flow measurement of industrial piping media such as gas, liquid, steam and other media. It is characterized by small pressure loss, large range and high accuracy, and is almost independent of fluid density, pressure, temperature and other parameters in the measurement of working condition volume flow. No movable mechanical parts, so high reliability and low maintenance. The vortex gas flow meter parameters are stable over time. The instrument adopts piezoelectric stress sensor with high reliability and can work in the operating temperature range of -25 ℃ ~ 320 ℃. There is an analog standard signal, but also digital pulse signal output, easy to use with computer digital system, is a relatively advanced, ideal flow meter. 

 1)Vortex gas oil flowmeter instrumentation is not suitable for installation in the strong vibration of the occasion is widely known to the applicant, but in the occasion of frequent changes in the magnetic field, vortex air flowmeter  will be measured above the normal value of the signal output. It has been proven that in a gas-free field, when the vortex liquid flow sensor is in a changing magnetic field, the vortex flow sensor will sense an error signal at the moment of magnetic field change and output a normal signal when the change ends and the meter is in a stable magnetic field.　　

2) Coke oven gas will have moisture in the gas transmission process due to the high temperature and high humidity at the factory. The gas flow drives the water back and forth, thus creating a pulsating flow. Vortex air flowmeterin this fluid state when the output data is large or small control engineering network copyright, simply do not reflect the production conditions.　　

3) Due to the coke oven gas more impurities, easy to crystallize, impurities condensed in the sensing head, resulting in measurement misalignment. As the temperature rises, impurities evaporate, sensitivity increases and the signal is enhanced; conversely, it decreases. This creates data instability.　　

4) The vortex flowmeter wiring process is inaccurate, resulting in intermittent signals during transmission.　　

5) The vortex flowmeterground wire does not meet the specification requirements, so that the strong power in the 50Hz interference into, when the normal signal is higher than 50Hz output normal signal, the reverse will output the wrong signal.　

How to maintain　

1) In the vortex flow meter installation, connection process, should ensure the accuracy of each link, including the pre-installation inspection of the site, the installation process of the instrument wiring, system grounding wire and other aspects of the control engineering network copyright, so as to ensure the detection of real data and accurate output.　　　

2) For the operation of the metering system can be used "double gui metering control engineering network copyright, comparison confirmation" method, as well as "alternative method" for the operation of the metering instrument failure confirmation and troubleshooting.　　

3) Periodically clean the  vortex flow meter as a whole, if necessary, blow the sensor head part of the  vortex flow meter to avoid the condensation of impurities at the sensor head. The addition of heat tracing devices to the meter section and the meter section during the cold season is also beneficial in reducing the condensation of impurities at the meter.　　

4) Regular drainage of pipes, especially the moisture in front of the straight pipe section, according to the specific situation, set up a person to discharge regularly, as far as possible to reduce the moisture in the measured pipe section, to maximize the exclusion of pulsations in the fluid.　　

5) Strengthen the vortex flow meter metering system data management, set up timed printing function, based on the print data combined with the production status of the instrument operation analysis.

 The above information is provided by flow instrument manufacturer.

Pneumatic Tri-Eccentric Hard Seal Butterfly Valve Delivery

The disc of the tri-eccentric hard seal butterfly valve is installed in the diameter direction of the pipeline. In the butterfly valve body cylindrical channel, disc shaped disc around the axis of rotation, rotation Angle between 0°~90°, rotation to 90°, the valve is fully open. The characteristics of the new high life stainless steel butterfly valve and the problems in the use of the butterfly valve.

The tri-eccentric hard seal butterfly valve is widely used in metallurgy, electric power, petrochemical industry, water supply and drainage, municipal construction and other industrial pipelines where the medium temperature is no more than 425℃, for regulating the flow and cutting off the fluid.

 

Pneumatic tri-eccentric hard seal butterfly valve is based on the two -eccentric hard seal butterfly valve to generate an angle (the sealing surface is an inclined cone), thus forming the tri-eccentric hard seal butterfly valve . The structure has no mechanical wear and scratch in the process of opening and closing , small closing torque , good cutting performance and long service lige , as well as two functions of adjustment and cutting.

This Pneumatic tri-eccentric hard seal butterfly valve is DN800 , for air application , its function for cut-off air course.   It is for one chemical industry in Southeast of China.   

The valve body is WCB , pressure is DIN 0.6 Mpa , working temperature is -60 to 200 °C  

The max size for  Pneumatic tri-eccentric hard seal butterfly valve BCST can make is DN 2000.

If you have any special requirement , we can also make based on your detail.  

Points to Be Noted in Electromagnetic Flowmeter Engineering Application

In the petrochemical, chemical, electric power, metallurgy, municipal, pharmaceutical and other industries, the technical difficulty and complexity of flow measurement are quite high. Research on flow measurement plays an important role in improving product quality, reducing business costs, and solving energy conservation and environmental protection. The electromagnetic flowmeter has the advantages of no resistance and no pressure loss, which can fully reduce the resistance in the pipeline and meet the requirements of energy saving and consumption reduction, so the electromagnetic flowmeter has been widely paid attention in the industry. However, although the electromagnetic flowmeter has the above advantages, and it is much better than most other types of flowmeters in reliability and stability, but in actual use, some problems will occur, the following magnetic flow meter factory will list the main points that need to be paid attention to in the application of electromagnetic flowmeter.

1. The transmitter should be installed at a position where the measurement tube can be filled with liquid at any time to prevent the illusion that the pointer is not at zero because of no liquid in the measurement tube. It is best to install it vertically to reduce the error caused by the liquid flowing through the bubble generated on the electrode. If placed horizontally, the two electrodes of the flowmeter must be kept on the same level, in order to prevent sediment or air on the top of the tube to insulate it.

2. If necessary, the tube can be emptied. The built-in empty tube detection circuit will stop the accumulation and flow signal output.

3. For the fluid flowing in the anode-protected pipeline, the following points should be observed when installing the electromagnetic flowmeter: To make the fluid well grounded, a ground ring should be used; when the sensor is connected to the pipeline, there must be insulation between the flanges Insulation sleeves should also be used on the pads and screws.

4. When the electromagnetic flowmeter is installed on the grounded metal pipeline, the system potential balance is achieved through the grounding terminal on the electromagnetic flowmeter transmitter, that is, the copper core wire with a cross-sectional area of not less than 6mm2 is connected to the grounding terminal; When the electromagnetic flowmeter is installed on an ungrounded metal pipe, the two flanges are connected to the pipe flange through a copper core wire with a cross-sectional area of at least 6mm2 and are grounded. Connect the transmitter or sensor junction box to the ground terminal. Achieve system potential balance; when the electromagnetic flowmeter is installed on a plastic pipe or a pipeline with an insulating lining, the system potential balance is achieved through an additional ground ring, which is connected to the ground terminal through a copper core wire with a cross-sectional area of at least 6 mm2.

3 Way Electric Actuated Control Valve

3 Way Electric Actuated Control Valve

3 Way Electric Actuated Control Valve

3 way electric control valve has two action types: electric mixing(converging) control valve and electric diverting(diverging) control valve.The 3 way electric control valve is composed of PSL series and 3810 series linear electric actuator and 3-way valve body.The electric actuator is an electronic integrated structure with a servo amplifier. The input control signal (4-20mADC or 1-5VDC) and the power supply can control the valve opening to achieve to control the parameters of pressure, flow, liquid level and temperature. The electric 3-way mixing control valve is mainly used for mixing two fluids into a third fluid; the 3 way diverging electric control valve is mainly used for dividing one fluid into two fluids.

If you want to know more detailed information about this product, you can click the link below

https://www.bcstgroup.com/product-electric-actuated-control-valve.html

Body is carbon steel
1	Valve Body	WCB	LCB	WC9
2	Valve Seat	304	304	304
3	Valve Plug	304	304	304
4	Guide Cage	304	304	304
5	Valve Bonnet	WCB	LCB	WC9
6	Valve Stem	304	304	304
7	Packing	PTFE/Flexible graphite
8	Spring	65Mn
9	Nut	304	304	304

Technical Parameter for BCST 3 Way  Electric Actuated Control Valve 

Bonnet Type	standard type(-17～+250℃),high temperature type(+250～+450℃), cryogenic type(-40～-196℃),bellows type(-40～+350℃)
Seal Packing	PTFE, flexible graphite
Plug Type	double guide cage type plug
Flow characteristics	linear,equal percentage
Actuator Type	381L electric actuator,PSL electric actuator,or other specified actuator
Actuator Parameters	voltage:220V/50Hz,input signal:4-20mA or 1-5V·DC,output signal:4-20mA·DC
	Protection level:IP55,Explosion proof:ExdⅡBT4(ExdⅡBT6 customized),hand function: handle.
	Ambient temperature:-25～+70℃;humidity:≤95%.

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3 Way Pneumatic Globe Control Valve

3 Way Pneumatic Globe Control Valve

3 Way Pneumatic Globe Control Valve is equipped with double-seats and cage-guided structure.The valve is divided into 3 way mixing(converging) control valve and 3 way diverting(diverging) control valve.Because the 3 way globe control valve achieves flow mixing temperature rise or temperature reduction, or fluid unequal flow diverting,then it can meet the needs of different working conditions.

BCST are the professional manufacturer for 3 Way Pneumatic Globe Control Valve 

This  three way globe control valve has the advantages of compact structure,light weight, sensitive action,small pressure drop loss,high pressure type,large valve capacity,accurate flow characteristics and convenient maintenance, and can be used in the automation control of various working conditions.This 3 way globe control valve has various forms such as mixing(/diverting) normal type, and mixing(/diverting) high temperature type. 

Technical Parameter for BCST 3 Way Pneumatic Globe Control Valve 

Product Name: 3 Way Pneumatic Globe Control Valve 
Feature:mixing(converging), diverting(diverging);
Nominal diameter:DN25~DN400;
Nominal pressure:PN16,PN25,PN40,PN64,etc;
Flow characteristics:linear,equal percentage;
Material:carbon steel,stainless steel,carbon iron,etc;
Shutoff class:class III,class Ⅳ;
Flange size: Comply with the standard of JB/79.1(2)-94,HG20592 97,GB,ANSI,JIS,DIN;

Operation temperature:Normal temperature:-40+230℃,Medium temperature: +230~+450℃,High temperature:+450~+560℃,Cryogenic temperature:-196~+40℃;
Series type:normal temperature,medium temperature,cryogenic temperature,bellows sealing type,jacket insulation type,regulating shut-off type.

Structure for BCST Pneumatic Globe Control Valve 

PartsName	Material
Valve Body	WCB、304、316、WC6、WC9、Ti、Ni、Hastelloy、Monel,etc
Valve Plug & Valve Seat	304、316、WC6、WC9、Ti、Ni、Hastelloy、Monel,etc
Valve Stem	0Cr18Ni9、2Cr13
Push Rod	0Cr18Ni9、2Cr13
Spring	60Si2Mn
Bellows	0Cr18Ni9
Diaphragm	Clip reinforced nylon fabric nitrile rubber
Diaphragm Cover	A3、0Cr18Ni9
Gasket	0Cr18Ni9、graphite wound gasket(V6590)、F4
Packing	PTFE  ,  Flexible graphite

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https://www.bcstgroup.com/