Common faults of SMC regulating valve and its influencing factors 1, jam Frequent problems in SMC regulating valves during jamming often occur during newly commissioned systems and during overhaul. This is because the internal welding slag, iron filings and other impurities in the pipeline gather at the orifice and the guiding portion to cause clogging. After the jam occurs, the medium will not flow smoothly or the filler of the SMC regulating valve will be too tight during the overhaul, which will make the friction become larger, resulting in the phenomenon that the small signal does not move and the large signal moves too much. 2, SMC regulator valve leakage SMC regulator valve leaks typically include leaks due to internal leaks, packing leaks, and deformation of the valve plug and seat. (1) The valve leaks because the length of the valve stem is not suitable. The length of the valve stem of the gas-opening valve is too long, so that the distance between the valve stem is too short or too short, resulting in a gap between the valve core and the valve seat. Contact, resulting in leakage inside the valve. (2) The packing leaks and the packing is loaded into the stuffing box to apply axial pressure to the SMC regulating valve. Due to the plastic deformation of the filler, radial pressure is generated, which is in close contact with the valve stem, but the contact is uneven. During the operation of the SMC regulator valve, axial movement of the stem and packing occurs. In the environment of high temperature and high pressure, it is easy to cause leakage of the filler due to the influence of the high permeability fluid medium. (3) The valve core and the valve seat are deformed, leaked, eroded and impacted, and deformed. As time goes by, the valve core and the valve seat will not match. There is a gap between them, and the gap is not tight. A leak has occurred. 3, SMC regulating valve oscillation The reason for the oscillation of the SMC regulating valve is that the spring stiffness of the SMC regulating valve is insufficient, the output signal of the SMC regulating valve is unstable, and the frequency is sharply changed, the frequency of the SMC regulating valve is the same as the frequency of the system, and the pipe and the base are vibrated violently. There is also an improper selection of the SMC regulating valve. When the SMC regulating valve is operated at a small opening degree, it produces severe flow resistance, flow rate and pressure changes. When this change exceeds the stiffness of the SMC regulating valve, the stability of the SMC regulating valve is made. Reduced, in severe cases, the SMC regulator valve oscillates. 4, SMC regulating valve does not work The failure phenomenon of the SMC regulating valve not working includes: (1) No signal, no gas source. The cause is that the gas source is not open or the gas source is faulty, the air duct is blocked or the pressure reducing valve is broken due to the blockage, and the compressor has a fault light; (2) There is a gas source and no signal. The cause is that the positioner malfunctions due to a leak of the bellows, or the converter fails; (3) The positioner has no air source. The cause is that the filter and the pressure reducer are blocked and fail; (4) The positioner has a gas source but no output. The cause is that there is a blockage in the locator orifice and a failure occurs; (5) There is a signal, no action. The cause is that the spool is detached; the stem is bent or broken. 5, SMC regulating valve is unstable The reasons for the instability of the SMC regulator are: (1) The compressor capacity is too small, causing the pressure reducing valve to malfunction, resulting in unstable gas source pressure; (2) The regulator is unstable, and the time constant of the control system is not suitable, thereby causing signal pressure instability; (3) The frictional resistance of the valve stem during the movement is very large, and a retardation occurs during the contact; (4) The ball valve of the amplifier in the positioner is not tightly damaged by the dirt, and the output oscillation occurs when the air consumption is particularly increased. Common faults of SMC regulating valve and its influencing factors
Casing is a large-diameter pipe that serves as the structural retainer for the walls of oil and gas wells or wellbore.
It is inserted into a well bore and cemented in place to protect both subsurface formations and the wellbore from collapsing and to allow
drilling fluid to circulate and extraction to take place
The oil casing is a steel pipe used to support the well wall of oil and gas wells to ensure the normal operation of the whole well during drilling and after well completion. Several layers of casing shall be used for each well according to different drilling depth and geological conditions. Cement shall be used for cementing after casing is put into the well. It is different from TUBING and drill pipe and cannot be reused. It is a disposable consumable material. Therefore, casing consumption accounts for more than 70% of all oil well pipes.
Casing is a large-diameter pipe that serves as the structural retainer for the walls of oil and gas wells, or wellbore. It is inserted into a well bore and cemented in place to protect both subsurface formations and the wellbore from collapsing and to allow drilling fluid to circulate and extraction to take place.
Surface casing
- Protects the well from contamination in shallow water and gas layers.
- Supports the wellhead equipment and sustains the weight of the other layers of casing.
Intermediate casing
- Isolates different layers of pressure to facilitate normal circulation of drilling fluid and protect the production casing.
- Intermediate casing facilitates the installation of blow-out preventers, anti-leakage devices and tailpipes in the well.
Production casing (oil string)
- It is the conduit through which oil and gas pass from a below surface reservoir.
- It protects the well and separates fluids into various layers.
First, green pipes are threaded on each end. The threading is then inspected and, if necessary, rethreaded to ensure that the thread accurately connects to the coupling. The threading type includes STC/BTC/LTC. The casing pipes are strengthened by surface treatment and are subject to various inspections, including drifting and hydrostatic tests before they are coated and packaged into casing.
Casing pipes are ordinarily produced with outside diameter sizes of 114.3 mm to 508.0 mm.
Casing,Api 5Ct Casing,Api Spec 5Ct Casing PipeApi 5Ct Pipe Oil Casing ESASTSUN OILFIELD EQUIPMENT MANUFACTURING (CAMBODIA) CO., LTD , https://www.eastsuncambodia.com