Globe valve, also known as cut-off valve, is a mandatory sealing valve, so when the valve is closed, pressure must be applied to the valve disc to force the sealing surface not to leak. When the medium enters the valve from under the valve disc, the resistance that the operating force needs to overcome is the friction force between the valve stem and the packing and the thrust generated by the pressure of the medium. The force to close the valve is greater than the force to open the valve, so the valve stem The diameter of the valve should be large, otherwise the failure of the top of the valve stem will occur. According to the connection method, it is divided into three types: flange connection, thread connection and welding connection. After the appearance of the self-sealing valve, the medium flow direction of the globe valve is changed from the top of the valve disc into the valve cavity. At this time, under the action of the medium pressure, the force to close the valve is small, but the force to open the valve is large, and the diameter of the valve stem can be adjusted accordingly. decrease. At the same time, under the action of the medium, this form of valve is also tighter. my country's valve "Three Chemicals" once stipulated that the flow direction of the globe valve should be from top to bottom. When the globe valve is opened, the opening height of the valve disc is 25% to 30% of the nominal diameter. The flow rate has reached the maximum, indicating that the valve has reached the fully open position. Therefore, the fully open position of the globe valve should be determined by the stroke of the valve disc. Shut-Off Valve,Shutoff Valve,Automatic Shut Off Valve,Auto Shut Off Valve Jiangsu Qiantu Trading Co., Ltd. , https://www.jsqiantupump.com
May 20 Lanzhou Steel Market Price Quotes
The product name specification material steel factory/origin price (yuan/ton) is higher than yesterday last week than the previous month Pu line Φ6.5mm Q235 8 steel 5870 0 0 840 high line Φ6.5-10mm Q235 8980 steel -20 880 high line Φ6.5-10mm Q235 Jiu Steel 5980 0 -20 880 Rebar Φ12-14mm HRB335 Eight Steel 6080 0 0 700 Rebar Φ12-14mm HRB335 Jiu Steel 6080 0 0 700 Rebar Φ12-14mm HRB335 Longsteel 6030 0 0 690 Thread Steel Φ16-25mm HRB335 Eight Steel 5780 0 0 710 Rebar Φ16-25mm HRB335 Wine Steel 5780 0 0 710 Rebar Φ16-25mm HRB335 Longsteel 5750 0 0 710 Hot Roll 2.75*1250*C Q235 Taigang 6000 0 0 300 Hot Volume 3.0*1250*C Q235 TISCO 5950 0 0 350 Hot Roll 3.0*1250*C Q235 Steel 5550 0 0 400 Hot Roll 3.0*1250*C Q235 5600 0 0 400 Hot Roll 3.75-5.5*1500*C Q235 Jiu Steel 5750 0 0 350 Hot Roll 3.5-5.5*1500*C Q235 Jiu Steel 5750 0 0 350 Hot Roll 3.5-5.5*1500*C Q235 Eight Steel 5750 0 0 350 Cold Plate 0.5*1000*2000 08KP Steel Card 6950 0 0 200 Cold plate 1.0*1000*2000 08KP Steel plate 6800 0 0 200 Cold plate 1.0*1000*C SPCC Eight steel 6700 0 0 200 Cold coil 1.0*1000*C SPCC Steel 6750 0 0 200 Plate 8mm Q235B Jiu Steel 6950 0 0 350 Plate 10mm Q 235B Jiu Gang 6700 0 0 400 Plate 12mm Q235B Jiu Steel 6650 0 0 400 Plate 14-20mm Q235B Jiu Steel 6500 0 0 350 Plate 14-20mm Q235B Jinan Steel 6500 0 0 350 Plate 12mm Q235B Pro Steel 6500 0 0 350 Medium plate 14-20mm Q235B Lin steel 6480 0 0 350 Low alloy plate 14-20mm Q345B Wine steel 6650 0 0 300 Welded pipe 1.5 inch Q235 Clad steel 5760 0 0 110 Welded pipe 3 inch Q235 Steel 6030 0 0 100 welded pipe 4 inch Q235 steel 6180 0 0 150 seamless pipe Φ108*4.5mm 20# Angang 6800 0 0 200 seamless pipe Φ219*7mm 20# Angang 6800 0 0 250 seamless pipe Φ159*6mm 20# steel 6550 0 0 0 Seamless Pipe Φ436*11mm 20# Clad Steel 7600 0 0 0 Angle Steel 50*5# Q235 Anyang 5650 0 0 200 Angle Steel 140*12mm Q235 Tang Steel 5550 0 0 200 Channel Steel 16# Q235 A Steel 5650 0 0 200 Slot Steel 25# Q235 Laiwu Steel 5650 0 0 170 I-beam 16# Q235 Anshan Baode 6350 0 0 250 I-beam 20# Q235 Anshan Baode 6350 0 0 250