Blind flanges
///Class 150///
Nominal sizeConnection sizeflange thickness
DNNPSFlange outer diameter DCentral circle diameter KBolt hole diameter LNumber of bolt holes nBolt ThC
151/29060.3164M149.6
203/410069.9164M1411.2
25111079.4164M1412.7
321 1/411588.9164M1414.3
401 1/212598.4164M1415.9
502150120.7184M1617.5
652 1/2180139.7184M1620.7
803190152.4184M1622.3
1004230190.5188M1622.3
1255255215.9228M2022.3
1506280241.3228M2023.9
2008345298.58228M2027.0
25010405362.02612M2428.6
30012485431.82612M2430.2
35014535476.33012M2733.4
40016595539.83016M2735.0
45018635577.93316M3038.1
50020700635.03320M3041.3
60024815749.33620M3346.1
///CLASS 300///
Nominal sizeConnection sizeflange thickness
DNNPSFlange outer diameter DCentral circle diameter KBolt hole diameter LNumber of bolt holes nBolt ThC
151/29566.7164M1412.7
203/411582.6184M1614.3
25112588.9184M1615.9
321 1/413598.4184M1617.5
401 1/2155114.3224M2019.1
502165127.0188M1620.7
652 1/2190149.2228M2023.9
803210168.3228M2027.0
1004255200.0228M2030.2
1255280235.0228M2033.4
1506320269.92212M2035.0
2008380330.22612M2439.7
25010445387.43016M2746.1
30012520450.83316M3049.3
35014585514.43320M3052.4
40016650571.53620M3355.6
45018710628.63624M3358.8
50020775685.83624M3362.0
60024915812.84224M39X368.3
///CLASS 600///
Nominal sizeConnection sizeflange thickness
DNNPSFlange outer diameter DCentral circle diameter KBolt hole diameter LNumber of bolt holes nBolt ThC
151/29566.7164M1414.3
203/411582.6184M1615.9
25112588.9184M1617.5
321 1/413598.4184M1620.7
401 1/2155114.3224M2022.3
502165127.0188M1625.4
652 1/2190149.2228M2028.6
803210168.3228M2031.8
1004275215.9268M2438.1
1255330266.7308M2744.5
1506355292.13012M2747.7
2008420349.23312M3055.6
25010510431.83616M3363.5
30012560489.03620M3366.7
35014605527.03920M36X369.9
40016685603.24220M39X376.2
45018745654.04520M42X382.6
50020815723.94524M42X388.9
60024940838.25124M48X3101.6
///CLASS 900///
Nominal sizeConnection sizeflange thickness
DNNPSFlange outer diameter DCentral circle diameter KBolt hole diameter LNumber of bolt holes nBolt ThC
151/212082.6224M2022.3
203/413088.9224M2025.4
251150101.6264M2428.6
321 1/4160111.1264M2428.6
401 1/2180123.8304M2731.8
502215165.1268M2438.1
652 1/2245190.5308M2741.3
803240190.5268M2438.1
1004290235.0338M3044.5
1255350279.4368M3350.8
1506380317.53312M3055.6
2008470393.73912M36X363.5
25010545469.93916M36X369.9
30012610533.43920M36X379.4
35014640558.84220M39X385.8
40016705616.04520M42X388.9
45018785685.85120M48X3101.6
50020855749.35520M52X3108.0
600241040901.76820M64X3139.7
///CLASS 1500///
Nominal sizeConnection sizeflange thickness
DNNPSFlange outer diameter DCentral circle diameter KBolt hole diameter LNumber of bolt holes nBolt ThC
151/212082.6224M2022.3
203/413088.9224M2025.4
251150101.6264M2428.6
321 1/4160111.1264M2428.6
401 1/2180123.8304M2731.8
502215165.1268M2438.1
652 1/2245190.5308M2741.3
803265203.2338M3047.7
1004310241.3368M3354.0
1255375292.1428M39X373.1
1506395317.53912M36X382.6
2008485393.74512M42X392.1
25010585482.65112M48X3108.0
30012675571.55516M52X3123.9
35014750635.06016M56X3133.4
40016825704.86816M64X3146.1
45018915774.77416M70X3162.0
50020985831.88016M76X3177.8
600241170990.69416M90X3203.2
///CLASS 2500///
Nominal sizeConnection sizeflange thickness
DNNPSFlange outer diameter DCentral circle diameter KBolt hole diameter LNumber of bolt holes nBolt ThC
151/213588.9224M2030.2
203/414095.2224M2031.8
251160108.0264M2435.0
321 1/4185130.2304M2738.1
401 1/2205146.0334M3044.5
502235171.4308M2750.9
652 1/2265196.8338M3057.2
803305228.6368M3366.7
1004355273.0428M39X376.2
1255420323.8488M45X392.1
1506485368.3558M52X3108.0
2008550438.25512M52X3127.0
25010675539.86812M64X3165.1
30012760619.17412M70X3184.2
Часто задаваемые вопросы (FAQ)
What is the purpose of a blind flange?
A blind flange is used to seal the end of a pipeline, valve, or pressure vessel, effectively blocking fluid flow and preventing leaks.
Can blind flanges be used for maintenance purposes?
Yes, blind flanges can be easily unbolted to provide access for maintenance, inspection, or cleaning inside the terminal end of the pipe or pressure vessel.
Why are blind flanges sold at a premium cost compared to other flanges?
Although easier to manufacture, blind flanges are sold at a premium due to their high mechanical strength and the specific requirements for bolting forces and pressure resistance.