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The full name of the neck flat welding flange is the neck flat
welding steel pipe flange, which extends the steel pipe, pipe
fittings, etc. Into the flange and connects with the equipment or pipeline through
the fillet weld.
The main differences between the butt welding flange and the flat
welding flange are different weld forms, different materials,
different nominal pressures and different connection methods.Different weld forms: the flat weld cannot be radiographed, while
the butt weld can.
The form of welding seam between the pipe with neck flat welding
flange and the flange is fillet weld, while the form of welding
seam between the flange with neck flat welding and the pipe is
circumferential weld. The form of flat welding is two fillet weld, and the form of butt
welding is one butt circumferential weld.
1. The difference between the neck flat welding flange and the neck
free flat welding flange is that the neck flat welding flange is
more than the neck free flat welding flange in the pipeline welding
position.
2. The neck free flat welding flange is also a flat flange, and the
boss without flange is also a flat fillet weld.
3. The weld joint between the neck butt welding flange and the
connecting pipe belongs to class B seam, and the weld joint between
the neck flat welding flange and the connecting pipe belongs to
class C seam. The NDT after welding is different.
4. Different materials: the material of welding flange with neck is
machined from ordinary steel plate with thickness meeting the
requirements, while the material of welding flange with neck is
mostly machined from forged steel parts.
5. Different nominal pressure: the nominal pressure of flat welding
flange with neck is 0.6-4.0mpa, while the nominal pressure of flat
welding flange with neck is 1-25mpa.
6. Obviously, the applicable pressure level of flat welding flange
with neck is lower.
1. Different connection methods: the biggest difference between the
neck flat welding flange and the neck butt welding flange in
structure lies in the connection method between the nozzle and the
flange.
2. Generally, the neck flat welding flange is the fillet connection
between the nozzle and the flange, while the neck butt welding
flange is the butt joint between the flange and the nozzle.
3. The sealing surface forms of welding flange with neck are: RF,
FM, m, t, G and FF. Diameter range of flat welding flange with
neck: dn10 ~ DN600.
4. Scope of application: PN series pn2.5 ~ PN40; class series
class150 ~ class1500.
5. Flange material: carbon steel, Luomo steel, 304, 316, 304L,
316L, 321, 347, cf8c.
Application scope of flange sealing surface | |||||
Sealing surface form | Nominal pressure (MPA) | ||||
0.6 | 1.0 | 1.6 | 2.5 | 4 | |
Bursting surface (RF) | DX10—300 | DN10—600 | |||
Bump face (MFM) | DN10—600 | ||||
Vertebral groove surface (TG) | — | DN10—600 | |||
Full plane (FF) | DX10—300 | DN10—600 | — |
1, Advantages: the neck flat welding flange also belongs to the
flat welding flange, because it has a short neck, thus improving
the strength of the flange and improving the bearing strength of
the flange. So it can be used on pipes with higher pressure.
2, Disadvantages: compared with plate type flat welding flange, the
cost is higher, because of its shape characteristics, it is easier
to bump during transportation.
1, The welding flange with neck is used for corrosion-resistant,
highly toxic, flammable and explosive occasions.
2, The sealing surface of flat welding flange with neck can be
convex, concave and mortise face.
3, The sealing effect is not the same, and the bearing strength is
not the same.
4, There is a short neck behind the tail of flat welding flange
with neck, which can improve the rigidity of flange.
5, The bearing capacity is higher than that of flat welding flange,
which is generally used in medium and high pressure occasions.
a. Plastic bubble bag package b.Wove bag package c.Pallet d. Customized
Our Steel flat factory have high ability for production, the delivery time is 45days for small quantity, or if you are hurry for that, we can arrange and meet your shipping date.