Introduction to Flanged Plate Welding Fitting
Flat Weld Flange, also known as Flange Plate or Flange Disc, has different names in various regions, but all refer to the same product.
Plate Flat Welding Flange (Full Name), PL (Abbreviation)
Features
Aesthetically pleasing, with a smooth and flat surface, highly resistant to acidity and alkali, corrosion-proof, and boasts strong texture and performance.
Specification Model
DN15-DN600
Pressure Rating
PN2.5,PN6,PN10,PN16,PN25,PN40;
Common Materials
Carbon Steel Flanges: ASTM A105, 20#, Q235, 16Mn, ASTM A350 LF1, LF2 CL1/CL2, LF3 CL1/CL2, ASTM A694 F42, F46, F48, F50, F52, F56, F60, F65, F70.
Stainless Steel Flanges: ASTM A182 F304, 304L, F316, 316L, 1Cr18Ni9Ti, 0Cr18Ni9Ti, 321, 18-8
Alloy Flanges: ASTM A182 F1, F5a, F9, F11, F12, F22, F91, A182F12, A182F11, 16MnR, Cr5Mo, 12Cr1MoV, 15CrMo, 12Cr2Mo1, A335P22, St45.8/Ⅲ
Sealing face type
Full Flange (FF), Raised Face Flange (RF)
Compliance Standards
Chemical Industry Standard: HG20593-2009, HG20615-2009
National Standards: GB/T9119-2010, GB/T2555-81
Mechanical Department Standards: JB/T81-94, JB/T74-94, JB/T75-94
Marine Standard: CB M1001-81
Form of Connection
Single-sided welding, double-sided nut connection;
In simple terms, it involves inserting the pipe into the inside diameter of the flat welding flange and welding it in place, then securing both sides with bolts and nuts.
Production Process
Pure forging, semi-forged (second choice) are suitable for SO flanges and necked butt-welding flanges; steel plates are suitable for lap-welded flanges.
AOX furnace blanking, forging or finished forging with cutting for shaping, high-precision CNC lathe turning, CNC boring mill drilling.
Advantages and Disadvantages
Advantages: Flat weld flanges not only save space and reduce weight, but more importantly, they ensure that there will be no leakage at the joint, featuring excellent sealing properties.
The reduced size of the compact flange is due to the decreased diameter of the sealing component, which in turn reduces the cross-section of the sealing surface.
The法兰gasket has been replaced by a sealing ring to ensure a proper match between the sealing faces.
This way, only minimal pressure is needed to tightly close the cover.
As the required pressure decreases, the size and quantity of the bolts can be correspondingly reduced. Therefore, a new product with a small volume and light weight (70% to 80% lighter than traditional flanges) has been designed.
Therefore, the flat welding flange is a superior type of flange product, reducing both weight and space, playing a significant role in industrial applications.
Disadvantages: The primary design flaw of a flat weld flange is that it cannot guarantee zero leakage.
Its design flaws: Connections are dynamic, and factors like thermal expansion and fluctuating cyclic loads can cause movement between flange faces, affecting the function of the flange and compromising its integrity, leading to leaks.
No product can be completely defect-free; it's about minimizing the shortcomings as much as possible. Therefore, the company strives to enhance the performance of flange plates during production, maximizing their functionality.
Procurement Recommendations
1: Recommend purchasing from a reputable flange manufacturer with a certain production scale.
2: manufacturers of flanges need to provide material inspection reports and other relevant documents for flat welding flanges.
3: Flat welding flanges must have corresponding specification and model stampings and markings.
