Blind flange

Blind flange, also known as flange blind or blind flange, flange cover, BL blind, the middle of the blind flange is solid, surrounded by bolt holes, and looks like an iron cover, so it is also called flange cover. Blind flange is used to seal and block the end of the pipeline, which can facilitate the removal of debris in the pipeline during maintenance. In terms of sealing effect, it has the same function as the head and pipe cap, but the head and pipe cap cannot be disassembled after welding, while the flange blind plate is fixed with bolts and is easy to disassemble

Blind flange can be divided into carbon steel according to the production material: (20 #, A3, Q235, Q23 excellent, Q235B, 20G, 16Mn, Q345, Q345R, ASTM A105, etc.); Stainless steel: (304, 304L, 316, 316L, S30408, S30403, S31608, S31603, SUS304, ASTM A403, TP321, TP317L, 347, 0Cr18Ni9, 00Cr19Ni10, 00Cr17Ni14Mo2, 1Cr18Ni9Ti, 06Cr17Ni12Mo2, 022Cr17Ni12Mo2, etc.)

Common sealing surface form codes for blind flange: convex RF, concave FM, convex M, tenon T, groove G, full plane FF, ring connection RJ

Common execution standards for blind flange: The current flange standards in China are divided into two systems, namely PN series (European system) and Class series (American system).

. The pressure markings specified in this standard are divided into PN markings and Class markings. The PN label has 12 pressure levels, namely: PN2.5; PN6; PN10; PN16; PN25; PN40; PN63; PN100; PN160; PN250; PN320; PN400。 The Class label has 6 pressure levels, namely: Class 150; Class 300; Class 600; Class 900; Class1500; Class 2500。 There are GB series (standards), JB series (mechanical department), HG series (chemical department), ASME B16.5 (American standard)

American standard: ASME B16.5, ASME B16.47

Standards: GB/T9112-2010, GB/T9119-2010, GB/T9116-2010, GB/T9115-2010

Chemical standards: HG/T20592-2009, HG/T20615-2009, HG5010-52~HG5028-58, HGJ44-91~HGJ65-91, HG20592-97