EN 1092 consists of the following four parts:
Part 1: Steel flanges;
Part 2: Cast iron flanges;
Part 3: Copper alloy flanges;
Part 4: Aluminium alloy flanges.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. This European Standard for a single series of flanges specifies requirements for circular steel flanges in PN designations PN 2,5 to PN 400 and nominal sizes from DN 10 to DN 4000. This European Standard specifies the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/ temperature ratings and approximate flange masses. For the purpose of this European Standard, “flanges” include also lapped ends and collars.
Inspection and testing of bended and electric welded flanges or collars from formed bars, sectional steel or band material
a) Welded joints shall be visually examined in accordance with EN 970 before any other NDT is performed. Acceptance criteria in accordance with EN ISO 5817 surface imperfections level C.
b) The area to be examined shall include the weld metal and the heat affected zones.
c) All base material for these flanges, such as plates or flat products shall be inspected ultrasonically according to EN 10160. Scope of test according to EN 10160:199, Table 3, acceptance criteria Class S2 and EN 10160:1999, Table 5 Class E3.
d) Flanges made of steels in Material Groups 1E0, 1E1, 2E0 and 3E1 are subjected by the flange manufacturer to ultrasonic testing or to radiographic testing with reference to Table 5 to the extend defined in Table 5. As a rule, flanges that are produced by continuous welding with the same machine setting are grouped together to form a test batch.
e) Finished flanges of all other material groups are subjected by the flange manufacturer to ultrasonic inspection or to radiographic inspection in the weld zone according to Table 5 on each flange.
f) Flanges with unit weights > 300 kg shall be inspected ultrasonically or radiographically according to Table 5 in all material groups.
g) All welds shall be tested by the flange manufacturer for the presence of surface cracks with a suitable method as Penetrant Testing for austenitic base or filler material and Magnetic Particle Testing for Ferritic material according to Table 5.The following materials constitute exceptions: P 235 GH, P 265 GH and P 250 GH.
h) The non-destructive testing shall be carried out after completion of possible post-weld heat treatment (PWHT). Where a material is not sensitive to PWHT cracking e.g. material groups 1.1 and 8.1 (see CEN ISO/TR 15608), NDT may be performed before PWHT.
