HG/T 20611-2009Covered serrated metal gaskets for use with steel pipe flanges (PN designated) (English PDF)

1 Scope

This standard specifies the type, dimension, technical requirements, labeling and marking of covered serrated metal gaskets for steel pipe flanges (PN designated).

This standard is applicable to covered serrated metal gaskets for steel pipe flanges specified in HG/T 20592 whose nominal pressure is PN16~PN160.

2 Normative References

The following standards contain provisions which, through reference in this text, constitute provisions of this national standard. For dated reference, subsequent amendments (excluding amending error in the text) to, or revisions of, any of these publications do not apply. However, parties to agreement based on this standard are encouraged to research whether the latest editions of these references are applied or not. For undated references, the latest edition of the normative document is applicable to this national standard.

"Hot-rolled Plain Carbon and Low Alloy Structural Steel Sheets and Strips" GB/T 912 "Hot Rolled Stainless Steel Plate Sheets and Strips" GB/T 4237"Cold Rolled Stainless Steel Plate Sheets and Strips" GB/T 3280 "Steel Pipe Flanges (PN designated)" HG/T 20592 "Specification for Selection of Steel Pipe Flanges, Gaskets and Bolting (PN designated)" HG/T 20614 "Specification for Flexible Graphite Plates" TB/T 7758.2 "PTFE Sheers" QB/T 3625

3 General Provisions

4 Dimension

The dimension of gaskets shall meet the provisions of Figure 4, Table 4-1 and Table 4-2."h" in Figure 4 is the minimum value.

Table 4-1 Dimension of Centring Ring (B type or C type) Gaskets for Raised Face Flanges (mm)

Nominal

dimension

Serrated metal ring

Outside diameter of centring ringD1 Thickness of serrated metal ring Thickness of integral centring ring Thickness of mobile centring ring t1 Cladding thickness Inside diameter D3 Outside diameterD2 PN16~PN40 PN 63~PN160 PN16 PN25 PN40 PN63 PN100 PN160 10 22 36 36 46 56 15 26 42 42 51 61 20 31 47 47 61 72 25 36 52 52 7l 82 32 46 62 62 82 88 40 53 69 69 92 103 50 65 81 81 107 113 119 65 81 100 100 127 138 144 80 95 115 115 142 148 154 100 118 138 138 162 168 174 180 125 142 162 162 192 194 210 217 150 170 190 190 218 224 247 257 200 220 240 248 273 284 290 309 324 4.0 250 270 290 300 329 340 352 364 391 388 300 320 340 356 384 400 417 424 458 458 2.0 1.5 0.5 350 375 395 415 444 457 474 486 512 ___ 400 426 450 474 495 514 546 543 572 ___ 450 480 506 ___ 555 564 571 ___ ___ ___ 500 530 560 ___ 617 624 628 ___ ___ ___ 600 630 664 ___ 734 731 747 ___ ___ ___ 700 730 770 ___ 804 833 ___ ___ ___ ___ 800 830 876 ___ 911 942 ___ ___ ___ ___ 900 930 982 ___ 1011 1042 ___ ___ ___ ___ 1000 1040 1098 ___ 1128 1155 ___ ___ ___ ___ 1200 1250 1320 ___ 1342 1365 ___ ___ ___ ___ 1400 1440 1522 ___ 1542 ___ ___ ___ ___ ___ 1600 1650 1742 ___ 1764 ___ ___ ___ ___ ___ 5.0 1800 1850 1914 ___ 1964 ___ ___ 2000 2050 2120 ___ 2168 ___ ___

1 Generally, the serrated metal ring is integrally constructed. If weld structure is adopted, the following requirements shall be complied with.

1) Get approval from the users;

2) Complete penetration type shall be adopted as welding seam structure; there shall be no more than two soldered joints and stress-relief heat treatment shall be carried out after welding;

3) Before covering the cladding, the serrated form and dimension of the weld part shall be in accordance with other parts.

2 The planeness of serrated metal ring shall be no bigger than 1/100 of the outside diameter of the gasket.

3 The cladding materials shall be fixed firmly on the serrated metal ring so that they won't scale off during the transportation or assembly process. The adhesive used shall have no corrosion to the metallic materials. There shall be no more than two scabbed joints, if overlapping is adopted, the overlap section shall be connected through bias cutting; if abutting is adopted, a thinner cladding material shall be covered at the seam crossing.

4 There shall be proper clearance between the centering groove between the mobile centering ring and serrated metal ring so that when it expands at heating, it will not disturb movement. Welding method may be adopted for mobile centering ring.

6 Inspection

6.0.1 The material, dimension, appearance and manufacture of gaskets shall be compliant to the provisions of this standard.

6.0.2 Other inspection requirements may be determined through negotiating with the producers at ordering.

7 Labeling