Bonded Washers

Bonded Washers

Sealing Australia stocks a comprehensive range of bonded washers in British imperial and German metric standards.

What is a bonded washer?

A metal washer bonded to rubber, bonded washers (aka Dowty washers) are used to prevent leakage of media through fasteners of hydraulic fittings, pipe join flanges and valve bodies. A bonded washer consists of a flat metal ring with rubber bonded to the internal diameter that is wider than the metal washer. As the bolt or fitting is tightened, it compresses the rubber seal element until fully tightened upon the metal ring creating an efficient high pressure seal.

 

Bonded-Washers-Tech-pic

 

Bonded washers size list

British Imperial Bonded Washers

Thread Size (M) Inch Thread size (M) BSP Size Reference (D) +0.13/-0mm (d1) ± 0.13mm (d) ± 0.13mm (S) Minimum Burst Pressure
(bar)
6BA 001 6.35 4.06 / 4.16 3.05 1.22 (+0.15/-0) 2150
4BA 002 7.26 5.26 4.12 1.22 (+0.15/-0) 1570
2BA 003 8.38 6.35 5.21 1.22 (+0.15/-0) 1360
1/4″ 004 13.21 8.00 6.86 1.22 (+0.15/-0) 2430
1/4″ 005 13.34 9.53 6.99 1.22 (+0.15/-0) 1680
5/16″ 006 13.34 9.53 8.31 1.22 (+0.15/-0) 1680
5/16″ 007 14.22 10.04 8.64 1.22 (+0.15/-0) 1750
3/8″ 1/8″ BSP 020 15.88 11.84 10.37 2.00 (±0.10) 1480
.40″ 008 18.36 12.45 11.26 2.00 (±0.10) 1950
7/16″ 009 19.05 13.08 11.69 2.00 (±0.10) 1890
1/2″ 1/4″ BSP 021 20.57 15.21 13.74 2.00 (±0.10) 1540
9/16″ 010 22.23 16.39 14.86 2.00 (±0.10) 1560
.60″ 022 22.23 17.30 15.83 2.00 (±0.10) 1290
5/8″ 011 25.40 18.75 16.51 2.00 (±0.10) 1560
3/8″ BSP 023 23.80 18.75 17.28 2.00 (±0.10) 1230
11/16″ 012 25.40 19.69 18.16 2.34 (+0.26/-0) 1310
3/4″ 024 26.92 21.21 19.69 2.34 (+0.26/-0) 1230
13/16″ 1/2″ BSP 025 28.58 23.01 21.54 2.34 (+0.26/-0) 1120
7/8″ 5/8″ BSP 026 31.75 24.97 23.49 2.34 (+0.26/-0) 1240
15/16″ 013 33.27 26.04 24.26 2.34 (+0.26/-0) 1275
1″ 3/4″ BSP 027 34.93 28.53 27.05 2.34 (+0.26/-0) 1050
1-1/16″ 028 38.61 30.61 27.82 2.34 (+0.26/-0) 1210
1-1/8″ 014 36.58 30.86 29.33 2.34 (+0.26/-0) 880
1-3/16″ 7/8″ BSP 029 38.10 32.39 30.81 2.34 (+0.26/-0) 860
1-1/4″ 015 41.40 35.69 32.64 3.25 (+0.26/-0) 775
1-5/16″ 1″ BSP 030 42.80 36.88 33.89 3.25 (+0.26/-0) 780
1-5/16″ 1″ BSP 031 42.80 36.88 33.89 2.34 (+0.26/-0) 780
1-3/8″ 016 44.45 38.99 35.94 3.25 (+0.26/-0) 680
1-1/2″ 017 47.75 42.04 38.96 3.25 (+0.26/-0) 660
1-5/8″ 1-1/4″ BSP 032 52.38 45.93 42.93 3.25 (+0.26/-0) 690
1-3/4″ 018 57.15 48.39 45.34 3.25 (+0.26/-0) 870
1-7/8″ 1-1/2″ BSP 033 58.60 51.39 48.44 3.25 (+0.26/-0) 690
2″ 019 63.50 54.74 51.69 3.25 (+0.26/-0) 780
2-1/8″ 1-3/4″ BSP 034 69.85 58.30 54.89 3.25 (+0.26/-0) 950
2-1/4″ 035 70.36 61.09 58.04 3.25 (+0.26/-0) 740
2″ BSP 036 73.03 63.63 60.58 3.25 (+0.26/-0) 720
2-1/4″ 037 77.72 67.44 64.39 3.25 (+0.26/-0) 750
2-1/4″ BSP 038 79.50 69.98 66.68 3.25 (+0.26/-0) 670
2-1/2″ BSP 039 90.17 79.38 76.08 3.25 (+0.26/-0) 680

German Metric Bonded Washers

Thread Size (M) Size Reference (D) mm +0.13 / -0.00 (d) ±0.10 (d1) ±0.10 (S) Min Burst Pressure (bar)
3.5 201 7.2 4.1 5.2 1.0 (±0.1) 1600
4 202 7.0 4.5 5.4 1.0 (±0.1) 1270
5 203 9.0 5.7 6.8 1.0 (±0.1) 1400
5 204 10.0 5.7 7.4 1.0 (±0.1) 1510
5.5 205 9.2 6.2 7.2 1.0 (±0.1) 1220
6 206 10.0 6.7 8.0 1.0 (±0.1) 1120
6 207 11.0 6.7 8.2 1.0 (±0.1) 1480
6 208 11.0 6.7 8.2 2.5 (±0.1) 1480
6.5 209 12.0 7.1 8.8 1.0 (±0.1) 1560
6.7 210 10.2 7.3 8.6 1.0 (±0.1) 850
8 211 13.4 8.5 9.4 1.0 (±0.1) 1780
8 212 13.0 8.7 10.0 1.0 (±0.1) 1330
8 213 14.0 8.7 10.4 1.0 (±0.1) 1510
8 214 16.0 8.7 10.4 1.0 (±0.1) 2150
8.5 215 13.3 9.3 10.5 1.0 (±0.1) 1200
10 216 16.0 10.35 12.0 2.0 (±0.1) 1470
10 217 16.0 10.7 12.4 1.5 (±0.1) 1300
10 218 18.0 10.7 12.4 1.5 (±0.1) 1880
11 219 16.3 11.4 12.7 1.5 (±0.1) 1280
11 220 18.5 11.8 13.7 1.5 (±0.1) 1540
11 221 19.1 11.8 13.5 1.5 (±0.1) 1760
12 222 18.0 12.7 14.4 1.5 (±0.1) 1150
12 223 20.0 12.7 14.4 1.5 (±0.1) 1680
13 224 20.0 13.7 15.4 1.5 (±0.1) 1340
13 225 22.0 13.7 15.4 1.5 (±0.1) 1810
13.5 226 18.7 14.0 15.7 1.5 (±0.1) 900
14 227 22.0 14.7 16.4 1.5 (±0.1) 1510
15 228 22.7 16.0 17.78 1.5 (±0.1) 1260
16 229 24.0 16.7 18.4 1.5 (±0.1) 1370
17 230 24.0 17.4 19.2 1.5 (±0.1) 1150
17.5 231 24.7 18.0 20.1 1.5 (±0.1) 1070
18 232 26.0 18.7 20.4 1.5 (±0.1) 1260
20 233 28.0 20.7 22.5 1.5 (±0.1) 1140
21 234 28.7 21.5 23.3 2.5 (±0.15) 1080
22 235 28.0 22.5 24.2 1.5 (±0.1) 760
22 236 30.0 22.7 24.4 2.0 (±0.1) 1080
22 237 30.0 22.7 24.4 3.0 (±0.1) 1080
24 238 32.0 24.7 26.4 2.0 (±0.1) 1000
26 239 35.0 28.4 26.7 2.0 (±0.1) 1050
27 240 36.0 27.2 29.0 2.0 (±0.1) 1130
30 242 39.0 31.0 33.0 2.0 (±0.1) 870
33 243 42.0 33.7 35.8 2.0 (±0.1) 840
33 244 43.0 34.3 36.4 2.0 (±0.1) 870
36 245 46.0 36.7 38.8 2.0 (±0.1) 890
39 246 51.0 40.0 41.9 2.5 (±0.1) 1030
42 247 53.0 42.7 44.4 3.0 (±0.15) 930
48 248 59.0 48.7 50.8 3.0 (±0.15) 790
51 249 60.0 52.0 54.1 3.0 (±0.15) 540
52 250 64.5 53.3 56.4 3.0 (±0.15) 710
60 251 73.0 60.7 63.0 3.0 (±0.15) 780
68 252 79.5 68.6 72.1 3.5 (±0.15) 510
75 253 90.3 76.08 79.1 3.38 (±0.15) 700
88 254 101.48 89.09 92.1 3.25 (±0.15) 510
125 255 143.67 127.0 132.7 5.0 (±0.15) 420


 

Self Centring Bonded Washers

Self centring bonded washers are essentially the same design as the standard Dowty type washers but include an additional non-sealing lip on the ID that locates the washer at the centre of a bolt hole without having to hold and manually locate washer while tightening fasteners.

 

Self Centring Bonded Washers

Self centring range feature both metric and imperial sizes.

Thread Size (M) Size Reference (D) ±0.13mm (d1) ±0.10mm (d) ±0.13mm (C) Centring Lip (S) ±0.10mm
M8 866 14.00 10.40 8.70 6.40 1.00
1/8″ BSP 820 15.88 11.84 10.37 8.26 2.00
M10 708 16.00 12.40 10.70 8.05 1.50
M12 867 19.00 14.10 12.70 9.73 1.50
1/4″ BSP 821 20.57 15.21 13.74 11.18 2.00
M14 868 22.00 16.40 14.70 11.38 1.50
5/8″ 869 25.40 18.75 16.51 12.90 2.00
M16 870 24.00 18.40 16.70 13.41 1.50
3/8″ BSP 823 23.80 18.75 17.28 14.76 2.00
11/16″ 871 25.40 19.69 18.16 14.50 2.40
M18 872 26.00 20.40 18.70 14.76 1.50
M20 873 28.00 22.50 20.70 16.76 1.50
1/2″ BSP 825 28.58 23.01 21.54 18.24 2.47
M22 874 30.00 24.40 22.70 18.74 2.00
5/8″ BSP 826 31.75 24.97 23.49 20.27 2.47
M24 875 32.00 26.40 24.70 20.11 2.00
3/4″ BSP 827 34.93 28.53 27.05 23.83 2.47
7/8″ BSP 829 38.10 32.29 30.81 27.51 2.47
1″ BSP 830 42.80 36.88 33.89 29.92 3.40
1-1/4″ BSP 832 52.38 45.93 42.93 38.45 3.40
1-1/2″ BSP 833 58.60 51.39 48.44 44.45 3.40
1-3/4″ BSP 834 69.85 58.30 54.89 50.42 3.40
2″ BSP 836 73.03 63.63 60.58 56.26 3.40
2-1/4″ BSP 838 79.50 69.98 66.68 62.36 3.40
2-1/2″ BSP 839 90.17 79.38 76.08 71.50 3.40

 

Bonded Washer Kit

Sealing Australia stocks a 280 piece bonded washer kit featuring popular metric and imperial sizes.

Bonded Washer Kit

Size Reference Thread Qty
004 10
005 10
006 10
010 10
012 10
020 1/8″ BSP 10
021 1/4″ BSP 10
022 10
023 3/8″ BSP 10
024 10
025 1/2″ BSP 5
026 5
027 5
029 7/8″BSP 5
030 1″ BSP 5
031 1″ BSP 5
203 M5 10
206 M6 10
212 M8 10
215 M8.5 10
217 M10 10
222 M12 10
223 M12 10
225 M13 10
227 M14 10
229 M16 10
232 M18 10
233 M20 10
236 M22 5
238 M24 5
239 M26 5
240 M27 5
242 M30 5
243 M33 5

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