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Date Published:Jun. 18. 2015

Plain Washers

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Plain Washers

Small size - Shape and dimensions of part grade A

Small size - Shape of part grade A

Unit : mm
Nominal diameter of
plain washer＊(Nominal diameter of
thread d) 		 Inside diameter d1  Outside diameter d2  Thickness h 
Basic dimension
(Min.)
 Max.  Basic dimension
(Max.)
 Min.
 Basic Dimension  Max.  Min.
1.6    1.70   1.84   3.5   3.2  0.3  0.35  0.25
2   2.20   2.34   4.5   4.2  0.3  0.35  0.25
2.5   2.70   2.84   5.0   4.7  0.5  0.55  0.45
3   3.20   3.38   6.0   5.7  0.5  0.55  0.45
(3.5)   3.70   3.88   7.00   6.64  0.5  0.55  0.45
4   4.30   4.48   8.00   7.64  0.5  0.55  0.45
5   5.30   5.48   9.00   8.64  1  1.1  0.9
6   6.40   6.62 11.00 10.57  1.6  1.8  1.4
8   8.40   8.62 15.00 14.57  1.6  1.8  1.4
10 10.50 10.77 18.00 17.57  1.6  1.8  1.4
12 13.00 13.27 20.00 19.48  2  2.2  1.8
(14) 15.00 15.27 24.00 23.48  2.5  2.7  2.3
16 17.00 17.27 28.00 27.48  2.5  2.7  2.3
(18) 19.00 19.33 30.00 29.48  3  3.3  2.7
20 21.00 21.33 34.00 33.38  3  3.3  2.7
(22) 23.00 23.33 37.00 36.38  3  3.3  2.7
24 25.00 25.33 39.00 38.38  4  4.3  3.7
(27) 28.00 28.33 44.00 43.38  4  4.3  3.7
30 31.00 31.39 50.00 49.38  4  4.3  3.7
(33) 34.00 34.62 56.00 54.8  5  5.6  4.4
36 37.00 37.62 60.00 58.8  5  5.6  4.4

＊ Parenthesized nominal diameter of thread represents Choice 2.

Standard size - Part grade A and standard-sized chamfering＊2 - Shape and dimensions of part grade A

Standard size - Shape of part grade A

18_technical-18-plain-washers-1

Standard-sized chamfering - Shape of part grade A

18_technical-18-plain-washers-2
Unit : mm
Nominal diameter of
plain washer＊1 (Nominal diameter of
thread d)
 Inside diameter d1  Outside diameter d2  Thickness h 
Basic dimension
(Min.)
 Max.  Basic dimension
(Max.)
 Min.  Basic dimension Max.  Min. 
1.6    1.70   1.84   4.0   3.7 0.3 0.35 0.25
2   2.20   2.34   5.0   4.7 0.3 0.35 0.25
2.5   2.70   2.84   6.0   5.7 0.5 0.55 0.45
3   3.20   3.38   7.00   6.64 0.5 0.55 0.45
(3.5)   3.70   3.88   8.00   7.64 0.5 0.55 0.45
4   4.30   4.48   9.00   8.64 0.8 0.9 0.7
5   5.30   5.48 10.00   9.64 1 1.1 0.9
6   6.40   6.62 12.00 11.57 1.6 1.8 1.4
8   8.40   8.62 16.00 15.57 1.6 1.8 1.4
10 10.50 10.77 20.00 19.48 2 2.2 1.8
12 13.00 13.27 24.00 23.48 2.5 2.7 2.3
(14) 15.00 15.27 28.00 27.48 2.5 2.7 2.3
16 17.00 17.27 30.00 29.48 3 3.3 2.7
(18) 19.00 19.33 34.00 33.38 3 3.3 2.7
20 21.00 21.33 37.00 36.38 3 3.3 2.7
(22) 23.00 23.33 39.00 38.38 3 3.3 2.7
24 25.00 25.33 44.00 43.38 4 4.3 3.7
(27) 28.00 28.33 50.00 49.38 4 4.3 3.7
30 31.00 31.39 56.00 55.26 4 4.3 3.7
(33) 34.00 34.62 60.0 58.8 5 5.6 4.4
36 37.00 37.62 66.0 64.8 5 5.6 4.4

＊1  Parenthesized nominal diameter of thread represents Choice 2.
＊2  Standard-sized chamfering - Shall be specified for nominal diameter of thread 5 or above among applicable part grade A threads.

Standard size - Shape and dimensions of part grade C

Standard size - Shape of part grade C

Unit : mm
Nominal diameter of
plain washer＊
(Nominal diameter of
thread d)
 Inside diameter d1  Outside diameter d2  Thickness h 
Basic dimension
(Min.)
 Max.  Basic dimension
(Max.)
 Min.
 Basic dimension Max.  Min.
1.6    1.80   2.05   4.00   3.25 0.3 0.4 0.2
2   2.40   2.65   5.00   4.25 0.3 0.4 0.2
2.5    2.90   3.15   6.00   5.25 0.5 0.6 0.4
3   3.4   3.7   7.0   6.1 0.5 0.6 0.4
(3.5)   3.9   4.2   8.0   7.1 0.5 0.6 0.4
4   4.5   4.8   9.0   8.1 0.8 1 0.6
5   5.5   5.8 10.0   9.1 1 1.2 0.8
6   6.60   6.96 12.0 10.9 1.6 1.9 1.3
8   9.00   9.36 16.0 14.9 1.6 1.9 1.3
10 11.00 11.43 20.0 18.7 2 2.3 1.7
12 13.50 13.93 24.0 22.7 2.5 2.8 2.2
(14) 15.50 15.93 28.0 26.7 2.5 2.8 2.2
16 17.50 17.93 30.0 28.7 3 3.6 2.4
(18) 20.00 20.52 34.0 32.4 3 3.6 2.4
20 22.00 22.52 37.0 35.4 3 3.6 2.4
(22) 24.00 24.52 39.0 37.4 3 3.6 2.4
24 26.00 26.52 44.0 42.4 4 4.6 3.4
(27) 30.00 30.52 50.0 48.4 4 4.6 3.4
30 33.00 33.62 56.0 54.1 4 4.6 3.4
(33) 36 37 60.0 58.1 5 6 4
36 39 40 66.0 64.1 5 6 4

＊Parenthesized nominal diameter of thread represents Choice 2.

Large size - Shape and dimensions of part grade A or C

Large size - Shape of part grade A

18_technical-18-plain-washers-3

Large size - Shape of part grade C

18_technical-18-plain-washers-4
Unit : mm
Nominal diameter of
plain washer＊
(Nominal diameter of
thread d)
 Inside diameter d1  Outside diameter d2  Thickness h
Basic dimension
(Min.)
 Max.  Basic dimension
(Max.)
 Min.  Basic dimension Max.  Min. 
Part grade Part grade Part grade Part grade
 Part grade Part grade Part grade
A  C   A C  A and C  A  C  A and C  A  C  A  C 
3   3.20   3.4   3.38   3.7     9.00     8.64     8.1 0.8 0.9 1.0 0.7 0.6
(3.5)    3.70   3.9   3.88   4.2   11.00   10.57     9.9 0.8 0.9 1.0 0.7 0.6
4   4.30   4.5   4.48   4.8   12.00   11.57   10.9 1 1.1 1.2 9 0.8
5   5.30   5.5   5.48   5.8   15.00   14.57   13.9 1 1.1 1.2 9 0.8
6   6.40   6.60   6.62   6.96   18.00   17.57   16.9 1.6 1.8 1.9 1.4 1.3
8   8.40   9.00   8.62   9.36   24.00   23.48   22.7 2 2.2 2.3 1.8 1.7
10 10.50 11.00 10.77 11.43   30.00   29.48   28.7 2.5 2.7 2.8 2.3 2.2
12 13.00 13.50 13.27 13.93   37.00   36.38   35.4 3 3.3 3.6 2.7 2.4
(14) 15.00 15.50 15.27 15.93   44.00   43.38   42.4 3 3.3 3.6 2.7 2.4
16 17.00 17.50 17.27 17.93   50.00   49.38   48.4 3 3.3 3.6 2.7 2.4
(18) 19.00 20.00 19.33 20.52   56.00   55.26   54.1 4 4.3 4.6 3.7 3.4
20 21.00 22.00 21.33 22.52   60.00   59.26   58.1 4 4.3 4.6 3.7 3.4
(22) 23.00 24.00 23.52 24.84   66.0   64.8   64.1 5 5.6 6 4.4 4
24 25.00 26.00 25.52 26.84   72.0   70.8   70.1 5 5.6 6 4.4 4
(27) 30.00 30.00 30.52 30.84   85.0   83.6   82.8 6 6.6 7 5.4 5
30 33.00 33.00 33.62 34   92.0   90.6   89.8 6 6.6 7 5.4 5
(33) 36.00 36.00 36.62 37 105.0 103.6 102.8 6 6.6 7 5.4 5
36 39.00 39.00 39.62 40 110.0 108.6 107.8 8 9 9.2 7 6.8

＊Parenthesized nominal diameter of thread represents Choice 2.


Super-large size - Shape and dimensions of part grade C

Super-large size - Shape of part grade C

Unit : mm
Nominal diameter of
plain washer＊
(Nominal diameter of
thread d)
 Inside diameter d1  Outside diameter d2  Thickness h 
Basic dimension
(Min.) 		 Max.  Basic dimension
(Max.) 		 Min.  Basic dimension Max.  Min. 
5    5.5   5.8   18.0   16.9 2 2.3 1.7
6    6.60   6.96   22.0   20.7 2 2.3 1.7
8   9.00   9.36   28.0   26.7 3 3.6 2.4
10 11.00 11.43   34.0   32.4 3 3.6 2.4
12 13.50 13.93   44.0   42.4 4 4.6 3.4
(14) 15.50 15.93   50.0   48.4 4 4.6 3.4
16 17.5 18.2   56.0   54.1 5 6 4
(18) 20.00 20.84   60.0   58.1 5 6 4
20 22.00 22.84   72.0   70.1 6 7 5
(22) 24.00 24.84   80.0   78.1 6 7 5
24 26.00 26.84   85.0   82.8 6 7 5
(27) 30.00 30.84   98.0   95.8 6 7 5
30 33 34 105.0 102.8 6 7 5
(33) 36 37 115.0 112.8 8 9.2 6.8
36 39 40 125.0 122.5 8 9.2 6.8

＊ Parenthesized nominal diameter of thread represents Choice 2.



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