如何决定B的尺寸

密封件的公称尺寸 腔体尺寸 标准型（A505） 耐热型（F357） d D h φd φD φD1 HA HB C NOK部品番号 名义号 NOK部品番号 名义号 6.3 16.3 7.5 6.3 16.3 15.3 8.5 10.5 2.5 CU3308D0 UPH-6.3     16.3 8 6.3 16.3 15.3 9 11 CU0024D0 UPH-6.3A     7.1 17.1 7.5 7.1 17.1 16.1 8.5 10.5 CU3309D0 UPH-7.1     17.1 8 7.1 17.1 16.1 9 11 CU0030D0 UPH-7.1A     8 18 7.5 8 18 17 8.5 10.5 CU0042D0 UPH-8     18 8 8 18 17 9 11 CU0043D1 UPH-8A CU0043D2 UPH-8AF 9 19 7.5 9 19 18 8.5 10.5 CU3310D0 UPH-9     19 8 9 19 18 9 11 CU0054D0 UPH-9A     10 20 7.5 10 20 19 8.5 10.5 CU0068D0 UPH-10     20 8 10 20 19 9 11 CU0069D1 UPH-10A     11.2 21.2 7.5 11.2 21.2 20.2 8.5 10.5 CU3311D0 UPH-11.2     21.2 8 11.2 21.2 20.2 9 11 CU0081D0 UPH-11.2A     12 25 8 12 25 24 9 11 CU0093D0 UPH-12 CU0093D3 UPH-12F 12.5 22.5 7.5 12.5 22.5 21.5 8.5 10.5 CU3312D0 UPH-12.5     22.5 8 12.5 22.5 21.5 9 11 CU0102D0 UPH-12.5A     14 24 7.5 14 24 23 8.5 10.5 CU0121D0 UPH-14     24 8 14 24 23 9 11 CU0122D0 UPH-14A CU0122D3 UPH-14AF 15 25 8 15 25 24 9 11 CU0135D0 UPH-15A     28 10 15 28 27 11 13 CU0137D0 UPH-15     16 26 7.5 16 26 25 8.5 10.5 CU0156D0 UPH-16 CU0156D2 UPH-16F 26 8 16 26 25 9 11 CU0157D1 UPH-16A     32 10 16 32 31 11 13 CU0161D0 UPH-16B     18 28 8 18 28 27 9 11 CU0182D0 UPH-18A CU0182D4 UPH-18AF 31 10 18 31 30 11 13 3.5 CU0186D0 UPH-18     33 10 18 33 32 11 13 CU2196D0 UPH-18B     18.5 31.5 10 18.5 31.5 30.5 11 13 CU3313D0 UPH-18.5     20 30 8 20 30 29 9 11 CU0215D1 UPH-20A CU0215D2 UPH-20AF 33 10 20 33 32 11 13 CU0221D0 UPH-20     35 10 20 35 34 11 13 CU0224D0 UPH-20B     21.5 31.5 8 21.5 31.5 30.5 9 11 CU0239D0 UPH-21.5     22 35 10 22 35 34 11 13 CU0249D0 UPH-22     22.4 32.4 8 22.4 32.4 31.4 9 11 CU0263D0 UPH-22.4A CU0263D3 UPH-22.4AF 35.4 10 22.4 35.4 34.4 11 13 CU0265D1 UPH-22.4     25 35 8 25 35 34 9 11 CU0282D2 UPH-25A CU0282D3 UPH-25AF 38 10 25 38 37 11 13 CU0288D0 UPH-25     40 10 25 40 39 11 13 CU0292D0 UPH-25B CU0292D4 UPH-25BF 45 12 25 45 44 13 15 CU0301D0 UPH-25C     25.5 35.5 8 25.5 35.5 34.5 9 12 CU0309D0 UPH-25.5     27 40 10 27 40 39 11 14 CU2347D0 UPH-27     28 40 10 28 40 39 11 14 CU0330D2 UPH-28A CU0330D6 UPH-28AF 41 10 28 41 40 11 14 CU0335D0 UPH-28     43 10 28 43 42 11 14 CU0340D0 UPH-28B     30 43 10 30 43 42 11 14 CU0364D0 UPH-30 CU0364D2 UPH-30F 45 10 30 45 44 11 14 CU0368D2 UPH-30A CU0368D8 UPH-30AF 31.5 44.5 10 31.5 44.5 43.5 11 14 CU0385D0 UPH-31.5     46.5 10 31.5 46.5 45.5 11 14 CU0387D1 UPH-31.5A     32 45 10 32 45 44 11 14 CU2451D0 UPH-32     46 10 32 46 45 11 14 CU0403D0 UPH-32A     48 10 32 48 47 11 14 CU0404D0 UPH-32B     34 50 12 34 50 49 13 16 CU0408D0 UPH-34     35 50 10 35 50 49 11 14 4 CU0437D4 UPH-35B CU0437D5 UPH-35BF 50 12 35 50 49 13 16 CU0438D0 UPH-35     51 12 35 51 50 13 16 CU0441D0 UPH-35A     35.5 50.5 10 35.5 50.5 49.5 11 14 CU0456D2 UPH-35.5A CU0456D6 UPH-35.5AF 51.5 12 35.5 51.5 50.5 13 16 CU0458D0 UPH-35.5 CU0458D2 UPH-35.5F 38 52 10 38 52<