可用于測量“大管徑小流量”或“大管徑低流速”管道中流體流量,將不好測量變?yōu)榭梢哉y量,如管道中的小蒸汽流量、小氣體流量和小潔凈液體流量等。特點(diǎn)如下:
*流量計口徑可縮小但不改變與工藝管道連接尺寸,即無需做縮管改動;
*儀表口徑縮徑后,具有一定的整流作用,可測下限流速將會變得更低;
*測量液體最低流速為0.3 m/s,量程比10:1;
*測量蒸汽和氣體最低流速為3m/s,量程比10:1;
*流量計向小縮徑的等級原則上無限制,但要考慮到壓力損失的大小。
如何正確選擇儀表口徑
儀表選型是能否用好流量計的重要工作,要獲得準(zhǔn)確的測量結(jié)果,選型時應(yīng)該注意,介質(zhì)溫度、壓力、流量范圍及安裝環(huán)境等技術(shù)參數(shù),其中流量范圍的選擇尤為重要,流量太小儀表難以檢測出信號,流量太大,儀表容易超量程。(下表中儀表口徑對應(yīng)流量范圍僅供參考)
1、測量飽和蒸汽流量范圍 (口徑DN:mm;流量單位:t/h)
DN
|
0.1MPa
|
0.2 MPa
|
0.3 MPa
|
0.4 MPa
|
0.5 MPa
|
0.6 MPa
|
||||||
6
|
0.6—5.6 Kg/h
|
0.8—8.2 Kg/h
|
1.1—10.8 Kg/h
|
1.3—13.3 Kg/h
|
1.6—15.8 Kg/h
|
1.8—18.3 Kg/h
|
||||||
8
|
1.0—10.0 Kg/h
|
1.5—14.7 Kg/h
|
1.9—19.2 Kg/h
|
2.4—23.7 Kg/h
|
2.8—28.1Kg/h
|
3.3—32.6 Kg/h
|
||||||
10
|
1.6—15.7 Kg/h
|
2.3—22.9Kg/h
|
3.0—30.0 Kg/h
|
3.7—37.0 Kg/h
|
4.4—44.0 Kg/h
|
5.1—50.9 Kg/h
|
||||||
15
|
3.5—35 Kg/h
|
5.1—51 Kg/h
|
6.7—67 Kg/h
|
8.3—83 Kg/h
|
9.8—98 Kg/h
|
11.4—114 Kg/h
|
||||||
20
|
6.2—62 Kg/h
|
9.1—91 Kg/h
|
12—120 Kg/h
|
15—150 Kg/h
|
17.5—175 Kg/h
|
20.3—203 Kg/h
|
||||||
25
|
9.7—97 Kg/h
|
14.3—143 Kg/h
|
18.7—187 Kg/h
|
23.1—231 Kg/h
|
27.4—274 Kg/h
|
31.7—317 Kg/h
|
||||||
32
|
16—160 Kg/h
|
23.4—234 Kg/h
|
30.7—307 Kg/h
|
37.9—379 Kg/h
|
45—450 Kg/h
|
51—510 Kg/h
|
||||||
40
|
25.8—258 Kg/h
|
36.6—366 Kg/h
|
48—480 Kg/h
|
59.2—592 Kg/h
|
70.3—703 Kg/h
|
81.3—813 Kg/h
|
||||||
50
|
0.04
|
0.39
|
0.05
|
0.58
|
0.07
|
0.76
|
0.09
|
0.93
|
0.11
|
1.10
|
0.13
|
1.30
|
65
|
0.06
|
0.67
|
0.09
|
0.97
|
0.13
|
1.30
|
0.16
|
1.60
|
0.19
|
1.90
|
0.21
|
2.10
|
80
|
0.10
|
1.00
|
0.14
|
1.40
|
0.19
|
1.90
|
0.24
|
2.40
|
0.28
|
2.80
|
0.33
|
3.30
|
100
|
0.15
|
1.50
|
0.23
|
2.30
|
0.3
|
3.0
|
0.37
|
3.70
|
0.44
|
4.40
|
0.51
|
5.10
|
125
|
0.23
|
2.30
|
0.36
|
3.60
|
0.47
|
4.70
|
0.58
|
5.80
|
0.69
|
6.90
|
0.79
|
7.90
|
150
|
0.33
|
3.30
|
0.51
|
5.10
|
0.68
|
6.80
|
0.83
|
8.30
|
0.99
|
9.90
|
1.14
|
11.4
|
200
|
0.63
|
6.3
|
0.92
|
9.2
|
1.20
|
12.0
|
1.48
|
14.8
|
1.76
|
17.6
|
2.03
|
20.4
|
250
|
0.98
|
9.79
|
1.43
|
14.32
|
1.88
|
18.76
|
2.31
|
23.14
|
2.75
|
27.47
|
3.18
|
31.79
|
300
|
1.41
|
14.10
|
2.06
|
20.61
|
2.70
|
27.01
|
3.33
|
33.32
|
3.96
|
39.56
|
4.58
|
45.78
|
350
|
1.92
|
19.20
|
2.81
|
28.06
|
3.68
|
36.76
|
4.54
|
45.35
|
5.38
|
53.85
|
6.23
|
62.31
|
400
|
2.51
|
25.07
|
3.66
|
36.65
|
4.80
|
48.02
|
5.92
|
59.23
|
7.03
|
70.33
|
8.14
|
81.39
|
450
|
3.17
|
31.73
|
4.64
|
46.38
|
6.08
|
60.77
|
7.50
|
74.97
|
8.90
|
89.02
|
10.30
|
103.0
|
500
|
3.92
|
39.18
|
5.73
|
57.26
|
7.50
|
75.03
|
9.26
|
92.55
|
10.99
|
109.9
|
12.72
|
127.2
|
600
|
5.64
|
56.41
|
8.25
|
82.46
|
10.80
|
108.0
|
13.33
|
133.3
|
15.83
|
158.3
|
18.31
|
183.1
|
DN
|
0.7 MPa
|
0.8 MPa
|
0.9 MPa
|
1.0 MPa
|
1.1 MPa
|
|||||
6
|
2.1—20.8 Kg/h
|
2.3—23.2Kg/h
|
2.6—25.7Kg/h
|
2.8—28.1Kg/h
|
3.1—30.6Kg/h
|
|||||
8
|
3.7—36.9 Kg/h
|
4.1—41.3 Kg/h
|
4.6—45.7 Kg/h
|
5.0—50.0Kg/h
|
5.4—54.4 Kg/h
|
|||||
10
|
5.8—57.7 Kg/h
|
6.5—64.5 Kg/h
|
7.1—71.4Kg/h
|
7.8—78.2 Kg/h
|
8.5—85.0 Kg/h
|
|||||
15
|
13.0—130Kg/h
|
14.5—145 Kg/h
|
16.1—161 Kg/h
|
17.6—176 Kg/h
|
19.1—191 Kg/h
|
|||||
20
|
23.1—231 Kg/h
|
25.8—258 Kg/h
|
28.5—285 Kg/h
|
31.3—313 Kg/h
|
34.0—340 Kg/h
|
|||||
25
|
36.1—361 Kg/h
|
40.3—403 Kg/h
|
44.6—446 Kg/h
|
48.8—488 Kg/h
|
53.1—531 Kg/h
|
|||||
32
|
59.1—591 Kg/h
|
66.1—661 Kg/h
|
73.1—731 Kg/h
|
80.0—800 Kg/h
|
87.0—870 Kg/h
|
|||||
40
|
92.4—924 Kg/h
|
103—1033 Kg/h
|
114—1142 Kg/h
|
125—1250 Kg/h
|
136—1359 Kg/h
|
|||||
50
|
0.14
|
1.44
|
0.16
|
1.61
|
0.18
|
1.78
|
0.20
|
1.95
|
0.21
|
2.12
|
65
|
0.24
|
2.44
|
0.27
|
2.73
|
0.30
|
3.02
|
0.33
|
3.30
|
0.36
|
3.59
|
80
|
0.37
|
3.69
|
0.41
|
4.13
|
0.46
|
4.57
|
0.50
|
5.00
|
0.54
|
5.44
|
100
|
0.58
|
5.77
|
0.65
|
6.45
|
0.71
|
7.14
|
0.78
|
7.82
|
0.85
|
8.50
|
125
|
0.90
|
9.02
|
1.00
|
10.09
|
1.12
|
11.15
|
1.22
|
12.21
|
1.33
|
13.28
|
150
|
1.30
|
12.99
|
1.45
|
14.52
|
1.61
|
16.06
|
1.76
|
17.58
|
1.91
|
19.12
|
200
|
2.31
|
23.09
|
2.58
|
25.82
|
2.85
|
28.55
|
3.13
|
31.26
|
3.40
|
33.99
|
250
|
3.61
|
36.08
|
4.03
|
40.34
|
4.46
|
44.61
|
4.88
|
48.85
|
5.31
|
53.10
|
300
|
5.19
|
51.95
|
5.81
|
58.09
|
6.42
|
64.23
|
7.03
|
70.34
|
7.65
|
76.47
|
350
|
7.07
|
70.71
|
7.91
|
79.07
|
8.74
|
87.43
|
9.57
|
95.74
|
10.41
|
104.1
|
400
|
9.24
|
92.35
|
10.33
|
103.3
|
11.42
|
114.2
|
12.50
|
125.0
|
13.59
|
135.9
|
450
|
11.69
|
116.9
|
13.07
|
130.7
|
14.45
|
144.5
|
15.83
|
158.3
|
17.21
|
172.1
|
500
|
14.43
|
144.3
|
16.14
|
161.4
|
17.84
|
178.4
|
19.54
|
195.4
|
21.24
|
212.4
|
600
|
20.78
|
207.8
|
23.24
|
232.4
|
25.69
|
256.9
|
28.14
|
281.4
|
30.59
|
305.9
|
DN
|
1.2 MPa
|
1.3 MPa
|
1.4 MPa
|
1.5 MPa
|
1.6 MPa
|
|||||
6
|
3.3—33.0Kg/h
|
3.5—35.5Kg/h
|
3.8—37.9Kg/h
|
4.0—40.3Kg/h
|
4.3—42.8Kg/h
|
|||||
8
|
5.9—58.7 Kg/h
|
6.3—63.1 Kg/h
|
6.7—67.4Kg/h
|
7.2—71.7 Kg/h
|
7.6—76.1 Kg/h
|
|||||
10
|
9.2—91.7 Kg/h
|
9.9—98.5 Kg/h
|
10.5—105.3 Kg/h
|
11.2—112.1 Kg/h
|
11.9—118.8 Kg/h
|
|||||
15
|
20.6—206 Kg/h
|
22.2—222 Kg/h
|
23.7—237 Kg/h
|
25.2—252 Kg/h
|
26.7—267 Kg/h
|
|||||
20
|
36.7—367 Kg/h
|
39.4—394 Kg/h
|
42.1—421 Kg/h
|
44.8—448 Kg/h
|
47.5—475 Kg/h
|
|||||
25
|
57.3—573 Kg/h
|
61.6—616 Kg/h
|
65.8—658 Kg/h
|
70.0—700 Kg/h
|
74.3—743 Kg/h
|
|||||
32
|
93.9—939 Kg/h
|
101—1009 Kg/h
|
108—1078 Kg/h
|
115—1147 Kg/h
|
122—1217 Kg/h
|
|||||
40
|
147—1468 Kg/h
|
158—1577 Kg/h
|
168—1685 Kg/h
|
179—1793 Kg/h
|
190—1901 Kg/h
|
|||||
50
|
0.23
|
2.29
|
0.25
|
2.46
|
0.26
|
2.63
|
0.28
|
2.80
|
0.30
|
2.97
|
65
|
0.39
|
3.88
|
0.42
|
4.16
|
0.44
|
4.45
|
0.47
|
4.73
|
0.50
|
5.02
|
80
|
0.59
|
5.87
|
0.63
|
6.31
|
0.67
|
6.74
|
0.72
|
7.17
|
0.76
|
7.61
|
100
|
0.92
|
9.17
|
0.99
|
9.85
|
1.05
|
10.53
|
1.12
|
11.21
|
1.19
|
11.88
|
125
|
1.43
|
14.34
|
1.54
|
15.40
|
1.65
|
16.45
|
1.75
|
17.51
|
1.86
|
18.57
|
150
|
2.06
|
20.64
|
2.22
|
22.17
|
2.37
|
23.69
|
2.52
|
25.21
|
2.67
|
26.74
|
200
|
3.67
|
36.70
|
3.94
|
39.42
|
4.21
|
42.12
|
4.48
|
44.82
|
4.75
|
47.53
|
250
|
5.73
|
57.34
|
6.16
|
61.59
|
6.58
|
65.81
|
7.00
|
70.03
|
7.43
|
74.27
|
300
|
8.26
|
82.57
|
8.87
|
88.69
|
9.48
|
94.77
|
10.08
|
100.8
|
10.69
|
106.9
|
350
|
11.24
|
112.4
|
12.07
|
120.7
|
12.90
|
129.0
|
13.73
|
137.3
|
14.56
|
145.6
|
400
|
14.68
|
146.8
|
15.77
|
157.7
|
16.85
|
168.5
|
17.93
|
179.3
|
19.01
|
190.1
|
450
|
18.58
|
185.8
|
19.95
|
199.5
|
21.32
|
213.2
|
22.69
|
226.9
|
24.06
|
240.6
|
500
|
22.94
|
229.4
|
24.64
|
246.4
|
26.32
|
263.2
|
28.01
|
280.1
|
29.71
|
297.1
|
600
|
33.03
|
330.3
|
35.48
|
354.8
|
37.91
|
379.1
|
40.34
|
403.4
|
42.78
|
427.8
|