Tek-DP 1610D
Technology Solutions
*Note:
• The installation of thermometer pockets or wells will not alter the required minimum upstream straight
lengths for the other fittings.
• All straight lengths are expressed in multiples of diameter D.
• Values without parentheses are “Zero additional Uncertainty” values.
• Values in parentheses are “0.5% additional Uncertainty” values.
Table 1: Required Straight Lengths for Orifice Plate, Nozzle
Beta
Ratio
Upstream Side
of Primary Devices (U1)
Downstream Primary
Devices (D1)
Single 90
bend or
tee (Flow
from one
branch only)
Two or
0 more 90
bends in
the same
plane(*)
Two or
0 more 90
bends in
different
planes
Reducer
2D to D
over a
Length of
1.5D to 3D
Expander
0.5D to D
over a
Length of
D to 2D
Globe valve
fully poen
Full bore
ball valve
or gate valve
fully poen
Abrupt
symmetrical
reduction
having a
diameter
ratio >=0.5
Thermo-
meter
or well*) of
diameter
<=0.03D
Thermo-
meter
or well*) of
diameter
between
<=0.03D and
0.13D
Fitting
(All
mentioned
in Upstream
Side of
Primary
Devices)
0.20
10
(6)
14
(7)
34
(17)
5
16
(8)
18
(9)
12
(6)
30
(15)
5
(3)
20
(10)
4
(2)
0.25
10
(6)
14
(7)
34
(17)
5
16
(8)
18
(9)
12
(6)
30
(15)
5
(3)
20
(10)
4
(2)
0.30
10
(6)
16
(8)
34
(17)
5
16
(8)
18
(9)
12
(6)
30
(15)
5
(3)
20
(10)
5
(2.5)
0.35
12
(6
16
(8)
36
(18)
5
16
(8)
18
(9)
12
(6)
30
(15)
5
(3)
20
(10)
5
(2.5)
0.40
14
(7)
18
(9)
36
(18)
5
16
(8)
20
(10)
12
(6)
30
(15)
5
(3)
20
(10)
6
(3)
0.45
14
(7)
18
(9)
38
(19)
5
17
(9)
20
(10)
12
(6)
30
(15)
5
(3)
20
(10)
6
(3)
0.50
14
(7)
20
(10)
40
(20)
6
(5)
18
(9)
22
(11)
12
(6)
30
(15)
5
(3)
20
(10)
6
(3)
0.55
16
(8)
22
(11)
44
(22)
8
(5)
20
(10)
24
(12)
14
(7)
30
(15)
5
(3)
20
(10)
6
(3)
0.60
18
(9)
26
(13)
48
(24)
9
(5)
22
(11)
26
(13)
14
(7)
30
(15)
5
(3)
20
(10)
7
(3.5)
0.65
22
(11)
32
(16)
54
(27)
11
(6)
25
(13)
28
(14)
16
(8)
30
(15)
5
(3)
20
(10)
7
(3.5)
0.70
28
(14)
36
(18)
62
(31)
14
(7)
30
(15)
32
(16)
20
(10)
30
(15)
5
(3)
20
(10)
7
(3.5)
0.75
36
(18)
42
(21)
70
(35)
22
(11)
38
(19)
36
(18)
24
(12)
30
(15)
5
(3)
20
(10)
8
(4)
U2
14
18
31
7
15
16
10
15
3
10
