# Pipe And Tube Sizing Guide

Pipe and Tube Sizing Guide
Directions: Measure your pipe using one of the methods to the
right. Find the measurement below that is closest to yours and
follow the chart across to find your pipe or tube size. If your
row has both a pipe size and a tube size, pick either one; the
Measuring Circumference
actual insulation will be the same.
Outside
Circumference
Diameter
Pipe Size
Tube Size
1 1/4
3/8
1/8
1/4
1 5/8
1/2
1/4
3/8
2 1/8
5/8
3/8
1/2
2 3/8
3/4
5/8
2 3/4
7/8
1/2
3/4
Circumference is the distance it
3 1/4
1
3/4
takes to go around the pipe once.
If you have a cloth tape measure,
3 1/2
1 1/8
1
wrap the tape around the pipe
4 1/4
1 3/8
1
1 1/4
once and measure to the nearest
5 1/8
1 5/8
1 1/4
1 1/2
1/8 of an inch. Alternatively, you
6
1 7/8
1 1/2
can wrap a string (or paper or
6 5/8
2 1/8
2
similar) around the pipe once, mark
7 1/2
2 3/8
2
the length, and lay flat on a ruler
8 1/4
2 5/8
2 1/2
and measure the length.
9
2 7/8
2 1/2
9 7/8
3 1/8
3
11
3 1/2
3
11 1/2
3 5/8
3 1/2
Measuring Outside Diameter
12 5/8
4
3 1/2
13
4 1/8
4
14 1/8
4 1/2
4
16 1/8
5 1/8
5
17 1/2
5 5/8
5
19 1/4
6 1/8
6
20 7/8
6 5/8
6
27 1/8
8 5/8
8
33 3/4
10 3/4
10
40
12 3/4
12
Outside diameter is the farthest
44
14
14
distance across the pipe. We only
recommend using this method
50 1/4
16
16
with a caliper (shown above) or
56 1/2
18
18
similar measuring device that can
62 7/8
20
20
take an accurate reading across the
69 1/8
22
22
pipe. Measuring across the pipe,
75 3/8
24
24
find the outside diameter to the
81 5/8
26
26
nearest 1/8 of an inch.
88
28
28