Method of Measure for Tubular Products

Home Tube Measure

Unless otherwise indicated, all wire loom, heat shrink, and braided sleeving is measured by the diameter of an open circle. While some companies may use the measurement of a flattened tube or the outer circumference, the industry standard is to measure tubing by nominal I.D. (interior diameter). To determine the appropriate diameter to purchase, bundle all of the wires together and measure this thickness. A caliper offers the most precise measurement, but laying a ruler against the wire bundle will also reveal the diameter.

Wire Loom

This versatile rigid tubing is convoluted to offer a flexible range of motion. Regardless if wire loom is slit or non-slit, it is always measured by an I.D. (interior diameter.) Unless otherwise indicated by spool/box sizes, wire loom is sold by the foot. Specify the length you require by adding the tubing into the shopping cart and then entering the number of feet for your purchase.

View conversion tables | View Wire Loom products

Heat Shrink Tubing

Heat shrink can be manufactured from many different materials to satisfy many different specifications. All of our heat shrink is measured by a before-shrinking I.D. (interior diameter). Each type of heat shrink follows a shrink rule: The most common rules are expressed as 2:1, 3:1, or 4:1.

2:1 – The tube diameter will shrink to one-half of the original size.
3:1 – The tube diameter will shrink to one-third of the original size.
4:1 – The tube diameter will shrink to one-quarter of the original size.

Unless otherwise indicated by spool sizes, heat shrink is sold by the foot. Specify the length you require by adding the tubing into the shopping cart and then entering the number of feet for your purchase.

Note: Shrinking may cause a change in length as well as diameter. Please calculate for this change in length. The width of the heat shrink wall will also increase after the shrinking these tubes.

View conversion tables | View Heat Shrink products

Braided Sleeving

This is another item that is almost exclusively measured by I.D. Some sleevings also have expansion and contraction ranges, but these measurements can vary greatly based on different materials and types of braid weave. Please note that the unique properties of some sleevings will be compromised if the recommended diameters are exceeded.

Unless otherwise indicated by spool sizes, braided sleeving is sold by the foot. Specify the length you require by adding the tubing into the shopping cart and then entering the number of feet for your purchase.

Expanding or contracting the diameter of any sleeving will have an affect on the length of that sleeving. Please calculate for this change in length.

View conversion tables | View Braided Sleeving products

AWG	Millimeter	I.D. Nominal	I.D. Maximum	I.D. Minimum
	0.5	0.020	0.024	0.018
24		0.022	0.027	0.020
22		0.027	0.032	0.025
20		0.034	0.039	0.032
	1.0	0.039	0.047	0.035
18		0.042	0.049	0.040
16		0.053	0.061	0.051
	1.5	0.059	0.067	0.055
15		0.059	0.066	0.057
14		0.066	0.072	0.064
13		0.076	0.080	0.072
	2	0.079	0.091	0.073
12		0.085	0.089	0.081
11		0.095	0.101	0.091
	2.5	0.098	0.110	0.093
10		0.106	0.112	0.102
	3	0.118	0.130	0.112
9		0.118	0.124	0.114
8		0.133	0.141	0.129
	3.5	0.138	0.149	0.132
7		0.148	0.158	0.144
	4	0.157	0.169	0.152
6		0.166	0.178	0.162
	4.5	0.177	0.189	0.171
5		0.186	0.198	0.182
	5	0.197	0.217	0.177
4		0.208	0.224	0.204
3		0.234	0.249	0.229
	6	0.236	0.256	0.217
2		0.263	0278	0258
	7	0.276	0.295	0.256
1		0.294	0.311	0.289
	8	0.315	0.335	0.295
5/16		0.323	0.334	0.313
0		0.330	0.347	0.325
	9	0.354	0.370	0.335
3/8		0.387	0.399	0.375
	10	0.394	0.411	0.370
7/16		0.450	0.3462	0.438
	12	0.472	0.532	0.453
1/2		0.512	0.524	0.500
	14	0.551	0.610	0.531
9/16		0.574	0.585	0.563
	16	0.630	0.689	0.610
5/8		0.640	0.655	0.625
	18	0.709	0.768	0.669
3/4		0.768	0.786	0.750
7/8		0.893	0.911	0.875
1		1.018	1.036	1.000

CONVERT MEASUREMENTS TO DIAMETER
If your company uses flat tube measurements or circumference measurements, please use the calculator below.
NOTE: These conversions are approximate and are most accurate for thin walled products. Greater wall thicknesses WILL slightly skew the true measure of diameter

Circumference input	Circumference/π = Diameter	Diameter output
Flat Tube input	2*Flat Measure/π = Diameter	Diameter output

CONVERT US Standard and Metric Measurement

mm input	mm/25.4=Inch	Inch output
cm input	cm/2.54=Inch	Inch output
Inch input	Inch*2.54=cm	cm output
Inch input	Inch*25.4=mm	mm output
cm input	cm*30.48=ft	ft output
m input	m/3.280840=ft	ft output
ft input	ft**3.280840=m	m output

CableOrganizer.com Method of Measure for Tubular Products