Coating Thickness Conversion Chart

Line Pipe
In the oil production process, line pipe is not just a tool to transport fluids, but also serve as additional support and stabilization for the well-bore.
This is why they are manufactured to endure high levels of pressure and to have maximum durability. Line pipe is commonly made of steel to ensure the reliability of the material in terms of strength and toughness.
Several tests are often conducted to make sure that the line pipe meet these requirements, thus enabling them to perform their function properly. Aside from these tests, the manufacturing process itself follows standards, some of which are set by the American Petroleum Institute (API).
Line Pipe Coating
One of the ways manufacturers make sure that the line pipe is of the best quality is to cover the steel pipe with a painted finish. Most line pipe is coated with the colors red or black. This colored protective coating can provide anti-corrosion properties and even thermal insulation for the external surface of the pipe. What is also important to note in purchasing coated line pipe is that different coatings have different thicknesses. Such is shown in the Coating Thickness Conversion Chart below.
Coating Thickness Conversion Chart
| wdt_ID | Micrometers (um) | Millimeters (mm) | Inches | Mils (Thousandths) | Tenths (Ten-Thousandths) | Millionths (Microinch) | Comments |
|---|---|---|---|---|---|---|---|
| 1 | 0.1 | 0.0001 | 0.000004 | 0.004 | 0.04 | 3.94 | |
| 2 | 0.5 | 0.0005 | 0.00002 | 0.02 | 0.2 | 19.69 | WS2 Coating |
| 3 | 1 | 0.001 | 0.000039 | 0.039 | 0.39 | 39.37 | |
| 4 | 1.5 | 0.0015 | 0.000059 | 0.059 | 0.59 | 59.06 | |
| 5 | 2 | 0.002 | 0.000079 | 0.079 | 0.79 | 78.74 | |
| 6 | 2.5 | 0.0025 | 0.000098 | 0.098 | 0.98 | 98.43 | |
| 7 | 3 | 0.003 | 0.000118 | 0.118 | 1.18 | 118.11 | PVD Coating |
| 8 | 3.5 | 0.0035 | 0.000138 | 0.138 | 1.38 | 137.8 | |
| 9 | 4 | 0.004 | 0.000157 | 0.157 | 1.57 | 157.48 | |
| 10 | 4.5 | 0.0045 | 0.000177 | 0.177 | 1.77 | 177.17 | |
| 11 | 5 | 0.005 | 0.000197 | 0.197 | 1.97 | 196.85 | |
| 12 | 5.5 | 0.0055 | 0.000217 | 0.217 | 2.17 | 216.54 | |
| 13 | 6 | 0.006 | 0.000236 | 0.236 | 2.36 | 236.22 | |
| 14 | 7 | 0.007 | 0.000276 | 0.276 | 2.76 | 275.59 | |
| 15 | 8 | 0.008 | 0.000315 | 0.315 | 3.15 | 314.96 | |
| 16 | 9 | 0.009 | 0.000354 | 0.354 | 3.54 | 354.33 | |
| 17 | 10 | 0.01 | 0.000394 | 0.394 | 393.7 | ||
| 18 | 12 | 0.012 | 0.000472 | 0.472 | 4.72 | 472.44 | |
| 19 | 15 | 0.015 | 0.000591 | 0.591 | 5.91 | 590.55 | |
| 20 | 20 | 0.02 | 0.000787 | 0.787 | 7.87 | 787.4 | |
| 21 | 25 | 0.025 | 0.000984 | 0.984 | 9.84 | 984.25 | |
| 22 | 25.4 | 0.025 | 0.001 | 1 | 10 | 1,000 | |
| 23 | 50.8 | 0.051 | 0.002 | 2 | 20 | 2,000 | |
| 24 | 76.2 | 0.076 | 0.003 | 3 | 30 | 3,000 | |
| 25 | 101.6 | 0.102 | 0.004 | 4 | 40 | 4,000 | |
| 26 | 127 | 0.127 | 0.005 | 5 | 50 | 5,000 | Thermal Spray Coating |
| 27 | 152.4 | 0.152 | 0.006 | 6 | 60 | 6,000 | |
| 28 | 177.8 | 0.178 | 0.007 | 7 | 70 | 7,000 | |
| 29 | 203.2 | 0.203 | 0.008 | 8 | 80 | 8,000 | |
| 30 | 228.6 | 0.229 | 0.009 | 9 | 90 | 9,000 | |
| 31 | 254 | 0.254 | 0.01 | 10 | 100 | 10,000 | |
| 32 | 304.8 | 0.305 | 0.012 | 12 | 120 | 12,000 | |
| 33 | 381 | 0.381 | 0.015 | 15 | 150 | 15,000 | |
| 34 | 508 | 0.508 | 0.02 | 20 | 200 | 20,000 | |
| 35 | 635 | 0.635 | 0.025 | 25 | 250 | 25,000 |
| wdt_ID | Micrometers (um) | Millimeters (mm) | Inches | Mils (Thousandths) | Tenths (Ten-Thousandths) | Millionths (Microinch) | Comments |
|---|---|---|---|---|---|---|---|
| 1 | 0.1 | 0.0001 | 0.000004 | 0.004 | 0.04 | 3.94 | |
| 2 | 0.5 | 0.0005 | 0.00002 | 0.02 | 0.2 | 19.69 | WS2 Coating |
| 3 | 1 | 0.001 | 0.000039 | 0.039 | 0.39 | 39.37 | |
| 4 | 1.5 | 0.0015 | 0.000059 | 0.059 | 0.59 | 59.06 | |
| 5 | 2 | 0.002 | 0.000079 | 0.079 | 0.79 | 78.74 | |
| 6 | 2.5 | 0.0025 | 0.000098 | 0.098 | 0.98 | 98.43 | |
| 7 | 3 | 0.003 | 0.000118 | 0.118 | 1.18 | 118.11 | PVD Coating |
| 8 | 3.5 | 0.0035 | 0.000138 | 0.138 | 1.38 | 137.8 | |
| 9 | 4 | 0.004 | 0.000157 | 0.157 | 1.57 | 157.48 | |
| 10 | 4.5 | 0.0045 | 0.000177 | 0.177 | 1.77 | 177.17 | |
| 11 | 5 | 0.005 | 0.000197 | 0.197 | 1.97 | 196.85 | |
| 12 | 5.5 | 0.0055 | 0.000217 | 0.217 | 2.17 | 216.54 | |
| 13 | 6 | 0.006 | 0.000236 | 0.236 | 2.36 | 236.22 | |
| 14 | 7 | 0.007 | 0.000276 | 0.276 | 2.76 | 275.59 | |
| 15 | 8 | 0.008 | 0.000315 | 0.315 | 3.15 | 314.96 | |
| 16 | 9 | 0.009 | 0.000354 | 0.354 | 3.54 | 354.33 | |
| 17 | 10 | 0.01 | 0.000394 | 0.394 | 393.7 | ||
| 18 | 12 | 0.012 | 0.000472 | 0.472 | 4.72 | 472.44 | |
| 19 | 15 | 0.015 | 0.000591 | 0.591 | 5.91 | 590.55 | |
| 20 | 20 | 0.02 | 0.000787 | 0.787 | 7.87 | 787.4 | |
| 21 | 25 | 0.025 | 0.000984 | 0.984 | 9.84 | 984.25 | |
| 22 | 25.4 | 0.025 | 0.001 | 1 | 10 | 1,000 | |
| 23 | 50.8 | 0.051 | 0.002 | 2 | 20 | 2,000 | |
| 24 | 76.2 | 0.076 | 0.003 | 3 | 30 | 3,000 | |
| 25 | 101.6 | 0.102 | 0.004 | 4 | 40 | 4,000 | |
| 26 | 127 | 0.127 | 0.005 | 5 | 50 | 5,000 | Thermal Spray Coating |
| 27 | 152.4 | 0.152 | 0.006 | 6 | 60 | 6,000 | |
| 28 | 177.8 | 0.178 | 0.007 | 7 | 70 | 7,000 | |
| 29 | 203.2 | 0.203 | 0.008 | 8 | 80 | 8,000 | |
| 30 | 228.6 | 0.229 | 0.009 | 9 | 90 | 9,000 | |
| 31 | 254 | 0.254 | 0.01 | 10 | 100 | 10,000 | |
| 32 | 304.8 | 0.305 | 0.012 | 12 | 120 | 12,000 | |
| 33 | 381 | 0.381 | 0.015 | 15 | 150 | 15,000 | |
| 34 | 508 | 0.508 | 0.02 | 20 | 200 | 20,000 | |
| 35 | 635 | 0.635 | 0.025 | 25 | 250 | 25,000 |
Coating Thickness Conversion Chart Abbreviations:
- µm – micrometer
- mm – millimeter
In the Coating Thickness Conversion Chart, what is shown is the conversion of one metric unit into another. For example, 0.1 micrometer is equal to 0.0001 millimeter. Basically, the Coating Thickness Conversion Chart simplifies the process of converting from one unit to another by providing common measurements one might see while purchasing line pipe. This is because while they belong to one industry, different manufacturing companies market their products with different units. Here, the Coating Thickness Conversion Chart comes in handy.
Coating Thickness Conversion Chart Units
In the Coating Thickness Conversion Chart, different units are measured:
- Micrometers
- Millimeters
- Inches
- Mils (one thousandth of an inch)
- Tenths (ten thousandth of an inch)
- Millionths (one millionth of an inch, also called as micro-inch)
Mils, “tenths”, and millionths, which are non-SI units (SI being the International System of Units), are also used and are common in describing the coating of the line pipe. Under the Comments column are the following descriptions for the pipe coating:
- WS2 coating is a tungsten disulfide coating
- PVD coating is Physical Vapor Deposition coating
Thermal Spray Coating refers to heated materials that are sprayed onto the surface
Ensuring Pipeline Longevity Through Proper Coating Thickness Selection
When selecting coated line pipe for oil and gas applications, understanding the precise thickness measurements and conversion factors presented in the Coating Thickness Conversion Chart is essential for ensuring optimal corrosion protection, thermal insulation, and long-term pipeline integrity. At FlowTech Energy, we offer a comprehensive selection of coated line pipe with various protective finishes and thickness specifications to meet diverse operational requirements across upstream, midstream, and downstream applications.
Our technical experts can help you navigate coating specifications across different measurement systems and manufacturer standards, ensuring you select the optimal coating thickness for your specific environmental conditions, fluid characteristics, and service life expectations. Contact us today at 1-877-645-6693 to discuss how our inventory of quality coated line pipe can provide the perfect balance of corrosion resistance, mechanical protection, and cost-effectiveness for your next pipeline project, maximizing both immediate installation success and long-term operational reliability in even the most challenging service environments.
Go here if you are looking for the Epoxy 2 Model Formulas Chart.


