Technical resources
Reference only, confirm against your project specificationThe tables buyers and engineers ask us for most often, plus the checklist that turns a vague enquiry into a quotation we can price the same day.
Pipe weight calculator
Theoretical weight per metre for round metallic pipe, from outside diameter, wall thickness and density.
Indicative only. Confirm against the governing standard and the manufacturer data before ordering.
Werkzwise 2026 Catalogue
Product categories, material range, quality information, manufacturer references and contact details in one document.
Pipe wall thickness
Nominal outside diameter and wall thickness in millimetres for common schedules, to ASME B36.10M and B36.19M.
| Size | OD mm | SCH 40 | SCH 80 | SCH 160 |
|---|---|---|---|---|
| 15 NB (1/2") | 21.3 | 2.77 | 3.73 | 7.47 |
| 25 NB (1") | 33.4 | 3.38 | 4.55 | 9.09 |
| 50 NB (2") | 60.3 | 3.91 | 5.54 | 11.07 |
| 80 NB (3") | 88.9 | 5.49 | 7.62 | 15.24 |
| 100 NB (4") | 114.3 | 6.02 | 8.56 | 17.12 |
| 150 NB (6") | 168.3 | 7.11 | 10.97 | 21.95 |
| 200 NB (8") | 219.1 | 8.18 | 12.70 | 22.23 |
| 250 NB (10") | 273.0 | 9.27 | 15.09 | 25.40 |
| 300 NB (12") | 323.8 | 10.31 | 17.48 | 25.40 |
Flange pressure classes
Indicative working pressure in bar for ASME B16.5 group 2.2 materials at three temperatures.
| Class | at 38 °C | at 200 °C | at 400 °C | Typical use |
|---|---|---|---|---|
| Class 150 | 19.6 | 15.8 | 10.2 | Utility and low pressure process |
| Class 300 | 51.1 | 41.4 | 27.4 | General process piping |
| Class 600 | 102.1 | 82.7 | 54.9 | Higher pressure hydrocarbon service |
| Class 900 | 153.2 | 124.1 | 82.3 | High pressure gas and injection |
| Class 1500 | 255.3 | 206.8 | 137.2 | Wellhead and high pressure systems |
| Class 2500 | 425.5 | 344.7 | 228.6 | Extreme pressure applications |
Bolting selection
Stud and nut combinations used on flanged joints, with the service they are normally specified for.
| Stud / nut | Description | Service |
|---|---|---|
| A193 B7 / A194 2H | Alloy steel, the standard flange bolting set | -46 to 427 °C |
| A193 B7M / A194 2HM | Hardness controlled for sour service | NACE MR0175 |
| A320 L7 / A194 7 | Low temperature service | Down to -101 °C |
| A193 B8M Class 2 / A194 8M | 316 stainless, strain hardened | Corrosive and cryogenic |
| Duplex S31803 / S32750 | High strength, chloride resistant | Offshore and seawater |
What to send us
Missing half of these is normal. Send what you have and we will come back with the questions that actually affect the price, rather than a form to fill in.
Need a datasheet or a catalogue?
Ask for the product line you are working on and we will send the current documentation directly.