Threaded fittings - Technical Data
Steel type
Special steel threaded fittings are manufactured from steel of the following qualities:
- 1.4301
- 1.4541
- 1.4408 (316C)
- 1.4539
- 1.4462
- 1.4571
Threads in accordance with EN 10226-ISO 7-1 (former DIN 2999)
Our special steel threaded fittings are supplied with the thread in accordance with EN 10226, as a standard feature. This is also in line with standards SMS 295, BS 21, VSM 51100, DS8, SFS2118 and NS 983. All threads manufactured to this standard are conical on the outside and cylindrical on the inside. The abbreviation R indicates a conical exterior and the abbreviation Rp indicates a cylindrical inner.
Thread in accordance with ISO 228-1/Issue 2003
Special steel threaded fittings types 309 (nipple with parallel thread), 309SL Parallel nipple, 308Z Screwed end 308, 301Z, 307Z, 303 Z Elbow and tees, 327 (hexagon nut), 309, 327 Hexagon Nut, 340Z Hexagon Nipple, 331 (hexagon plug) 330Z Plug, are supplied with the thread in accordance with ISO 228 part 1, as a standard feature. All threads manufactured to this standard are cylindrical on the outside (abbreviation G) and cylindrical on the inside (abbreviation G).
NPT thread
Most of the special steel threaded fittings in the 300 range are also kept in stock with an NPT thread up to 3“ or can be produced at short notice when required. NPT thread stands for American National Standard pipe thread.
Pressure and temperature limits
Threaded fittings in the 300 range are manufactured from precision investment casting. We recommend the following according to pressure:
The pressure levels for the 400 range apply for items 334, 333, 308, 327, and 331.
| Dimensions NW | Inch | ND bei 20° |
| 6 - 50 | 1/8" - 2" | 16 bar |
| 65 - 100 | 2 1/2" - 4" | 12 bar |
| 125 - 150 | 5" - 6" | 10 bar |
| Dimensions NW | Inch | ND bei 20° |
| 6 - 50 | 1/8" - 2" | 50 bar |
| 65 - 100 | 2 1/2" - 4" | 50 bar |
| 125 - 150 | 5" - 6" | 40 bar |
Because assembly and welding are of vital importance for pressure resistance and imperviousness of a system, we recommend you carry out a pressure and leak test on site after installation. Please calculate higher pressures according to standard regulations.
Special quality items
Our special steel threaded fittings are always kept in stock in an exceptionally wide variety of materials. We are also willing to manufacture fittings with any of the special qualities you require, whether heat-resistant, nickel or titanium, and to the same high standards.
Custom-made items
Special steel threaded fittings are absolutely problem-free when it comes to making connections. If, however, you are unable to find parts which meet your exact requirements, please let us know what you need. Our production machinery can produce any of the fittings you need.
Delivery/acceptance
Fittings in the 300 range are delivered with a final inspection certificate in accordance with DIN 10204/2.1. The 400 range is delivered with a final inspection certificate in accordance with DIN 10204/3.1, and with ADW2 or 3.1C/A if required.
DIN standards
Threaded fittings are identified by DIN or the new EN DIN standards. These refer exclusively to the form and function of the parts. Dimensions are only partly in accordance with DIN standards. The data contained in our catalogue are binding in all cases.
Unions
May only be used as a complete unit. They can only be interchanged to a limited extent, due to the tolerances which are unavoidable in thread production.
