Technical documents
Here find technical documents such as installation and operating instructions, certificates and information on our production tolerances.
If you have any further questions, please feel free to contact our team by phone or email.
Installation and operating instructions
Installation video for STAR electrofusion couplers and electrofusion fittings
Please observe the relevant operating and installation instructions during installation.
Product tolerances
All information on our website is provided without guarantee. In the interests of technical progress, we reserve the right to make changes and improvements without prior notice.
When producing our products, we comply with the relevant standards in terms of geometric dimensions, tolerances and quality requirements. For example, DIN EN 1555 is decisive for piping systems in the gas supply sector. In water supply, as well as for drainage and wastewater pressure pipes, DIN EN 12201.
If you require specific tolerances, please feel free to contact us.
You can receive a customized drawing with approval.
Tolerances for extension with pipe
d [mm] | Tolerance [mm] |
≤ 225 | ± 20 |
250 - 280 | ± 25 |
315 - 450 | ± 30 |
500 - 800 | ± 35 |
900 - 1200 | ± 40 |
1400 - 1600 | ± 50 |
≥1800 | on request |

Tolerances for extension with fittings
d [mm] | Tolerance [mm] |
≤ 315 | ± 10 |
315 – 500 | ± 15 |
> 500 | ± 20 |
Do you need specific tolerances for your assemblies?
Please feel free to contact us!

Tolerances for seamless bends
r / ri [mm] | Tolerance angles [α] | Tolerance z1 [mm] |
r ≈ 1,5 x d | ± 5° | ± 50 |
r ≈ 2,5 x d | ± 5° | ± 50 |
r ≈ 3 x d | ± 5° | ± 100 |
r ≈ 3,5 x d | ± 5° | ± 100 |
r ≈ 5 x d | ± 5° | ± 100 |
ri ≈ 700mm | ± 5° | ± 100 |
ri ≈ 1100mm | ± 5° | ± 100 |
ri ≈ 1750mm | ± 5° | ± 100 |

Tolerance for segment welded fittings
The following applies to the angles of segment welded fittings:
α = ± 2°

Tolerances for weights
The weights given in the technical product data sheets are for guidance only.
Please contact us for more precise calculations (statics, transportation, etc.).
Screw torques
The correct torque is essential for the safe and tight assembly of flange connections, as it prevents leaks, avoids damage to PE pipes, flanges or gaskets and ensures even load distribution to withstand pressure loads.
The following table lists the recommended screw torques from DVS guideline 2210-1. The values are permissible for all flange types. Due to the larger contact surface between the backing ring and plastic flange in the case of the KS flange and special flange connection, an excess of up to 30% is permissible for the aforementioned connections.

- for the assembly of flange connections using elastomer gaskets/ coefficient of friction, total µR = 0.15
- perm. p = permissible operating overpressure
(Source: DVS guideline DVS 2210-1 supplement 3 / page 6)
Download as PDF:
Pressure resistance for PE100 and PE100-RC
The pressure resistance of polyethylene (PE) pipe systems is determined by the pressure rating (PN - “Pression Nominale”) and the minimum wall thickness (SDR - “Standard Dimension Ratio”).
The specified operating pressures apply to an operating temperature of 20°C.
(* only valid for the Russian market)
SDR | S | PN Pipe | |
Diameter to wall thickness ratio | Pipe series | Water pressure max. operating pressure in bar | Gas max. operating pressure in bar |
41 | 20 | 4 | - |
33 | 16 | 5 | - |
26 | 12,5 | 6 | - |
21 | 10 | 8 | - |
17 | 8 | 10 | 5 |
13,6 | 6,3 | 12,5 | - |
11 | 5 | 16 | 10 |
9 | 4 | 20 | 12,5* |
7,4 | 3,2 | 25 | - |
Fittings with reduction factor
In addition to our pressure class-conform fittings , you also find fittings with a reduction factor (ƒB) in our range. These must be operated with a reduced pressure load.
The maximum permissible component operating pressure PFA (20° C water) is calculated using the formula PFA = PN × ƒB.
You can recognize our products with a reduction factor by the following symbols:

reduction factor 0,5

reduction factor 0,6

reduction factor 0,75
