General options
Special designs begin where a plant does not follow the standard face-to-face length. If the installation dimension is fixed, the medium runs hotter than usual or the design pressure exceeds the catalogue rating, we design the housing for it. The plant does not have to adapt to the strainer.
DN15 to DN1200
PN6 to PN40 · PN63 as special construction
EN 558-1 or made to measure
AD 2000 or EN 13445
A catalogue strainer is calculated for a fixed set of design parameters: face-to-face length to EN 558-1, the calculation pressure of the selected pressure rating and a design temperature at which the standard gasket and unalloyed steel remain permissible. If any of these parameters changes, the strength calculation changes. Wall thickness, flange pattern and cover closure follow directly. This cannot be solved with accessories.
With us, every strainer starts with the design engineering. From your specifications – installation dimension, calculation pressure and temperature, medium and fluid group, flow rate and required screen area – our design engineers derive wall thickness, shell pipe diameter, head type and connection design. You receive the draft for approval; only with the approved drawing does the order go into production.
Your own specifications are expressly welcome – drawings, specifications or the data sheet of the previous strainer. We incorporate them and revise the draft until it fits your plant.
The deviating design is therefore not retrofitted but engineered from the outset. We carry out the strength calculation to AD 2000 or EN 13445, and manufacturing is to the Pressure Equipment Directive 2014/68/EU – design, manufacturing and testing are all done in-house.
The following deviations are routine in our workshop. They can be implemented individually or in combination.
When an existing strainer is replaced, the line defines the dimension between the flanges. We build the housing to this dimension – the pipeline stays untouched. Special face-to-face lengths from around 200 mm to 1,250 mm are common.
The nominal size of the housing does not have to match the line. A larger housing increases the screen area and reduces the pressure drop, while the connection follows the line – for example a DN200 housing with a DN80 connection.
The standard design covers −10 to +50 °C. Above that, housing material and gasket set the limit: graphite with tanged steel insert instead of elastomer, heat-resistant steel instead of structural steel. T-type strainers are designed for up to +400 °C.
As standard, PN40 covers the vast majority of applications. Above that, we manufacture the high-pressure design up to PN63 – the higher rating also affects wall thickness, flange pattern and cover closure, which is why it is designed specifically.
Flat head instead of torispherical head where the overall height is limited. Inlet and outlet offset by 90° to each other where the line turns a corner. Additional sockets for differential pressure measurement at the position you specify.
As standard, the design is to AD 2000 and manufacturing to the Pressure Equipment Directive 2014/68/EU. If your project requires the EN 13445 design code or another code, we design to it.
The left column is the range we cover without separate review. The right column describes what goes beyond it – and what we need from you for it.
| Feature | Standard | Special construction |
|---|---|---|
| Dimensions | ||
| Nominal size basket strainer | DN50 – DN1000 | larger, up to DN1200 as special construction |
| Nominal size screens and blinds | DN10 – DN1200 | varies by type |
| Face-to-face length | EN 558-1 series 1 | any dimension to specification |
| Pressure and temperature | ||
| Pressure rating | PN6 – PN40 | PN63 as high-pressure design |
| Design temperature basket strainer | −10 … +50 °C | higher depending on material and gasket |
| Design temperature T-type strainer | −10 … +400 °C | stainless steel screen plate |
| Design temperature pot type strainer | up to +150 °C | depending on pressure |
| Design and verification | ||
| Calculation basis | AD 2000 | EN 13445 design code on request |
| Manufacturing | PED 2014/68/EU | other codes by agreement |
| Material certification | EN 10204-3.1 | further certificates possible |
The more complete this information, the sooner the draft is ready. Existing drawings or specifications replace part of it – simply send them along.
| Information | Unit or format |
|---|---|
| Installation dimension | Distance between the flanges in mm |
| Nominal size and standard | DN or inches, DIN or ANSI |
| Design pressure | bar, not just the operating pressure |
| Design temperature | °C, with minimum and maximum |
| Information | Unit or format |
|---|---|
| Medium | Name and fluid group |
| Flow rate | m³/h or l/min |
| Mesh size | in mm, additionally in µm |
| Code | AD 2000, EN 13445 or your specification |
An existing strainer is replaced, but the pipeline stays as it is. Then only one thing counts: the new strainer must fit the existing dimensions – including flange pattern, installation length and connection height. Send us the old data sheet or a dimensioned photo; we design the replacement from it. If you are replacing anyway, it is worth checking whether a larger housing would extend the service life.
Yes. Before production starts, you receive the design draft for approval. Only once you have confirmed it does the order go into manufacturing. We incorporate any requested changes beforehand.
Certainly. Drawings, specifications, parts lists or the data sheet of the previous strainer are the best basis. Our design engineers adopt your specifications and adapt them where manufacturing or the code requires – we agree any deviations with you in advance.
The regular range goes up to DN1000. Larger housings up to DN1200 are manufactured as special construction. It is not only the shell pipe that gets larger: cover weight, lifting device and support legs must also be designed accordingly.
Standard is PN6 to PN40. In strainer manufacturing, PN40 is already the high-pressure range and covers most applications. As a high-pressure design we manufacture up to PN63 – wall thickness, flange pattern and cover closure are then redesigned together.
The operating pressure is the pressure in normal operation; the design pressure is the value the housing is calculated for – including a reserve for pressure surges and start-up. The second value is decisive for the design.
This is not decided by the strainer but by the combination of material and gasket. Elastomer gaskets set an early limit, graphite with tanged steel insert a much later one. T-type strainers are designed for up to +400 °C. Tell us the design temperature – we select material and gasket to suit.
Yes. Standard is AD 2000; the EN 13445 design code is also possible. In both cases, manufacturing is to the Pressure Equipment Directive 2014/68/EU.
Yes, and this is often the better solution. A larger housing provides more screen area, reduces the pressure drop and extends the time until cleaning – the connection still follows the line.
We calculate each design individually and show the deviating item separately in the quotation. This makes clear which part of the price is attributable to the special design – a different face-to-face length has a different effect than a higher pressure rating, which changes wall thickness and flange pattern at the same time.
All topics at a glance: Strainer options and accessories
Installation dimension, design pressure, design temperature and medium are enough for the first draft. If an old data sheet is available, it is even quicker.
