State-of-the-art coating technology
SML pipes and fittings are supplied with a high quality, reddish brown epoxy coating

Since 1982, the cast iron socketless pipe system has completely replaced the socket drainage pipe. A tried-and-tested pipe material, easy to handle fittings and reliable couplings provide for a space-saving, fail-safe and durable pipe system, that fully meets the high demands of today’s living standards and state of-the-art technical building requirements. At the same time it fulfills many critical safety requirements such as sound insulation and fireproofing.

Due to the high level of quality of SML systems, these cast iron pipes are used for the most important sections of pipe systems in a building’s drainage system (downpipes, collecting pipes and rainwater drainpipes).


Our Product - Your Advantage

Not sensitive to heat and cold

Sturdy and dimensionally stable

Sound Protection

100% recyclable


No waste of resources

Fire Protection

High durability

Optimum corrosion protection

High abrasion resistance


Pipe internal coating

High quality from production to distribution

Long-term experience, well-educated staff and investments in modern production equipment enables us to produce cast-iron drainage systems for every requirement.

From the design with modern software to the finished product, we cover all steps in the production process, such as pattern building, core making shop, laboratory, automatic moulding machine, centrifugal line, coating technology.

Technical Datas

Nominal width
External diameter
External diameter
Wall thickness
Wall thickness
Insertion length
Pipe weight
Pipe weight
Permitted deviation
Pipes and fittings
permitted deviation
(sealing zone) 1
empty approx. kg/m
Full approx. kg/m
approx. m2 per m
+2 / -1
+2 / -1
+2 / -1
+2 / -1
+2 / -1
+2 / -2
+2 / -2
+2,5 / -2,5
+2,5 / -2,5
+2,5 / -2,5

SML Material Characteristics

approx. 7,2 kg/dm³
(71,5 kN/m³ )

Tensile strength
≥ 150 MPa for fittings
≥ 200 MPa for pipes

Compressive strength
approx. 3 to 4 times the value for tensile strength

Shear strength
approx. 1.1 to 1.6 times the value for tensile strength

Crushing strength
(peak compressive strength) ≥ 350 MPa

Modulus of elasticity
8•104 to 12•104 N/mm²

Poisson’s ratio

Coefficient of thermal conductivity
50-60 W/mK (at 20º C)

Heat resistance
As a system, PREIS® SML complies with fire resistance class A2 and cast iron itself is rated A1 according to EN 13501 – not combustible*

Coefficient of linear expansion
only 0.0105 mm/mK (between 0 and 100°C), more or less similar to concrete; can be set in concrete without any difficulty

Chemical resistance
PREIS® SML is highly resistant to domestic sewage water with a pH value of between 2 and 12

* Annex F.2 of EN-877 confirms:

“Cast-iron products in accordance with this European Standard are non flammable and not combustible. In case of fire they retain their functional characteristics and remain fire proof for a few hours, that is to say during this period their walls are impervious to flames and gases, they remain free from bursts and distortions, and they are failsafe. Wall and ceiling openings  remain intact.”

Sturdy and dimensionally stable

Tensile strength
Shear strength
Crushing strength
approx. 7,2 kg/dm3 (71,5 kN/m3)
> 150 MPa for fittings
> 200 MPa for pipes
approx. 3 to 4 times the value for tensile strength
approx. 1,1 to 1,6 times the value for tensile strength
(peak compressive strength) > 350 MPa

Cast iron is a fail-safe and durable material, dimensionally stable and sturdy.

SML Sound Protection


Sound insulation is one of the main advantages of FP PREIS® SML. Due to the high density of cast iron and the buffering effect of the rubber lining in the couplings, sound transmission is reduced to a minimum so that the system is able to ensure silent drainage. This provides the basis for general well-being in both, homes and offices, which is required by law and laid down in DIN 4109.


In December 2011, PREIS & Co conducted a sound insulation test according to DIN 4109 and EN 14366 at the renowned Fraunhofer Institute in Stuttgart, Germany. Standard FP PREIS® SML pipes and fittings where used for the tests along with the FP PREIS® Rapid couplings for connections and standard clamps for the wall fixing.
(See details on the right)
1 Downpipe support
2 Branch 88° DN100x100
3 Bracket
4 Rapid coupling
Arrangement of the drainage system, fixed to an installation wall with different pipe brackets (illustration not to scale, dimensions in mm).
Outline Fraunhofer Institute for Building Physics.
Sound level

The tests demonstrated that the cast iron drainage system with rapid couplings emits a very low level of noise as a freestanding syste. The crucial point in sound insulation lies in the pipe clamps for wall and ceiling installation, which is to say in the connections of the pipe system to the wall and / or ceiling.

If a vibration-decoupling element is used, the sound level can be reduced even more significantly until a sound level is reached that is not longer audible to the human ear.

The bottom row in the table below shows the sound level, if the downpipe is not attached to the wall – that is to say, it is installed independently. This test was carried out to isolate the airborne sound from the structure-borne sound.


The test focused on simulating common, real-life situations to show that those figures can be reproduced in a laboratory environment and in everyday installation on site.

FP PREIS® SML thus proved to be the best choice for fulfilling the provisions of sound protection using standard products without any additional, costly measures.

FP PREIS® SML in combination with:

Flow of water[litres per second]

Sound level on the ground floor (behind the wall- “GF rear”) in [db(A)]

Pipe clamp without rubber lining
Pipe clamp without rubber lining
Pipe clamp without rubber lining

If you need any further assistance with sound-insulation-planning, please contact our sales support.

100% Recycleable

Cast iron can be recycled in its properties.

It is important to stress that this is genuine recycling, not down cycling where products can be reused but have inferior properties compared to their original usage.

Assembly and installation instructions

PREIS® SML pipes, fittings and coupling systems are produced and inspected according to EN 877.

The SML pipes are cut to the required length directly by personnel working with the material. Pipes and fittings are joined with suitable pipe clamps.

Horizontal pipes have to be adequately fastened at all turns and branches. Downpipes have to be fastened at a maximum spacing of 2 m. In buildings with 5 floors or more, the downpipes of DN 100 or larger should be secured against sinking by means of a downpipe support. Additionally, for higher buildings, a downpipe support should be fitted at every subsequent fifth storey.

Drainage pipes are planned as unpressurised gravity flow lines. However, this does not exclude the pipe being under pressure if certain operating conditions occur. As drainage and ventilation pipes are subject to possible interactions between the pipes and their environment, they have to be permanently leak-tight against internal and external pressure of between 0 and 0,5 bars. To sustain this pressure, those pipe parts subject to longitudinal movement must be fitted along the longitudinal axis, properly supported and secured. This kind of fitting has to be used whenever interior pressure exceeding 0.5 bars arises in the drainage pipes, such as in the following cases:

  • Rainwater pipes
  • Pipes in the backwater area
  • Wastewater pipes which run through more than one basement without further outlet
  • Pressure pipes at wastewater pumps.

Non-friction-fitted pipelines subject to possible internal pressure or pressure developing during operation. These pipes must be provided with a suitable fixture, above all along the turns, to prevent the axes from slipping apart and separating. The required resistance of the pipe and fitting connections to longitudinal forces is achieved by installing additional clamps (internal pressure load up to 10 bars possible) at the joints.

Further information on technical issues can be found in our brochure for technical specifications and details.

PREIS® SML - no waste of resources

Genuine recycling, not down cycling!

A mixture of used car parts, construction waste and foundry return is the basis of our products. We recycle all scrap iron and production waste whenever possible. It is important to stress that this type of recycling does not affect the quality of our products, but lowers both energy consumption and CO2 emission of our foundries. 

SML Fire Protection

According to Annex H of EN 877 ( SBI – Single burning item Test) our PREIS® SML – drainage system in cast-iron was approved by the Austrian Research Institute for Chemistry and Technology (ofi) under the fire behaviour conferring conformity with the Construction Products Directive 89/106 EEC and confirmed the classification of A2 according to EN 13501.

In this test, a single pipeline (PREIS® SML pipes, fittings and Rapid-couplings) is mounted and a fire is simulated. The system is burned at about 700 °C for 20 minutes.


  • PREIS® SML drainage system is not flammable and non-combustible
  • In the event of fire,  no smoke is produced by the system
  • No burning or dropping material was determined due to the heat
  • The system retains the functional characteristics, the walls remain tight
  • The pipe system is absolute stable and intact (no chimney effect).

The excellent properties in structural fire protection were confirmed.

SML Standards

The following standards and regulations are relevant to PREIS® SML products:

  • EN 877 | Cast iron pipes and fittings, their joints and accessories for the evacuation of water from building. Requirements, test methods and quality assurance.
  • DIN 19522 | Complementary standard to EN 877. This standard mainly includes details about design and layout measures of pipes and fittings.
  • RAL-GZ 698 | RAL quality label demanding a notably extended test range and stricter requirements on quality, which goes far beyond the requirements of EN 877.
  • CE label | Declaration of conformity according to the European Directive for construction products (89/106/EEC).
  • EN 1561 | Standard for the founding of products made from grey cast iron with lamellar graphite.

SML Coating & Labelling

Coating technology for SML pipes and fittings

SML pipes and fittings are supplied with a high quality, reddish brown epoxy resin coating

The paint for fittings is applied as a dip coating with fully cross-linked epoxy resin coatings on the inside and outside of the piece, then to be heat-treated at 180°C for 45 minutes. This causes a compound to be built between the fitting and the coating which is of extra high strength, thus, providing the pieces with thermal and chemical resistance that goes far beyond the stringent requirements of EN 877 and RAL-GZ 698.

On the outside, SML pipes are coated with a reddish brown 40 µ-thick base coat g in accordance with DIN EN 877 that can be repainted with any standard colour varnish or finish commercially available. On the inside, the coating is sprayed with completely cross-linked ochre-coloured epoxy material (120 µ), thus protecting the pipe from aggressive domestic effluents.

Outside painting reddish brown corrosion protection 40u

Grey cast iron with lamellar graphite according to EN 1561

Inside painting epoxy coating 120u


Resistance of the inside coating of PREIS® SML pipes and fittings

For domestic facilities and discontinuous use

to 23° C
to 50° C
to 80° C
pH >1
pH1 (except for organic acids)
pH2 (except for organic acids)
Lime-scale dissolving agents
Cleaning agents
Stain remover
Water, salts
Drain cleaner


The quality of the inside coating is decisive for the durability of the drainage system. Increasingly aggressive domestic sewage water places high demands on the inside coating.

FP PREIS® SML pipes and fittings cover a wide range of use in the evacuation of water from buildings.


The benefits of PREIS® SML


Quick assembly with plug-in couplings.

SML GEG Quality Mark

Evidence of quality and safety given by the GEG quality label

This quality label from GEG is a guarantee for cast iron drainage systems you can continue to trust in the future. For quality assurance reasons, the “German Institute for Quality Assurance and Certification“ (RAL), Sankt Augustin, took the lead and founded the Gütegemeinschaft Entwässerungstechnik Guss e.V. (GEG – German Association for Drainage Technology Castings). Its main objective is to guarantee excellent product quality also for the future – documented by the quality label (RAL-GZ 698).

There are some suppliers who do not comply with the required quality objectives that have always been a relevant criterion for cast iron drainage pipes. The quality label takes into account the need for safety of all our partners, such as distributors, craftsmen, planning firms, or authorities. The quality label is awarded upon successful completion of an extensive initial test by independent, recognized test institutes. In addition, the test institutes conduct ad hoc external inspections at least twice a year to assure the quality of the products meets the stringent quality requirements.

These measures guarantee consistently high quality and spell out the great responsibility of manufacturers towards their partners in the market, for example distributors, fitters and end customers.

Requirements as of –>
EN 877
salt spraying
350 hours
1,500 hours
Resistance to waste water*
30 days at 23 °C
30 days at 50 °C
Chemical resistance
within a range of
pH 2 to pH 12,
30 days at 23°C
enhanced tests with
aggressive substances such
as phosporic acid (pH 1)

* For the typical composition of waste water see EN 877

Our history is our inspiration – Today, the PREIS Group employs more than 750 people at the productions sites in Austria, Slovenia, Croatia and Bosnia. The Group´s headquarter is located in Pernitz, Austria, and the company remains family owned. 

Our Vision -
Independent, stable and innovative!

Our assets!

The success story of the PREIS Group is based on responsibility, tradition and culture shared with both business partners and personnel.
Performance-orientated and innovative employees who are willing and able to accept responsibility are the main building block of our corporate culture. As a family-run company, we attach particular importance to satisfied employees who provide excellent support for our customers and partners through ongoing training and further education.

We offer exciting and demanding job opportunities in a variety of areas. Typical entry level positions in the PREIS Group are:

  • Apprentices (commercial, technical)
  • Worker – positions (Welder, Machine Operators, Iron Casting Workers)
  • Commercial positions in Sales, Logistics, Finance & Administration
  • Technical positions in Construction, Production, Research & Development
  • Leadership & Expert positions

We place great importance on continuity, stability, security and loyalty. A fair, co-operative partnership with our customers and suppliers and especially with our employees is our major focus.

Our financial stability gives us a high level of entrepreneurial freedom and the security of being able to bridge periods of economic instability. We reinvest our profits in structures, machines and equipment as well as in stable, attractive and healthy work places and in learning & development programs for our workforce.

We promote team-structures and team-work. Working together in cross-border project-teams is thus part of our corporate culture as is supporting departmental activities in the free time. The most important ambassadors, upholders and creators of our corporate culture are – besides our owner family – our leaders and our management.

Our leadership values are:

  • The managers are responsible for the continuous development of the company.
  • We value a friendly working environment and place great importance on job security and social values.
  • Our structures and processes are streamlined. We concentrate on the essential and execute this professionally.
  • Our management style is demanding and relies on communication.
  • We include our employees in decision making processes and implement decisions consistently and efficiently. 

Apply now

Go to our career page and send us an application for an open position, or send us an unsolicited application so we can get in contact with you. Please remember to describe which location and job would be attractive for you. We will forward your application to the proper personnel department and ensure a fast reply.

We look forward to receiving your application.