Icons - Overview


With the icon "media" as customers you can recognize the suitability of hoses for specific medias at a glance. This icon "media" distinguishes between gaseous, liquid and fine dust medias as well as solids and heavy loads. This innovative icon enables customers to instantly select the right hose or hose system.

Gas: for all hoses which are suitable for gaseous media.

Dust: for all hoses which transport powdery media.

Liquid: for all hoses which transport liquid media.

Solids: for all hoses which transport solids.

Raw Material Pre-PUR®

Polyurethanes are not all the same!

As with all raw materials and finished goods, there are large differences in quality here as well.

For many of its hoses, NORRES uses a special mixture called Pre-PUR®, containing an ester-polyurethane or an ether-polyurethane.

Compared to many other plastics, rubber formulations and “simple” polyurethanes, the block copolymers, which consist of hard and soft Pre-PUR® segments, have superior properties. The hard segments of Pre-PUR® provide extremely high mechanical stability, while at the same time the soft segments give the material high flexibility and dynamic load capacity.

Our hoses made from Pre-PUR® raw materials differ as follows from many of the hoses commercially available:

  • NORRES Pre-PUR® consists of special and high-quality, premium ester- and ether-polyurethanes.
    Choosing a polyurethane just one level of quality lower can cause a reduction of more than 30% in abrasion resistance.
    The use of high-purity raw materials and a narrow tolerance range ensure a high level of quality.
    • excellent mechanical stability
    • low abrasion
    • excellent chemical and hydrolytic resistance
  • NORRES Pre-PUR® has extremely long molecular chains (high molecular weight and a lot of crystalline domains and morphology).
    During chemical, hydrolytic and thermal degradation, molecular chains are generally shortened as a result of chain scission. Consequently, longer molecular chains generally result in longer service life. The length of the molecular chains is also a determining factor in the softening point of a hose. Thus products made from Pre-PUR® have above average residual strength when subjected to heat, while at the same time demonstrating better flexibility at low temperatures.
    • improved chemical and hydrolytic stability
    • higher softening points
    • greater residual strength at high temperatures
    • higher compression strength
    • greater safety due to material stability
    • better hot air aging properties
    • better low temperature flexibility
    • lower “bending force” when cold
    • lower risk of bending fracture at low temperatures
  • NORRES Pre-PUR® contains special stabilizers for hose technology, developed in partnership with our raw material suppliers. Without these additives, hoses generally are more vulnerable to chemical, hydrolytic and thermal attack and occasionally wear out significantly faster.
    • improved chemical and hydrolytic stability
    • improved oxidation resistance
    • better hot air aging properties
    • improved resistance to weathering

The ether-polyurethane Pre-PUR® used in many of our hoses has the following advantages over ester-polyurethane Pre-PUR® (and also over other ester-polyurethanes):

  • Resistant to microbes (This is critical for extended contact with soil or similar substances or heavy contamination under conditions favourable to microbes. The chemical structure of ether-polyurethanes gives the materials permanent resistance to microbial attack. We believe this is clearly a better solution than ester-polyurethanes that are often stabilized with for health not completely harmless additives for this purpose. With these ester-polyurethanes there is a risk that the additive will leach out, causing the level to fall below that required for protection as the additive migrates to the surface of the hose and comes in contact with the user and the material transported.)
  • Resistant to hydrolysis (This is critical for wet applications at higher temperatures and for use in tropical climates.)
  • Its chemical stability is far superior to ester-polyurethanes
  • Its flexibility at low temperatures is superior to comparable ester-polyurethanes

In summary:

  • longer service life
  • greater safety
  • significant added value and greater benefits

The particularly high quality mixtures of PUR materials, as well as the optimized, reinforced hose designs from NORRES, result in substantially less wear in pumping and transport processes than with many other hoses. These NORRES hoses are specially developed for long service life for the delivery of highly abrasive media. Compared with similar grades of hose, they are distinguished by a number of special characteristics, including:

  • Selective reinforcement of the wall geometry at the primary points of wear. We consistently achieve surprisingly high service life for our hoses through continual optimization of their design geometries.
  • Very high temperatures can occur in certain applications due to friction from the pumped medium. Thermoplastic synthetic materials soften at higher temperatures, leading to a loss of strength and increased abrasion. In vacuum operation this leads to an pronounced axial contraction, an increase in the rippling of the interior wall and thus a further increase in abrasion.
    NORRES uses material mixtures with high dimensional stability at high temperatures for polyurethane hoses intended for these applications.
  • The profile geometries of NORRES PUR hoses are optimized to give the products outstanding axial stiffness while maintaining excellent flexibility. Less interior rippling in vacuum applications means longer service life.

These hoses are made from raw materials with particularly high mechanical strength and special additives resulting in:

  • Very high abrasion resistance
    → less wear
    → long service life
  • very high tensile strength
    → less change in the axial length of the hose during the application
    → less interior rippling of the hose due to change in length
    → long service life
  • Additional reductions in wear due to the special additives

NORRES hoses with this symbol are specially designed for workshop use and laying on floors. They are able to resist crushing to some extent or entirely when driven over or stepped on. Please refer to the relevant product description for more details.

Below is a selection of our products that have the product quality icon "Crush resistant":

Interior smoothness

Many hoses from NORRES have outstanding interior smoothness and are thus optimized for flow. They have the following advantages:

  • Very high delivery rates
  • Low pressure loss
    → reduction of blower power requirements
    → lower operating costs
  • Gentler material delivery
  • Low wear and therefore longer service life

Below is a selection of our products that have the product quality icon "Smooth interior":

High flexibility

This symbol is only used for NORRES hoses that are highly flexible and have the following characteristics:

  • Minimal counterforce and restoring force when bent
  • Optimal for applications such as suction arms

Below is a selection of our products that have the product quality icon "High flexibility":


Not all plastic materials and qualities could withstand microbes. This is critical for extended contact with soil or similar organic substances or heavy contamination under conditions favorable to microbes. The chemical structure of this material is modified for resistance to microbial attack.

Below is a selection of our products that have the product quality icon "Microbe resistant":

Approvals for use with foodstuffs

NORRES hoses with this symbol have one or more national and/or international approvals and certifications of conformity that allow them to be used in food applications. Please refer to the relevant product description for more details.

Below is a selection of our products that have the product quality icon "Food":

Flame retardant

NORRES hoses with this designation have one or more national and/or international approvals classifying them as having low flammability or as self-extinguishing and/or fall below specified rates of burning.

Below is a selection of our products that have the product quality icon "Flame retardant":

Partially coloured

Strengthen your market position by consistent application of your corporate design and differentiate yourself from the competition. Create a unique “look” to secure after-sales business and reduce product liability risks with an unfalsifiable appearance.

Using a patented production method, AIRDUC® and PROTAPE® hoses can also be coloured in the bead area according to your specifications. Compared with completely coloured hoses, the partially coloured design makes the impression of a significantly more flexible, lighter product. Moreover, as with transparent hoses, it is possible to observe processes directly.

Antistatic or electrically conductive hoses

According to the new ATEX guideline and the German TRGS 727, electrically conductive hoses should be used in areas where the danger of explosion exists. Products of this type are distinguished by a special symbol.

Please refer to the relevant product description for more details and the technical appendix.

Below is a selection of our products that have the product quality icon "Antistatic and electrically conductive hoses":

Special wire adhesion

Many hose types are designed with the spring steel wire firmly embedded in the wall. This strong adhesion is a key prerequisite of the product’s stability, resistance to overpressure and axial stiffness, which in turn have an important influence on hose service life. The operating conditions, for example oils or solvents diffusing into the wall, a combination of mechanical and dynamic loads and especially high or low temperatures, frequently represent a formidable obstacle to achieving permanent adhesion between the spring steel wire and the wall.

Our longstanding experience has taught us that detached wires provoke increased and asymmetric rippling of the hose, usually resulting in a significantly shorter service life, substantially higher pressure losses and long-term disruptions to the delivery process.

Hoses manufactured using our special, highly advanced, multistage adhesion process are marked with this symbol. The exceptionally long service life realised with these products – even when subjected to severe combined loads – would otherwise remain unattainable.

Cut Lenghts

NORRES provides excellent service to customers which includes cutting services on many NORRES hose products that are in stock. This added benefit can be utilized for a small fee to provide you with the hose length that suits your needs when production time is not an option.

Below is a selection of our products that have the product quality icon "Cut lengths":

NORRES 24/48 Hour Shipment Service

Products with the NORRES “24 hour” (“48 hour”) icon leave NORRES or a NORRES branch within the time specified based on the defined wall thickness of the hose.

Below is a selection of our products that have the product quality icon "24/48 hour shipment service":

NORRES 48 Hour Assembly Service

NORRES assembles the items marked with the "48 hour" icon within this time frame (max. of 10 pieces per order).

Below is a selection of our products that have the product quality icon "48 hour assembly service":

Glass/ fork symbol EU food approval

For those hoses which include the EU’s official food logo – the glass / fork symbol – exists an official approval for each complete hose by an independent testing laboratory in accordance with the newest EU Directive 10/2011 as well as the supplementary Regulation 2015/174.

Analyses carried out by an independent testing laboratory show that these product series meet the requirements of the EU Directive 10/2011 “Synthetic materials and articles intended to come into contact with food” and the German Regulations on Commodities for food contact materials.
Please note the official test certificate.

Below is a selection of our products that have the product quality icon "EU food approval":

Permanently antistatic

In the past, hoses with antistatic properties were generally manufactured using an additive that migrated over time, so that the material’s antistaticness was gradually lost. The desired antistatic properties could often only be guaranteed if the ambient air was sufficiently humid.

Thanks to a novel, innovative material from NORRES, all hoses marked with this symbol are permanently antistatic. Their antistatic properties are not dependent on the relative humidity nor does their effect deteriorate due to migration.

Below is a selection of our products that have the product quality icon "Permanently antistatic":


NORRES is one of the leading trendsetters and manufacturer of high-quality technical hose systems. A variety of NORRES hoses and systems have the characteristic "patented icon" and thus offers NORRES partners and customers unique products and solutions in the field of technical hoses. Customers and partners can identify patented hoses with the NORRES Patented Icon at a glance.

Below is a selection of our products that have the product quality icon "Patented":


Continuous operating temperatures of 125°C are often demanded of the hoses used in plastics production or on printing presses and compressors. NORRES has developed a new polyurethane type based on the premium polyurethane Pre-PUR® that is more resistant to heat and less susceptible to ageing than other materials.

The polymer is cross linked by NORRES in an innovative process to create a material that shows a 40 percent improvement in mechanical stability during heat exposure. NORRES hoses with the HT-PUR symbol can be heated to a continuous operating temperature of 125°C and withstand peaks of up to 150°C.

Advantages of HT-PUR hoses at a glance:

  • Longer service life
  • Less wear
  • High compressive strength at higher temperatures
    → Lower operating costs
  • Good resistance to chemicals, oil and petrol
  • Lighter, more flexible and cheaper than other materials such as metal
  • Capable of electrostatic discharge

The following products have the product quality icon "HT-PUR":


NORRES hoses with this symbol are 100% free of phthalate softener.

Below is a selection of our products that have the product quality icon "Free of phthalate":