Offshore product range: pipes, fittings and flanges

KME’s division Marine Applications specializes in the production and supply of copper-nickel alloys for seawater piping system. Since decades, these alloys have successfully used in:

  • Merchant and military shipbuilding

  • Offshore oil and gas installations

  • Coastal petroleum and petrochemical processing plants

  • Seawater desalination plants

  • Coastal electricity generation plants

Copper-nickel alloys are widely applied in:

  • Seawater cooling systems

  • Fire water systems

  • Sanitary systems

  • Deck steam pipes

  • Hydraulic and pneumatic systems

  • Seawater feed lines to desalination and processing units

  • Splash zone cladding

Properties and advantages of OSNA®10-Alloy

KME OSNA®10-Alloy

The chemical composition of the KME’s OSNA®10-alloy is modified to ensure the compliance with all international specifications. Controlled content of alloying elements and minimised concentration of impurities ensure reliable service and fabrication properties of the alloy.

Main Advantages of OSNA®10-Alloy

Despite the rough conditions in marine service and the highly corrosive nature of seawater, the products provide well balanced combination of technical and economical advantages:

  • Simple alloying system with good weldability

  • Excellent ductility and toughness

  • Outstanding erosion corrosion performance

  • Resistant to uniform and localised corrosion

  • No effect of ambient seawater temperatures

  • No effect of seawater chlorination

  • Resistant to biofouling

  • Resistant to stress-corrosion cracking

  • Low maintenance costs

  • A lot of design experience

Comparison of Standard Specifications for OSNA®-10 (CuNi 90/10)

KME Alloy DIN CEN/TS DIN 86019 BS 2871(1) DIN EN 12449 EEMUA MIL-T- 16420K JIS H 3300
  OSNA®-10 13388 WL 2.1972 CN 102   144-1987 ASTM B 466(2) C 7060 T
 (CuNi 90/10)CW352H   UNS C 7060 xC 70620 
Ni % 10.0 - 11.0 9.0 - 11.0 9.0 - 11.0 10.0 - 11.0 9.0 - 11.0 10.0 - 11.0 9.0 - 11.0 9.0 - 11.0
Fe % 1.5 - 1.8 1.0 - 2.0 1.5 - 1.8 1.0 - 2.0 1.0 - 2.0 1.5 - 2.0* 1.0 - 1.8 1.0 - 1.8
Mn % 0.6 - 1.0 0.5 - 1.0 0.5 - 1.0 0.5 - 1.0 0.5 - 1.0 0.5 - 1.0 max. 1.0 0.2 - 1.0
C % max. 0.02 max. 0.05 max. 0.05 max. 0.05 max. 0.05 max. 0.05 max. 0.05  
Pb % max. 0.01 max. 0.02 max. 0.01 max. 0.01 max. 0.02 max. 0.01 max. 0.02 max. 0.05
S % max. 0.005 max. 0.05 max. 0.005 max. 0.05 max. 0.05 max. 0.02 max. 0.02  
P % max. 0.02 max. 0.02 max. 0.02   max. 0.02 max. 0.02 max. 0.02  
Zn % max. 0.05 max. 0.50 max. 0.05   max. 0.50 max. 0.20 max. 0.50 max. 0.50
Sn %   max. 0.03     max. 0.03      
other imp. max. 0.20 max. 0.20 max. 0.20 max. 0.30 max. 0.20 max. 0.30    
Cu % rem. rem. rem. rem. rem. rem. rem. +Ni+Fe+Mn
                min. 99.5

(1)  no longer valid

(2)  equal to C 70600 for subsequent welding

*    the iron content has been specified to improve corrosion resistance

The OSNA®10 offshore product range is based on:

  • EEMUA –144: 1987 Tubes Seamless and Welded ("pipes" in this web site)

  • EEMUA –145: 1987 Flanges Composite and Solid

  • EEMUA –146: 1987 Fittings

The unique dimensional range from ½ inch to 36 inch ensures the supply of the entire piping systems from one source. Although the pipe dimensions of 38 and 40 inch are not included in the EEMUA 144 – 1987 they are available here as they are commonly specified in offshore projects. Based on ASME specifications, additional components are included.

Design Scope

Working pressures and temperatures of components included in this specification

  • 1. 16 bar/232 psi: -29°C/-20°F to +75°C/+167°F

  • 2. 20 bar/290 psi: -29°C/-20°F to +38°C/+100°F

Pipes Seamless and Welded

Pipes are based on BS MA 60, DIN 86007, and ANSI/ASME B31.3The wall thicknesses comply with ANSI B31.3 and DIN 86007 as well as International Association of Classification Societies with additional allowances for robustness to withstand mechanical damage, especially in the smaller sizes. The fit-for-purpose corrosion allowance of 0.5 mm sufficient for entire service life of the piping installation has been included. This corrosion allowance is in accordance with all major classification societies specified for alloys containing ≥10 wt. % Ni and ≥1.5 wt. % Fe. Read more on mechanical properties of pipes.

Flanges Composite and Solid

Included series of composite (lap type) and solid flanges in metric dimensions based on ANSI B16.5, MSS SP-44 and BS 1560

The basic metric dimensions for drilling and flange outside diameters are those given in ANSI B16.5 and MSS SP 44 Class 150 rating with inch size bolting.

The copper-nickel stub end and flange joint faces are machine finished and comply with the corresponding Sections of EEMUA 145 (Read more).


The specification comprises a series for pipe fittings including butt weld, socket welding, capillary brazing, threaded, selfreinforced fittings as well as saddle pieces.

The “building in” dimensions of the butt welding fittings are based on ANSI B16.9 apart from the caps that are based on DIN 28011 (with suitable amendments).

Physical Properties of CuNi 90/10

The basic allowable stresses in tension are in accordance with ASME B31.3 Table A-1.


The welding consumables used for the manufacturing of welded components are in accordance with AWS-A5.7 Class ER CuNi. The welding procedure specification and welder qualification are in accordance with ASME code, section IX.

Testing of Welds

The weld seams are examined by the liquid dye penetrant testing in accordance with ASME code, section VIII, division 1, appendix 8. The radiographic examination is performed for the complete length of each weld to meet the requirements of ASME code, section VIII, UW51.


The gaskets normally used with flanges are those made from aramid fibre with nitrile binder in accordance with ASME B16.21 or equivalent. The gasket hardness shall not be less than 75 Shore. The gaskets shall not be graphited. In order to ensure adequate seating when solid weldneck and solid slip-on flanges are used, irrespective of gasket materials, the gaskets shall be located within the bolt circle. Note: Gaskets should not be used when mating with elastomerlrubber faced flanges.


The majority of components included in this catalogue are available in the PDMS-format. Please contact us for more information.