CRN78T -EI435

International Equivalent

Mark Analogue W. Nr. Aisi Uns En Order
ХН78Т EI435 2.4630 N06075 NiCr20Ti Delivery from the stock, in stock

Relevance

Steel CrN78T refers to high-temperature resistant grades, thanks to the high content of nickel, which forms on the surface of a strong oxide film, the presence of which is stipulated by GOST 14 162-79. At t ° 1100 ° C, the rate of oxidation is 0.2 mm per year. CrN78T is used for the production of low loaded parts operating at up to 1100 ° C. One of the disadvantages of CrN78T is its instability in environment of sulfur compounds which leads to embrittlement.

Chemical composition of CrN78T alloy (in %)

Ni Cr Fe Ti Si Mn С P S
70,003-80,85 19-22 up to 6 0,15-0,35 up to 0.8 up to 0.7 up to 0.12 0,015 0,012

Alloy CrN78T is widely used by modern industry. It serves as a basis for manufacturing of capillary tubes - thin-walled tubes of minimum diameter, characterized by low weight and high strength. As a rule, they have circular or, less frequently, profiled cross-section: rectangular, square or oval. They are indispensable in the aviation, machine-building, oil and gas industry and in medicine.

Tube Production

Outer diameter (in mm) Wall thickness (in mm). Tube length Regulation
0,3 - 120 0.08 - 5 short (0,3m - 7m), dimensional (4 - 7m), multiple of dimensional (over 4m with 5mm allowance), in coils (up to 160 m), tubing (up to 160 m), wall thickness (over 4m) A normalization of mechanical properties and chemical composition; B normalization only of the chemical composition; C normalization only of mechanical properties.

Production .

Tolerances: if the inner diameter is 0,6 mm or more, the tolerances of the inner diameter must not exceed the outside diameter tolerance of the tube by more than 0,01 mm. Capillary tube can also be produced with combined limit deviations, i.e. either increased accuracy (outside diameter) or normal accuracy (tube wall thickness). Pipe curvature shall be within 3 mm in a 1 m section. The surface of the tubing shall be clean, smooth, without any signs of deformation, dents, stains, etc. If the diameter exceeds 1,6 mm, pipe ends shall be cut and machined. If the diameter is up to 1,6 mm the ends are not cut. Tubing must be cleaned with air jet at 0,49 MPa.

Properties

  • Tensile strength - up to 880 MPa
  • Relative elongation - up to 35%.
  • Density - 8,4 g/cm3

As agreed with purchaser, tubes of CrN78T should resist flattening, bending and be tested for leakproofness at pressure from 0.59 to 0.78 MPa. The disadvantages include the high cost of CrN78T tubes due to the presence of expensive nickel. But, durability, reliability, recyclability of the material - make it highly profitable.

E 10- 5 a 10 6 Heat capacity Density
Grad MPa 1/Grad W/(m-grad) g/cm3
20 2.24 12,6 8,4
200 2,13 13 16,7 8,3
400 2 13.8 20.6 8,26
600 1.84 14.7 24.8 8,18
800 15.5 28.9 8,09

Application

Due to its high resistance to corrosive influences, the pipe KhN78T is widely used in the manufacture of paint products, fertilizers and other materials containing "aggressive" components. Chromium increases the corrosion resistance of the alloy CrN78T, so the pipes are in demand in the construction industry for laying water pipes. The smooth surface of CrN78T pipes allows using them in pharmaceutics. Thanks to heat resistance, the pipe is quite often used in aircraft construction at working temperatures up to 1100 °C. Also, it serves for the manufacture of bodies of industrial thermometers and thermocouples.

Buy at best price

Evek GmbH has a wide range of CrN78T products in standard and non-standard parameters on stock. The prices are conditioned by technological features of production without including additional costs. The terms of realization of the orders are minimal. Wholesale customers receive discounts.