Steel 07Х20Н25М3Д2ТЛ

Designation

Name The value
Designation GOST Cyrillic 07Х20Н25М3Д2ТЛ
Designation GOST Latin 07X20H25M3D2TL
Transliteration 07H20N25M3D2TL
By chemical elements 07Cr20Н25Mo3Cu2Ti

Description

07Х20Н25М3Д2ТЛ steel is used: for the manufacture of the 1st, 2nd and 3rd groups casting parts of valves and actuators to it operating in sulphuric and phosphoric acids of various concentrations at temperatures up to +80 °C, and in less aggressive environments when the working environment temperature from -70 to +300 °C without limitation of the rated working pressure.

Note

Casting parts of pipe fittings of steel 07Х20Н25М3Д2ТЛ demanding resistance to corrosion cracking are subjected to stabilization annealing step (Mode 2).

Standards

Name Code Standards
Steel castings В82 OST 26-07-402-83, ST ЦКБА 014-2004
Welding and cutting metals. Soldering, riveting В05 RD РТМ 26-07-233-79

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu Ti Mo
ST ЦКБА 014-2004 ≤0.07 ≤0.02 ≤0.03 ≤0.8 19-21 ≤0.8 24-26 Rest 1.8-2.2 0.4-0.7 2.3-3
Fe is the basis.

Mechanical properties

sT|s0,2, MPa σU, MPa d y, % KCU, kJ/m2
Casting parts of pipe fittings. Mode 1: Quenching in water from 1100-1150 °C or Mode 2: Annealing at 1100-1120 °C (exposure 1.5 h), cooling with the furnace to 950 °C (exposure 2 hours), cooled with the furnace to 300 °C, air cooling
≥200 ≥400 ≥20 ≥20 ≥800

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d Elongation after rupture
y The relative narrowing
KCU Toughness

Technological properties

Name The value
Surfacing For the argon arc and TIG welding of sealing and friction surfaces of parts of pipeline fittings are used electrodes and welding rods of alloy 06Х20Н10М3Д3С4Л po RD RTM 26-07-233-79. Before welding the parts must be subjected to preliminary heating in a furnace at a temperature of from +400 to +650 °C. To enhance the corrosion resistance of weld metal and relieve internal stresses after welding should be heat treatment of parts in the following mode: fit into the oven at temperatures up to +500 °C, heating from +950 to +1050 °C, exposure - 1.5 to 2 hours, cooling with the furnace.