Steel 20kp
Designation
| Name |
The value |
| Designation GOST Cyrillic |
20кп |
| Designation GOST Latin |
20kp |
| Transliteration |
20kp |
| The chemical elements |
20 |
Description
Steel 20kp used: for the manufacture of sheet metal, 1−2 mm 4−14 category, intended for cold forming without heat treatment or after normalization, nipples, fittings, plugs, bolts, flanges, housings vessels and devices operating under low pressure and at temperatures from -20 °C to +425 °C, after carburizing and cyanidation parts, which require high surface hardness and low strength of the core (axles, fasteners, fingers, stars); electric-welded pipes.
Note
The degree of deoxidation — KP.
Standards
| Name |
Code |
Standards |
| Tapes |
В34 |
GOST 10234-77, GOST 19851-74 |
| Sectional and shaped rolling |
В32 |
GOST 1050-88, GOST 7417-75, GOST 8560-78, GOST 10702-78, GOST 14955-77, GOST 1050-2013, TU 14-1-2118-77, TU 14-11-245-88, TU 14-1-1271-75, TU 14-136-367-2008 |
| Sheets and stripes |
В33 |
GOST 1577-93, GOST 4041-71, TU 14-1-4516-88 |
| Classification, nomenclature and general norms |
В70 |
GOST 2771-81 |
| Pipes steel and connecting parts to them |
В62 |
GOST 3262-75, GOST 10704-91, GOST 10705-80, GOST 10707-80, TU 14-3-1428-86, TU 1373-022-05757850-08, TU 1373-013-02949352-2003 |
| Low-carbon steel wire |
В71 |
GOST 3282-74, GOST 5663-79 |
| Tapes |
В24 |
GOST 3560-73 |
| Steel wire medium- and high-carbon |
В72 |
GOST 3920-70, GOST 7372-79, GOST 9389-75, GOST 9850-72, GOST 17305-91, GOST 26366-84 |
| Sheets and stripes |
В23 |
GOST 82-70, GOST 14918-80, GOST 16523-97, GOST 19904-90, GOST 103-2006, GOST 19903-90 |
| Sectional and shaped rolling |
В22 |
GOST 8278-83, GOST 8281-80, GOST 8282-83, GOST 8283-93, GOST 8319.0-75, GOST 9234-74, GOST 10551-75, GOST 11474-76, GOST 19771-93, GOST 19772-93, GOST 2590-2006, GOST 2879-2006 |
| Bulls. Blanks. Slabs |
В31 |
OST 3-1686-90, TU 14-1-4944-90 |
Mechanical characteristics
| Section, mm |
sT|s0,2, MPa |
σB, MPa |
d5, % |
d4 |
d |
d10 |
y, % |
kJ/m2, кДж/м2 |
Brinell hardness number, MPa |
HRC |
HRB |
| Tape flatted average strength of 0.1-4.0 mm according to GOST 10234-77 in the state of delivery (indicated delivery) |
| - |
- |
490-830 |
- |
- |
- |
- |
- |
- |
- |
- |
- |
| - |
- |
390-540 |
- |
- |
- |
- |
- |
- |
- |
- |
- |
| - |
- |
540-690 |
- |
- |
- |
- |
- |
- |
- |
- |
- |
| - |
- |
690-830 |
- |
- |
- |
- |
- |
- |
- |
- |
- |
| - |
- |
≤540 |
- |
- |
≥15 |
- |
- |
- |
- |
- |
- |
| - |
- |
≤410 |
- |
- |
- |
- |
- |
- |
- |
- |
- |
| Rolled sheet 1-2 categories of heat-treated (annealing, normalization, high tempering or normalizing + tempering) in the delivery state according to GOST 4041-71 |
| 4-14 |
- |
340-490 |
≥28 |
- |
- |
≥24 |
- |
- |
≤127 |
- |
≤71 |
| Wire for cold heading as supplied by GOST 5663-79 |
| - |
- |
470-620 |
- |
- |
- |
- |
≥55 |
- |
- |
- |
- |
| - |
- |
≤640 |
- |
- |
- |
- |
≥50 |
- |
- |
- |
- |
| Longitudinal electric-welded pipes (Dy=10-530 mm) in the delivery condition. Listed marsvolta base metal |
| - |
≥225 |
≥372 |
≥22 |
- |
- |
- |
- |
- |
- |
- |
- |
| Hot-rolled steel and hot rolled with special surface finish |
| - |
- |
- |
- |
- |
- |
- |
- |
- |
≤156 |
- |
- |
| - |
- |
- |
- |
- |
- |
- |
- |
- |
≤132 |
- |
- |
| Steel calibrated and calibrated with special surface finish |
| - |
- |
≥490 |
≥7 |
- |
- |
- |
≥45 |
- |
≤197 |
- |
- |
| - |
- |
390-490 |
- |
- |
- |
- |
≥50 |
- |
≤163 |
- |
- |
| - |
- |
340-440 |
- |
- |
- |
- |
≥50 |
- |
≤163 |
- |
- |
| Leaves heat-treated 1 and 2nd categories |
| - |
- |
345-490 |
≥28 |
- |
- |
- |
- |
- |
≤157 |
- |
- |
| Hot-rolled sheet in the delivery condition. Group strength К330В |
| ≤2 |
- |
330-460 |
- |
≥23 |
- |
- |
- |
- |
- |
- |
≤73 |
| 2-3.9 |
- |
330-460 |
- |
≥24 |
- |
- |
- |
- |
- |
- |
≤73 |
| Cold-rolled sheet in the delivery condition. Group strength К330В |
| ≤2 |
- |
330-460 |
- |
≥24 |
- |
- |
- |
- |
- |
- |
≤73 |
| 2-3.9 |
- |
330-460 |
- |
≥25 |
- |
- |
- |
- |
- |
- |
≤73 |
| Strip. After normalizing or hot rolled |
| - |
- |
≥380 |
≥27 |
- |
- |
- |
≥55 |
- |
- |
- |
- |
| Cementation at 920-950 °C + quenching in water from 800-820 °C + vacation at 180-200 °C, air cooling |
| 50 |
≥295 |
≥490 |
≥16 |
- |
- |
- |
≥40 |
≥481 |
≥156 |
55-63 |
- |
Description mechanical marks
| Name |
Description |
| Section |
Section |
| sT|s0,2 |
Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2% |
| σB |
Limit short-term strength |
| d5 |
Elongation after rupture |
| d4 |
Elongation after rupture |
| d |
Elongation after rupture |
| d10 |
Elongation after rupture |
| y |
The relative narrowing |
| kJ/m2 |
Toughness |
| HRC |
Rockwell hardness (indenter diamond spheroconical) |
| HRB |
Rockwell hardness (indenter steel, spherical) |
Physical characteristics
| Temperature |
Е, ГПа |
r, кг/м3 |
l, Вт/(м · °С) |
R, НОм · м |
a, 10-6 1/°С |
С, Дж/(кг · °С) |
| 0 |
212 |
- |
- |
- |
- |
- |
| 20 |
212 |
- |
- |
- |
- |
- |
| 100 |
208 |
7834 |
51 |
219 |
123 |
486 |
| 300 |
197 |
7770 |
44 |
381 |
138 |
514 |
| 500 |
177 |
7599 |
39 |
601 |
148 |
555 |
| 600 |
163 |
7659 |
36 |
758 |
151 |
584 |
| 900 |
- |
7600 |
26 |
1135 |
152 |
703 |
A description of the physical symbols
| Name |
Description |
| Е |
The normal elasticity modulus |
| r |
Density |
| l |
Coefficient of thermal conductivity |
| R |
UD. the resistivity |
| a |
The coefficient of linear expansion |
| С |
Specific heat |
Technological properties
| Name |
The value |
| Weldability |
Welded without restriction (except XTO). Welding methods: SMAW, ADS submerged arc and gas protection, the CCC. |
| Propensity to temper brittleness |
Tend not. |
| Forging temperature |
Start - 1280 °C, the end - 750 °C. air Cooling. |
| Flock-sensitive sensitivity |
not sensitive. |
| Workability by cutting |
In the hot rolled condition with HB of 130 Kn TV.SPL.=1,7 Kn b.St.=1,6. |
