Asosiy farq shundaki, ASTM A709 Grade 36 AQSH standarti boʻlib, minimal oqish quvvati 36000 psi (36 ksi), Q345q esa 345 MPa minimal oqish quvvatiga ega Xitoy standartidir. Ikkalasi ham koʻpriklar uchun ishlatiladigan yuqori-past qotishma poʻlatlardir, lekin ular turli standart spetsifikatsiyalari va mustahkamlik darajalariga ega, Q345q bir xil birliklarga aylantirilganda yuqori minimal oqish kuchiga ega.
Kimyoviy tarkibi % Mahsulot tahliliA709 36-sinf
|
Qalinligi mm |
Strukturaviy po'lat |
Chelik plastinka |
Dumaloq po'lat |
|||||
|
20 dan kam yoki teng |
20- 40 dan kam yoki teng |
40 - 65 dan kichik yoki teng |
65- 100 dan kam yoki teng |
20 dan kam yoki teng |
20- 40 dan kam yoki teng |
40- 100 dan kam yoki teng |
||
|
C,maks,% |
0.25 |
0.25 |
0.25 |
0.25 |
0.27 |
0.26 |
0.27 |
0.28 |
|
Mn,% |
… |
… |
0.80-1.20 |
0.80-1.20 |
0.80-1.20 |
… |
0.60-0.90 |
0.60-0.90 |
|
P,maks,% |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
|
S,maks,% |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
|
Si |
0,40 maks |
0,40 maks |
0,40 maks |
0.15-0.40 |
0.15-0.40 |
0,40 maks |
0,40 maks |
0,40 maks |
|
Cu, min,% |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
Sinfning mexanik xususiyatlariA709 36-sinf
|
Baho |
Qalin |
Yo'l bering Min |
Kuchlanish [MPa] |
Cho'zilish min % |
kamaytirish Min % |
HB |
|||
|
Chelik plastinka |
Strukturaviy po'lat |
||||||||
|
200 mm |
50 mm |
200 mm |
50 mm |
||||||
|
A709 36[250] |
100 dan kam yoki teng |
250 |
400-550 |
20 |
23 |
20 |
21 |
|
|
|
|
250 |
400 min |
|
|
20 |
19 |
|
||
Q345R po'lat plitalar kimyoviy tarkibi:
| Chelik darajasi | C % | Si % | Mn % | Cu % | Ni % | Cr% | Oy % | V % | Ti % | Alt % | P % | S % | Nb |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Q345R | 0.20 | 0.55 | 1.2-1.7 | 0.30 | 0.30 | 0.30 | 0.08 | 0.050 | 0.030 | 0.020 | 0.025 | 0.010 | 0.050 |
Q345R po'lat plitalar mexanik xususiyati:
| Chelik darajasi | Qalinligi (mm) | Minimal rentabellik | Kuchlanish | Cho'zilish | Minimal ta'sir energiyasi | |
|---|---|---|---|---|---|---|
| Daraja | Min J | |||||
| Q345R | 3-16 | 345Mpa | 510-640 Mpa | 21% | 0 | 41J |
| 16-36 | 325Mpa | 500-630 Mpa | 21% | 0 | 41J | |
| 36-60 | 315 Mpa | 490-620 Mpa | 21% | 0 | 41J | |
| 60-100 | 305 Mpa | 490-620 Mpa | 20% | 0 | 41J | |
| 100-150 | 285 Mpa | 480-610 Mpa | 20% | 0 | 41J | |
| 150-250 | 265 Mpa | 470-600 Mpa | 20% | 0 | 41J | |
