AASHTO/AWS D1.5:2025 · Tabel 12.8 · Fraktur Kritis

Preheat M270M HPS690W — 1.2–1.6 kJ/mm, 6–10 mm: 100–150°F

Persyaratan preheat fraktur kritis untuk M270M HPS690W / M270 HPS100W pada ketebalan 6–10 mm (1/4–3/8 in), sesuai AASHTO/AWS D1.5:2025, Kode Pengelasan Jembatan.

Berdasarkan AWS D1.5:2025 — setiap nilai dilacak ke pasal.

Rentang Preheat Fraktur Kritis

100–150°F / 40–60°C

Tabel 12.8 — masukan panas 1.2–1.6 kJ/mm pada ketebalan 6–10 mm (1/4–3/8 in)

AASHTO/AWS D1.5M/D1.5:2025 Tabel 12.8

Baik suhu preheat/interpass minimum MAUPUN maksimum harus dijaga. Melebihi 150°F berisiko merusak mikrostruktur Q&T.

Alat referensi. Verifikasi terhadap edisi yang berlaku dan WPS yang disetujui Insinyur.

AASHTO M270 High-Performance Grades

M270M HPS690W / M270 HPS100W

AASHTO M270M HPS690W (M270 HPS100W) is the highest-strength bridge steel at 690 MPa (100 ksi) yield, reserved for the most demanding long-span and cable-stayed bridge applications. It follows a completely different FC preheat table (Table 12.8) with min-max ranges and many prohibited thickness-heat input combinations marked with “—”. Table 12.8 requires H4 or H8 designated consumables; H16 is not permitted. NFC preheat per Table 6.3 Group 2; maximum interpass per Table 6.4 is 205°C (400°F) for material up to 40 mm, 230°C (450°F) above.

Aplikasi Jembatan

Di Mana M270M HPS690W / M270 HPS100W Digunakan

Reserved for the most demanding long-span and cable-stayed bridge applications where maximum weight reduction justifies the material cost premium and fabrication complexity. Table 12.8 imposes both minimum AND maximum preheat limits, and many thickness-heat input combinations are outright prohibited. Fabricators must plan weld procedures around the permitted combinations before cutting plate. Filler metals must carry the H4 or H8 supplemental designator — H16 is not permitted for HPS690W FC applications.

Detail Fabrikasi

M270M HPS690W / M270 HPS100W pada 6–10 mm (1/4–3/8 in)

HPS690W (HPS100W) at up to 20 mm is used in deck plate and stiffener components on orthotropic steel deck bridges — specialized long-span applications where the 100 ksi yield enables very thin plate to carry traffic loads. Table 12.8 requires both min and max preheat even at this thin section, and several heat input combinations are prohibited. Only H4 or H8 consumables are permitted; H16 is not allowed at any thickness.

Rentang Preheat Diperlukan

Kontrol Preheat Min–Maks untuk M270M HPS690W / M270 HPS100W

Highest-strength 690 MPa (100 ksi) bridge steel with restricted FC combinations. Table 12.8 specifies a preheat RANGE of 100–150°F for this thickness and heat input combination. Unlike other FC grades, HPS690W requires both minimum AND maximum preheat control because the Q&T microstructure is sensitive to both excessive and insufficient heat. Many thickness-heat input combinations are prohibited ("—" in the table) because no safe preheat window exists — the steel cannot be reliably welded under those conditions.

Ketebalan Lainnya

M270M HPS690W / M270 HPS100W pada 1.2–1.6 kJ/mm

Kalkulator Interaktif

Coba Kombinasi Berbeda

Gunakan Kalkulator Preheat Jembatan D1.5 untuk mencari baja AASHTO M270, tingkat hidrogen, dan kombinasi masukan panas. Lihat juga Kalkulator Preheat D1.1 untuk baja struktural.

Pelajari Lebih Lanjut

Panduan Terkait

Pertanyaan Umum

Berapa rentang preheat untuk HPS690W pada 6–10 mm (1/4–3/8 in) dengan 1.2–1.6 kJ/mm?

D1.5 Tabel 12.8 memerlukan rentang preheat 100–150°F (40–60°C) untuk HPS690W pada 6–10 mm (1/4–3/8 in) dengan masukan panas 1.2–1.6 kJ/mm. Baik minimum MAUPUN maksimum harus dikontrol.

Mengapa HPS690W memiliki batas preheat maksimum?

HPS690W mencapai kekuatannya 690 MPa (100 ksi) melalui quenching dan tempering. Preheat berlebih dapat melunakkan mikrostruktur yang di-temper di zona terpengaruh panas. Batas maksimum 150°F (60°C) melindungi kondisi Q&T ini.

Data referensi D1.5:2025. Tidak berafiliasi dengan AWS atau AASHTO.