التسخين المسبق HPS690W — 1.2–1.6 kJ/mm، 10–13 mm: 150–300°F

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.

أين يُستخدم M270M HPS690W / M270 HPS100W

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.

M270M HPS690W / M270 HPS100W عند 10–13 mm (3/8–1/2 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.

التحكم في التسخين المسبق أدنى–أقصى لـ M270M HPS690W / M270 HPS100W

Highest-strength 690 MPa (100 ksi) bridge steel with restricted FC combinations. Table 12.8 specifies a preheat RANGE of 150–300°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.

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

جرّب تركيبات مختلفة

استخدم حاسبة التسخين المسبق D1.5 للجسور للبحث عن أي فولاذ AASHTO M270 ومستوى هيدروجين وتركيبة مدخل حراري. انظر أيضاً حاسبة التسخين المسبق D1.1 للفولاذ الإنشائي.

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