M270M HPS690W पूर्वतापन — 2.0–2.8 kJ/mm, 25–50 mm: 250–400°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.

M270M HPS690W / M270 HPS100W कहाँ उपयोग होता है

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.

25–50 mm (1–2 in) पर M270M HPS690W / M270 HPS100W

HPS690W (HPS100W) at 40–65 mm is the thickest plate commonly used with this grade. Many thickness-heat input combinations at this tier are prohibited in Table 12.8 — the fabricator must verify that the planned welding procedure matches a permitted cell before beginning production. The permitted preheat ranges narrow further, often spanning only 50°F between minimum and maximum, making continuous temperature monitoring essential.

M270M HPS690W / M270 HPS100W के लिए न्यून-अधि पूर्वतापन नियंत्रण

Highest-strength 690 MPa (100 ksi) bridge steel with restricted FC combinations. Table 12.8 specifies a preheat RANGE of 250–400°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.

2.0–2.8 kJ/mm पर M270M HPS690W / M270 HPS100W

विभिन्न संयोजन आज़माएँ

किसी भी AASHTO M270 स्टील, हाइड्रोजन स्तर, और ऊष्मा इनपुट संयोजन को देखने के लिए D1.5 ब्रिज पूर्वतापन कैलकुलेटर का उपयोग करें। स्ट्रक्चरल स्टील के लिए D1.1 पूर्वतापन कैलकुलेटर भी देखें।

संबंधित गाइड