Tanım
Controlled-hardness Cr-Mo alloy steel
ASTM A193 B7M Threaded Rod
Heat-treated alloy steel all-thread for pressure bolting where the design requires B7M mechanical properties, hardness control and project-specific sour-service qualification.
Ürüne genel bakış
ASTM A193 Grade B7M threaded rod is a chromium-molybdenum alloy-steel bolting material with mechanical-property and maximum-hardness controls that differ from standard B7. It is frequently specified for sour hydrocarbon service and other applications where controlled hardness is part of the materials strategy.
B7M marking alone does not automatically establish compliance with every NACE MR0175 / ISO 15156 or project sour-service requirement. The purchase order must identify the environmental standard, heat-treatment sequence, hardness testing, supplementary tests and documentation required for the finished threaded rod.
ASTM A193 B7M threaded rod specifications
| Bolting standard | ASTM A193/A193M, ordered edition |
|---|---|
| Seviye / malzeme | Grade B7M, chromium-molybdenum alloy steel |
| Durum | Heat treated to B7M mechanical-property and hardness requirements |
| Konu sistemleri | ASME B1.1 ÇİL, UNF veya 8UN; metric threads when ordered |
| Boyut aralığı | 1/4–4 in and M6–M100 typical; exact range subject to testing and availability |
| Compatible nuts | ASTM A194 Grade 2HM commonly specified, subject to project requirements |
| Sour-service option | NACE MR0175 / ISO 15156 and purchaser supplements only when explicitly ordered |
| Finish options | Plain, black or qualified project coating; coating and lubricant reviewed together |
Son boyutlar, toleranslar, ısıl işlem, kaplama, test ve kabul kriterleri onaylanmış satın alma siparişine ve geçerli standart baskıya uygundur. Kullanılabilirlik çapa bağlıdır, uzunluk, iplik formu ve üretim miktarı.
Bu materyali neden belirtmeniz gerekiyor??
B7M is considered when the materials engineer needs an established Cr-Mo bolting grade with controlled hardness. It is not simply a lower-cost alternative to corrosion-resistant alloy bolting; çevre, stress, cathodic protection and service temperature still govern selection.
Mühendislik notu
Kesme, thread production and heat treatment must follow the ordered standard and project sequence. Confirm whether hardness testing is required on each piece, each end or by lot, and whether testing must occur after all manufacturing operations.
Tipik uygulamalar
Kalite, muayene ve dokümantasyon
Procurement should define hardness frequency, mekanik test, heat-treatment traceability and any sour-service supplements. A complete B7M package commonly includes MTC, hardness results, thread inspection and coating records.
- EN 10204 3.1 malzeme test sertifikası
- Isı numarası ve parti izlenebilirliği
- Kimyasal bileşim ve mekanik özellikler
- Boyutsal inceleme ve iplik ölçümü
- Sipariş edildiğinde paslanmaz ve nikel alaşımları için PMI
- Uygulanabilir olduğunda kaplama kalınlığı veya yüzey incelemesi
- Anlaşmaya göre üçüncü taraf denetimi ve ek testler
- İhracat işaretlemesi ve denize uygun ambalaj
Teklif için gerekli bilgiler
- Malzeme kalitesi, geçerli malzeme/cıvata standardı ve gerekli sürüm
- Çap, iplik serisi, adım ve diş sınıfı veya toleransı
- Toplam uzunluk, kesme sonu gereksinimleri ve miktarı
- Isıl işlem, yüzey bitirme veya kaplama sistemi
- Eşleşen somunlar ve pullar, safra oluşumunu önleyici gereksinimler dahil
- Denetim planı, MTC, PMI, NDE ve üçüncü taraf tanık gereklilikleri
- Teslimat hedefi, paketleme ve gerekli program
Sık sorulan sorular
öyle mi ASTM A193 B7M automatically NACE compliant?
HAYIR. B7M provides grade-specific hardness and mechanical requirements, but NACE MR0175 / ISO 15156 suitability depends on the exact environment, ürün formu, heat treatment and project requirements.
What nut grade is commonly used with B7M?
ASTM A194 Grade 2HM nuts are commonly specified. The engineer must confirm nut grade, sertlik, coating and thread compatibility.
How does B7M differ from B7?
B7M has lower strength and controlled maximum hardness requirements compared with B7, together with grade-specific manufacturing and testing provisions.
Can B7M threaded rod be fluoropolymer coated?
Yes when permitted by the design and qualified purchase specification. Coating thickness, cure temperature, thread fit, lubricant and installation torque require coordinated control.
İlgili dişli çubuk ürünleri
Teknik teklif isteyin
Malzeme listenizi gönderin, çizim veya proje özellikleri. SASA FLANGE notu gözden geçirecek, iplik, boyutlar, Teklif öncesi dokümantasyon ve teslimat gereksinimleri.
