説明
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.
製品概要
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, 硬さ試験, supplementary tests and documentation required for the finished threaded rod.
ASTM A193 B7M threaded rod specifications
| Bolting standard | ASTM A193/A193M, ordered edition |
|---|---|
| 学年 / 材料 | Grade B7M, chromium-molybdenum alloy steel |
| Condition | Heat treated to B7M mechanical-property and hardness requirements |
| スレッドシステム | ASME B1.1 UNC, UNFまたは8UN; metric threads when ordered |
| サイズ範囲 | 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 |
| 仕上げオプション | 無地, black or qualified project coating; coating and lubricant reviewed together |
最終寸法, 公差, 熱処理, コーティング, テストおよび合格基準は、確認された発注書および該当する標準エディションに従います。. 入手可能かどうかは直径によって異なります, 長さ, ねじ形状と生産数量.
この材質を指定する理由?
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; environment, ストレス, cathodic protection and service temperature still govern selection.
エンジニアリングノート
切断, 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.
代表的な用途
品質, 検査と文書化
Procurement should define hardness frequency, 機械的試験, 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 材料試験証明書
- 熱価とバッチのトレーサビリティ
- 化学組成と機械的性質
- 寸法検査とねじゲージ
- 注文時のステンレスおよびニッケル合金の PMI
- 該当する場合、コーティングの厚さまたは表面検査
- 第三者による検査および契約による追加検査
- 輸出マーキングと耐航性のある梱包
お見積りに必要な情報
- 材質グレード, 準拠材質/ボルト規格と必要なエディション
- 直径, スレッドシリーズ, ピッチとねじの等級または公差
- 全長, カットエンドの要件と数量
- 熱処理, 表面仕上げまたはコーティングシステム
- 適合するナットとワッシャー, かじり防止要件を含む
- 検査計画, MTC, PMI, 臨死体験および第三者証人の要件
- 配送先, 梱包と必要なスケジュール
よくある質問
は ASTM A193 B7M automatically NACE compliant?
いいえ. B7M provides grade-specific hardness and mechanical requirements, しかし NACE MR0175 / ISO 15156 suitability depends on the exact environment, 製品形態, 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, 硬度, 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.
ねじ棒関連商品
技術的な見積もりをリクエストする
部品表を送信してください, 図面またはプロジェクト仕様書. SASA FLANGE 成績を見直します, 糸, 寸法, 見積前の書類と納品要件.
