كيفية قراءة علامات شفة ASTM A182

Technical guideReviewed: 30 يوليو 2026Prepared by SASA FLANGE Technical Content Team

إجابة مباشرة

An alloy steel flange marking typically identifies the manufacturer, مواصفات المواد والصف, الحجم الاسمي, pressure class and traceability information required by the applicable standards and purchase order. RTJ products may also carry ring-groove identification. Always compare the marking with the certificate and purchase description.

Key takeaways

Marking identifies the item; it does not replace certification or inspection.
Heat-number traceability should remain legible after coating, machining and shipment.
Do not infer missing grade or class from colour code alone.

The identification chain

The strongest traceability chain connects the physical marking to the packing list, inspection report, heat-treatment batch and original material certificate. If any link uses a different heat number, grade or quantity, resolve the discrepancy before installation.

Transferred markings after cutting or machining should follow a controlled procedure authorized by the quality system.

Common marking elements

عنصر	What it tells the buyer
Manufacturer name/trademark	Responsible product source
ASTM grade	تسمية المواد, such as A182 F22 or F91
NPS والفئة	Nominal size and rating designation
Heat/trace number	Link to material and production records
RTJ groove identification	Required metallic ring geometry where applicable
Additional project marks	PO item, inspector stamp or supplementary requirement

Marking methods and placement

Low-stress stamping, dot-peen, engraving or other approved methods may be used depending on material and project rules. Marking should remain legible without damaging pressure-boundary or sealing surfaces.

Coating and preservation teams should mask or reproduce identification under a documented system. Tags can supplement—but should not casually replace—durable product marking.

What to do when marking and MTC disagree

Quarantine the flange. Compare purchase order, packing list, supplier certificate and inspection records. Ask the manufacturer for a controlled correction or documented re-verification; do not grind and restamp the item based on assumption.

PMI may help confirm alloy family, but it cannot by itself reconstruct the original heat traceability or approve unauthorized re-marking.

الأسئلة المتداولة

Does “600” stamped on a flange mean 600 رطل لكل بوصة مربعة?

لا. It normally identifies Class 600. Allowable pressure depends on material and temperature.

Is colour coding an ASTM flange marking?

Colour coding may be a supplier or project segregation aid. Durable markings and traceable documents remain the primary identification.

Can a flange be released if the heat number is unreadable?

Only through an approved traceability recovery and re-identification process supported by objective records and any required verification.

Primary standards referenced

Always verify the edition specified by the purchase order and obtain the complete controlled standard for design and acceptance.

Request an alloy steel flange quotation

Send the material grade, معيار, مصادر القدرة النووية, فئة الضغط, نوع شفة, تواجه, pipe schedule, متطلبات الكمية والتفتيش. SASA FLANGE will review the technical description before quotation.

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