718H Steel Plate Applications & Ordering Guide

718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel) is specified for industrial fabrications where the drawing or material list names this grade. This applications page explains where the grade is used, what service conditions drive selection, and which certificate details belong on the purchase order. Gangsteel supplies 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel) with EN 10204 mill test certificates.

Typical Applications and Service Conditions

718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel) plate is ordered for pressure equipment, process vessels, heat-exchanger related fabrications, structural members under the governing code, and project packages that call the grade by name. Match the mill test certificate grade mark to the calculation sheet; do not treat near-equivalents as automatic substitutes.

Service drivers include the design temperature and pressure of the governing code (ASME, EN/PED, class society, or project specification), weld procedure qualification needs, toughness or creep allowables where applicable, and inspection scope. Delivery condition Pre-hardened typically 32-36 HRC (HH variants higher); no secondary QT required for many moulds should be stated explicitly on the purchase order.

Industry Use Cases

Pressure equipment and process: shells, heads, and related platework when drawings name 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel). Power and energy: boiler and heat-recovery fabrications under the ordered edition. Marine / offshore (when classed): only when the society material list names this exact grade stamp. Always keep heat-number traceability on cut pieces.

Chemical Composition - Supporting Data (718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel))

Heat analysis for 3Cr2NiMo / 1.2738 / 718H family. Some mill datasheets tighten Si/Mn/Cr bands - confirm ordered edition.

Element / rule	Requirement
C	0.32-0.42
Si	0.20-0.80
Mn	1.00-1.50
Cr	1.40-2.00
Ni	0.80-1.20
Mo	0.30-0.55
P, max	0.030
S, max	0.030

Mechanical Properties - Supporting Data (718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel))

Confirm thickness, specimen orientation, and any supplementary impact, UT, or hardness requirements on the PO.

Property	Requirement
Delivery hardness (typical pre-hard)	32-36 HRC (~300 HB)
Tensile Rm (example QT 860 C / temper 650 C)	~1000-1235 MPa (condition-dependent)
Yield Rp0.2 (example prehard ~300 HB)	~826 MPa
Elongation (example prehard)	~17%
Delivery	Pre-hardened mould plate; nitriding optional

Related / Near-Equivalent Grades

Near-equivalents are for cross-reference only. They are not automatic code substitutes. Substitution requires engineer approval and matching certificate scope.

System	Grade	Note
DIN	1.2738	European designation
AISI	P20+Ni	Ni-modified P20
GB	3Cr2NiMo	Chinese designation

Frequently Asked Questions

Where is 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel) typically applied?

718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel) is applied where design documents, class material lists, or purchaser specs name this grade for pressure, process, structural, or marine fabrications as applicable. Match the MTC marking to the drawing.

What service conditions drive selection of 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel)?

Design temperature and pressure, toughness or creep allowables, weldability, corrosion or process media, and the governing code edition drive selection. Delivery condition Pre-hardened typically 32-36 HRC (HH variants higher); no secondary QT required for many moulds must align with the ordered specification.

Can a near-equivalent replace 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel) on an applications drawing?

Not without redesign and written approval. Near-equivalents differ in chemistry, heat treatment, impact temperature, or product form. Commercial swaps create non-conformance when the dossier names 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel).

What fabrication notes matter for 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel)?

Use approved WPS/PQR packages for the thickness and filler, control heat input, and preserve heat-number traceability on cut pieces. State any supplementary UT, PMI, or impact tests on the purchase order.

What certificate and marking should an applications PO demand?

EN 10204 3.1 is standard; 3.2 when a purchaser-appointed inspector witnesses tests. The MTC should show heat analysis, tensile results, delivery condition, and heat number aligned with 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel).

How should I RFQ 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel) plate from Gangsteel for a project?

Send 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel), thickness x width x length (or nesting list), quantity, delivery condition, optional NDT/PMI, certificate type, destination, and any dual-mark needs. Note the end use when special flatness or cut-to-size packaging is required.

Ordering and Mill Certificates

State grade 718H / 3Cr2NiMo (P20+Ni; DIN 1.2738 pre-hardened plastic mould steel), dimensions, quantity, delivery condition, optional NDT/PMI, and certificate (EN 10204 3.1 standard; 3.2 when third-party inspection is ordered). Gangsteel supplies export plate and related products with mill test certificates. Contact Gangsteel for stock and mill production RFQs.