638B Steel Plate Applications & Ordering Guide

638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate 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 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate with EN 10204 mill test certificates.

This page is a standalone technical article. For the primary overview on the original URL, see 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate primary specification page.

Typical Applications and Service Conditions

638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate 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 Hot rolled or tempered; delivery hardness 275-335 HB should be stated explicitly on the purchase order.

Industry Use Cases

Pressure equipment and process: shells, heads, and related platework when drawings name 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate. 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 (638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate)

Heat / melting analysis per WYJ042-2005. Mo upper limit raised to 0.50 by WYJ004-2006 amendment. Thickness up to 400 mm for plastic-mould parts. Confirm edition and Mo band on the MTC.

Element	Min %	Max % / requirement
C	0.34	0.42
Si	0.30	0.60
Mn	1.00	1.50
P	-	<=0.030
S	-	<=0.020
Cr	1.80	2.40
Mo	0.20	0.50
Ni	0.15	0.25

Mechanical Properties - Supporting Data (638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate)

Hardness is the primary acceptance property on the mill sheet. Tensile allowables for mould design come from the purchaser drawing / tool-steel practice, not from this overview alone.

Property	Requirement
Delivery hardness	275-335 HB
Delivery condition	Hot rolled or tempered
Product thickness scope (WYJ042)	<=400 mm
Flatness	<=7 mm/m
Thickness tolerance (WYJ042)	-0 / +3 mm

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
Enterprise	WYJ042-2005 638B	Primary mill tech condition
Amendment	WYJ004-2006	Mo adjusted to 0.20-0.50
Size / shape	GB/T 709	Dimensional defaults referenced by mill sheet
Family	Plastic-mould / die alloy plate	Not a drop-in for P20 / 1.2738 without engineer review
Related	Cr-Mo-Ni mould steels	Compare Cr/Mo/Ni bands and hardness window before substitution

Frequently Asked Questions

Where is 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate typically applied?

638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate 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. Primary overview: 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate.

What service conditions drive selection of 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate?

Design temperature and pressure, toughness or creep allowables, weldability, corrosion or process media, and the governing code edition drive selection. Delivery condition Hot rolled or tempered; delivery hardness 275-335 HB must align with the ordered specification.

Can a near-equivalent replace 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate 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 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate.

What fabrication notes matter for 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate?

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 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate.

How should I RFQ 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate plate from Gangsteel for a project?

Send 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate, 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 638B (WYJ042-2005 / WYJ004-2006) plastic-mould alloy die steel plate, 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.