Heavy steel plate rolling and how the route maps to flatness stability

Heavy plate rolling is primarily judged by repeatable control of thickness, shape, and flatness, typically through:

• Reheating and descaling for surface control
• Rolling for thickness, profile, and shape control
• Controlled cooling when property windows require it
• Hot levelling to stabilize flatness on wide and heavy sections
• Plate-by-plate identification for traceability and release

When the goal is fewer seams, lower NDT scale, and more stable assembly outcomes, plate format and shape stability become practical risk controls.

4100mm Heavy and Wide Plate for seam reduction in heavy fabrication

In large panel builds and shell-course fabrication, plate width is not a cosmetic choice. It directly drives how many longitudinal joints enter the weld map, how many UT/RT intersections appear in the ITP, and how much fit-up time sits in front of each welding cycle. For procurement, this becomes a predictable trade: a wider plate can remove an entire seam line, which usually means fewer weld meters, fewer NDT callouts, fewer repair loops, and a cleaner distortion-control plan on large assemblies.

This is where a wide-format starting material helps, especially when the package includes large deck panels, module base frames, box structures, or rolled shells that would otherwise be split into multiple strips. Using a wider plate often allows a simpler cutting plan, fewer part numbers, and fewer plate-to-plate transitions that can slow receiving and traceability closure. It also reduces the chance that one late plate holds a panel from being assembled and released.

A practical example is 4100mm Heavy and Wide Plate, used when the design benefits from larger-format plates and heavy thickness in the same supply window. Buyers typically evaluate this option against a short checklist: whether single-piece weight remains within site lifting capacity, whether transport envelope and packaging can protect edges and surfaces, and whether flatness and camber are controlled tightly enough to avoid corrective work after cutting. When those items are aligned, wider plate format is a straightforward way to reduce fabrication uncertainty without changing the design intent.

Heavy steel plate fabrication and what usually closes approvals

Heavy plate fabrication releases smoothly when the package closes:

• MTC (3.1 or 3.2 as specified) with heat and plate ID traceability
• Dimensional and shape records for thickness, width, length, and defined flatness criteria
• UT or other NDT reports aligned to PO and ITP scope and acceptance class
• Surface and edge condition aligned to cutting and coating interfaces
• Packing and identification discipline that preserves plate-to-heat mapping

In heavy fabrication, traceability and inspection alignment can be as release-critical as grade naming.

Steel plate as starting material and what it becomes

• Pressure equipment and process vessels: shell courses, cylinders, dished heads, exchanger shells, tower sections
• Large welded structures: offshore module base frames, deck panels, skids, gusset plates and load-bearing plates
• Cylindrical products: plate-formed welded pipe (e.g., LSAW), rolled shells and structural cylinders, tower sections
• Wear and high-strength components: liners, heavy equipment structural parts, lifting and transport structures

With different delivery conditions and toughness/shape controls, the same nominal plate can behave very differently in rolling/bending, weld HAZ sensitivity, UT outcomes, and dimensional stability after fabrication.

Steel plate size and why format drives seams and NDT

Steel plate size is defined by thickness × width × length, then completed by tolerances, shape limits, and delivery condition. For large panels, shell courses, and heavy welded assemblies, width directly affects:

• Longitudinal seam count and total weld length
• The number of NDT joints (UT/RT workload and rework exposure)
• Fit-up rhythm and distortion control on large assemblies

For schedule-driven packages, plate format becomes a practical lever to reduce downstream variability.

Steel plate thickness: thickness changes the manufacturing route

Steel plate thickness influences:

• Forming feasibility and minimum rolling radius, spring-back control
• Weld preparation, pass count, heat input window, and distortion management
• NDT practicality and inspection planning on heavy welds
• Heat treatment logic on thick-welded parts when required by the code or project

Heavy plate programs usually prioritize thickness consistency and stable flatness after cutting and welding.

Steel plate weight and a practical calculation

A common estimate uses density near 7.85 t/m³ for carbon and low-alloy steels:
Steel plate weight (kg) = Length (m) × Width (m) × Thickness (mm) × 7.85
Example: 6.0 m × 2.0 m × 20 mm
Weight ≈ 6.0 × 2.0 × 20 × 7.85 = 1884 kg
Weight is used for lifting plans, transport limits, and receiving checks, while final shipping weight is closed by packing lists and measured weights.

Steel Plate Rolling Machine Fabrication Meaning 3-Roll and 4-Roll Bending Rolls

For fabrication, “steel plate rolling machine” usually means bending rolls (3-roll / 4-roll). The plate thickness is not reduced; the machine creates controlled plastic bending to achieve a target radius and seam fit-up.

3-roll plate rolling machine (pyramid / initial-pinch)
A 3-roll machine forms curvature with a three-point bending triangle. The plate is driven by the bottom rolls (or one bottom roll), while the top roll applies bending force and is offset to set the radius. Radius is achieved by progressive passes until the shell reaches target diameter.
Functional control points: radius setting by top-roll offset, spring-back compensation by over-bend + re-roll passes, cone rolling by differential side adjustment/skew. Limitation: edge pre-bend typically needs repositioning and/or flipping, so flat-end length control is weaker and seam fit-up is more operator-dependent.

4-roll plate rolling machine (double-pinch)
A 4-roll machine positively pinches the plate between the top and bottom rolls, while two side rolls move independently to generate bending moment and control radius. The positive grip enables controlled feeding and direct pre-bending of both leading and trailing edges with minimal flipping.
Functional control points: tighter and more repeatable roundness, better flat-end minimization, more stable seam gap control, and more controlled cone rolling via asymmetric side-roll positioning. It is generally more consistent on thicker plates and higher-strength materials because slip is reduced and geometry is held under pinch.

What “control” means in practice
Roundness and fit-up are governed by roll positioning + force control (often hydraulic with encoder/CNC feedback) and by planned over-bend to offset spring-back. For long/thick shells, accuracy is limited by roll deflection, so machines rely on roll crowning/compensation and controlled pass schedules to avoid barrel/hourglass shapes.

Plate category and delivery condition and why it changes weld-ability and forming behavior

Typical delivery conditions and their practical impact:

• As-rolled for general structural needs when toughness windows are not tightly constrained
• Normalized for more uniform structure and stable properties where consistency matters
• TMCP for optimized strength–toughness balance and weld-ability in demanding structural or offshore use
• Quenched and tempered (Q&T) for defined high-strength and toughness windows, with stricter discipline on welding heat input

These choices move the risk focus from nominal strength to fabrication drivers such as HAZ control, UT behavior, spring-back, and low-temperature toughness windows.

Starting Material vs Raw Material in Steel Plate Supply Chains

Operational definitions

Starting material is the controlled, released input to a defined manufacturing step. It sets the auditable start point of a manufacturing route, so traceability, inspection scope, release status, and certification closure run from one fixed boundary.
Raw material is upstream steel-making input such as ore, scrap, alloying elements, deoxidizers, and other consumables. It is managed through metallurgical process control and is typically not treated as a piece-level deliverable chain in a project data package.
The practical difference is boundary control
Starting material defines where the delivery chain begins
Raw material defines how upstream variability is controlled to achieve required chemistry and performance

Why the distinction matters in delivery

Starting material defines where the delivery chain begins and where responsibility becomes auditable. Raw material explains how the mill achieves chemistry and performance but does not normally extend to item-by-item project traceability.

Starting material control criteria and release status

A starting material definition is executable only when it meets three mandatory conditions.

Controlled status
Controlled status means the input is verified and formally released before it is allowed to enter the next step. In practice, release is typically based on six verification blocks: (1) identification and traceability match (heat/plate/lot and mapping integrity), (2) certificate and document validity (MTC completeness, standard/grade/condition, sampling unit alignment), (3) visual and dimensional acceptance (thickness/width/length tolerances, surface condition, edge condition, plate flatness), (4) material condition confirmation (delivery condition and heat treatment status where applicable, hardness/impact requirements when specified), (5) additional testing triggers and results when required (e.g., PMI/UT/retests driven by contract or discrepancies), and (6) controlled release and segregation (released vs hold/quarantine with documented disposition).
Process entry point
The item is explicitly listed as the input to a specific manufacturing step on the route card, manufacturing plan, or traveler.
Traceable identification
The item is identified at least to heat/lot level and remains retrievable through mapping when converted into downstream pieces.
Raw material is defined differently and should be stated differently.
Upstream input
Fed into steel-making and refining operations rather than project-defined fabrication steps.
Process-driven impact
Controlled through charge mix, refining, degassing, and casting parameters to achieve target chemistry, cleanliness, and internal soundness.
Not a piece-level deliverable chain
Normally not expanded into item-by-item traceability evidence in the customer-facing data book, unless a specific regulatory or contractual requirement requires it.

Manufacturing route levels and starting material selection

Starting material changes with the route level being discussed. This is expected because the certified route changes.

Plate mill route
Starting material is commonly the slab. The slab is the controlled input into reheating and rolling, tied to heat identity and governed by defined sampling and test rules.
Downstream fabrication route
Starting material is commonly the released steel plate. The fabricator’s controlled route begins at receiving inspection, certificate verification, marking control, ID inheritance after cutting/forming, and subsequent NDE and dimensional checks.
Route boundary statement rule
Name the route first, then define the starting material for that route. Mixing route start points in one statement creates avoidable audit ambiguity.

Traceability boundary and ID inheritance control

Once starting material is defined, the traceability boundary is fixed. From that boundary onward, traceability must be continuous and evidenced.
Deliverable traceability evidence pack commonly includes four proof sets：

Unique ID rules
Heat No., Plate No., Lot No., Piece ID defined with non-duplicating formats and controlled assignment rules.
ID inheritance control
After cutting, segmentation, beveling, or forming, each child piece inherits traceability through stamping, tags, labels, or controlled paint marking with documented rules.
Trace mapping that can be audited
Any piece ID can be traced back to parent plate and heat, and linked to the specific test records through a controlled mapping table or equivalent record.
Physical-to-document consistency
Physical marking, packing list, inspection reports, and MTC references reconcile without gaps.

Raw-material traceability typically exists as internal mill records
Charge mix sheets, alloy batch tracking, ladle/product analyses, refining and casting logs, and process control records support capability and investigation, but they are not usually the backbone of a project’s piece-level delivery chain.

Certificate closure and inspection scope

Plate supply level typically closes via heat-indexed MTC/CMTR covering chemistry, mechanicals, standard, and sampling rules, plus NDT/HT records if required.
Fabrication level closes from released plate through receiving inspection, ID transfer, NDE/dimensional reports, and final release—bound to piece IDs.

One-line audit wording

Starting material sets the auditable boundary where project traceability and certificate closure begin from a controlled, released input; raw material remains an upstream metallurgical control domain that supports capability rather than forming the piece-level deliverable traceability chain.

FAQ

Q1: What is steel plate in project procurement terms?
A1: Steel plate is flat-rolled steel delivered as individual plates, ordered to a standard and grade with defined steel plate size, steel plate thickness, delivery condition, and verification documents such as MTC and specified NDT.

Q2: How is steel plate weight calculated for logistics and lifting plans?
A2: Steel plate weight is commonly calculated as Length (m) × Width (m) × Thickness (mm) × 7.85, then confirmed by packing list and measured shipping weights.

Q3: Why does steel plate thickness change fabrication risk and inspection scope?
A3: Steel plate thickness affects forming route, weld preparation, heat input control, distortion behavior, and the practicality of NDT coverage, especially on heavy welded assemblies.

Q4: Does steel plate rolling machine mean a mill or a fabrication roller?
A4: Both meanings exist. It can mean the plate mill rolling stand that controls thickness and shape, or the fabrication bending rolls that control cylinder roundness and springback.

Q5: Why does starting material vs raw material matter in documentation?
A5: It defines the traceability boundary. Starting material is the controlled input (slab or released plate) that carries heat identity into certificates and inspection closure, while raw material is upstream of that boundary.

Detailed Technical Description

1.Raw Material Preparation and Blast Furnace Ironmaking：

• Iron Ore Processing: High-quality iron ore is processed through sintering technology to produce sinter
• Blast Furnace Smelting: 500m³ blast furnace reduces iron ore with coke to obtain hot metal
• Temperature Control: Blast furnace tapping temperature controlled at 1450-1500°C to ensure hot metal quality

2.Converter Steelmaking and Refining

• Converter Smelting: 50t converter processes hot metal and scrap steel
• Composition Control: Strict control of C, Si, Mn, P, S content to meet API 5L B standards
• LF Refining: Ladle refining furnace for desulfurization, deoxidation, and composition fine-tuning
• VD Vacuum Degassing: Vacuum degassing furnace removes harmful gases like H₂ and N₂, improving steel purity

3. Continuous Casting

• Continuous Casting Process: Continuous casting technology pours refined molten steel into tube billets
• Fixed Length Cutting: Cutting according to specification requirements
• Controlled Cooling: Control cooling rate to prevent internal stress formation

4.Heating and Rolling

• Hot Charging: Hot charging of billets into reheating furnace to reduce energy consumption
• Reheating Furnace: Heating billets to 1200-1250°C rolling temperature
• High Pressure Water Descaling: Removal of surface oxides to ensure surface quality
• Rough Rolling: 650mm reversing mill for rough rolling formation
• Finish Rolling: 10-stand 550mm continuous mill for precision rolling

5.Finishing and Quality Control

• Step-Type Cooling Bed: Uniform cooling to eliminate residual stress
• Online Inspection: Online surface quality detection system
• Sampling Inspection: Comprehensive inspection of chemical composition and mechanical properties
• Wire Rod Finishing: Straightening and surface flaw detection
• Product Packaging: Bundling, tagging, and warehouse management

Production Facilities & Quality Certification Gallery

Pipe Manufacturing Process

Production Capacity and Product Specificatins

Our company possesses robust production capabilities with an annual total steel output of 600,000 tons, including 400,000 tons of seamless steel pipes, and a monthly capacity of 50,000 tons through 24-hour continuous production operations, capable of meeting large-scale order requirements. Our main products are API 5L B PSL2 seamless steel pipes with outer diameters ranging from 21.3mm to 813mm and wall thickness from 2.5mm to 80mm, strictly controlling chemical composition (C≤0.30%, Mn≤1.40%, P≤0.030%, S≤0.030%, Si 0.15-0.40%) and mechanical properties (yield strength ≥245MPa, tensile strength 415-760MPa, elongation ≥22%) according to API 5L standards. We are equipped with efficient casting furnaces and rolling mills, precision dimension control systems, real-time quality monitoring systems, automated coating equipment, and professional testing equipment, establishing a comprehensive quality assurance system covering chemical composition analysis, mechanical property testing, non-destructive testing, and other comprehensive inspection items. Our products are widely applied in oil & gas, power, mechanical manufacturing, chemical, and construction industries, certified by API 5L, ISO 9001, ISO 14001, and other international standards, providing customers with excellent services including large-volume supply capability, customized production, fast delivery, and complete quality traceability.

Oficinay sucursales

Factory Address: No. 10 Fengyang Road, Luoshe Town, Huishan District, Wuxi City, China
Octal steel Pte.Limitado. Ltd.
Agregar: 8 Kaki Bukit Avenue 4 #03-21 Premier @Kaki Bukit Singapur (415875)
Octal Keerun co.. Ltd.
Dirección: Piso/Habitación 1512, 15.” piso, Lucky Center, n.° 165-171 Wan Chai Road, Wan Chai, Hong Kong
Cooperación internacional de la Industria de Maquinaria de china Co., Ltd.Dirección: Edificio A, n. 18, Carretera Dirun, Nuevo Distrito de Zhengdong, Zhengzhou, Henan, China
Henan Keerun Trading Co., Ltd
Agregar: Unidad 2544, 25/F, Torre A, Centro Wanda, Distrito Wenfeng, Anyang, Henan, China
Octal Enpro (Tianjin) Multinational co., Ltd
Dirección: Edificio Beichen, n.° 4-1114, Tianjin, China
Octal Fujian Keerun Trading Co., Ltd.
Dirección: 23/F, Torre Sur del Centro Guomao, 4686-4688 Xianyue Road, Xiamen, China

Factory Address: No. 10 Fengyang Road, Luoshe Town, Huishan District, Wuxi City, China

The scope of ASTM A106 and A53

ASTM A53 specification covers the steel pipe manufacturing types in seamless and welded, material in carbon steel, black steel. Surface natural, black, and hot-dipped galvanized, zinc coated steel pipe. Diameters range from NPS 1⁄8 to NPS 26 (10.3mm to 660mm), nominal wall thickness.

ASTM A106 standard specification covers the seamless carbon steel pipe, applied for high-temperature services.

Different types and grades for both standard

ASTM A53 steel pipe types and grades

For ASTM A53 there are ERW and seamless steel pipes Type F, E, S covers Grade A and B.

A53 Type F, furnace butt welded, continuous weld Grade A
A53 Type E, Electric resistance welded (ERW), in Grade A and Grade B.
A53 Type S, Seamless steel pipe, in Grade A and Grade B.

If raw steel material of different grades in process of continuously casting, the transition material result shall be identified. And the manufacturer should remove the transition material with the processes that could separate the grades positively.

In case ASTM A53 Grade B in ERW (electric resistance welded) pipe, the weld seam shall be done the heat treatment with a minimum 1000°F [540°C]. In this way the no untempered martensite remains.

In case ASTM A53 B pipe in cold expanded, then expansion should not exceed 1.5% of the required OD.

(Please note the type F is not used for flanging, and if type S or type E is applied for coiling or cold bending, it is recommended to use ASTM A106 Grade A pipe. Although, it is not prohibit to use ASTM A106 Grade B for the cold bending and coiling. According the facility from the manufacturer, type E of ASTM A53 pipe could be supplied non cold expanded or cold expand steel pipe.)

A53 B Chemical and mechanical properties

ASTM A53 Grade B chemical properties content C≤0.30%, Mn≤1.2%, P≤0.05%, S≤0.045%, Cr≤0.40, Cu≤0.40, Ni≤0.40, Mo≤0.40, V≤0.08.
ASTM A53 B mechanical strength is the same with ASTM A106 B steel pipe, Tensile strength maximum 415 Mpa, Yield strength maximum 240 Mpa.
Elongation: For A53 pipe there are 2 methods to calculate elongation.
A: Use equation: e = 625 000 [1940] A^0.2/U^0.9
B: See ASTM A53 elongation value table X4.1 or table X4.2 for different specimen area.

ASTM A106 steel pipe types and grades

For ASTM A106 steel pipe, manufacturing Type only in seamless, processes hot rolled and the cold drawn. Grade in A, B and C.

ASTM A106 Grade A: Maximum Carbon element 0.25%, Mn 0.27-0.93%. Minimum tensile strength 48000 Psi or 330 Mpa, yield strength 30000 Psi or 205 Mpa.
A106 Grade B: Maximum C below 0.30%, Mn 0.29-1.06%. Minimum tensile strength 60000 Psi or 415 Mpa, yield strength 35000 Psi or 240 Mpa.
Grade C: Maximum C 0.35%, Mn 0.29-1.06%. Minimum tensile strength 70000 Psi or 485 Mpa, yield strength 40000 Psi or 275 Mpa.

Differences on mechanical properties

ASTM A53 Grade B mechanical strength is same with ASTM A106 Grade B pipe.

Differences on Chemical properties

From below table listed the differences on chemicals for the three similar pipe:

As ASTM A106 B is the common use, the chemical here we listed is C≤0.3%, Mn 0.29-1.06%, P≤0.035, S≤0.035%, Si>0.1, Cr≤0.40, Cu≤0.40, Ni≤0.40, Mo≤0.40, V≤0.08.

Differently with ASTM A53 B, ASTM A106 B has Si min 0.1%, which A53 B has 0, so A106 B have better heat resistance than A53 B, since Si improve the heat resistance.

A106 Grade B has low sulfur and phosphorus than A53 B, this is better.

Applications for both standards

Both pipes applied for mechanical and pressure systems, transporting steam, water, gas, and etc.

ASTM A53 pipe application

1. Construction, underground transportation, extraction of ground water while building, steam water transportation etc.
2. Bearing sets, machinery parts processing.
3. Electric application: Gas transmission, water power generation fluid pipeline.
4. Wind power plant anti-static tube etc.
5. Pipelines that required zinc coated.

ASTM A106 pipe application

Especially for high temperature services that up to 750°F, and it could substitute ASTM A53 pipe in most of the cases. In some country at least in United States, usually ASTM A53 is for welded pipe while ASTM A106 is for seamless pipe. And if client asked for ASTM A53 they will also offer A106. In China, manufacturer will offer the pipe that comply to three standards ASTM A53 B / ASTM A106 B / API 5L B.

More details about ASTM A53 Grade B
More details for ASTM A106 Grade B
More details about API 5L Pipe.

conclusion

In summary, compared to A53, the ASTM A106 standard defines its suitability for high-temperature, high-pressure services as “power piping” or “process piping” through stricter chemical composition controls, higher mechanical property requirements, and heat treatment regimens that ensure elevated temperature performance. Conversely, ASTM A53 serves as an excellent “general-purpose” pipe for most ambient temperature or low-pressure systems.

Correctly distinguishing and applying these two standards is fundamental to ensuring the safety, reliability, and economy of piping systems. Octal Steel, as a professional carbon steel pipe supplier, provides both seamless and welded pipes conforming to ASTM A53 and A106 standards.

Heat treatment methods for carbon and alloy steel pipe include 4 mainly types: normalizing, annealing, quenching and tempering. It will improve steel material mechanical properties, uniform chemical composition, and machinability.

Heat treatment for steel metal materials can be divided into integral heat treatment, surface heat treatment and chemical heat treatment. Steel pipe generally adopts the integral heat treatment.

Heat treatment purposes for steel pipe

The performance of steel material mainly refers on mechanical properties, physical properties, and process performance. Heat treatment will bring different metallurgical structure and corresponding performance for the steel pipe, so could be better applied in different industrial or the oil gas services.

There are two methods to improve the properties of steel material. One method is to adjust the chemical composition, named alloying method. The other method is heat treatment. In the field of modern industrial technology, heat treatment improve steel pipe performance at dominate position.

Heat treatment procedures.

1. Heating.
The steel material could be heated below the critical point or above critical point. The former heating way can stabilize structure and eliminated the residual stress. The latter way can make material austenitizing.

Austenitizing is to heat steel metal over its critical temperature long time enough, so it could be transformed. If a quenching followed after Austeniting, then the material will be harden. Quenching will take fast enough to transform austenite into martensite. Once reached austenitizing temperature, suitable microstructure and full hardness, the steel pipe material will be attained in further heat treatment processes.

2. Heat preservation.
The purpose of heat preservation is to uniform the heating temperature of steel material, then it will get a reasonable heating organization.

3. Cooling
The cooling process is the key process in heat treatment, it determines mechanical properties of steel pipe after cooling process.

Four main heat treatment methods in carbon and alloy steel pipe industry

The heat treatment processes for steel pipe includes normalizing, annealing, tempering, quenching and other process.

Normalizing

Heating the steel pipe above the critical temperature, and cooled in the air.

Through normalizing, the steel material stress could be relieved, improves ductility and toughness for the cold working process. Normalizing usually applied for the carbon and low alloy steel pipe material. It will produce different metal structure, pearlite, bainite, some martensite. Which brings harder and stronger steel material, and less ductility than full annealing material.

Annealing

Heating the material to above its critical temperature long enough until microstructure transform to austenite. Then slow cooled in the furnace, get maximum transformation of ferrite and pearlite.

Annealing will eliminate defects, uniform the chemical composition and fine grains. This process usually applied for the high carbon, low alloy and alloy steel pipe need to reduce their hardness and strength, refine the crystal structure, improve the plasticity, ductility, toughness and machinablity.

Quenching

Heating the steel pipe material to critical temperature until microstructure transformation is done, cooling it in a rapid rate.
Quenching purpose is to produce the thermal stress and tissue stress. It can eliminate and improve through the tempering. The combination of quenching and tempering can make the comprehensive performance improved.

Tempering

Heating the steel material to a precise temperature below the critical point, and often done in the air, vacuum or the inert atmospheres. There are low temperature tempering 205 to 595°F (400 to 1105°F), medium temperature and high temperature tempering (to 700℃ 1300℉).

The purpose of tempering is to increase the toughness of steel and alloy steel pipe. Before tempering, these steel is very hard but too brittle for the most application. After process can improve the plasticity and toughness of steel pipe, reduce or eliminate the residual stress and stabilize the steel pipe’s size. Brings good comprehensive mechanical properties, so that it does not change in service.

Solution treatment for alloy-based steel pipe material

Solution treatment

Heating an alloy to a proper temperature, preserve it at this temperature long enough to cause or more constituents to change into a solid solution, then cooling it at rapid rate to hold these constituents in solution.

There are various of cast and wrought nickel-based alloys that can achieve different required performances through solution treatment or by precipitation age hardening. Characteristics as room temperature and elevated temperature mechanical strength, corrosion resistance and oxidation resistance will be significantly enhanced by this heat treatment. Many nickel-based alloys develop their desired properties solely through the solution treatment, like Hastelloy and nickel alloy steel pipe.

During solution treatment, the carbide and various alloying elements are dissolved uniformly in the austenite. Cooling rapidly will make carbon and alloy elements too late to precipitate, and obtain the heat treatment process of single austenite tissue. The solution treatment can uniform internal structure and chemical compostion. It can also restore the corrosion resistance for Hastelloy and nickel alloy steel pipe.

What is EN 10204 means?

When we purchasing steel products like seamless pipe, pipe fittings, sucker rod or steel plates,  manufacturer should release the MTC to the buyer. MTC is Mill Test Certificate, it contains all the specification of the steel pipe products. Including dimensions, sizes, weight, chemical composition, mechanical strength, heat treatment status, test result, traceability etc. These information is to make sure the quality of ordered steel products, tells the buyer what situations could be applied in engineering purposes. So the certificate standard for the MTC is generated, EN 10204 is European standard for the inspection documents for the steel products including steel line pipe, fittings, steel plate, valves, sucker rods etc. For certifying the results of the specific test is complied with client’s order.

Differences between EN 10204-3.1 and 3.2 for the MTC

EN 10204 contains 4 types of document type, 2.1, 2.2, 3.1 and 3.2. Type 2.1 and 2.2 are validated by the manufacturer. Type 3.1 and 3.2 are not only validated by manufacturer.
Type 2.1, The content is statement of compliance with the order. Validated by manufacturer.
Type 2.2, Statement of compliance with the order, with indication of results of non specific inspection. Validated by manufacturer.
Type 3.1, Statement of compliance with the order, with indication of results of specific inspection. Authorized inspection representative by the manufacturer, but is independent of the manufacturing department.
Type 3.2, Statement of compliance with the order, with indication of results of specific inspection. Authorized inspection representative by the manufacturer, independent of manufacturing department and either the buyer’s authorized inspection representative or the inspector designated by the official regulations.

EN 10204-3.1 type quality certificate.

It requires the manufacturer to show the actual test result for the steel pipes on sale. According the related standard sampling methods.

3.1 MTC requires the test agency shall be an independent party, mill has no rights to revise the test results.

If a steel pipe manufacturer passed the audit for the ISO 9001 from a certification agency of European Union, then this manufacturer have the qualification to release the EN 10204-3.1 MTC. The buyer information shall be specified on the MTC quality certificate, and one buyer need one MTC quality certificate. If the manufacturer didn’t pass ISO 9001 or the ISO 9001 certificate not from European Union Inspection Agency, then the manufacturer do not have right to release MTC of EN 10204-3.1. In this case, manufacturer shall apply for the EN 10204-3.2 quality certificate from the third part of inspection agency.

EN 10204-3.2 type quality certificate.

EN 10204 3.2 certificate is the most restrict standard level for the steel pipe products.It indicates the certification shall be additional countersigned and verified by independent related all the tests, 3.2 certificate cost higher than 3.1. Not only manufacturer test department, but also a completely independent part. Third party inspector, or the personal, buyer, or government’s representative also have right to verify the test results.

EN 10204-3.2 certificate must released by the inspection agency that authorized by the European Union. Through the related inspection or the test for the material that ordered, to certify that the test result is the same with the PO from a third party inspection agency. Also on the quality certificate of EN 10204-3.2 shall specify the name of manufacturer and the buyer.

EN 10204 certificate related steel pipe MTC in following specs.

• Chemical composition
• Mechanical strength
• Impact strength
• Tensile strength
• Hardeness test
• Bend test
• NDE
• Visual and Dimensions
• Hydro test
• NDT test
• Magnetic test
• Pipe end
• Corrosion HIC status
• Heat no