Special Equipment Manufacturing License for Pressure Vessels and Pressure Piping Components (TS Certification)
1. Definition and Regulatory Principles
The Special Equipment Manufacturing License (特种设备制造许可证), commonly referred to as the "TS License," is the mandatory regulatory authorization issued by the State Administration for Market Regulation (SAMR) of the People's Republic of China. Under the Special Equipment Safety Law of the People's Republic of China (《中华人民共和国特种设备安全法》) and the Special Equipment Safety Supervision Regulations (《特种设备安全监察条例》), any entity manufacturing pressure vessels, pressure piping components, or composite-clad equipment intended for industrial service must obtain this license before commencing commercial production.
The TS License is not a voluntary quality mark but a statutory prerequisite. Without it, the manufacture, installation, or delivery of pressure-containing equipment is illegal, and any product produced without the license is subject to confiscation, fines, and potential criminal liability. The license is structured in a tiered system (分级许可) that delineates the scope of permitted manufacturing activities by equipment category, design pressure, design temperature, material class, and process method.
For composite (clad) equipment manufacturers specifically, the TS License carries additional granularity: the cladding/weld-overlay process range must be explicitly listed in the license detail sheet (许可明细), specifying permitted base materials, overlay materials, process types (e.g., explosion welding, hydraulic explosive bonding, TIG/MIG weld overlay), thickness limits, and applicable product forms (vessels, piping, flanges, etc.).
2. Category Classification and Business Positioning
2.1 License Category Structure
The TS License for pressure equipment is divided into two primary categories relevant to composite/clad equipment manufacturing:
- Category A – Pressure Vessel Manufacturing (压力容器制造): Covers fixed pressure vessels, including those fabricated from composite plates (爆炸复合板、液压爆炸复合板、堆焊复合板). Sub-categories include A1 (super-high pressure), A2 (high pressure), A3 (medium/low pressure), and F (fiber-reinforced).
- Category B – Pressure Piping Component Manufacturing (压力管道元件制造): Covers piping, flanges, valves, and fittings, including clad pipes (衬里管) and composite pipe components.
2.2 Tiered Licensing (分级许可) Framework
| License Tier | Pressure Vessel Scope | Typical Composite Applications | Issuing Authority |
|---|---|---|---|
| A级 (Class A) | Design pressure ≥ 1.6 MPa; all vessel types including composite-lined reactors, heat exchangers | Explosion-welded composite plate reactors, hydraulic bonded pressure vessels | SAMR (National Level) |
| B级 (Class B) | Design pressure ≥ 0.1 MPa; limited vessel categories | Composite-lined storage tanks, medium-pressure exchangers | Provincial Market Regulation Bureau |
| GC1 (Piping Class 1) | Longitudinal pressure piping components, including clad pipe spools | Explosion-welded clad pipes for high-temperature/high-pressure service | SAMR (National Level) |
| GC2/GC3 (Piping Class 2/3) | Lower-parameter piping components | Weld-overlay-lined pipes, hydraulic bonded piping | Provincial Market Regulation Bureau |
2.3 Business Positioning
For Cladding Technology Shanxi Co., Ltd., the TS License serves as the gateway credential that enables commercial participation in regulated industries—petrochemicals, power generation, nuclear-adjacent applications, and pharmaceutical manufacturing—where pressure equipment is subject to mandatory government oversight. The license transforms the company from a technical service provider into a legally authorized manufacturer capable of delivering stamped, certifiable products into the regulated supply chain.
3. Technical Purpose and Strategic Value
3.1 Enabling Product Delivery
The TS License directly enables the following commercial capabilities:
- Manufacture and delivery of composite-plate pressure vessels (爆炸复合板压力容器) that bear the manufacturer's stamp and accompany a full inspection dossier.
- Production of clad piping components (衬里管) with traceable quality records accepted by EPC contractors and end-users.
- Execution of weld-overlay (堆焊) operations on pressure-containing equipment within the licensed process scope, ensuring overlay layers are recognized as integral components of the pressure boundary.
- Eligibility to serve as a subcontractor or prime contractor on projects requiring TS-certified fabrication.
3.2 Customer Value Proposition
For customers in regulated industries, the TS License provides:
- Regulatory compliance assurance: Products manufactured under a valid TS License are accepted by inspection agencies (特种设备检验院) for mandatory in-service inspection.
- Reduced project risk: Eliminates the need for project-specific exemptions or post-fabrication compliance remediation.
- Insurance and audit acceptability: Insurance providers and corporate auditors recognize TS-certified equipment as meeting minimum safety standards.
- Supply chain qualification: Major EPC contractors (e.g., China Petrochemical Engineering, China National Chemical Engineering) require TS License verification as a prerequisite for vendor registration.
3.3 Qualification Building
The TS License is not merely a standalone credential but forms the foundation layer of a broader qualification architecture. It enables subsequent pursuit of:
- ASME U Stamp or U2 Stamp for international market access.
- NB License (核级) for nuclear-grade pressure equipment.
- API Monogram (e.g., API 5CT for clad tubing, API 5L for clad pipe) for oil and gas applications.
- ISO 3834-2 weld execution certification as a complementary quality system.
4. Key Implementation Points and Process Requirements
4.1 Application and Approval Process
- Pre-application preparation: Compile organizational structure, personnel qualifications (welders, NDT technicians, quality engineers), equipment inventory, and facility documentation.
- WPS/PQR Qualification: Complete Welding Procedure Qualification Records for all cladding/weld-overlay processes to be included in the license scope, per TSG 11-2020 (《固定式压力容器安全技术监察规程》).
- Application submission: File with SAMR or the competent provincial authority, including product samples and process demonstration records.
- On-site audit (现场鉴定): Regulatory auditors inspect facility, personnel, equipment, quality system, and witness trial production of representative products.
- Product inspection: Submitted products undergo full NDT and dimensional verification by the designated inspection agency (特种设备检验机构).
- License issuance: Upon satisfactory completion, the TS License is issued with defined scope, validity period (typically 4 years), and enumerated process ranges.
4.2 Process Scope Definition in License Detail
The license detail sheet (许可明细) must explicitly enumerate:
| Parameter | Definition Requirement | Example Entry |
|---|---|---|
| Process Type | Cladding method(s) authorized | Explosion welding (爆炸复合), Hydraulic explosive bonding (液压爆炸复合), TIG/MIG weld overlay (堆焊) |
| Base Materials | Material grades permitted | Q345R, 16MnR, 09MnNiDR, SA-516 Gr.70, 304/316L stainless |
| Overlay/Clad Materials | Corrosion-resistant materials authorized | 304, 316L, 321, Hastelloy C-276, Inconel 625, Titanium Gr.2 |
| Minimum Clad Thickness | Thinnest overlay layer covered | ≥ 1.5 mm (weld overlay), ≥ 0.5 mm (explosion welding) |
| Maximum Clad Thickness | Thickest overlay layer covered | ≤ 50 mm (explosion welding), ≤ 30 mm (weld overlay) |
| Product Form | Equipment types permitted | Composite plate vessels (复合板容器), Clad pipes (衬里管), Composite flanges |
| Pressure/Temperature Range | Design parameter limits | P ≤ 4.0 MPa, T ≤ 450°C (example) |
4.3 Quality Management System Requirements
The TS License mandates a documented quality management system aligned with TSG 07-2019 (《特种设备生产和充装单位许可规则》), which requires:
- Document control: All manufacturing procedures, inspection records, and NDT reports must be traceable to specific serial numbers.
- Personnel qualification maintenance: Welder qualifications (按 GB/T 3375), NDT Level II/III certifications (按 GB/T 19420), and quality engineer credentials must remain current.
- Equipment calibration: All welding power sources, NDT equipment, dimensional measurement tools, and pressure testing apparatus must be under valid calibration.
- Material traceability: Full material certification (MTC) tracking from mill to finished product, including composite plate interface verification records.
- Nonconformance management: Documented procedures for deviation handling, rework approval, and disposition of rejected components.
5. Applicable Standards and Acceptance Criteria
5.1 Governing Regulatory Standards
| Standard/Regulation | Title | Relevance to TS License |
|---|---|---|
| TSG 11-2020 | Technical Safety Regulations for Fixed Pressure Vessels | Primary design and manufacturing code for pressure vessels including composite-clad vessels |
| TSG 21-2016 | Supervision Regulations for Pressure Piping | Governs pressure piping components including clad pipe |
| TSG 07-2019 | Rules for Licensing of Special Equipment Production and Filling Units | Defines licensing procedures, audit criteria, and quality system requirements |
| GB/T 150.1-2011 | Pressure Vessels – Part 1: General | Design and fabrication requirements for vessels including composite construction |
| GB/T 150.4-2011 | Pressure Vessels – Part 4: Fabrication, Inspection and Acceptance | Manufacturing, NDT, and acceptance criteria |
| GB/T 18449-2017 | Explosion Welded Clad Plates – Requirements | Product specification for explosion-welded composite plates used in pressure equipment |
| GB/T 19542-2004 | Weld Overlaying on Steel Parts | Weld overlay process requirements for corrosion-resistant linings |
| JB/T 4714-2019 | Explosion-Welded Clad Plates for Pressure Vessels | Industry standard for explosion-welded plates in pressure vessel service |
5.2 Acceptance Criteria for Composite Equipment under TS License
Products manufactured under the TS License must meet the following acceptance criteria:
- Interface bonding quality: Explosion-welded interfaces must achieve ≥ 90% bonded area per GB/T 18449 and ASTM A407; hydraulic explosive bonded interfaces verified per applicable internal specifications aligned with ASTM A240 clad plate requirements.
- Weld overlay continuity: Overlay layers must be continuous, free of undercut, porosity, or lack of fusion, verified by magnetic particle inspection (MT) per GB/T 26952 or ultrasonic testing (UT) per GB/T 11345.
- Weld joint quality: All pressure boundary welds must pass NDT at the percentage and acceptance level specified in GB/T 150.4 (typically 100% RT for Category I/II vessels).
- Dimensional compliance: Vessel dimensions, flange dimensions, and pipe geometry must conform to GB/T 150, GB/T 12459 (bends), and GB/T 12460 (welded fittings).
- Pressure testing: Hydrostatic test at 1.25× design pressure (or 1.5× for composite vessels per GB/T 150.4 Section 8.6), with no visible leakage or permanent deformation.
6. Common Risks and Control Measures
6.1 License Scope Violation Risk
Risk: Manufacturing products outside the enumerated process scope in the license detail (e.g., using a material grade or cladding thickness not listed).
Control: Implement a license scope matrix that cross-references every product order against the license detail. Establish a pre-production gate review requiring quality engineering sign-off confirming full scope compliance before material release for fabrication.
6.2 Personnel Qualification Lapse
Risk: Welders, NDT technicians, or quality engineers operating beyond their qualification validity period, rendering all work performed non-compliant.
Control: Maintain a personnel qualification database with automated expiry alerts at 90 days, 60 days, and 30 days before lapse. Implement a policy prohibiting assignment of unqualified personnel to licensed operations.
6.3 Audit Nonconformance
Risk: During periodic surveillance audits (监督检验), auditors identify systemic quality management deficiencies leading to license suspension or scope reduction.
Control: Conduct internal mock audits annually using the TSG 07-2019 audit checklist. Maintain corrective action closure rates ≥ 95% with documented root cause analysis. Assign a dedicated TS License compliance officer.
6.4 Process Capability Drift
Risk: Changes in equipment, consumables, or operator skill levels degrade cladding process capability without triggering requalification.
Control: Implement process monitoring parameters (e.g., explosion velocity, impact angle, overlay welding current/voltage) with statistical process control (SPC) limits. Require requalification (PQR) upon any change exceeding defined thresholds per ASME Section IX or TSG 11-2020 Annex.
6.5 Material Traceability Gaps
Risk: Inability to trace composite plate material certifications through to finished product, failing mandatory inspection requirements.
Control: Implement a material traceability system linking mill certificates, incoming inspection reports, composite plate heat numbers, fabrication serial numbers, and final product data sheets. Use barcode/RFID tracking for critical material flow.
7. Application Across Three Technology Routes
7.1 TIG/MIG Weld Overlay Route
Under the TS License, TIG and MIG weld overlay processes are authorized as cladding methods for pressure boundary components. The license enables:
- Application of multi-pass overlay linings (typically 3–6 passes) on pressure vessel internals, heat exchanger tubesheets, and pipe spools, with overlay thickness ranging from 1.5 mm to 30 mm.
- Use of transition layers (e.g., 309L between carbon steel and 316L) to manage thermal expansion mismatch, with the full overlay sequence documented in the WPS and recorded in the product data file.
- NDT verification of overlay layers using MT (surface defects) and UT (lack of fusion, porosity) at levels specified in GB/T 19542 and TSG 11-2020.
- Delivery of overlay-lined pressure vessels with full traceability from base plate certification through final overlay inspection.
License-specific requirement: The WPS/PQR for each overlay process must be qualified per GB/T 19542 and included in the license application dossier. The overlay process is treated as a pressure boundary manufacturing operation, requiring the same level of NDT and documentation as base weld joints.
7.2 Hydraulic Explosive Bonding Route
The TS License authorizes hydraulic explosive bonding (液压爆炸复合) as a composite plate manufacturing process for pressure equipment. Key implementation points:
- Production of composite plates with base layers up to 100 mm and clad layers from 0.5 mm to 50 mm, suitable for large-diameter pressure vessels and heat exchangers.
- Post-bonding annealing (typically 750–900°C for austenitic stainless clad) to relieve residual stresses and ensure metallurgical compatibility, with heat treatment parameters recorded per the WPS.
- Interface bond strength verification via peel test or bend test per GB/T 18449 and ASTM A407, with results attached to the product inspection dossier.
- Application to pressure vessels requiring large-format composite plate (up to 6000 mm × 3000 mm) that cannot be economically produced by explosion welding alone.
License-specific requirement: The hydraulic explosive bonding process must be demonstrated during the on-site audit with a trial product subjected to full NDT (UT for interface bonding, MT/PT for surface defects). The process parameters (water pressure, explosive charge configuration, impact velocity) must be documented and controlled.
7.3 Explosion Welding Route
Explosion welding (爆炸复合) is the company's primary high-integrity cladding process, fully covered under the TS License for pressure equipment manufacturing. The license enables:
- Production of explosion-welded composite plates meeting GB/T 18449 and JB/T 4714 specifications, with interface bonding integrity verified by ASTM A407 methods.
- Fabrication of pressure vessels from explosion-welded composite plates where the clad layer forms part of the corrosion-resistant pressure boundary, requiring the vessel to be designed per GB/T 150.1 composite construction rules.
- Manufacture of clad pipe components (衬里管) where explosion-welded pipe blanks are machined to final dimensions, with the composite interface verified by UT per GB/T 11345.
- Production of composite flanges, heads, and other pressure piping components where explosion-welded forgings or plates are formed and welded into final geometry.
License-specific requirement: The explosion welding facility must be inspected during the TS License audit, including verification of explosive storage compliance, safety zoning, detonation control systems, and post-explosion inspection procedures. Each explosion-welded batch requires an explosion record documenting charge weight, spacing, impact velocity, and post-explosion interface inspection results.
8. Strategic Recommendations for License Optimization
8.1 Scope Expansion Strategy
- Year 1: Secure initial TS License for Class A pressure vessels with explosion welding and TIG/MIG weld overlay processes, covering common material combinations (carbon steel + 304/316L).
- Year 2: Expand scope to include hydraulic explosive bonding and exotic overlay materials (Hastelloy, Inconel, Titanium).
- Year 3: Pursue GC1 pressure piping license for clad pipe spools and add nuclear-adjacent material grades (e.g., 316H, 904L).
- Year 4: Initiate NB License (nuclear grade) application for nuclear pressure vessel components, leveraging existing TS infrastructure.
8.2 Integration with International Certifications
The TS License infrastructure (quality management system, personnel qualifications, equipment calibration, WPS/PQR database) provides a direct foundation for pursuing international certifications:
- ASME U Stamp: Map TSG 11-2020 requirements to ASME Section VIII Div. 1/2; leverage existing NDT personnel and welding procedures.
- API 5L/5CT Monogram: For clad pipe and tubing products, the TS License manufacturing discipline directly supports API quality system requirements.
- ISO 3834-2: The TS quality system already exceeds ISO 3834-2 requirements; certification is primarily a documentation alignment exercise.
8.3 Customer-Facing Value Communication
To maximize the commercial value of the TS License, the company should:
- Develop a TS License capability matrix presented to customers during vendor qualification, clearly showing process scope, material coverage, and parameter ranges.
- Include TS License number and scope in all product data sheets and inspection dossiers delivered with finished products.
- Offer customers access to the license scope verification report for each order, confirming that the specific product falls within the licensed scope.
- Maintain a public-facing compliance page displaying valid TS License details, valid through the next surveillance audit cycle.
9. Conclusion
The Special Equipment Manufacturing License (TS License) for pressure vessels and pressure piping components is the non-negotiable regulatory foundation upon which all commercial cladding technology operations in China's regulated industries rest. For Cladding Technology Shanxi Co., Ltd., this license transforms technical capability in explosion welding, hydraulic explosive bonding, and weld overlay from laboratory or pilot-scale demonstration into production-ready, inspectable, and deliverable commercial products.
The tiered licensing framework demands disciplined scope management, rigorous quality system maintenance, and continuous personnel qualification. However, when properly leveraged, the TS License becomes a competitive differentiator—enabling participation in high-value projects in petrochemicals, power generation, and process industries where regulatory compliance is a prerequisite for supplier qualification. The license also serves as the structural backbone for pursuing international certifications, positioning the company for global market expansion.