Quality Control
Table of Contents
Testing Standards & Certification
Nonleak adheres to comprehensive international, national, and industry standards to ensure every product meets the highest quality requirements.
Enterprise Standard
Nonleak Enterprise Standard Q09297288-5·1-2020
Stainless Steel Pipes Standard
Size Range: DN15-DN350
Standard: *GB/T12771-2019 “Stainless Steel Welded Pipes for Fluid Transportation”*
Stainless Steel Pipe Fittings Standard
Threaded Press-Fit Connection
Size Range: DN15-DN100
Applicable Standards:
Q/9297288-5.1-2014 “Stainless Steel Threaded Press-Fit Fittings”
HG/T3737-2018 “Single-Component Anaerobic Adhesive”
JB/T7311-2008 “Technical Specification for Application of Anaerobic Adhesive, Silicone Rubber and Dry Film Pre-coating in Construction Machinery”
DBJ51/T 023-2014 “Technical Specification for Thin-Walled Stainless Steel Pipeline with Press-Fit Adhesive Connection for Gas”
CECS 423:2016 “Technical Specification for Thin-Walled Stainless Steel Pipeline with Adhesive Connection”
- ASME B16.11
Orbital Press Connection
Size Range: DN15-DN100
Applicable Standards:
GB/T33926-2017 “Stainless Steel Orbital Press Fittings”
CJJ94-2009 “Code for Construction and Quality Acceptance of Indoor Gas Engineering”
DB51/T5035-2012 “Technical Specification for Thin-Walled Stainless Steel Pipeline with Orbital Press Connection for Gas”
GB/T23658-2009 “Elastomeric Seals – Material Requirements for Seals Used in Pipes and Fittings for Transporting Gaseous Fuels and Hydrocarbon Liquids”
HG/T3092-1988 “Rubber Seal Compounds for Gas Transmission Pipes and Fittings”
- EN 10312, ISO 15835, AS/NZS 4128
Double-Press Connection
Size Range: DN15-DN100
Applicable Standards:
GB/T 19228.1-2011 “Stainless Steel Press-Fit Fittings – Part 1: Press-Fit Fittings”
GB/T 19228.2-2011 “Stainless Steel Press-Fit Fittings – Part 2: Stainless Steel Tubes for Connections”
GB/T19228.3-2012 “Stainless Steel Press-Fit Fittings – Part 3: O-Ring Rubber Seals”
- EN 10312, ISO 15835, AS/NZS 4128
- For product configurations within this connection family, review Nonleak’s Double Press Fittings range. The exact fitting type, size, material, seal, tooling and project documentation should be confirmed before specification.
Testing & Inspection Standards
Mechanical Properties
Tensile Strength: ≥520 MPa
Elongation: ≥35%
Eddy Current Testing: Compliant with GB/T7735 Grade A
Flattening Test: No cracks or fractures when compressed to 1/3 of pipe diameter
Stress Testing
Fitting Pressure Test: >1.05 MPa (each product individually tested)
System Pressure Test: 2.5 MPa for 14 hours (no leakage at connections)
For pressure-boundary bolted flange joints, our ASME PCC-1 flange assembly guide explains the relationship between pre-assembly inspection, alignment, gaskets, bolting, tightening and joint records.
Third-Party Certification
Sichuan Provincial Center for Disease Control and Prevention
Product Tested: Nonleak Stainless Steel Welded Pipes for Fluid Transportation
Result: Fully compliant with all specified standards and regulations
National Building Materials Product Quality Inspection Center
Product Tested: Nonleak Stainless Steel Manifolds
Result: Meets all national quality standards and performance requirements
Product Tested: Nonleak Threaded Press-Fit Pipeline System
Key Finding: 70-year service life certification
Result: Verified long-term durability and performance reliability
Product Conformity Documentation
CE / CPR Documentation — Double Press Fittings
Nonleak maintains CE / CPR conformity documentation for defined stainless steel Double Press fitting products and intended-use scopes.
The applicable documentation identifies the covered product configuration, declared performance, intended uses and supporting technical requirements. Because conformity scope can vary by product model, size and application, the current document should be reviewed before project specification.
- Product Family: Stainless Steel Double Press Fittings
- Documentation: CE / CPR conformity and Declaration of Performance documentation
- Scope: According to the current applicable product documentation
- Availability: Provided for project and compliance review on request
Application and Project Validation
Product standards, test records and conformity documentation provide one layer of technical evidence. Completed project supplies provide another: they show how Nonleak products have been manufactured and delivered in real construction projects at defined quantities and project scales.
The following projects are documented examples of Nonleak 304 stainless steel pipe and Double Press fitting supply in China.
Double Press Project References
- 2018 — Hongbao Jinxiu Riverside, Ningxia: 75,103 meters of 304 stainless steel pipe and 41,620 Double Press fittings. View project case
- 2021 — Chengdu Qingbaijiang District Hospital of Traditional Chinese Medicine: 459,870 meters of 304 stainless steel pipe and 367,891 Double Press fittings. View project case
- 2022 — Baoji Central Hospital Port Area Branch: 132,980 meters of 304 stainless steel pipe and 100,095 Double Press fittings. View project case
Together, these references demonstrate Double Press project supply across different building types, project years and procurement volumes.
Project experience and product conformity are separate forms of evidence. A previous project does not automatically establish suitability or regulatory approval for a future installation. The exact product model, material, sealing element, service medium, operating conditions, local regulations and project requirements must be confirmed independently.
For current product configurations and project selection information, review our stainless steel Double Press fittings.
Our Quality Commitment
To Our Valued Customers:
At Nonleak, quality is not just a process — it’s our promise. We guarantee:
Every Product Tested: Each pipe and fitting undergoes rigorous pressure, material, and performance testing
Leak-Proof Performance: Our patented connection technologies ensure zero leakage throughout the system lifecycle
Long-Term Reliability: Certified 70-year service life for sustainable, maintenance-free operation
Complete Traceability: From raw material to finished product, full documentation and tracking
Continuous Improvement: Ongoing quality monitoring and process optimization