Application Areas       

 Specific scenarios                                                                 

 Core Requirements                                                                 

 Case/Basis                                                                 

 Municipal water supply/drainage  

 Urban trunk water supply pipes, drainage pipe networks, and sewage treatment plant discharge pipes                                  

 Corrosion resistance, high pressure bearing, large flow rate, water quality safety must be guaranteed                                      

 Nantong Xinkai South Road DN1000 main water supply pipeline repair project (tap water delivery); municipal drainage pipe connection requirements

 Petrochemical        

 Transporting oil, natural gas, chemical media (such as compressed air, nitrogen)                              

 Corrosion resistance (especially chloride ions, sulfides), high pressure resistance                                        

 S30408 material pipes are used for compressed air/nitrogen delivery (pressure 0.1-0.6MPa)               

Electricity and Heat      

 Power plant steam pipelines, thermal network (hot water/high temperature fluid)                                   

 High temperature resistance and thermal fatigue resistance                                                            

When transporting steam/hot water, the outlet temperature must be ≤38°C to prevent microbial corrosion                          

 Water Conservancy Project        

 Reservoir flood discharge pipes, agricultural irrigation main pipes, seawater desalination water pipes                                  

Resistant to hydraulic shock and seawater corrosion                                                      

 Used to transport high-salinity media in seawater desalination projects                         

 Industrial water supply        

Factory cooling water system, fire protection pipe network                                                    

 Anti-scaling and vibration-resistant                                                              

The cooling water system needs to control the chloride ion concentration to prevent pitting corrosion            

1. 
   

   Corrosion failure (highest proportion)

   - Pitting (hole corrosion)

   Cause: Chloride ions (Cl⁻) in water destroy the stainless steel passivation film, locally form corrosion holes and penetrate the pipe wall.

   Characteristics: The leakage point is in the shape of a small hole, and yellow-brown corrosion products (containing Fe, O, Cl and other elements) can be seen on the inner wall.

   Cause: Water accumulation in the trench (such as weak alkaline water with pH=7.6 still contains Cl⁻), seawater medium, and residual chlorine-containing water after pressure testing.

   - Stress corrosion cracking (SCC)

   Cause: Cl⁻ + tensile stress (such as welding residual stress, installation stress) work together to cause cracks.

   High-incidence scenarios: weld periphery, baffle contact point, high temperature and high pressure environment.

   - Electrochemical corrosion

   Cause: Pipeline contacts stray current (such as broken wires), different metal contacts form a potential difference, accelerating local corrosion.

   Characteristics: The pitted corrosion area is accompanied by yellow spots (containing Na, Mg, S and other elements).

DN100-3000mm stainless steel pipe weld leakage, corrosion leakage, pitting, crack leakage repair stainless steel straight pipe pipe repair clmap, 304 stainless steel, 316 stainless steel, 316L stainless steel

8.0mpa

2.Welding and material defects

- Weld quality problems: Incomplete penetration and pores in argon arc welding expand into cracks under pressure fluctuations.

- Parent material defects: Inclusions and microcracks in steel pipe manufacturing, cracks during settlement or vibration.

DN100-3000mm stainless steel elbow leakage, 90 degree stainless steel pipe leakage, elbow crack, stainless steel elbow pipe repair clamp, 304 stainless steel, 316 stainless steel, 316L stainless steel

8.0mpa

3.Mechanical damage and installation problems

- Vibration wear:

The pipe collides with the baffle/pipe trench hard objects, causing the pipe wall to thin and crack (especially in large-diameter pipes such as DN1000, which are prone to vibration due to insufficient support).

- Interface slippage:

The sealing of the large-diameter pipe (DN≥1000) connection fails due to long-term settlement, and the casing is separated from the pipe body.

- Installation stress:

Forced assembly during closing generates residual stress that accelerates corrosion.

DN100-3000mm stainless steel tee leakage, any diameter tee pipe leakage, stainless steel tee pipe repair clamp, 304 stainless steel, 316 stainless steel, 316L stainless steel

8.0mpa

4. Environmental and operation and maintenance factors

   - Microbial corrosion:

   When the water temperature is greater than 38℃, microbial growth accelerates, producing acidic metabolites that corrode the pipe wall (common in cooling water systems).

   - External medium intrusion:

   Water in the trench contains sulfides, oxides, or stray currents in the soil, which can cause corrosion.

DN100-3000mm stainless steel pipe opening, stainless steel opening tee for maintenance, 304 stainless steel, 316 stainless steel, 316L stainless steel

Saddle Clamp 316 Flange Type Pn-16

Saddle Clamp 304 Flange Type Pn-16

Saddle Clamp 316L Flange Type Pn-16

1.6mpa