1. Project Overview

This project is a long-term pipeline anti-corrosion and wear-resistant upgrade implemented in the Shengtuo Oil Production Plant, Shengtuo Oilfield, China, one of the most challenging high water cut and high sand content oilfields.

Since 1997, Guangdong Kejin New Materials Co., Ltd. has provided PAMC reinforced MC nylon pipes and nylon steel-lined composite pipes for ground gathering and transportation systems.

Over time, the solution has been deployed across 7 combined stations, with a total installed pipeline length of 23,191 meters, operating continuously for up to 25 years in some sections.

The project has become a benchmark case for oilfield pipeline wear resistance, sand erosion control, and long-life corrosion protection.

2. Industry Challenges in Shengtuo Oilfield

2.1 Severe sand erosion and abrasion

Due to extremely high water cut and sand content in produced fluids, conventional steel pipelines suffer continuous internal abrasion, especially at the bottom of pipelines, leading to rapid wall thinning and perforation.

• Average service life of steel pipelines: ~2 years

• Worst cases: failure within 7–8 months

2.2 Frequent leakage and high maintenance cost

Pipeline perforation occurs frequently every year, causing:

• High maintenance and replacement cost (~5 million RMB/year)

• Risk of crude oil leakage and environmental pollution

• Production interruption and safety hazards

2.3 Limitations of conventional materials

Traditional materials such as carbon steel pipes and FRP pipes fail under long-term oilfield conditions due to:

• Poor wear resistance under sand flow

• Insufficient corrosion resistance

• Aging and delamination issues in composite materials

2.4 Safety constraints in station construction

Combined stations are high-risk production areas:

• Hot work (welding) is strictly restricted

• Long shutdown periods are not acceptable

• Construction safety requirements are extremely high

2.5 Large-diameter pipeline complexity

The system includes large-diameter pipelines with:

• High mechanical stress

• Complex installation conditions

• High reliability requirements for long-distance transport

3. Engineering Solution

To address severe sand erosion, corrosion, and safety constraints, a full-system upgrade was implemented using PAMC reinforced MC nylon pipeline systems.

3.1 Selected materials

• PAMC reinforced MC nylon pipe (for high wear zones)

• Nylon steel-lined composite pipe (for high-pressure and large-diameter sections)

3.2 System-wide replacement scope

The upgrade covered key process areas including:

• Well drainage pipelines in combined stations

• Separator inlet and outlet lines

• Valve group systems

• Produced water and sewage treatment pipelines

3.3 Flange connection system (no hot work)

All pipelines use flange connections, which provide:

• No welding or open flame required

• Fast installation and maintenance

• High operational safety in active production zones

3.4 Continuous material optimization

The outer anti-corrosion layer has been continuously upgraded to improve:

• External corrosion resistance

• Long-term aging resistance

• Dual protection (internal + external corrosion)

4. Core Technical Advantages

4.1 Excellent wear and corrosion resistance

Reinforced MC nylon structure provides outstanding resistance to:

• Sand erosion

• Oil-water mixture corrosion

• Chemical attack in produced fluids

Service life is more than 10 times longer than carbon steel pipelines in similar conditions.

4.2 Integrated one-piece structure

Manufactured by centrifugal casting:

• No delamination or layered structure

• No leakage at interfaces

• High dimensional stability under long-term load

4.3 Low friction inner surface

The smooth inner wall significantly reduces:

• Flow resistance

• Pressure loss

• Energy consumption in transportation

4.4 Lightweight and easy installation

Compared with steel pipes:

• Weight reduced to approximately 1/7

• No heavy lifting equipment required

• Faster installation and lower safety risk

4.5 Steel–nylon composite strength

The composite structure combines:

• Steel strength for pressure and impact resistance

• Nylon lining for corrosion and abrasion resistance

Suitable for large-diameter and high-stress pipeline systems.

4.6 Long service life for full lifecycle operation

Designed for both surface and buried applications with stable operation up to 25 years.

5. Project Implementation Timeline

• 1997: First pilot applications in single-well pipelines

• 2000–2004: Large-scale deployment in multiple combined stations

• 2013–2020: Expansion into water distribution and sewage systems

• 2022–2023: Full-scale upgrade across 7 combined stations

6. Application Scale

Total installed length: 23,191 meters

• Oil gathering pipelines: 5,361 m

• Oil-water mixed transportation: 16,580 m

• Sewage pipelines: 1,250 m

7. Operational Performance

• Continuous stable operation for up to 25 years in some pipeline sections

• Steel pipelines in the same environment failed multiple times during the same period

• No significant wear observed in elbows, reducers, and valve areas

• Maintenance frequency reduced dramatically

• Emergency repair efficiency significantly improved due to no-hot-work installation

8. Economic and Safety Benefits

• Total project investment: ~10.6 million RMB

• Cumulative economic benefit: ~9.2 million RMB and increasing

Key improvements:

• Annual maintenance cost reduced from frequent repairs to near zero

• Eliminated leakage-related losses and environmental risks

• Reduced unplanned shutdowns and production losses

• Significantly improved operational safety in high-risk zones

9. Key Engineering Highlights

• 25-year proven service life in high sand oilfield conditions

• Designed specifically for sand erosion and abrasion control

• Flange connection system eliminates hot work risks

• Suitable for large-diameter and high-pressure pipelines

• Dual anti-corrosion protection (internal + external)

• Full lifecycle cost significantly lower than steel pipelines

• Validated across 7 combined stations and 23,000+ meters