News Details

1、 Material and structure design: breakthrough of double technical barriers of anti-static and anti-aging

The core competitiveness of API standard DN50 hydraulic filling hose comes from the deep integration of its anti-static and anti-aging technologies. The inner lining layer adopts a composite material of fluororubber (FKM) and conductive carbon black. Fluororubber provides excellent oil resistance (can withstand 95 # gasoline, 0 # diesel, and ethanol gasoline), and conductive carbon black (content 15% -20%) stabilizes the surface resistivity at 10 ⁶ -10 ⁸ Ω, meeting the static electricity safety requirements of the explosion-proof zone (Zone 1) of gas stations. Laboratory tests have shown that when transporting gasoline containing 10% ethanol, the volume swelling rate of the lining is ≤ 3%, the mass change rate is ≤ 1.2%, and the resistance value fluctuates less than 5% after continuous friction for 100000 times, ensuring continuous static electricity discharge.

 

The reinforcement layer adopts a composite structure of "aramid fiber weaving+steel wire winding". Kevlar fiber (Kevlar 49) is cross woven at ± 55 ° to provide a burst pressure of ≥ 8MPa. The steel wire winding layer (diameter 0.25mm, winding density 90%) enhances the torsional performance, ensuring that the deformation of the hose under 3MPa hydraulic impact is controlled within 1.8%. The outer sheath is made of chloroprene rubber (CR) and nano zinc oxide composite material. By adding ultraviolet absorber (UV-531) and ozone inhibitor (445), the tensile strength retention rate after artificial accelerated aging test (xenon lamp irradiation for 1000 hours) is ≥ 85%, and the elongation at break retention rate is ≥ 70%, which extends the service life of traditional rubber by 4 times.

 

The joint design has passed API 16C and UL certification, using aluminum alloy forging material (6061-T6), surface hard anodizing treatment (thickness ≥ 25 μ m), and is matched with conductive rubber sealing ring and grounding copper braid (cross-sectional area ≥ 16mm ²) to achieve equipotential connection between the hose and the fuel dispenser. A test conducted at a certain gas station shows that the static potential difference of the joint is always less than 50V during continuous refueling operations, far below the 100V threshold required by GB 50156 standard, and the grounding resistance is ≤ 0.1 Ω, ensuring the explosion-proof safety of refueling operations.

 

2、 Full scene adaptation of gas stations: flexible conveying solution from fuel guns to oil tankers

1. High frequency bending and oil resistance challenge at the end of the fuel gun

Under frequent start stop and bending conditions of the fuel gun, the DN50 hose needs to balance flexibility and oil resistance. The surface of the hose lining is treated with a microporous structure (pore size 0.1-0.3 μ m), which increases the pressure loss by only 8% when the oil flow rate is increased from 3m/s to 5m/s, while suppressing the permeation of oil molecules. The matching anti-static joint is equipped with built-in spring contacts to ensure continuity of conductivity even when the hose is bent at an angle of 180 °. In the application of a gas station in Sinopec, this design extends the replacement cycle of fuel gun hoses from 6 months to 24 months, reducing annual maintenance costs by 75%.

 

2. Anti aging and weather resistance requirements of oil tank truck unloading link

In response to the ultraviolet radiation and temperature difference changes during oil tank truck unloading, a light stabilizer (HALS 770) and a thermal insulation coating (thermal conductivity ≤ 0.08W/m · K) are added to the outer layer of the hose to reduce the surface temperature by 15 ℃ compared to ordinary hoses under summer exposure. At the same time, the reinforced layer steel wire is treated with galvanized nickel alloy (no red rust after 1000 hours of salt spray test), which can resist high salt spray environments in coastal areas. In a long-term test at a certain oil depot in Qingdao, the hose showed no cracking on the outer layer and no hardening on the inner lining after continuous use for 3 years, still meeting the requirements of API 16C standard.

 

3. Quick connection and explosion-proof performance under emergency conditions

To cope with sudden leaks at gas stations, hoses are equipped with quick connect fittings (connection time ≤ 5 seconds) and double-layer explosion-proof structures. When the inner hose ruptures, the outer explosion-proof sleeve (Kevlar fiber reinforced) can withstand a pressure of 2MPa and is equipped with a pressure sensor (accuracy ± 0.01MPa). The data is uploaded in real-time to the gas station management system through a wireless transmission module. In an emergency drill at a gas station, the system provided a 30 minute advance warning of the risk of local wear and tear exceeding the limit, avoiding an oil leakage accident.

 

3、 Quality control and intelligent upgrade: full lifecycle digital management

1. Strict production testing system

The production of DN50 hoses follows the dual system standards of API Q1 and ISO 9001, and 20 testing processes are required from raw materials to finished products:

 

Raw material testing: Fluororubber Mooney viscosity (ML1)+ 10@121 The fluctuation range is ± 2 ℃, and the breaking strength of aramid fiber is ≥ 28cN/dtex;

Process monitoring: Real time recording of vulcanization temperature ± 0.5 ℃, pressure ± 0.02MPa, weaving angle deviation ≤± 0.5 °;

Finished product testing: burst pressure ≥ 15MPa (1.5 times the design pressure), pulse fatigue life ≥ 800000 times (pressure cycle 0-10MPa), low-temperature brittleness (no cracks at -40 ℃).

2. Digital traceability and predictive maintenance

Each hose is equipped with an RFID chip and QR code, storing over 400 data items such as production batches, inspection reports, installation locations, etc. In the practice of a gas station of PetroChina, the system increased inventory turnover by 55% and shortened the fault location time from an average of 48 hours to 2 hours. At the same time, the distributed fiber optic sensors embedded in the hose can monitor temperature (accuracy ± 0.3 ℃), pressure (accuracy ± 0.02MPa), and deformation (sensitivity 0.002mm), predict remaining life through machine learning algorithms, and improve maintenance plan accuracy by 65%.

 

3. Trends in Green and Intelligent Technologies

In the future, hose technology will evolve in the following directions:

 

Self repairing material: embedded with microcapsule repair agent, automatically filled when microcracks occur, extending service life;

Lightweight design: using carbon fiber reinforced composite materials, reducing weight by 20% without compromising strength;

Energy recovery: Integrating piezoelectric materials on the outer layer of the hose to convert fluid pressure energy into electrical energy, supplying power to IoT devices at gas stations.

4、 Industry Application Case: Practical Verification from Cities to Highways

City gas station: Shell's gas station in a certain city uses DN50 hoses to connect the fuel dispenser and the oil gun. When transporting 98 # gasoline, the lining has excellent oil resistance and anti-static performance. After continuous operation for 2 years, there is no carbon deposition on the inner wall, and the resistance value is stable at 10 ΩΩ, reducing static electricity risk by 80% compared to traditional products.

High speed service area: A gas station in a service area of the Beijing Hong Kong Macau Expressway uses this hose to cope with high-frequency refueling (5000 times per day). The aramid fiber reinforced structure is combined with explosion-proof joints to ensure that the hose does not break after continuous bending for 1 million times, reducing the failure rate by 90%.

Oil depots in extremely cold regions: A certain oil depot in Inner Mongolia tested the low-temperature performance of hoses in an environment of -35 ℃. The outer sheath's resistance to brittle cracking met the requirements, and the inner lining of the fluororubber did not harden, ensuring the safety of oil transportation in extremely cold weather.

conclusion

API standard DN50 hydraulic filling hose anti-static anti-aging flexible conveying pipe of gas station has built a technical system suitable for complex working conditions of gas station through material innovation, structural optimization and intelligent integration. From the high-frequency bending and oil resistance challenges at the end of the refueling gun, to the anti-aging and weather resistance requirements at the unloading link of the tank truck, and to the fast connection and explosion-proof performance under emergency conditions, its performance has verified the deep integration of API standards and domestic technologies. In the future, with the intelligent transformation of gas stations and the increasing demand for green operation, such products will play a more critical role in improving safety levels, reducing maintenance costs, and ensuring energy supply, promoting the fuel equipment industry to move towards efficiency, safety, and sustainability.