The working conditions of oilfield pumping pipeline industry have been harsh and prone to damage, leading to various problems in machine operation, affecting production efficiency and safety. Material selection needs to meet certain standards.

The main problems faced by oil and gas pipelines:

First: chemical corrosion, bacterial corrosion, and electrochemical corrosion during the use of oil and gas pipelines may cause product failure and destruction;

Second: As the depth of the oil and gas pipeline increases in the underground, the ambient temperature around the pipeline increases continuously, and the material needs to have high temperature resistance, otherwise the material will soften and fail.

Third: the oil and gas pipeline consists of several components from the inside to the outside. The penetration of corrosive substances can cause damage to the peripheral materials and test the chemical resistance and barrier properties of the materials.

1 Oil resistance: The inner layer of oil and gas pipelines is eroded by the transport fluid medium for a long time. According to the law of similar compatibility, ordinary olefin materials have poor oil resistance and severe swelling phenomenon.

2 H2S (hydrogen sulfide) tolerance: H2S is toxic and corrosive, which will cause damage to materials. It is a big safety hazard in oil and gas transportation.

3 Permeability resistance: The inner layer material can resist the corrosion of oil and gas liquids, and it is necessary to prevent liquid penetration and protect the peripheral pipeline from corrosion.

4 Bubble resistance: Under certain chemical medium conditions, when the external environment pressure changes rapidly, bubbles will appear, which will reduce the material permeability and mechanical strength.

At present, the commonly used materials for oil well liners are: HDPE, XPE, PEX, PA12, PVDF, PERT, PPS, PEEK, UHMW-PE.

Due to the low temperature of HDPE, XPE, PEX, PERT, UHMW-PE and PA12, it is only suitable for oil wells of 2000-3000 meters. Although PPS has excellent high temperature resistance and outstanding chemical resistance, the material is brittle and the bending performance is poor.

PEEK materials have superior overall performance but are expensive and not suitable for a wide range of applications. Therefore, the industry urgently needs a high temperature resistant 100 ° C -120 ° C polymer material that can be applied to oil fields above 4,000 meters.

In response to the practical problems existing in the above-mentioned oil well liners, NFD has developed and developed the special modified material Hepla® PTE X003 specially developed for oil well lining pipelines after 2 years of research and development.

NFD PTE plastics have a high temperature resistance up to 150 ° C and are excellent in chemical resistance, barrier properties, fuel resistance, abrasion resistance, impact resistance, high temperature resistance, bending properties and dimensional stability.

The following is a comparison of the basic properties of Hepla® PTE X003 with PA6 and PA66.

Dry test conditions: 50% relative humidity, 23 ° C, 24 hours. Wetting test conditions: 90% relative humidity, 23 ° C, 100 days.

The following is a comparison between PTE and common engineering plastics flexural modulus and heat distortion temperature (HDT).

The following is a comparison of the linear wear rate of PTE material with PA66 and POM materials with increasing speed.

Test conditions: load 1 MPa, run for one hour, ambient temperature 23 °C.

The following is a comparison of the linear wear rate of PTE/PA66, POM/PA66 materials with load.

Test conditions: 26.7 rpm, one hour of operation, and an ambient temperature of 135 °C.

The following is the comparison of tensile strength of PTE with PVDF, PA11 and HDPE at -30 °C, 23 °C and 120 °C.

The following is a comparison of the chemical resistance of PTE materials with other engineering plastics.

The + sign indicates resistance to resistance - the number indicates resistance

PTE tensile test strips were immersed in a mixed solvent (benzene 1%; toluene 7%; xylene 11%; cyclopentene 6%; cyclohexane 6%; C4-C5 17%; C6-C10 42%; C11 10 % )

After soaking for 130 days at 20 ° C, 40 ° C, 60 ° C, 80 ° C, and 120 ° C, the test results are as follows.

Fuel resistance test, test conditions 23 ° C, Fuel C + 15% methanol.

The PTE material is compared to the PA11 material methane (CH4) permeability test as follows, with an ambient relative humidity of 0%.

The following is a comparison of the carbon dioxide (CO2) permeability test of PTE, PA11, HDPE materials, and the relative humidity of the environment is 0%.

NFD actual working condition test:

1. The inner tube of the metal tube is PTE tube with a length of 5,000 meters. The test environment is seawater and floating matter environment. Test pass

2. 45% crude oil + 33% water + 25% acidic corrosive medium (hydrogen sulfide, carbon dioxide gas) + 80 ~ 120 ° C + pressure + test depth 4000 ~ 4500 meters.

Actual oil recovery test, no problems were found for 6 months.