Introduction of epoxy FRP
Epoxy FRP mainly consists of modified solvent-free epoxy binder and glass fiber. The modified solvent-free epoxy binder is a two-component reactive material. The A component is composed of modified epoxy resin, various auxiliaries and high strength wear-resistant fillers. B is composed of heat-resistant, Hygrothermal and efficient imported curing agents. The modified solvent-free epoxy binder has good mechanical properties such as high wear resistance and scratch resistance. The epoxy FRP made of glass fiber is suitable for the outer sheath of directional drilling crossing pipeline.
Material properties are as follows:
1. glass fiber cloth should be selected with JC/T170 standard of alkali free glass cloth, both sides of the edge, no wax, the performance should meet the requirements of Table 1;
Table 1 technical index of glass cloth
Unit area quality
Less than 0.30
Alkali metal oxide content
Less than 0.8
combustible matter content
Less than 0.20
One hundred and ninety
One hundred and eighty
Root / mouth
16 + 1
12 + 1
2. the properties of epoxy resin and curing agent are shown in Table 2;
Table 2 technical index of epoxy resin
More than 95
1.40 to 1.53
1.02 to 1.05
More than 15
Less than 2
Less than 8
Anti 1 degree bending A
No crack and no leak point.
SY/T 0315-2005 appendix E
Impact resistance A
More than 8
SY/T 0315-2005 appendix F
Shao's D hardness
More than 80
A The coating thickness is 500 m
3. the performance of epoxy FRP protective layer is shown in Table 3.
Table 3 technical index of epoxy glass fiber reinforced plastic protection layer A
More than 30
Sand box test (100 times)
Edge without edge
Scratch resistance (50kg)
Less than 500
L/ mu m
More than 3
SY/T0315-2005 appendix J
Anti 1 degree bending
SY/T 0315-2005 appendix E
Bonding strength of PE C
More than 3.5
A The thickness of the coating is 1200 m (two cloth five oil).
B The thickness of the polyethylene sheet with a thickness of 4 + 0.1mm should be roughened and flame polarized on the surface of the PE test piece for the epoxy glass reinforced plastics with a thickness of 1200 m.
C The epoxy FRP is coated on a tube specimen with 3PE anticorrosive coating. After curing, it is tested according to appendix A. The surface of 3PE anticorrosive coating should be roughened and flame polarized.
Construction process and process of epoxy FRP outer sheath:
The specific operation is as follows:
The epoxy glass fiber reinforced plastic (FRP) is used in the field or factory prefabrication way to finish the operation procedure of the single pipe coating and the pipe welding after the completion of the welding, so as to complete the overall coating of the epoxy glass fiber reinforced plastic outer sheath through the pipeline.
The construction technology of epoxy FRP is two cloth and five oil, and the minimum thickness requirement is 1200um.
Two cloth five oil is epoxy resin (dry) + epoxy resin + glass cloth + epoxy resin + glass cloth + epoxy resin (dry) + epoxy resin.
4.1 PE surface treatment
The key point in the construction process of epoxy FRP is how to improve the bonding strength and shear strength between FRP coating and PE, so as to prevent the coating from falling off during the crossing process. Therefore, the surface of the construction PE should be clean, dirty and pollution-free.
4.2 construction conditions
The construction temperature of epoxy FRP is no less than 20 C (when temperature is too low) and relative humidity is not more than 80%.
4.3 epoxy FRP is coated with single pipe on the spot, and then the coating is carried out after the pipeline is welded, so as to complete the overall coating of the epoxy glass fiber reinforced plastic outer sheath through the pipeline.
A, tube surface treatment
The surface of the anticorrosive coating should be pre treated before painting, ensuring that it is intact and clean. The surface dehumidification of the anticorrosive coating is made by flame drying. The surface temperature should also meet the requirements of napping treatment (but should not exceed 110 degrees C), and the steel brush is used to cross coat the anticorrosive coating. The depth control is suitable for 0.4~0.5mm.
B, coated modified solvent free epoxy coating + hand wound glass cloth
The A and B components of the modified solventless epoxy coatings were mixed and proportionally mixed to uniform color. The rolling brush is then rolled evenly in the tube body. After the epoxy resin adhesive reaches the surface dry, the glass fiber cloth is wound to make the epoxy resin paint soaked through the glass fiber cloth. Manual winding of glass fiber cloth is as follows: after the epoxy resin adhesive is dried, spiral winding is installed and glass fiber cloth is installed. When installing, one end of glass fiber cloth will be stretched and stretched tightly. First, the ends will be overlapped in the brush area, spiral wound and circumferential rolling brush to ensure that the glass fiber cloth is completely wetted by epoxy resin adhesive, and there is no white hollowing phenomenon. The bottom has no flow hanging. According to the design technology of epoxy glass fiber reinforced plastic two cloth and five oil, repeat two winding glass cloth.
C, surface modified solventless epoxy resin coating.
After winding the glass fiber cloth, a layer of epoxy coating is applied on the surface of the glass fiber cloth to improve the abrasion resistance and scratch resistance of the epoxy FRP.
D, epoxy FRP construction as a whole.
After the coating process of two cloth and five oil for epoxy FRP is finished, the modified solvent-free epoxy coatings need to be solidified at a certain time. During the curing process, the bottom of the tube should be treated to ensure that the bottom is free from flow, and the whole shape is smooth, without hollowing and no whiteness.
4.4 points for attention in construction
(1) when the field temperature is low, the A component can be heated before FRP, but the heating temperature should not exceed 30 C (the upper limit of storage temperature). After mixing A and B components, electric tools are applied to the uniform color.
2. When the glass fiber reinforced plastic is coated, it is easy to generate flow hanging at six points due to the gravity causes. Attention should be paid to the coating when it is applied, and roller brushing treatment should be carried out in time to avoid dropping effect on the coating.
3. When glass fiber cloth is twisted, it should be stretched tightly. Strictly control the blank holder and lap width according to the technical documents, ensure that the overlap position of the two layers of glass cloth is stagger and avoid excessive local thickness.
4. During the process of coating and curing, FRP should strictly follow the requirements of engineering documents and product manuals. When the site temperature is low, the constructor should take necessary measures to ensure that the temperature of the FRP coating and curing part is above 20 C, so as to ensure the coating performance.