1. The wear-resistant steel elbow is characterized by comprising an elbow body and a wear-resistant layer on the surface of the elbow body, wherein the wear-resistant layer is prepared from the following raw materials in parts by weight:

100 portions of fluorocarbon resin and 120 portions of fluorocarbon resin;

15-25 parts of epoxy resin;

8-12 parts of butyl acrylate;

2-6 parts of styrene;

11-36 parts of phosphate;

70-90 parts of a diluent;

7-12 parts of a silane coupling agent.

2. A wear-resistant steel elbow according to claim 1, characterized in that: also comprises 20 to 30 parts by weight of polypropylene glycol.

3. A wear-resistant steel elbow as claimed in claim 2, characterized in that: also comprises 30-40 parts of plant ash by weight.

4. A wear-resistant steel elbow according to claim 3, characterized in that: the plant ash is corncob plant ash.

5. A wear-resistant steel elbow according to claim 3, characterized in that: the fineness of the plant ash is 8000-10000 meshes.

6. A wear-resistant steel elbow according to claim 3, characterized in that: the diluent is a mixture of methyl isobutyl ketone, xylene and ethyl acetate, and the weight ratio of the methyl isobutyl ketone, the xylene and the ethyl acetate is (2-3): (2-3): (1-2).

7. A wear-resistant steel elbow according to claim 1, characterized in that: also comprises 6 to 10 weight portions of flatting agent.

8. A wear-resistant steel elbow according to claim 1, characterized in that: also comprises 15 to 20 weight portions of ultraviolet resistant agent.

Background

In a piping system, a bend is a pipe that changes the direction of a pipe. The elbow is made of cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, nonferrous metal, plastic, etc., wherein the alloy steel has an extremely wide application range due to its excellent mechanical strength.

The connection mode of the alloy steel elbow and the pipeline is generally direct welding, flange connection, hot melt connection, electric melting connection, threaded connection, socket connection and the like.

The stainless steel pipeline protection generally adopts an anticorrosive coating system, which comprises epoxy anticorrosive and antirust primer and fluorocarbon weather-resistant finish paint, and prolongs the service life of the pipeline through the physical barrier effect.

However, when the elbow is connected with the pipeline in a threaded connection mode, the joint of the elbow and the pipeline is rubbed, so that the coating at the joint of the elbow and the pipeline is abraded, and when the elbow is used in a marine or industrial atmospheric corrosion environment, the abraded part of the coating of the elbow is easily corroded, so that the problem of leakage of the transported substances in the pipeline is caused.

Disclosure of Invention

In order to improve the easy wearing and tearing of coating in elbow and pipeline threaded connection department, lead to the problem that the elbow was corroded, this application provides a wear-resisting steel elbow.

The application provides a wear-resisting steel elbow adopts following technical scheme:

the wear-resistant steel elbow is characterized by comprising an elbow body and a wear-resistant layer on the surface of the elbow body, wherein the wear-resistant layer is prepared from the following raw materials in parts by weight:

100 portions of fluorocarbon resin and 120 portions of fluorocarbon resin;

15-25 parts of epoxy resin;

8-12 parts of butyl acrylate;

2-6 parts of styrene;

11-36 parts of phosphate;

30-40 parts of talcum powder;

70-90 parts of a diluent;

7-12 parts of a silane coupling agent.

Through adopting above-mentioned technical scheme, adopt fluorocarbon resin as the major ingredient, fluorocarbon resin has better corrosion resisting property, makes the wearing layer can adapt to the multiple corrosive liquids of carrying in the pipeline, and the wearing layer keeps apart material and elbow body, makes the difficult quilt of elbow main part corrode. The epoxy resin has stronger adhesive property to the elbow body, so that the adhesive strength between the wear-resistant layer and the elbow body is higher.

Butyl acrylate, styrene react with fluorocarbon resin and epoxy resin to obtain a styrene-acrylic-fluorocarbon-epoxy graft copolymer, and the styrene-acrylic-fluorocarbon-epoxy graft copolymer is grafted with phosphate to obtain a modified styrene-acrylic-fluorocarbon-epoxy graft copolymer, wherein the modified styrene-acrylic-fluorocarbon-epoxy graft copolymer has high internal crosslinking density and a complex crosslinking structure, so that the wear-resistant layer is more compact, the wear-resistant layer is not easy to scratch off when the wear-resistant layer is worn, and the elbow body is not easy to expose outside, thereby preventing the elbow body from being corroded.

The diluent is used for diluting each component, and the silane coupling agent is used for supporting the subsequent reaction.

Optionally, the polypropylene glycol is added in an amount of 20-30 parts by weight. .

By adopting the technical scheme, the polypropylene glycol and the modified styrene-acrylic-fluorocarbon-epoxy graft copolymer are further grafted, so that the compactness of the wear-resistant layer is further improved, and the wear resistance is improved. The wear-resistant layer has high strength due to a large amount of rigid ring substances (benzene rings) in the modified styrene-acrylic-fluorocarbon-epoxy graft copolymer, and cracks easily appear in the wear-resistant layer when the elbow is collided and extruded. And the elbow can be extruded inevitably when threaded connection, leads to the wearing layer easy crackle to appear, makes corrosive liquid immerse from the crackle easily to with elbow body direct contact, lead to the elbow body to be corroded.

Through the flexible polyether chain segment that introduces in the propylene glycol, make wearing layer mechanism change in solidification crosslinked network, form the heterogeneous network structure that is fine and close but has better strain capacity, thereby improve the toughness of wearing layer, improve the counter stress of wearing layer when receiving external force, make the wearing layer difficult appearance crackle when threaded connection on the one hand, make the elbow body difficult for exposing, on the other hand makes the wearing layer of elbow threaded connection department can further laminate the screw thread of pipeline after certain deformation, make the junction sealing performance of pipeline and elbow better, effectively prevent the gas leakage of carrying in the pipeline.

Optionally, the plant ash also comprises 30-40 parts by weight of plant ash.

Through the technical scheme, the plant ash is the ash generated after the plant burns, and is low in cost and easy to obtain. Because of its inside contains a large amount of active ingredient, it can add unnecessary active hydroxyl group in the back wearing layer with polypropylene glycol, make hydrophilic group quantity reduce in the wearing layer, thereby reduce the infiltration ability of water to the wearing layer, and plant ash has certain volume expansion after meeting water, after the wearing layer is damaged, the damaged border department of wearing layer is sealed up to the plant ash ability of volume expansion, make water be difficult to dip into between elbow body and the wearing layer from the border, thereby guarantee the bonding fastness of elbow body and wearing layer.

When the elbow body is corroded by the substances conveyed in the pipeline to a certain degree, the plugging of the plant ash slows down the corrosive substances from immersing between the elbow body and the wear-resistant layer, so that the corrosion speed of the elbow body is slowed down, and the durability of the elbow is better.

Optionally, the plant ash is corncob plant ash.

Through above-mentioned technical scheme, corncob plant ash granule is fine and smooth, even, and the water swelling degree is less, prevents that the volume is too big to strut wearing layer and elbow body separation after the water swelling to influence the cohesive strength between wearing layer and the elbow body.

Optionally, the fineness of the plant ash is 8000-10000 meshes.

Through the technical scheme, the wear-resistant layer is fine and smooth in hand feeling under the cover fineness, and the volume of the plant ash is moderate after water absorption and expansion, so that the bonding strength between the wear-resistant layer and the elbow body is not easily influenced.

Optionally, the diluent is a mixture of methyl isobutyl ketone, xylene and ethyl acetate, and the weight ratio of the methyl isobutyl ketone, the xylene and the ethyl acetate is (2-3): (2-3): (1-2).

Through the technical scheme, the diluent has good compatibility with each component, and is not easy to precipitate. And the anhydrous diluent is adopted, so that the phenomenon that the plant ash is coated when the plant ash is in expansion, a large number of air holes are formed in the wear-resistant layer after water is dried, the structural tightness of the wear-resistant layer is reduced, and the wear resistance of the wear-resistant layer is influenced.

Optionally, the paint also comprises 6-10 parts of a leveling agent by weight.

Through the technical scheme, the flatting agent improves the permeability of the coating liquid, can reduce the possibility of generating spots and scars during brushing, increases the coverage, ensures that the formed film is uniform and natural, and ensures that the wear-resistant layer is uniformly coated.

Optionally, the UV-resistant agent also comprises 15-20 parts by weight of UV-resistant agent.

Through the technical scheme, the wear-resistant layer is not easy to decompose under ultraviolet rays, namely under the irradiation of sunlight, through adding the ultraviolet resistant agent, the wear-resistant layer is not easy to decompose, and the wear-resistant layer has better ultraviolet resistance, so that the durability of the wear-resistant layer is improved.

In summary, the present application has the following beneficial effects:

1. because the modified styrene-acrylic-fluorocarbon-epoxy graft copolymer is obtained by adopting the phosphate ester grafted fluorocarbon resin, the epoxy resin, the butyl acrylate and the styrene, the wear-resistant layer is not easy to scratch off, thereby preventing the elbow body from being corroded.

2. The polypropylene glycol and the modified styrene-fluorocarbon-epoxy graft copolymer are further grafted, so that the wear resistance and toughness of the wear-resistant layer are improved.

3. By adding plant ash, the water-resistant adhesion of the wear-resistant layer is improved.

Detailed Description

The present application will be described in further detail with reference to examples.

Name of raw materials	Species or origin
		Fluorocarbon resin	Sold by Hubei Xingheng Hengye science and technology Limited
Epoxy resin	Mooney brand, bisphenol A type epoxy resin E-44
		Phosphoric acid esters	Sold by Wuhan Jiangxin Yu Biotechnology Limited
Silane coupling agent	Silane coupling agent KH-602
		Polypropylene glycol	Polypropylene glycol (PPG-1000)
Plant ash	Corncob is burnt, the fineness is 5000 meshes, 8000 meshes and 10000 meshes
		Leveling agent	TEGO Di high leveling agent (TEGO 410)
Anti-ultraviolet agent	Bensvin (326) as a Pasteur UV absorber

Preparation example of intermediate

Preparation example 1

Preparation of the diluent:

weighing 30 parts of methyl isobutyl ketone, 30 parts of dimethylbenzene and 20 parts of ethyl acetate according to parts by weight, and uniformly stirring and mixing to prepare the diluent.

Examples

Example 1

The wear-resistant steel elbow comprises an elbow body and a wear-resistant layer on the surface of the elbow body, wherein the wear-resistant layer is made of 304 stainless steel materials and comprises the following raw materials in parts by weight:

100 parts of fluorocarbon resin;

15 parts of epoxy resin;

8 parts of butyl acrylate;

2 parts of styrene;

11 parts of phosphate;

70 parts of the diluent prepared in preparation example 1;

7 parts of a silane coupling agent.

The preparation method of the wear-resistant steel elbow comprises the following steps:

s1, weighing fluorocarbon resin, epoxy resin and the diluent prepared in preparation example 1 according to the weight parts required by the formula, adding the mixture into a container provided with a condensing tube and a stirrer, stirring and heating the mixture to 120 ℃ until the fluorocarbon resin and the epoxy resin are completely dissolved to obtain a base solution;

s2, weighing butyl acrylate, styrene and phosphate according to the weight parts required by the formula, and uniformly stirring and mixing to obtain a mixed solution;

s3, dropwise adding the mixed solution into the base solution at a speed of 4ml/min, and stirring for reacting for 4 hours after dropwise adding to obtain a reaction product;

s4, adding a silane coupling agent into the reaction product to obtain a mixed coating;

s5, coating the mixed paint on the elbow body, baking for 1h at 100 ℃ and baking for 1h at 160 ℃ to form a wear-resistant layer with the thickness of 1mm, and thus obtaining the wear-resistant steel elbow.

Example 2

The wear-resistant steel elbow comprises an elbow body and a wear-resistant layer on the surface of the elbow body, wherein the wear-resistant layer is made of 304 stainless steel materials and comprises the following raw materials in parts by weight:

120 parts of fluorocarbon resin;

25 parts of epoxy resin;

12 parts of butyl acrylate;

6 parts of styrene;

36 parts of phosphate;

90 parts of the diluent prepared in preparation example 1;

12 parts of a silane coupling agent.

The preparation method of the wear-resistant steel elbow comprises the following steps:

s1, weighing fluorocarbon resin, epoxy resin and the diluent prepared in preparation example 1 according to the weight parts required by the formula, adding the mixture into a container provided with a condensing tube and a stirrer, stirring and heating the mixture to 120 ℃ until the fluorocarbon resin and the epoxy resin are completely dissolved to obtain a base solution;

s2, weighing butyl acrylate, styrene and phosphate according to the weight parts required by the formula, and uniformly stirring and mixing to obtain a mixed solution;

s3, dropwise adding the mixed solution into the base solution at a speed of 4ml/min, and stirring for reacting for 4 hours after dropwise adding to obtain a reaction product;

s4, adding a silane coupling agent into the reaction product to obtain a mixed coating;

s5, coating the mixed paint on the elbow body, baking for 1h at 100 ℃ and baking for 1h at 160 ℃ to form a wear-resistant layer with the thickness of 1mm, and thus obtaining the wear-resistant steel elbow.

Example 3

The wear-resistant steel elbow comprises an elbow body and a wear-resistant layer on the surface of the elbow body, wherein the wear-resistant layer is made of 304 stainless steel materials and comprises the following raw materials in parts by weight:

110 parts of fluorocarbon resin;

20 parts of epoxy resin;

10 parts of butyl acrylate;

5 parts of styrene;

20 parts of phosphate;

80 parts of the diluent prepared in preparation example 1;

and 10 parts of a silane coupling agent.

The preparation method of the wear-resistant steel elbow comprises the following steps:

s1, weighing fluorocarbon resin, epoxy resin and the diluent prepared in preparation example 1 according to the weight parts required by the formula, adding the mixture into a container provided with a condensing tube and a stirrer, stirring and heating the mixture to 120 ℃ until the fluorocarbon resin and the epoxy resin are completely dissolved to obtain a base solution;

s2, weighing butyl acrylate, styrene and phosphate according to the weight parts required by the formula, and uniformly stirring and mixing to obtain a mixed solution;

s3, dropwise adding the mixed solution into the base solution at a speed of 4ml/min, and stirring for reacting for 4 hours after dropwise adding to obtain a reaction product;

s4, adding a silane coupling agent into the reaction product to obtain a mixed coating;

s5, coating the mixed paint on the elbow body, baking for 1h at 100 ℃ and baking for 1h at 160 ℃ to form a wear-resistant layer with the thickness of 1mm, and thus obtaining the wear-resistant steel elbow.

Example 4

The difference from example 3 is that 26 parts by weight of polypropylene glycol was further added in the step of S2.

Example 5

The difference from example 4 is that 35 parts by weight of corncob ash having a fineness of 8000 meshes was added to the reaction product obtained in the step of S3, and the reaction was continued with stirring.

Example 6

The difference from example 4 is that 35 parts by weight of corncob ash having a fineness of 10000 meshes was added to the reaction product obtained in the step of S3.

Example 7

The difference from example 4 is that 35 parts by weight of corncob ash having a fineness of 5000 mesh was added to the reaction product obtained in the step of S3.

Example 8

The difference from example 4 is that 35 parts by weight of straw plant ash with 8000 meshes of fineness is added to the reaction product obtained in the step of S3.

Example 9

The difference from example 5 is that 8 parts by weight of a leveling agent and 17 parts by weight of an ultraviolet screening agent were further added in step S4.

Comparative example

Comparative example 1

The difference from example 3 is that no phosphate is added.

Comparative example 2

The difference from example 3 is that no butyl acrylate is added.

Comparative example 3

The difference from example 3 is that no styrene is added.

Comparative example 4

The difference from example 3 is that no epoxy resin is added.

Performance test

The mixed paint prepared in examples and comparative examples was applied to a 304 stainless steel plate and baked at 100 ℃ for 1 hour and 160 ℃ for 1 hour to form a coating layer having a thickness of 1mm to obtain a sample piece, and the test was conducted on the sample piece as follows.

And (3) detection of wear resistance: the test pieces were tested by reference to GB-T1768-.

And (3) detection of toughness: the toughness of the test pieces was measured with reference to GB/T1731-1993 "paint flexibility determination" and reported in Table 2.

Detection of water adhesion resistance: cutting a coating on a sample piece according to GB/T9286-1998 grid test for paint films of colored paint and varnish, placing the cut sample piece in deionized water for soaking for 30 days, taking out and airing, detecting the adhesion grade of the paint film after soaking in water according to GB/T9286-1998 test method, and recording detailed results in Table 2.

TABLE 1

	100 turns	200 turn	300 turns	400 turn	500 turn
						Example 1	-	-	-	Rust formation
Example 2	-	-	-	Rust formation
						Example 3	-	-	-	Rust formation
Example 4	-	-	-	-	-
						Example 5	-	-	-	-	-
Example 6	-	-	-	-	-
						Example 7	-	-	-		Rust formation
Example 8	-	-	-		Rust formation
						Example 9	-	-	-	-	-
Comparative example 1	-	Rust formation	-	-	-
						Comparative example 2	-	Rust formation	-	-	-
Comparative example 3	-	Rust formation	-	-	-
						Comparative example 4	-	Rust formation	-	-	-

TABLE 2

	Flexibility mm	Paint film adhesion rating
			Example 1	3	4
Example 2	3	4
			Example 3	3	4
Example 4	1	3
			Example 5	1	1
Example 6	1	1
			Example 7	2	2
Example 8	2	2
			Example 9	1	1
Comparative example 1	3	5
			Comparative example 2	3	4
Comparative example 3	3	4
			Comparative example 4	2	5

Combining examples 1-3 and 4 with tables 1 and 2, it can be seen that the addition of polypropylene glycol significantly improves the toughness of the coating, and the abrasion resistance is improved to some extent, and the water adhesion resistance of the mixed coating is enhanced. The reason for this is that the graft introduction of the flexible polyether segments increases the toughness of the coating after the addition of polypropylene glycol. In general, the wear resistance of the coating is reduced after the flexibility is enhanced, but the internal structure of the coating is not easily damaged by adding polypropylene glycol to make the structure of the coating more compact and complex, so that the toughness of the coating is enhanced and the wear resistance is also enhanced. The water-resistant adhesion is enhanced because the internal structure of the coating is compact and water is not easy to permeate, so that the adhesion capability of the sample piece is still good after the sample piece is soaked in deionized water.

Combining example 4 with example 5 and example 6 with tables 1 and 2, it can be seen that the addition of corncob ash did not change the abrasion resistance of the coating significantly, but significantly improved the water adhesion resistance of the coating. The corncob plant ash neutralizes redundant active hydroxyl groups in the coating, so that the number of hydrophilic groups in the coating is reduced, and the permeability of water to the coating is reduced; and at the scratch, the corncob plant ash particles absorb water and swell, and the scratch boundary is blocked to prevent water from permeating, so that the water-resistant adhesion performance of the coating is obviously improved.

As can be seen by combining examples 5-8 and tables 1 and 2, the coating has good water adhesion resistance and good wear resistance when the corncob ash has the fineness of 8000-10000 meshes. When the fineness of the corncob plant ash is larger, large particles of the corncob plant ash are filled in the coating, the internal structure of the coating is influenced, the structure is loose, and the corncob plant ash has small hardness and density, so that the wear resistance of the coating is reduced. The straw plant ash has small activity, is difficult to completely neutralize active hydroxyl in the coating, and causes poor water penetration resistance, and compared with the corncob plant ash, the straw plant ash has large particle density difference, and causes uneven coating, thereby affecting the wear resistance, water adhesion resistance and flexibility of the coating.

Combining examples 5 and 10 with tables 1 and 2, it can be seen that the addition of the leveling agent and the uv-resistant agent does not change much the abrasion resistance, the water adhesion resistance and the flexibility of the coating, and can improve the coating uniformity and the uv resistance of the mixed coating.

Combining example 3 and comparative example 1 with tables 1 and 2, it can be seen that the phosphate is not added, so that the complexity of the coating structure is reduced, the structural compactness is reduced, the coating structure is easily damaged, and the wear resistance is reduced. The phosphate ester also reduces the water-resistant adhesion grade of the coating, and the coating forms a structure which does not react with water after grafting modification of the phosphate ester, so that substances in the coating are not easily dissolved by water after the coating is soaked in water, and the coating has better stability and compactness, so that the adhesion grade of the coating is not easily influenced by water.

When example 3 and comparative example 2 are combined with tables 1 and 2, it can be seen that the product structure is loose and the wear resistance and the water adhesion resistance are reduced without adding butyl acrylate or styrene, but the toughness is not changed much.

When example 3 and comparative example 4 are combined and tables 1 and 2 are combined, it can be seen that the toughness of the coating is improved but the auxiliary adhesion of the coating is reduced without the epoxy resin.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.