阅读说明：本技术 一种铁路钢轨接缝、火车轮毂探伤用超声波耦合剂及其制备方法 (Ultrasonic coupling agent for flaw detection of railway steel rail joint and train wheel hub and preparation method thereof ) 是由 刘俊宁 韩素平 周水清 白紫兰 于 2020-12-31 设计创作，主要内容包括：本发明提供一种铁路钢轨接缝、火车轮毂探伤用超声波耦合剂及其制备方法。本发明超声波耦合剂,包括如下质量百分比的原料组成：乙醇25～35％、乙二醇3～10％、水60～70％、羟乙基纤维素0.8～1.2％。本发明耦合剂透波性更稳定和良好,同时具有阻燃性、超耐低温性、25～35分钟自主挥发性,且不会对铁轨造成危害,成本较低,安全环保；粘度适中,与铁路钢轨、火车轮毂容易产生亲水性,易形成膜；并具有较好的应用前景。(The invention provides an ultrasonic coupling agent for flaw detection of railway steel rail joints and train wheel hubs and a preparation method thereof. The ultrasonic coupling agent comprises the following raw materials in percentage by mass: 25-35% of ethanol, 3-10% of ethylene glycol, 60-70% of water and 0.8-1.2% of hydroxyethyl cellulose. The couplant disclosed by the invention is more stable and good in wave permeability, has flame retardance, ultra-low temperature resistance and autonomous volatility for 25-35 minutes, does not cause damage to rails, is lower in cost, and is safe and environment-friendly; the viscosity is moderate, and the hydrophilic polyurethane emulsion is easy to generate hydrophilicity with railway rails and railway wheel hubs and is easy to form a film; and has better application prospect.)

1. The ultrasonic coupling agent for flaw detection of railway steel rail joints and railway wheel hubs is characterized by comprising the following raw materials in percentage by mass: 25-35% of ethanol, 3-10% of ethylene glycol, 60-70% of water and 0.8-1.2% of hydroxyethyl cellulose.

2. The ultrasonic couplant for flaw detection of railway steel rail joints and railway wheel hubs according to claim 1, wherein the ultrasonic couplant for flaw detection of railway steel rail joints and railway wheel hubs comprises the following raw materials in percentage by mass: 28-32% of ethanol, 3-8% of ethylene glycol, 62-68% of water and 0.8-1.0% of hydroxyethyl cellulose.

3. The ultrasonic couplant for flaw detection of railway steel rail joints and railway wheel hubs according to claim 2, wherein the ultrasonic couplant for flaw detection of railway steel rail joints and railway wheel hubs comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol, 64-64.2% of water and 0.8-1.0% of hydroxyethyl cellulose.

4. The method for preparing the ultrasonic couplant for flaw detection of the railway steel rail joints and the railway wheel hubs according to any one of claims 1-2 comprises the following steps: uniformly mixing ethanol, glycol and water, adding hydroxyethyl cellulose in batches, and stirring until the hydroxyethyl cellulose is completely dissolved to obtain the ultrasonic couplant for flaw detection of railway steel rail joints and train wheel hubs.

5. The method for preparing the ultrasonic couplant for flaw detection of the railway steel rail joint and the railway wheel hub according to claim 4, wherein the stirring speed is 1-3 r/s.

6. The method for preparing the ultrasonic couplant for flaw detection of the steel rail joints and the wheel hubs of the railway wheels according to claim 4, wherein the hydroxyethyl cellulose is added in 4 batches.

Technical Field

The invention relates to an ultrasonic coupling agent for flaw detection of railway steel rail joints and train wheel hubs and a preparation method thereof, belonging to the technical field of ultrasonic coupling agents.

Background

The most common method at present is ultrasonic flaw detection for flaw detection of railway steel rail joints and railway wheel hubs; the couplant used in the ultrasonic probe detection operation is mostly engine oil, and the engine oil used as the couplant has many defects: (1) the pollution is serious, and the engine oil can automatically flow to the railway line when the railway seam is subjected to flaw detection due to the fact that the engine oil is not easy to volatilize, so that great pollution is caused to the surrounding environment; (2) the method has the advantages that potential safety hazards are caused, flaw detection of the wheel hubs can be carried out indoors, fire hazards are caused easily due to inflammable and flammable engine oil, and during railway seam detection, the engine oil easily pollutes rails and causes potential hazards to train brakes; (3) the efficiency is low, when flaw detection is carried out on a rail joint and a hub of a train wheel, an operator needs to carry a wiping cloth or toilet paper for wiping machine oil, and the operation speed is influenced by wiping while detecting; (4) the price is high, and the engine oil for flaw detection is expensive; (5) the smell of the engine oil is large, and hidden troubles exist for the health of constructors.

In order to solve the problems of the engine oil, the development and research on the composite coupling agent have been carried out in the prior art. For example, chinese patent document CN108132307A discloses a steel rail flaw detection industrial coupling agent, which comprises the following components in parts by weight: 40-60 parts of ethylene glycol; 40-50 parts of water; 3-8 parts of glycerol; 1-2 parts of antirust agent, wherein the steel rail flaw detection industrial couplant also comprises trimethylolpropane, and the trimethylolpropane accounts for 0.5-3 wt% of the total weight of the steel rail flaw detection industrial couplant. The industrial couplant for steel rail flaw detection has excellent sound transmission effect, antirust and anticorrosive performance and low temperature resistance; but has the following disadvantages: (1) the viscosity of the coupling agent is too low, so that the coupling agent can easily flow down when a vertical joint of a steel rail is detected, and the detection is difficult to complete; (2) glycerol hardly volatilizes at normal temperature, and can be left for a long time after being coated on a rail, and the lubricating effect of the glycerol can cause potential safety hazards to train braking. For another example, chinese patent document CN108285555A discloses a steel rail welding seam ultrasonic flaw detection coupling agent and a preparation method thereof, wherein the coupling agent is composed of the following raw materials by mass: 30-50% of sodium carboxymethylcellulose, 5-25% of ethanol, 3-13% of glycerol, 0.5-8% of ethylparaben and the balance of distilled water. The coupling agent of the invention also has the disadvantages that: (1) the viscosity of the coupling agent is too low, so that the coupling agent can easily flow down when a vertical joint of a steel rail is detected, and the detection is difficult to complete; (2) glycerol hardly volatilizes at normal temperature, and can be left for a long time after being coated on a rail, and the lubricating effect of the glycerol can cause potential safety hazards to train braking.

Therefore, it is necessary to develop a special coupling agent for flaw detection of steel rail joints and train hubs to solve the hidden troubles and disadvantages.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an ultrasonic coupling agent for flaw detection of railway steel rail joints and railway wheel hubs and a preparation method thereof. The couplant disclosed by the invention is more stable and good in wave permeability, has flame retardance, ultra-low temperature resistance and autonomous volatility for 25-35 minutes, does not cause damage to rails, is lower in cost, and is safe and environment-friendly; the viscosity is moderate, and the hydrophilic polyurethane emulsion is easy to generate hydrophilicity with railway rails and railway wheel hubs and is easy to form a film; and has better application prospect.

The technical scheme of the invention is as follows:

an ultrasonic coupling agent for flaw detection of railway steel rail joints and railway wheel hubs comprises the following raw materials in percentage by mass: 25-35% of ethanol, 3-10% of ethylene glycol, 60-70% of water and 0.8-1.2% of hydroxyethyl cellulose.

According to the optimization of the invention, the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following raw materials in percentage by mass: 28-32% of ethanol, 3-8% of ethylene glycol, 62-68% of water and 0.8-1.0% of hydroxyethyl cellulose.

Preferably, the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol, 64-64.2% of water and 0.8-1.0% of hydroxyethyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: uniformly mixing ethanol, glycol and water, adding hydroxyethyl cellulose in batches, and stirring until the hydroxyethyl cellulose is completely dissolved to obtain the ultrasonic couplant for flaw detection of railway steel rail joints and train wheel hubs.

According to the invention, the stirring speed is preferably 1-3 rpm.

Preferably, according to the invention, the hydroxyethylcellulose is added in 4 portions.

The invention has the technical characteristics and beneficial effects that:

1. the hydroxyethyl cellulose has the function of enabling the couplant to have certain viscosity and hydrophilicity, and the hydroxyethyl cellulose solution has good rheological property, namely the viscosity is low when the couplant flows and the viscosity is high when the couplant is static, so that the obtained couplant can easily form a film on the surface of a rail and is not easy to roll off the rail. The ethanol and the glycol have the functions of lowering the freezing point of the coupling agent and enabling the coupling agent to work at ultralow temperature; meanwhile, the coupling agent has certain time of self-volatility. Moreover, the various components of the present invention do not act independently, but rather interact with each other, and the following effects of the present invention are achieved by the combined action; the raw material proportion and the raw material type of the invention are both specific, and the effect of the invention can be realized only by the raw materials with the specific proportion and the specific type.

2. The coupling agent disclosed by the invention has autonomous volatility of 25-35 minutes, is convenient for secondary test, does not influence secondary operation, reduces the cost, improves the working efficiency, and does not cause damage to rails; the components of the coupling agent do not relate to metal salt, and the obtained coupling agent does not corrode the rail; the couplant is mainly composed of water, has low organic matter content which is far lower than the proportion required by combustion, has good flame retardance, and avoids serious potential safety hazard caused by combustion due to the use of engine oil; as the testing of the hub is performed indoors, the couplant avoids the use of toxic methanol, and is safe and environment-friendly.

3. The coupling agent has ultra-low temperature resistance, can be prepared into coupling liquid which does not freeze at-20 ℃ to-40 ℃ according to the operating environment, and does not influence the use effect in severe cold time and areas in winter; and the wave permeability is more stable and good, and the requirements of standardized and standardized operation quality are met.

4. The coupling agent has moderate viscosity and is easy to generate hydrophilicity with rails; when the paint is used for coating the rails, the paint is easy to form films, is uniformly dispersed and easy to operate, reduces the phenomenon of detection errors, and can reduce the using quantity of unit working faces; has better application prospect.

5. The raw materials used in the invention are safe and environment-friendly; the preparation method is simple, the raw materials are cheap and easy to obtain, the stable mass production condition is realized, the use, the packaging and the transportation are convenient, the cost can be reduced, and obvious economic benefits can be obtained.

Detailed Description

The invention is further illustrated by the following specific examples, without limiting the scope of the invention thereto.

The raw materials used in the examples are commercially available unless otherwise specified; the methods used are conventional methods unless otherwise specified.

Example 1

An ultrasonic coupling agent for flaw detection of railway steel rail joints and railway wheel hubs comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol, 64.2% of water and 0.8% of hydroxyethyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: after ethanol, glycol and water are uniformly mixed, hydroxyethyl cellulose is added in 4 batches, and the mixture is stirred at the stirring speed of 2 r/s until the hydroxyethyl cellulose is completely dissolved, thus obtaining the ultrasonic coupling agent.

The low temperature resistance of the coupling agent obtained in the embodiment can reach-40 ℃.

Example 2

An ultrasonic coupling agent for flaw detection of railway steel rail joints and railway wheel hubs comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol, 64% of water and 1.0% of hydroxyethyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: after ethanol, glycol and water are uniformly mixed, hydroxyethyl cellulose is added in 4 batches, and the mixture is stirred at the stirring speed of 2 r/s until the hydroxyethyl cellulose is completely dissolved, thus obtaining the ultrasonic coupling agent.

The low temperature resistance of the coupling agent obtained in the embodiment can reach-40 ℃.

Example 3

An ultrasonic coupling agent for flaw detection of railway steel rail joints and railway wheel hubs comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol, 64.1% of water and 0.9% of hydroxyethyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: after ethanol, glycol and water are uniformly mixed, hydroxyethyl cellulose is added in 4 batches, and the mixture is stirred at the stirring speed of 2 r/s until the hydroxyethyl cellulose is completely dissolved, thus obtaining the ultrasonic coupling agent.

Comparative example 1

An ultrasonic coupling agent comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol and 65% of water.

The preparation method of the ultrasonic coupling agent comprises the following steps: and uniformly mixing ethanol, glycol and water to obtain the ultrasonic coupling agent.

Comparative example 2

An ultrasonic coupling agent comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol, 64.4% of water and 0.6% of hydroxyethyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: after ethanol, glycol and water are uniformly mixed, hydroxyethyl cellulose is added in 4 batches, and the mixture is stirred at the stirring speed of 2 r/s until the hydroxyethyl cellulose is completely dissolved, thus obtaining the ultrasonic coupling agent.

Comparative example 3

An ultrasonic coupling agent comprises the following raw materials in percentage by mass: 30% of ethanol, 69.2% of water and 0.8% of hydroxyethyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: after ethanol and water are uniformly mixed, adding hydroxyethyl cellulose in 4 batches, and stirring at a stirring speed of 2 r/s until the hydroxyethyl cellulose is completely dissolved to obtain the ultrasonic couplant.

Comparative example 4

An ultrasonic coupling agent comprises the following raw materials in percentage by mass: 5% of ethylene glycol, 94.2% of water and 0.8% of hydroxyethyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: after the ethylene glycol and the water are uniformly mixed, the hydroxyethyl cellulose is added in 4 batches, and the mixture is stirred at the stirring speed of 2 r/s until the hydroxyethyl cellulose is completely dissolved, so that the ultrasonic couplant is obtained.

The couplant obtained by the comparative example does not meet the requirement of low temperature resistance.

Comparative example 5

An ultrasonic coupling agent comprises the following raw materials in percentage by mass: 30% of ethanol, 5% of ethylene glycol, 64.2% of water and 0.8% of hydroxypropyl cellulose.

The preparation method of the ultrasonic coupling agent for flaw detection of the railway steel rail joint and the railway wheel hub comprises the following steps: uniformly mixing ethanol, glycol and water, adding hydroxypropyl cellulose in 4 batches, and stirring at a stirring speed of 2 r/s until the hydroxyethyl cellulose is completely dissolved to obtain the ultrasonic coupling agent.

Test examples

The coupling agent prepared in the examples and the comparative examples and 40W of engine oil are coated on the hub, and the volatilization time, viscosity (rotational viscosity method), film forming state, wave transmission state and flowing state of the coupling agent are tested, and the specific data are shown in the following table 1.

TABLE 1 test data sheet

Note: the test temperature is 25 ℃, and the relative humidity is 50%;

through experimental comparison, after the hydroxyethyl cellulose is added, the film forming state of the coupling agent is good, the coupling agent is not easy to flow on a hub, the comprehensive performance is greatly improved, and the requirements of railway use are completely met. The performance of the coupling agent prepared by the embodiment of the invention is better than that of a comparative example, which shows that the raw materials of the invention have synergistic effect, and the raw material proportion and the selection of the raw material types have specificity.