Formula of pouring type polyurethane material and construction process of pouring type polyurethane material in maintenance of conveying belt

Abstract

The invention relates to a formula of a pouring polyurethane material and a construction process of the pouring polyurethane material in maintenance of a conveying belt. The pouring type polyurethane material comprises the following components in parts by weight: 100 parts of a component A; 8-20 parts of a component B; 5-25 parts of a component C; 0.5 to 10 parts of a component D; 102 to 106 parts of a component E; the component C is a flame retardant, namely expanded graphite powder; and the component D is an antistatic liquid. The invention discloses a construction process of a pouring type polyurethane material in maintenance of a conveying belt. The construction process comprises the following steps: 1, polishing a damaged part, which needs to be repaired, of the conveying belt; 2, brushing the component E; 3, mixing the component A, the component B, the component C and the component D together; 4, pouring and leveling or strickling the stirred mixture; and 5, surface curing can be achieved within fifteen minutes, and requirements can be met within sixty minutes. The invention has the following advantages: the curing agent meets the requirements of MT / T113-1995 Regulation, can be formed by one-time pouring, and can meet the requirements of various on-site damage maintenance of the coal mine conveyor belt on curing speed, physical properties and adhesion.

Description

Technical Field

[0001] The present invention relates to the technical field, and particularly to a formula of a casting polyurethane material and a construction process thereof in belt repair. Background Art

[0002] The rubber conveyor belt is a key device for transporting materials from underground to aboveground in major coal mines. Due to the special mining environment of coal mining enterprises, the conveyor belt faces a large number of various damage problems, such as edge cracking, edge restoration, longitudinal tearing, strip tearing, holes, surface rubber peeling, wear and other various damage problems. If not repaired immediately, it is easy to cause the enterprise's transportation system to stop, bringing huge economic losses to the enterprise.

[0003] There are a wide variety of repair products on the market. Due to the particularity of coal mining enterprises, the repair products used must meet the requirements of MT / T113-1995 "General Test Methods and Determination Rules for Flame Retardancy and Antistatic Property of Polymer Products Used in Coal Mines" (hereinafter referred to as MT / T113-1995 "Rules"). Existing products either have neither flame retardancy nor antistatic property, or only have flame retardancy without antistatic property, and there is no product that fully meets the requirements of MT / T113-1995 "Rules".

[0004] The existing technical solutions for repairing various types of damage are as follows: 1. The traditional vulcanization repair process has the disadvantages of low efficiency, high labor intensity, and the need for a large number of personnel. Due to the particularity of coal mine enterprise production, the daily shutdown maintenance time is very short, averaging between 2 and 4 hours, which cannot meet the usage requirements; 2. The traditional cold bonding repair strip process, such as the cold bonding process of rubber repair strips, is a product commonly existing in the current market, with a wide variety of product brands. Its disadvantages are low repair quality, few problems solved, and unsatisfactory effects; the thickness of the cold bonding repair strip is generally 3.5 - 6.5 millimeters. For surface damage repair, the existing rubber surface needs to be polished to the thickness of the cold bonding repair strip, which is a kind of damage to the rubber surface of the tape. If cold bonding is done for the second time, the polished area needs to be expanded, which is also a damage to the tape structure and the polishing time is long; the cold bonding repair strip is relatively thick and hard, and has a small bonding area with the tape surface. The cold bonding process belongs to the wet bonding method, and there are volatile gases inside the bond, resulting in a bridging phenomenon. Therefore, the repair quality of the cold bonding process for solving damage problems is not ideal; the chemical reaction of the cold bonding process requires a long curing time and cannot meet the requirements of coal mine enterprises for immediate repair and use; the cold bonding process has high environmental requirements and is sensitive to humidity. Coal enterprises all produce and work in a humid environment; in addition, cold bonding is basically impossible to construct and use below 0°C; the cold bonding repair strip cannot be used alone to repair damage problems and needs to be repaired in cooperation with a repair adhesive, and the process flow is relatively cumbersome; 3. Traditional repair adhesive products mostly have a long curing time, low physical properties, and low initial strength. Due to the particularity of coal mine production, the maintenance time is relatively short. Before the materials are completely cured after repair, the machine starts production, resulting in low overall repair quality, few problems solved, and unsatisfactory effects; it is almost used for the wear repair of the tape surface and the repair of non - stressed scratches and holes, but cannot solve the repair of damage problems such as longitudinal tearing, edge restoration, and edge cracking that require higher bonding strength and physical strength of materials; 4. The polyurethane repair strip product is a new product in the past 10 years. Its disadvantages are that the material needs to be used in cooperation with special tools, and all the tools are conventional 220V non - explosion - proof tools. The process is cumbersome, and the maintenance personnel require relatively high professionalism. Its tools have relatively serious safety hazards. Most of its products are used in non - coal mines and on the ground, and are rarely adopted by large - scale regular coal mine enterprises; 5. The thermosetting polyurethane particles and polyurethane powder products are new products in the past 10 years. Its disadvantages are that the material needs to be used in cooperation with special tools, and all the tools are conventional 220V non - explosion - proof tools. The process is cumbersome, and the maintenance personnel require relatively high professionalism. Its tools have relatively serious safety hazards. Most of its products are used in non - coal mines and on the ground, and are rarely adopted by large - scale regular coal mine enterprises; 6. Polyurea spraying. Its disadvantages are that the material needs to be used in cooperation with a conventional non - explosion - proof spraying machine. Its products are mainly used in non - coal mines and on the ground. The problem it repairs is single - large - area wear repair, and other damage problems on the tape surface cannot be repaired. It is rarely used for underground tape repair.

[0005] Therefore, a casting polyurethane material formula and its construction process in conveyor belt maintenance are provided to solve the above problems. Summary of the Invention

[0006] To make up for the above deficiencies, the present invention provides a casting-type polyurethane material formulation and its construction process in conveyor belt repair.

[0007] The casting-type polyurethane material formulation includes:

[0008] 100 parts of Component A;

[0009] 8 - 20 parts of Component B; adjusted according to the reaction rate;

[0010] 5 - 25 parts of Component C; adjusted according to the flame retardant requirement level;

[0011] 0.5 - 10 parts of Component D; adjusted according to the antistatic requirement level;

[0012] 102 - 106 parts of Component E;

[0013] Component A is a masterbatch, that is, a terminal NCO polyurethane prepolymer formed by the reaction of macromolecular polyols and isocyanates (such as TDI, MDI, etc.);

[0014] Component B is a curing agent, that is, an aromatic diamine compound;

[0015] Component C is a flame retardant, that is, expandable graphite powder;

[0016] Component D is an antistatic liquid;

[0017] Component E is an interfacial agent.

[0018] Preferably, Component A should be a masterbatch with a viscosity below 5000 mpas at 25°C to ensure good fluidity and enable one-time forming for casting and repairing damaged parts;

[0019] Preferably, Component B is 3,5-dimethylthio toluene diamine or 3,3'-diethyl-4,4'-diamino diphenyl methane;

[0020] Preferably, the expandable graphite of Component C has a mesh number range of 30 - 300 meshes;

[0021] Preferably, Component D is dioxy-ester quaternary ammonium salt;

[0022] Preferably, Component E is dissolved trichloroisocyanuric acid.

[0023] The construction process of the casting-type polyurethane material in conveyor belt repair includes the following steps:

[0024] Step 1: Use a tungsten carbide grinding disc or a wire wheel to grind the damaged part of the conveyor belt that needs to be repaired, exposing a clean surface;

[0025] Step 2: Apply Component E to the part that needs to be repaired.

[0026] Step 3: Mix Component A, Component B, Component C, and Component D together and stir evenly.

[0027] Step 4: Quickly pour the mixture stirred in Step 3 onto the conveyor belt that needs to be repaired, and let it level naturally or quickly level it with a squeegee.

[0028] Step 5: The casting in Step 4 can reach surface curing within fifteen minutes and meet the requirements of the mine for starting the machine within sixty minutes.

[0029] Preferably, in Step 3, when mixing, Component D can be first added to Component B.

[0030] Preferably, in Step 3, when mixing, Component D can be first added to Component A.

[0031] Preferably, in Step 3, when mixing, Component C can be first added to Component B.

[0032] Preferably, in Step 3, when mixing, Component C can be first added to Component A.

[0033] Preferably, in Step 3, when mixing, Component C and Component D can be first added to Component B.

[0034] Preferably, in Step 3, when mixing, Component C and Component D can be first added to Component A.

[0035] The present invention has the following beneficial effects:

[0036] The present invention relates to a casting-type polyurethane material formula and its construction process in the repair of conveyor belt breakage, and has the following advantages:

[0037] 1. The casting-type polyurethane material meets the requirements of MT / T113-1995 "Rules" and can ensure the quality of the product in the repair of various conveyor belt breakages.

[0038] 2. The casting-type polyurethane material can be cast in one piece.

[0039] 3. The construction process of the casting-type polyurethane material in the repair of conveyor belt breakage improves the repair speed, does not require special tools, has low labor intensity, simple process, and high repair quality.

[0040] 4. The casting-type polyurethane material, mainly expandable graphite, has both excellent flame retardant effect, good electrical conductivity and liquid-phase adsorption lipophilicity. Due to the synergistic principle of the two substances, the usage amount of the antistatic agent is reduced, and problems such as the precipitation of oily substances are avoided, thus preventing the bonding performance from not meeting the on-site use requirements.

[0041] 5. The curing speed, physical properties and adhesiveness of the cast polyurethane material can meet the requirements of various types of on-site damage repairs of coal mine conveyor belts. Specific embodiments

[0042] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0043] A cast polyurethane material that complies with MT / T 113-1995 "Rules" and its construction process in conveyor belt repair of the present invention is an excellent solution to solve various types of damage problems of conveyor belts.

[0044] The present invention is a cast polyurethane material formula and its construction process in conveyor belt damage repair.

[0045] The cast polyurethane material formula includes:

[0046] 100 parts of component A;

[0047] 8-20 parts of component B; adjusted according to the reaction speed;

[0048] 5-25 parts of component C; adjusted according to the flame retardant requirement level;

[0049] 0.5-10 parts of component D; adjusted according to the antistatic requirement level;

[0050] 102-106 parts of component E;

[0051] The component A is a masterbatch, that is, a terminal NCO polyurethane prepolymer formed by the reaction of a macromolecular polyol and an isocyanate (such as TDI, MDI, etc.);

[0052] The component B is a curing agent, that is, an aromatic diamine compound;

[0053] The component C is a flame retardant, that is, expandable graphite powder;

[0054] The component D is an antistatic liquid;

[0055] The component E is an interface agent.

[0056] Preferably, the component A needs to select a masterbatch with a viscosity below 5000 mpas at 25°C to ensure good fluidity and achieve one-time forming for repairing damage problems by casting;

[0057] Preferably, the component B is 3,5-dimethylthiotoluenediamine or 3,3'-diethyl-4,4'-diaminodiphenylmethane;

[0058] Preferably, the expandable graphite of the component C is selected with a mesh number range of 30 - 300 meshes;

[0059] Preferably, the component D is a dioxo-ester quaternary ammonium salt;

[0060] Preferably, the component E is trichloroisocyanuric acid after dissolution.

[0061] The construction process of the cast polyurethane material in the repair of conveyor belt breakage includes the following steps:

[0062] Step 1: Grind the damaged part of the conveyor belt to be repaired with a tungsten carbide grinding disc or a wire wheel to expose a clean surface;

[0063] Step 2: Apply the component E to the part to be repaired;

[0064] Step 3: Mix the component A, component B, component C, and component D together and stir evenly;

[0065] Step 4: Quickly pour the mixture stirred in Step 3 onto the conveyor belt to be repaired, and let it level naturally or quickly scrape it flat with a scraper;

[0066] Step 5: The casting in Step 4 can achieve surface curing within fifteen minutes and meet the requirements of the mine for starting the machine within sixty minutes.

[0067] Preferably, in Step 3, when mixing, the component D can be added to the component B first;

[0068] Preferably, in Step 3, when mixing, the component D can be added to the component A first;

[0069] Preferably, in Step 3, when mixing, the component C can be added to the component B first;

[0070] Preferably, in Step 3, when mixing, the component C can be added to the component A first;

[0071] Preferably, in Step 3, when mixing, the component C and the component D can be added to the component B first;

[0072] Preferably, in Step 3, when mixing, the component C and the component D can be added to the component A first.

[0073] Working principle

[0074] Table 1 Basic parameter items of the cast polyurethane material of the present invention

[0075] Selection Criteria for Basic Phases Unit Standard Range Material Temperature ℃ Internal Company Standard 25 Viscosity mPa.s Internal Company Standard 2000～5000 Gel Time min Internal Company Standard 2～3 Ratio (Prepolymer:Curing Agent) Internal Company Standard 100:8～100 Finished Product Hardness Shore A GB / T531.1-2008 70～100 100% Modulus MPa GB / T528-2009 Greater than 8 300% Modulus MPa GB / T528-2009 Greater than 14 Tensile Strength MPa GB / T528-2009 Greater than 30 Elongation at Break ％ GB / T528-2009 Greater than 350 Right Angle Tear Strength KN / M GB / T529-2008 Greater than 70 Impact Resilience ％ GB / T1681-2009 Greater than 40 DIN Abrasion mm3 GB / T9867-2008 Less than 60

[0076] The test of the bonding strength between the basic item and rubber, which is one of the material quality indicators of the present invention. The bonding strength between the material of the present invention and the conveyor belt rubber should meet the usage requirements of inappropriate glue (the technology and process of bonding between the basic phase and rubber are well-known to professionals in this field and are not the claims of this patent. They are also the E1 and E2 functions of this product, so no further elaboration will be made here).

[0077] When adding antistatic agents to polyurethane materials, the reaction principle and product type of their characteristics need to be considered. Polyurethane materials are formed by the reaction of raw materials such as polyols, crosslinking agents, catalysts, chain extenders, and isocyanates. Therefore, adding antistatic agents can effectively eliminate or reduce static electricity generated by stray current, thereby preventing static electricity discharge caused by excessive static electricity accumulation and potential fire and explosion accidents.

[0078] However, for polyurethane materials to meet the requirements of MT / T113 - 1995 "Rules", the addition amount should be at least above 5%. But most antistatic liquids are viscous oily liquids. Adding a qualified antistatic liquid alone will cause an infiltrated film on the surface, and it will also have a certain impact on the compatibility of the product, resulting in the precipitation problem of oily substances on the surface, thus affecting on-site bonding and the physical properties of the product. It cannot meet the requirements for on-site conveyor belt damage repair. (The selection of antistatic agents is determined according to the basic item formula. The selection should not react with the substances in the basic phase, which is well-known to professionals in this related technology and is not the claim of this patent, so no further elaboration will be made here)

[0079] The technical principle of the present invention. Through the special physical properties of expandable graphite in component C, it has both excellent flame retardant effects and good electrical conductivity and liquid-phase adsorption lipophilicity (because most antistatic agents are oily, the lipophilicity of its graphite can evenly lock the antistatic agent, avoiding the precipitation of oily substances and affecting the bonding performance). Through the synergistic principle of these two substances, the usage amount of the antistatic agent is reduced, and problems such as the precipitation of oily substances are avoided, which may otherwise lead to the bonding performance not meeting on-site use requirements.

[0080] Due to the synergism with expandable graphite, the addition amount of the antistatic agent is reduced from more than 5% originally to less than 2%, enabling the product to meet the requirements of MT / T113 - 1995 "Rules", and the curing speed, physical properties, and adhesiveness can all meet the requirements for various types of on-site damage repairs of coal mine conveyor belts.

[0081] 1.4 The reason why existing products have not been able to achieve products that meet the requirements of MT / T113 - 1995 "Rules" is that there are various types of flame retardants, mainly including halogen-based flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, etc. The technical difficulty lies in that whether it is a reactive flame retardant or an additive flame retardant, the addition amount to reach the standard needs to be between 20% and 30%.

[0082] For example, most of the repair adhesive products on the market use two-component AB, and most of them are flame-retardant but without antistatic properties. The technical principle is that most of them use reactive flame retardants, but the addition amount within the standard range needs to be between 20% and 30%. However, when the addition amount is more than 20%, it will affect the reaction speed of polyurethane. After adding the flame retardant to the white polyurethane material, the physical properties will change to a certain extent, mainly manifested in aspects such as hardness, tensile strength, and flexural strength. Some studies have shown that under the appropriate addition amount of the flame retardant, the physical properties of the white polyurethane material can be improved, but too high an addition amount of the flame retardant will lead to a decrease in physical properties, problems such as cracking will occur, and at the same time, a precipitation phenomenon will occur, resulting in a significant reduction in the bonding performance and even being unable to meet the use requirements. Therefore, most of the repair adhesives on the market. Most of their products have a long curing time and low initial strength. Due to the particularity of coal mine production, the maintenance time is relatively short. Before the materials are completely cured after repair, the production is started, resulting in low overall repair quality, few problems solved, and unsatisfactory effects. It is almost used for the wear repair on the surface of the tape and the scratches that are not stressed, and cannot solve the damage problems that require high bonding strength and physical strength of the material, such as longitudinal tearing, edge defect restoration, and edge cracking. Because it only meets the flame retardant requirements, the product performance cannot meet the on-site use, so its product cannot add antistatic agents.

[0083] The technical path achieved by this invention is to select a new type of functional carbon material, expandable graphite. Expandable graphite can instantaneously expand its volume by 150 - 300 times when encountering high temperature, changing from flaky to worm-like. It has the characteristics of non-toxic and pollution-free. Using it alone or mixing it with other flame retardants can achieve an ideal flame retardant effect. When expandable graphite achieves the same flame retardant effect, the dosage is much less than that of ordinary flame retardants, and the addition amount within 15% can meet the standard. Because this material belongs to inorganic substances, it will not affect the physical properties and curing speed of the material itself.

[0084] Its working principle is: at high temperature, expandable graphite expands rapidly, instantaneously expanding its volume by 150 - 300 times, suffocating the flame. At the same time, the generated graphite expanded material covers the surface of the substrate, isolating the heat energy radiation and the contact with oxygen. The acid radicals inside its interlayer are released during expansion, which also promotes the carbonization of the substrate, thus achieving good effects through multiple flame retardant methods.

[0085] The technical principle of the present invention is based on the special physical properties of expandable graphite in Component C. It not only has excellent flame retardant effects but also good electrical conductivity and liquid-phase adsorption lipophilicity (since most antistatic agents are oily, the lipophilicity of the graphite can evenly lock the antistatic agent, preventing the precipitation of oily substances and affecting the bonding performance). As a result, the product meets the requirements of MT / T113 - 1995 "Rules", and the curing speed, physical properties, and adhesiveness are not significantly reduced due to the addition of flame retardants and antistatic agents in the original technology. Therefore, the product of the present invention not only meets the requirements of MT / T113 - 1995 "Rules" but also ensures the quality of the product in various types of belt breakage repairs.

[0086] Construction process description for various types of belt breakage problems: Common belt breakage problems include edge cracking, edge defect restoration, longitudinal tear, band tear, holes, surface rubber peeling, wear, and scratches. The most difficult problems to repair are edge defects, edge cracking, band tear, and longitudinal tear in sequence. For the above four difficult-to-repair problems, existing single products cannot repair them, and multiple products need to be used in combination. For example, in the case of longitudinal tear repair, a repair strip needs to be adhered to the back of the conveyor belt first, then the conveyor belt is rotated to the working surface to inject repair glue, and a layer of repair strip is covered on the repair glue. Regardless of whether the product meets the standards and the repair quality, the process is cumbersome and significantly increases the repair time.

[0087] The present invention relates to a construction process of a cast polyurethane material that meets the requirements of MT / T113 - 1995 "Rules" in the repair of conveyor belt breakage. The invention fills the blank in the conveyor belt repair field where materials meet the requirements of MT / T113 - 1995 "Rules". The unique one-time casting process replaces the existing complex repair process, significantly improving the repair speed, requiring no special tools, having low labor intensity, simple process, and high repair quality.

[0088] Practical case surface: A polyether-based polyurethane material that meets the requirements of MT / T113 - 1995 "Rules" and its construction process in the repair of conveyor belt breakage according to the present invention is an excellent solution to solve various types of conveyor belt breakage problems.

[0089] The present invention relates to a construction process of a cast polyurethane material that meets the requirements of MT / T113 - 1995 "Rules" in the repair of conveyor belt breakage. The invention fills the blank in the conveyor belt repair field where materials meet the requirements of MT / T113 - 1995 "Rules". The unique one-time casting process replaces the existing complex repair process, significantly improving the repair speed, requiring no special tools, having low labor intensity, simple process, and high repair quality.

[0090] The present invention is a new material, new process, and new technology with novelty, creativity, and practicality, and realizes an excellent solution for a product to repair various types of damage to conveyor belts.

[0091] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. The formula of casting polyurethane material is characterized by: include: Component A: 100 parts; Component B 8-20 parts; Adjust according to reaction speed; Component C 5-25 parts; Adjust according to the flame retardant requirement level; Component D: 0.5-10 parts; adjusted according to the antistatic level required; Component E 102-106 parts; The A component is a masterbatch, i.e., a terminal NCO polyurethane prepolymer formed by the reaction of a macromolecular polyol and an isocyanate (such as TDI, MDI, etc.); The B component is a curing agent, i.e. an aromatic diamine compound; The component C is a flame retardant, namely expandable graphite powder; The D component is an antistatic liquid; The E component is an interface agent.

2. The pouring polyurethane material formula according to claim 1, characterized in that: The component A should be a masterbatch with a viscosity of less than 5000 mPa s at 25°C; The B component is 3,5-dimethylthiotoluenediamine or 3,3'-diethyl-4,4'-diaminodiphenylmethane; The C component is expandable graphite with a mesh size range of 30-300 mesh; The D component is a dioxy-ester quaternary ammonium salt; The E component is dissolved trichloroisocyanuric acid.

3. The construction process of the cast polyurethane material in the repair of conveyor belt damage according to claim 1 is characterized in that: The steps include: Step 1: Use a tungsten steel grinding disc or a wire wheel to grind the damaged part of the conveyor belt that needs to be repaired to expose the clean surface; Step 2: Apply component E to the area that needs repair; Step 3: Mix component A, component B, component C and component D together and stir evenly; Step 4: Quickly pour the mixture prepared in step 3 onto the conveyor belt that needs to be repaired, and level it naturally or quickly scrape it with a scraper; The poured materials in step 5 and step 4 can reach surface solidification within 15 minutes and meet the mine's start-up requirements within 60 minutes.

4. The construction process of the cast polyurethane material in conveyor belt maintenance according to claim 1 is characterized in that: In the step 3, during mixing, component D can be added into component B first.

5. The construction process of the cast polyurethane material in the maintenance of conveyor belt according to claim 1, characterized in that: In the step 3, during mixing, component D can be added into component A first.

6. The construction process of the cast polyurethane material in the conveyor belt maintenance according to claim 1 is characterized in that: In the step 3, during mixing, component C can be added into component B first.

7. The construction process of the cast polyurethane material in the maintenance of conveyor belt according to claim 1, characterized in that: In the step 3, during mixing, component C can be added into component A first.

8. The construction process of the cast polyurethane material in conveyor belt maintenance according to claim 1, characterized in that: In the step 3, during mixing, components C and D may be added to component B first.

9. The construction process of the cast polyurethane material in conveyor belt maintenance according to claim 1, characterized in that: In the step 3, during mixing, components C and D may be added to component A first.