CN109650923B

CN109650923B - Detachable nano heat insulation sleeve of steam turbine

Info

Publication number: CN109650923B
Application number: CN201910063161.8A
Authority: CN
Inventors: 魏晶; 何新平
Original assignee: Beijing Zhonghuan Xinhui Technology Co ltd
Current assignee: Beijing Zhonghuan Xinhui Technology Co ltd
Priority date: 2019-01-23
Filing date: 2019-01-23
Publication date: 2021-10-08
Anticipated expiration: 2039-01-23
Also published as: CN109650923A

Abstract

The invention belongs to the field of turbine thermal insulation and heat preservation, and particularly relates to a nano thermal insulation material and a detachable turbine nano thermal insulation sleeve prepared from the nano thermal insulation material. The nano heat insulating material of the present invention contains hollow ZrO₂75-80 wt.% fiber, hollow Al₂O₃10-15 wt.% of nanospheres, 3-6 wt.% of nano calcium titanium aluminate and 2-6 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material. The detachable turbine nanometer heat-insulating sleeve prepared by the nanometer heat-insulating material has excellent compression strength and bending strength and very low heat conductivity coefficient, thereby greatly improving the heat-insulating and heat-preserving effect; the heat insulation sleeve is convenient to detach and can be repeatedly used, the maintenance is very convenient, the use cost is greatly lowered, and the service life is well prolonged.

Description

Detachable nano heat insulation sleeve of steam turbine

Technical Field

The invention belongs to the field of turbine thermal insulation and heat preservation, and particularly relates to a nano thermal insulation material and a detachable turbine nano thermal insulation sleeve prepared from the nano thermal insulation material.

Background

A steam turbine, also known as a steam turbine engine, is a rotary power steam power plant that converts the energy of steam into mechanical work. It is mainly used as a prime mover for power generation, and can also directly drive various pumps, fans, compressors, ship propellers and the like; the exhaust steam or intermediate extraction steam of the steam turbine can be used for meeting the heat supply requirements in production and life. During the use of the steam turbine, the steam turbine needs to be insulated. At present, in some power plants, because the structural design of a heat insulation device of a steam turbine body is unreasonable, heat insulation materials are selected improperly, the temperature difference between an upper cylinder and a lower cylinder is large in the operation of a unit, the temperature difference between the inner wall and the outer wall of a cylinder and the inner wall and the outer wall of a flange is large, the unit is seriously deformed, and the safe operation of the unit is influenced. But also the loss of a large amount of heat energy or cold energy is usually caused when the device runs at high temperature or low temperature, for example, a steam turbine generator set and the like, when the device runs at high temperature, the shell of the device is always exposed in the space to cause a large amount of heat loss, and if the device runs in winter or in northern cold places, the loss of heat is considerable, thereby not only influencing the energy utilization rate of the device, but also influencing the running efficiency of the device to greatly increase the running cost,

one of the commonly used heat preservation methods at present is to wrap the heat preservation material such as slag wool, glass wool and the like outside the steam turbine, fix the heat preservation material on the shell of the steam turbine by using glass fiber cloth or a ribbon, and finally coat asphalt oil or wrap iron sheets. When the method is used for construction and installation, the steam turbine shell is difficult to be wrapped by the heat insulation material according to a proper size, a gap is generated between the heat insulation material and the steam turbine shell, heat loss is easy to cause, and the heat insulation effect is poor; the waterproof performance is poor, and the shell of the steam turbine is easy to corrode; the device can be used only once, and can be dismantled when in overhaul, so that resource waste is caused, and the labor cost is high; the installation process is complicated and brings inconvenience to constructors. Moreover, the heat insulation and preservation material is fixed by the wire netting, so that the heat insulation effect is poor, dust is easily generated in the coating procedure, and the operation worker is not healthy.

The other one of the common heat preservation methods is to lay an inner heat preservation layer made of, for example, an aluminum silicate needle-punched blanket on the cylinder body, and then to use lime or cement as an outer protection layer for plastering, because an expansion groove is usually required to be formed on the plastering material, the heat preservation effect and the appearance are not good, and the maintenance is not convenient. When the method is used for heat preservation, the protective layer and the heat preservation layer are required to be completely destroyed to be dismantled when the steam turbine is overhauled, so that a large amount of waste is generated, great waste and serious environmental pollution are caused, and the method is determined to be only used once and has high use cost.

For example, chinese patent CN 201043478Y discloses a special insulating layer structure for a steam turbine, which is formed by coating at least one inner insulating layer on the surface of a steam turbine shell, wherein an outer protective layer made of stainless steel plate or glass fiber reinforced plastic is coated outside the inner insulating layer; the inner heat-insulating layer is composed of a plurality of detachable heat-insulating cotton blankets, each heat-insulating cotton blanket is at least composed of heat-insulating materials and connecting pieces, the outer protective layer is formed by splicing block-shaped shells made of stainless steel or glass fiber reinforced plastics, the inner heat-insulating layer can also be an integral heat-insulating layer made of at least one of aluminum silicate cotton, rock wool and glass wool, and the heat-insulating layer is firmly bound and connected by steel belts or iron wires. Although the patent partially solves some technical problems in the heat preservation of the existing steam turbine, the installation and the removal of the block-shaped shell of which the outer protective layer is made of stainless steel or glass fiber reinforced plastic are complicated, and inconvenience is brought to construction; the construction method is easy to damage during construction, and cannot be reused, so that resource waste is caused; in the environment with high temperature and more water vapor, the paint is easy to deteriorate and corrode, and the safety performance is reduced.

The flexible thermal insulation coat disclosed in the Chinese patent CN 2791263Y is formed by splicing a plurality of thermal insulation blocks designed according to the appearance of a steam turbine, wherein the thermal insulation blocks are three layers: the lining and the protective layer are made of high-temperature-resistant composite coating fiber cloth, the heat-insulating layer is made of high-temperature-resistant heat-insulating material, the lining and the protective layer are fixed on the protective layer by high-temperature-resistant rivets, and the periphery of the lining and the protective layer is sewn by high-temperature-resistant threads; the heat-insulating blocks are connected by adjustable high-temperature-resistant ropes or high-temperature-resistant fiber belts. Although the patent partially solves some technical problems in the heat preservation of the existing steam turbine, the heat preservation layer is not tightly attached to the steam turbine because the fixing mode adopts the heat preservation layer fixed on the protective layer by the high-temperature resistant rivet, and the heat preservation effect is not ideal; and the installation and the removal are inconvenient, and the protective layer or the heat-insulating layer is easy to damage, so that the heat-insulating layer cannot be reused.

The heat-insulating layer structure of the steam turbine disclosed in chinese patent CN 202690147U comprises at least one heat-insulating layer coated on the surface of the casing of the steam turbine, the outer surface of the heat-insulating layer is further coated with an outer protective layer made of a nano composite material, and the outer protective layer is formed by splicing a plurality of protective blocks made of the nano composite material. This patent utilizes the concatenation of polylith heat preservation piece to constitute whole heat preservation, compares traditional method, and the aspect of its and the steam turbine surface size cooperation obviously improves, still has the seam many, installs complicacy, the bulk strength is relatively poor, the higher problem of appearance temperature.

For example, chinese patent CN 1888398A discloses a heat preservation method and a heat preservation cabin for a steam turbine cylinder shell, the heat preservation method comprises: firstly, manufacturing a certain number of block-shaped heat preservation blankets according to the surface shape and size of a cylinder shell, and paving one heat preservation blanket on the surface of the steam turbine shell to form at least two heat preservation layers; the heat-insulating layer is formed by the following steps: the method comprises the steps of firstly paving a heat insulation layer formed by splicing block heat insulation blankets on the surface of an outer shell of the steam turbine, then splicing a heat insulation layer formed by the same or different block heat insulation blankets on the heat insulation layer, covering an upper heat insulation blanket in a connecting gap formed between the two heat insulation blankets in a lower heat insulation layer when an upper heat insulation layer is spliced, and forming a staggered shape on the upper heat insulation blanket and the lower heat insulation blanket. Although the heat preservation cabin provided by the document has the advantages of low use cost, convenient assembly, quick disassembly and assembly and reusability, the heat preservation blanket is made of conventional heat preservation materials, such as aluminum silicate, rock wool or glass wool, and is wrapped by stainless steel wire cloth or high-temperature resistant aluminum silicate fiber cloth, so that the overall heat preservation and heat insulation effect is not ideal.

The steam turbine insulating sleeve disclosed in the Chinese patent CN 204371431U structurally comprises an insulating sleeve main body and is characterized in that a heat-insulating cavity is arranged in the insulating sleeve main body, and a plurality of hollow spheres are arranged in the heat-insulating cavity; a sponge layer, a foam layer and an iron sheet layer are sequentially arranged above the heat insulation cavity; and a fiber cloth layer, a high-temperature-resistant insulating layer and a refractory coating are sequentially arranged below the heat-insulating cavity. Although the insulating jacket of this document has the advantages of simple structure and convenience in use, the insulating performance is not satisfactory in general.

The detachable heat preservation device for the steam turbine body, disclosed in Chinese patent CN 204312145U, comprises fastening nuts, pressure strips, fixing studs, flange bolts, flange nuts, intermediate joints, cylinders and flanges, and is characterized in that: the heat insulation layer also comprises a plastering layer, an expansion joint, an inner layer reinforcing mesh, a middle layer reinforcing mesh, aluminum silicate wool, an inner heat insulation layer, a middle heat insulation layer and an outer heat insulation layer; the outer heat-insulating layer, the middle heat-insulating layer and the inner heat-insulating layer are sequentially arranged from outside to inside in a stacked mode, and the inner wall of the inner heat-insulating layer is in contact with the cylinder and the flange; the outer wall of the outer heat-insulating layer is coated with the plastering layer, and the outer heat-insulating layer is provided with a plurality of expansion joints; the fixing studs are arranged among the outer heat-insulating layer, the middle heat-insulating layer and the inner heat-insulating layer, penetrate through the outer heat-insulating layer, the middle heat-insulating layer and the inner heat-insulating layer and are screwed and fixed through the battens and the fastening nuts; the left side and the right side of the flange are respectively and symmetrically provided with two flange bolts, the tight installation of the flange is ensured by screwing the flange nuts, and a layer of aluminum silicate wool is wrapped outside the flange bolts. Although the temperature difference of each part of the steam turbine body is reduced to a certain extent, the excessive thermal stress generated by the steam turbine body is prevented, and the steam turbine can be safely operated for a long time. However, the heat preservation device of the document has a complex structure and high construction difficulty, and greatly increases the production cost; and the heat preservation and insulation effect is still not ideal.

In summary, the existing turbine insulation sleeve is inconvenient to use, easily damages the turbine shell and affects the normal operation of equipment, and particularly, for the insulation sleeve which is not detachable or can not be reused, the problem that the equipment is inconvenient to repair and maintain and the use cost is very high often exists, or the insulation sleeve is detachable and is relatively convenient to use, but the actual insulation effect is still not ideal enough, so that the service life of the insulation sleeve is shortened.

Disclosure of Invention

Therefore, the technical problem to be solved by the present application is how to provide a detachable turbine nanometer thermal insulation sleeve, which has a very low thermal conductivity and excellent compression and bending strength, so as to greatly improve the thermal insulation effect and effectively maintain the efficient operation of the turbine; the heat insulation sleeve is convenient to detach and can be repeatedly used, the maintenance is very convenient, the use cost is greatly lowered, and the service life is well prolonged.

In order to solve the technical problems, the inventor of the present application has earnestly studied and found that a nano heat insulating material with synergistic effect is prepared, and a nano heat insulating material with specific composition is adopted to prepare a detachable turbine nano heat insulating sleeve, so that the problems of high heat conductivity coefficient and poor heat insulating and heat preserving effect of the existing turbine heat insulating sleeve can be greatly reduced, and the problems of inconvenient installation or detachment of the existing turbine heat insulating sleeve, easy damage to a turbine shell, influence on normal operation of equipment and overhigh use cost can be avoided, thereby well solving the technical problems.

The technical scheme of the application is as follows: in one aspect, the present application discloses a nano thermal insulation material comprising:

the weight percentage of each component is based on the weight of the nano heat-insulating material.

Hollow ZrO described herein₂The fibre content is preferably 76.5-78.5 wt.%, more preferably 77.2-77.8 wt.%, most preferably 77.6 wt.%.

Hollow ZrO described herein₂The fiber can be prepared by a method known in the art, for example, mixing the raw material zirconium salt and a stabilizer (such as yttrium nitrate), dissolving the mixture in an ethanol water solution to prepare a precursor solution, then soaking a template agent (such as lalang grass fiber, silk, cotton, kapok and the like) in the precursor solution, taking out the soaked template agent fiber, squeezing, drying and roasting.

Hollow Al described in the present application₂O₃The nanosphere content is preferably 11.5-14.5 wt.%, more preferably 12.5-14.0 wt.% parts, most preferably 13.5 wt.%.

Hollow Al described in the present application₂O₃Nanospheres, preferably having a particle size of 40-130 nm; more preferably, the nanoparticles are composed of nanoparticles of different particle diameters in the following ratio, wherein>100-130nm：>70-100 nm: 40-70nm ═ 1-2:2-3:1-2 (by weight), more preferably 40-70nm ═ 1-2:2-3:1-2 (by weight)>100-130nm：>70-100 nm: 40-70 nm-1: 2.5:1.5 (weight ratio). Using hollow Al of different particle sizes₂O₃The nanospheres can form a more dense packing structure to form a vacuum wall formed by combining a large number of vacuum cavities, and the structure can effectively prevent heat conduction and cooperate with the hollow ZrO₂The fiber and other components improve the heat insulation performance of the nano heat insulation material.

Hollow Al described in the present application₂O₃Nanospheres can be prepared using methods known in the art, for example, the preparation method described in CN 108585842A.

The nano-titanium calcium aluminate content described herein is preferably 3.5-5.5 wt.%, more preferably 4.0-5.0 wt.%, most preferably 4.3 wt.%.

The particle size of the nano calcium titanium aluminate is preferably 50-120nm, and more preferably 70-90 nm.

The nano calcium titanium aluminate can be prepared by performing superfine treatment on a calcium titanium aluminate raw material, preferably performing titanium removal treatment for removing titanium dioxide on the calcium titanium aluminate raw material before the superfine treatment, so that the CA with lamellar crystal form in the calcium titanium aluminate can be increased₆Content of phase. Due to the lamellar crystal form of CA₆The phase has extremely low thermal conductivity, thereby being beneficial to reducing the thermal conductivity of the nano heat-insulating material and correspondingly improving the heat insulation and heat preservation effects of the nano heat-insulating material.

The nano ZnO coated potassium hexatitanate whiskers described herein preferably have a content of 2.5-5.5 wt.%, more preferably 3.5-5.0 wt.%, and most preferably 4.6 wt.%.

In the nano ZnO coated potassium hexatitanate whisker, the nano ZnO content is 1-3 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The nano ZnO coated potassium hexatitanate whiskers described herein can be prepared by methods known in the art, such as inorganic coating of potassium hexatitanate whiskers by heterogeneous nucleation, using ethyl acetate over Na₂Zn(OH)₄Hydrolyzing in the solution to obtain a precursor of the hydroxide coated whisker, and calcining to obtain the nano ZnO coated whisker.

On the other hand, the application also discloses a preparation method of the detachable turbine nanometer heat-insulating sleeve, which comprises the following steps:

1) firstly hollow ZrO₂Uniformly chopping the fiber into short fiber of 0.5-1.5mm, and then cutting the hollow ZrO into pieces₂Fiber, hollow Al₂O₃Uniformly mixing the nanospheres, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal according to the proportion;

2) adding a proper amount of deionized water and an optional pH value regulator into the composition obtained in the step 1) to form a suspension;

3) slowly injecting the suspension obtained in the step 2) into a forming die corresponding to each part of the steam turbine, and performing filter pressing forming;

4) drying the formed prefabricated part obtained in the step 3) to constant weight;

5) sintering the dried prefabricated part, and then cooling to room temperature;

6) splicing the molded sintered part prepared in the step 5) on the surface of the steam turbine in situ to form the nanometer heat-insulating sleeve of the steam turbine.

The solids content of the suspension in said step 2) is preferably 50-75 wt.%, more preferably 60-65 wt.%, most preferably 62 wt.%.

In the step 2), acid, such as inorganic acid, preferably hydrochloric acid, nitric acid and the like is preferably added as a pH value regulator; the pH of the suspension is preferably adjusted to a value of 5.5 to 6.5, more preferably 6.0.

The pressure in the step 3) is 0.1-0.6MPa, preferably 0.2-0.4MPa, and more preferably 0.25 MPa.

The drying temperature in the step 4) is 30-90 ℃, preferably 50-70 ℃, and more preferably 65 ℃.

The drying time in the step 4) is 2-10h, preferably 5-7h, and more preferably 6 h.

The drying of step 4) may be performed in a drying apparatus commonly used in the art, such as an oven.

In the step 5), the temperature is firstly raised to 750-; keeping the temperature for 0.5-2.5h, preferably 1-2 h; then the temperature is raised to 1200-1350 ℃, preferably 1250-1300 ℃; keeping the temperature for 1.0-3.0h, preferably 1.5-2.5 h; the heating rate is 6-12 deg.C/min, preferably 8-11 deg.C/mi.

And in the step 6), the molded sintering parts can be fixedly connected through a lock catch, a buckle or a belt type connecting buckle.

On the other hand, the application also discloses a detachable turbine nanometer heat-insulating sleeve prepared by the preparation method.

The application has the beneficial effects that:

1. the nano heat-insulating material with a specific composition is adopted, so that the synergistic effect is realized, and compared with the existing heat-insulating and heat-preserving material for the steam turbine, the nano heat-insulating sleeve of the detachable steam turbine, which is made of the nano heat-insulating material, has a significantly lower heat conductivity coefficient, so that the heat-insulating and heat-preserving effect is greatly improved.

2. The utility model provides a can dismantle adiabatic cover of steam turbine nanometer has excellent compressive strength and bending strength except having lower coefficient of heat conductivity, make it not only to stop all parts of steam turbine to external extra heat conduction loss from this, and can play the effect of avoiding radiation heat transfer and protection steam turbine part, can ensure the safe lasting operation of steam turbine unit, can dismantle the adiabatic cover of steam turbine nanometer and can avoid because the dust that the steam turbine motion vibration produced, guarantee the long-term safe operation of steam turbine, high durability and convenient use, the cost is lower, the value of popularization and application has.

3. The utility model provides a can dismantle adiabatic cover of steam turbine nanometer can splice into adiabatic cover wholly with the shaping sintered part that makes on the spot on the steam turbine, and it can be according to the different temperature subregion of steam turbine and different shapes come the different shaping prefabs of body-building, therefore has very strong adaptability, can match different specifications, the steam turbine of equidimension well.

4. ZrO as the principal raw material for use in this application₂Fiber, Al₂O₃The nanosphere, the calcium titanium aluminate and the like are rich in sources and low in cost, and the production process is simple, so that the production cost is greatly reduced.

5. The present application is based on the introduction of hollow ZrO₂The fiber not only retains the excellent normal-temperature mechanical property, high-temperature resistance and corrosion resistance of the zirconia material; and the zirconia fiber is made into a hollow structure, so that the heat insulation performance of the zirconia fiber is greatly improved on the basis of the solid fiber.

6. The application is realized by forming a hollow ZrO layer₂Hollow Al is further introduced into the fiber₂O₃Nanospheres of hollow Al₂O₃The nanospheres act as a reinforcing material to some extent, thereby improving the hollow ZrO₂Mechanical strength of the fiber, and hollow Al₂O₃The nanosphere can also effectively seal hollow ZrO₂The two ends of the fiber are hollow to form an airtight structure, thereby effectively reducing the content of the nano-insulation materialThe coefficient of heat conductivity is increased, thereby greatly improving the heat insulation performance of the finally prepared detachable turbine nanometer heat insulation sleeve.

Additional advantages will be set forth in part in the description which follows and in part will be obvious from the description, or may be learned by practice of the invention. The following advantages are realized and attained, particularly in light of the chemical compositions, methods, and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive.

Supplemental definition

The materials, compounds, compositions, and components described herein can be used in, or can be used in combination with, the methods and compositions described herein, or can be used in the practice of the methods and in the preparation of the compositions, or as products obtained by the methods. It is to be understood that when combinations, subsets, groups, etc. of these materials are disclosed, each and every combination and permutation of these compounds are specifically contemplated and described herein, although these may not be explicitly specifically mentioned. For example, if an extraction aid component is disclosed and discussed, and a number of alternative solid state forms of that component are discussed, each and every combination and permutation of the possible reference aid components and solid state forms is specifically contemplated unless specifically indicated to the contrary. This concept applies to all aspects of this application, including but not limited to steps in methods of making and using the disclosed compositions. Thus, if there are a plurality of additional steps that can be performed it is understood that each of these additional steps can be performed by any specific embodiment or combination of embodiments of the disclosed methods, and that each such combination is specifically contemplated and should be considered disclosed.

In this specification and in the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings:

it must be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include both one and more than one (i.e., two, including two) unless the context clearly dictates otherwise. Thus, for example, reference to "the flame retardant" can include a single flame retardant, or a mixture of two or more flame retardants, and the like.

"optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not. For example, the phrase "adding an optional pH adjuster" means that the pH adjuster may or may not be added, and the description includes both the case where no pH adjuster is added and the case where a pH adjuster is added.

Unless otherwise indicated, all numerical points or ranges of values in this application should be understood as being preceded by the term "about," i.e., it is approximate, and thus may include values outside of the stated range. Ranges of values may be expressed herein directly from one particular value to another or from "about" one particular value to "about" another particular value. When such a range of values is expressed, another aspect includes from the one particular value and/or to the other particular value. Similarly, some numerical points may be expressed as numerical values directly or by using the antecedent "about" to indicate approximate values. It will be further understood that the endpoints of each of the numerical ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

Reference in the specification and concluding claims to parts by weight of a particular element or component in a composition or article refers to the weight relationship between that element or component and any other elements or components in the composition or article, expressed as parts by weight. Thus, in a composition comprising 2 parts by weight of component X and 5 parts by weight of component Y, X and Y are present in a weight ratio of 2:5 and are present in this ratio regardless of whether additional components are included in the composition.

Unless specifically indicated to the contrary, or implied by the context or customary practice in the art, all parts and percentages referred to herein are by weight and the weight percentages of a component are based on the total weight of the composition or product in which it is included.

Reference throughout this application to "comprising," "including," "having," and similar language is not intended to exclude the presence of any optional components, steps or procedures, whether or not any optional components, steps or procedures are specifically disclosed. In order to avoid any doubt, all methods claimed through use of the term "comprising" may include one or more additional steps, apparatus parts or components and/or materials unless stated to the contrary. In contrast, the term "consisting of … …" excludes any component, step, or procedure not specifically recited or recited. Unless otherwise specified, the term "or" refers to the listed members individually as well as in any combination.

Furthermore, the contents of any referenced patent or non-patent document in this application are incorporated by reference in their entirety, especially with respect to definitions disclosed in the art (where not inconsistent with any definitions specifically provided herein) and general knowledge.

Detailed Description

The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices, and/or methods described and claimed herein are made and evaluated, and are intended to be purely exemplary and are not intended to limit the scope of what the inventors regard as their invention. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.) but some errors and deviations should be accounted for. Unless otherwise indicated, parts are parts by weight, temperatures are in degrees Celsius or at ambient temperature, and pressures are at or near atmospheric. There are many variations and combinations of reaction conditions (e.g., component concentrations, desired solvents, solvent mixtures, temperatures, pressures, and other reaction ranges) and conditions that can be used to optimize the purity and yield of the product obtained by the process. Only reasonable routine experimentation will be required to optimize such process conditions.

Example 1:

a nano heat insulating material a containing hollow ZrO₂75 wt.% fiber, hollow Al₂O₃13 wt.% of nanospheres, 6 wt.% of nano calcium titanate aluminate and 6 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material a.

Wherein, hollow Al₂O₃The particle size of the nanospheres is 80-120 nm; the particle size of the nano calcium titanium aluminate is 50 nm; in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 1 wt%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nanometer heat-insulating sleeve A by using the nanometer heat-insulating material a comprises the following steps:

firstly, hollow ZrO is formed₂The fibers were uniformly chopped into 0.5mm short fibers, which were then mixed with hollow Al₂O₃Uniformly mixing the nanospheres, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal in a mixer according to the proportion; deionized water was then added to the mixer and stirred to form a suspension with a solids content of 50 wt.%.

Then slowly injecting the suspension into a forming die corresponding to each part of the steam turbine, and performing filter pressing forming under the pressure of 0.1 MPa; then drying the obtained molded prefabricated member at 30 ℃ for 10 hours until the weight is constant; sintering the dried prefabricated part, wherein the temperature is firstly increased to 750 ℃, the temperature is preserved for 2.5 hours, then the temperature is increased to 1200 ℃, the temperature is preserved for 3.0 hours, the temperature increase rate is 6 ℃/min, and then the prefabricated part is cooled to the room temperature; and finally, splicing the prepared molded sintering piece on the surface of the steam turbine through a buckle to form the nanometer heat-insulating sleeve A of the steam turbine.

Example 2

A nano heat insulating material b containing hollow ZrO₂Fiber 80 wt.%, hollow Al₂O₃15 wt.% of nanospheres, 3 wt.% of nano calcium titanate aluminate and 2 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material b.

Wherein, hollow Al₂O₃The particle size of the nanospheres is 40-80 nm; the particle diameter of the nano calcium titanium aluminate is 120 nm; in the nano ZnO coated potassium hexatitanate whisker, the nano ZnO content is 3 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nanometer heat-insulating sleeve B by using the nanometer heat-insulating material B is as follows:

firstly, hollow ZrO is formed₂The fibers were uniformly chopped into 1.5mm short fibers, which were then mixed with hollow Al₂O₃Uniformly mixing the nanospheres, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal in a mixer according to the proportion; deionized water and hydrochloric acid, a pH adjuster, were then added to the mixer and stirred to form a suspension with a pH of 5.5 and a solids content of 75 wt.%.

Then slowly injecting the suspension into a forming die corresponding to each part of the steam turbine, and performing filter pressing forming under the pressure of 0.6 MPa; then drying the obtained molded prefabricated member for 2 hours at the temperature of 90 ℃ until the weight is constant; sintering the dried prefabricated part, wherein the temperature is firstly increased to 950 ℃, the temperature is preserved for 0.5h, then the temperature is increased to 1350 ℃, the temperature is preserved for 1.0h, the temperature increase rate is 12 ℃/min, and then the prefabricated part is cooled to the room temperature; and finally, splicing the prepared molded sintering piece on the surface of the steam turbine through lock catches to form a nanometer heat insulation sleeve B of the steam turbine.

Example 3

A nano heat insulating material c comprising hollow ZrO₂Fiber 76.5 wt.%, hollow Al₂O₃14.5 wt.% of nanospheres, 5.5 wt.% of nano calcium titanate aluminate and 3.5 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material c.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1: 2:1 (weight ratio); the particle size of the nano calcium titanium aluminate is 70 nm; in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 1.5 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nanometer heat-insulating sleeve C by using the nanometer heat-insulating material C comprises the following steps:

firstly, hollow ZrO is formed₂The fibers were uniformly chopped into 0.8mm short fibers, which were then mixed with hollow Al₂O₃Uniformly mixing the nanospheres, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal in a mixer according to the proportion; deionized water and nitric acid, a pH adjuster, were then added to the mixer and stirred to form a suspension with a pH of 6.5 and a solids content of 60 wt.%.

Then slowly injecting the suspension into a forming die corresponding to each part of the steam turbine, and performing filter pressing forming under the pressure of 0.2 MPa; then drying the obtained molded prefabricated member at 50 ℃ for 7 hours until the weight is constant; sintering the dried prefabricated part, wherein the temperature is firstly increased to 800 ℃, the temperature is preserved for 2h, then the temperature is increased to 1250 ℃, the temperature is preserved for 2.5h, the temperature increase rate is 8 ℃/min, and then the prefabricated part is cooled to the room temperature; and finally, splicing the prepared molded sintering piece on the surface of the steam turbine through lock catches to form the nanometer heat-insulating sleeve C of the steam turbine.

Example 4

A nano heat insulating material d containing hollow ZrO₂Fiber 78.5 wt.%, hollow Al₂O₃11.5 wt.% of nanospheres, 5.0 wt.% of nano calcium titanate aluminate and 5.0 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material d.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1: 2:2 (weight ratio); the particle size of the nano calcium titanium aluminate is 90 nm; in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 2.2 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nanometer heat-insulating sleeve D by using the nanometer heat-insulating material D is as follows:

firstly, hollow ZrO is formed₂The fibers were uniformly chopped into 1.2mm short fibers, which were then mixed with hollow Al₂O₃The nanosphere, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal are mixed in a mixerMixing uniformly according to the proportion; deionized water and a pH adjuster, sulfuric acid, were then added to the mixer and stirred to form a suspension having a pH of 6.2 and a solids content of 65 wt.%.

Then slowly injecting the suspension into a forming die corresponding to each part of the steam turbine, and performing filter pressing forming under the pressure of 0.4 MPa; then drying the obtained molded prefabricated member at 70 ℃ for 5 hours to constant weight; sintering the dried prefabricated part, wherein the temperature is firstly increased to 900 ℃, the temperature is kept for 1h, then the temperature is increased to 1300 ℃, the temperature is kept for 1.5h, the temperature increase rate is 11 ℃/min, and then the prefabricated part is cooled to the room temperature; and finally, splicing the prepared molded sintering piece on the surface of the steam turbine through a buckle to form a nanometer heat insulation sleeve D of the steam turbine.

Example 5

A nano heat insulating material e containing hollow ZrO₂Fiber 77.2 wt.%, hollow Al₂O₃14.0 wt.% of nanospheres, 4.0 wt.% of nano calcium titanate aluminate and 4.8 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material e.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1.5: 2:1.5 (weight ratio); the particle size of the nano calcium titanium aluminate is 80 nm; in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 2.8 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nanometer heat-insulating sleeve E by using the nanometer heat-insulating material E comprises the following steps:

firstly, hollow ZrO is formed₂The fibers were uniformly chopped into 1.0mm short fibers, which were then mixed with hollow Al₂O₃Uniformly mixing the nanospheres, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal in a mixer according to the proportion; deionized water and a pH adjuster, sulfuric acid, were then added to the mixer and stirred to form a suspension having a pH of 6.3 and a solids content of 63 wt.%.

Then slowly injecting the suspension into a forming die corresponding to each part of the steam turbine, and performing filter pressing forming under the pressure of 0.3 MPa; then drying the obtained molded prefabricated member at 65 ℃ for 6 hours to constant weight; sintering the dried prefabricated part, wherein the temperature is firstly raised to 850 ℃, the temperature is preserved for 1.5h, then the temperature is raised to 1275 ℃, the temperature is preserved for 2.0h, the temperature raising rate is 10 ℃/min, and then the prefabricated part is cooled to the room temperature; and finally, splicing the prepared molded sintering piece on the surface of the steam turbine through a belt type connecting buckle to form the nanometer heat-insulating sleeve E of the steam turbine.

Example 6

A nano heat insulating material f containing hollow ZrO₂Fiber 77.8 wt.%, hollow Al₂O₃12.5 wt.% of nanospheres, 5.0 wt.% of nano calcium titanium aluminate and 4.7 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material f.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1: 2.0:1.5 (weight ratio); the particle size of the nano calcium titanium aluminate is 85 nm; in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 1.8 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nanometer heat-insulating sleeve F by using the nanometer heat-insulating material F comprises the following steps:

firstly, hollow ZrO is formed₂The fibers were uniformly chopped into 1.1mm short fibers, which were then mixed with hollow Al₂O₃Uniformly mixing the nanospheres, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal in a mixer according to the proportion; deionized water and pH adjuster-hydrochloric acid were then added to the mixer and stirred to form a suspension with a pH of 6.0 and a solids content of 62 wt.%.

Then slowly injecting the suspension into a forming die corresponding to each part of the steam turbine, and performing filter pressing forming under the pressure of 0.25 MPa; then drying the obtained molded prefabricated member at 65 ℃ for 6 hours to constant weight; sintering the dried prefabricated part, wherein the temperature is firstly raised to 850 ℃, the temperature is preserved for 1.5h, then the temperature is raised to 1275 ℃, the temperature is preserved for 2.0h, the temperature raising rate is 10 ℃/min, and then the prefabricated part is cooled to the room temperature; and finally, splicing the prepared molded sintering piece on the surface of the steam turbine through lock catches to form a nanometer heat insulation sleeve F of the steam turbine.

Example 7

A nano heat insulating material g containing hollow ZrO₂Fiber 77.6 wt.%, hollow Al₂O₃13.5 wt.% of nanospheres, 4.3 wt.% of nano calcium titanium aluminate and 4.6 wt.% of nano ZnO coated potassium hexatitanate whiskers, based on the total weight of the nano thermal insulation material g.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1: 2.5:1.5 (weight ratio); the particle size of the nano calcium titanium aluminate is 85 nm; in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 1.8 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nano insulation cover G using the nano insulation material G is substantially the same as the process for preparing example 6 except that the nano insulation material is different.

Example 8

A nano-insulating material h having substantially the same composition as a nano-insulating material g except that: form a hollow Al₂O₃The nano-particles of the nanospheres have a particle size distribution of,>100-130nm：>70-100 nm: 40-70 nm-1: 2.5:1.0 (weight ratio).

The process for preparing the detachable turbine nano insulation sleeve H using the nano insulation material H is substantially the same as the process for preparing the detachable turbine nano insulation sleeve H of example 6, except that the nano insulation material is different.

Example 9

The nano insulating material g described in example 7 was directly used to prepare a detachable turbine nano insulating sleeve I, which was prepared substantially in the same manner as in example 4 except that the nano insulating material was used.

Comparative example 1

A nano heat insulating material j comprising hollow ZrO₂Fiber 77.6 wt.%, hollow Al₂O₃Nanosphere 33.4 wt.%, based on the total weight of nano-insulating material j.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1: 2.5:1.5 (weight ratio).

The process for preparing the detachable turbine nano insulation sleeve J using the nano insulation material J is substantially the same as the process for preparing the detachable turbine nano insulation sleeve J of example 6, except that the nano insulation material is different.

Comparative example 2

A nano heat insulating material k composed of hollow ZrO₂And (3) fiber composition.

The process for preparing the detachable turbine nano insulation sleeve K using the nano insulation material K is substantially the same as the process for preparing the detachable turbine nano insulation sleeve K in example 6, except that the nano insulation material is different.

Comparative example 3

A nano heat insulating material l containing hollow ZrO₂Fiber 77.6 wt.%, hollow Al₂O₃13.5 wt.% of nanosphere and 8.9 wt.% of nano titanium calcium aluminate, based on the total weight of the nano heat insulating material l.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1: 2.5:1.5 (weight ratio); the particle size of the nano calcium titanium aluminate is 85 nm.

The process for preparing the removable turbine nano insulation sheath L using the nano insulation material L is substantially the same as that of example 6 except that the nano insulation material is different.

Comparative example 4

A nano heat insulating material m containing hollow ZrO₂Fiber 77.6 wt.%, hollow Al₂O₃13.5 wt.% of nanospheres and 8.9 wt.% of nano ZnO coated potassium hexatitanate whiskers, and the nanospheres are used for nano heat insulationThe total weight of material m is the reference.

Wherein, hollow Al₂O₃The nanosphere has a particle size of 40-130nm and is composed of nanoparticles with different particle sizes at the following ratio>100-130nm：>70-100 nm: 40-70 nm-1: 2.5:1.5 (weight ratio); in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 1.8 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nano insulation sleeve M using the nano insulation material M is substantially the same as the process for preparing the detachable turbine nano insulation sleeve M of example 6, except that the nano insulation material is different.

Comparative example 5

A nano heat insulating material n containing hollow ZrO₂77.6 wt.% of fiber, 4.3 wt.% of nano titanium calcium aluminate and 18.1 wt.% of nano ZnO coated potassium hexatitanate whisker, wherein the total weight of the nano thermal insulation material n is taken as a reference.

Wherein the particle size of the nano calcium titanium aluminate is 85 nm; in the nano ZnO coated potassium hexatitanate whisker, the content of nano ZnO is 1.8 wt.%, and the weight of the nano ZnO coated potassium hexatitanate whisker is taken as a reference.

The process for preparing the detachable turbine nano insulation sleeve N using the nano insulation material N is substantially the same as the process for preparing the detachable turbine nano insulation sleeve N of example 6, except that the nano insulation material is different.

Comparative example 6

A nano heat insulating material o containing hollow ZrO₂77.6 wt.% of fiber, 17.8 wt.% of nano calcium titanate aluminate and 4.6 wt.% of nano ZnO coated potassium hexatitanate whisker, based on the total weight of the nano thermal insulation material o.

The process for preparing the removable turbine nano insulation jacket O using the nano insulation material O is substantially the same as the process for preparing the example 6 except that the nano insulation material is different.

Comparative example 7

A nano insulating material p having substantially the same composition as that of the nano insulating material g of example 7 except that: which comprises hollow ZrO₂Fiber 74.0 wt.%, hollow Al₂O₃Nanosphere 17.1 wt.%.

The process for preparing the removable turbine nano insulation jacket P using the nano insulation material P is substantially the same as the process for preparing example 6 except that the nano insulation material is different.

Comparative example 8

A nano insulating material q having substantially the same composition as that of the nano insulating material g of example 7 except that: which comprises hollow ZrO₂Fiber 81.0 wt.%, hollow Al₂O₃Nanosphere 10.1 wt.%.

The process for preparing the detachable turbine nano insulation sleeve Q using the nano insulation material Q is substantially the same as the process for preparing example 6 except that the nano insulation material Q is different.

Comparative example 9

A nano-insulating material r having substantially the same composition as that of the nano-insulating material g of example 7 except that: the nano-ZnO coated potassium hexatitanate whisker comprises 2.8 wt% of nano-titanium calcium aluminate and 6.1 wt% of nano-ZnO coated potassium hexatitanate whisker.

The process for preparing the removable turbine nano insulation cover R using the nano insulation material R is substantially the same as the process for preparing the example 6 except that the nano insulation material is different.

Comparative example 10

A nano-insulating material s having substantially the same composition as that of the nano-insulating material g of example 7 except that: it contains 2.2 wt.% of nano calcium titanate aluminate and 6.7 wt.% of nano ZnO coated potassium hexatitanate whisker.

The process for preparing the removable turbine nano insulation sheath S using the nano insulation material S is substantially the same as that of example 6 except that the nano insulation material is used.

Performance test and test results

The properties, such as compressive strength, bending resistance and thermal conductivity, of the detachable turbine nano heat-insulating sleeves a to S prepared from the nano heat-insulating materials of examples 1 to 89 and comparative examples 1 to 10 were respectively tested, and the test results are shown in table 1.

TABLE 1 Performance test data

From the test results in table 1, the detachable turbine nanometer thermal insulation jacket with high compressive strength, high bending strength and low thermal conductivity can be obtained only by using the nanometer thermal insulation material with the specific composition (i.e. the composition and the content ratio) of the application, and the detachable turbine nanometer thermal insulation jacket has the advantages of excellent thermal insulation performance, long service life, convenient detachment and repeated use, thereby greatly reducing the production cost and the use cost of the turbine nanometer thermal insulation jacket and the energy consumption generated when the turbine nanometer thermal insulation jacket is used for thermal insulation; and significantly extends the useful life of the turbine by making it safe and effective to maintain a high operating efficiency.

Among them, especially comparing the test results of example 7 with those of comparative examples 1 to 6, it can be seen that the present application unexpectedly improves various properties including compressive strength, bending strength, and thermal conductivity by searching and improving the composition and content ratio of the nano-insulation material, especially by combining specific components with content ratio to form the nano-insulation material having a specific composition, thereby further showing that the synergistic effect is generated between the components of the nano-insulation material of the present application, no matter whether the same weight part of hollow ZrO is used singly₂Fibres, or hollow ZrO only₂Fiber and hollow Al₂O₃A combination of both nanospheres, or hollow ZrO₂Fiber, hollow Al₂O₃The combination of the nanospheres and the nano calcium titanium aluminate or nano ZnO coated potassium hexatitanate whiskers cannot generate similar technical effects.

Comparing the examples with comparative examples 7-10, however, it can be shown that the above-mentioned combination of properties can be obtained only by using the nano-insulation material with the specific content ratio of the present application, and the content of any component outside the range defined in the present application can cause significant deterioration of the properties.

Comparing example 7 with examples 8 and 9, it can be shown that the application also for hollow Al in the case of using the nano-insulation material of the specific composition of the application₂O₃The particle size distribution of the nanospheres and the process conditions for preparing the detachable turbine nanometer thermal insulation sleeve by utilizing the nanometer thermal insulation material are beneficially explored, and further, the hollow Al with the specific particle size distribution is found to be adopted₂O₃Nanospheres, as well as specific process conditions, may provide further, unexpected improvements in the aforementioned properties.

Throughout this application, various publications are referenced. The disclosures of these publications in their entireties are hereby incorporated by reference into this application in order to more fully describe the compounds, compositions, and methods described herein.

Various modifications and changes can be made to the compounds, compositions, and methods described herein. Other aspects of the compounds, compositions, and methods described herein will be apparent from consideration of the specification and practice of the compounds, compositions, and methods disclosed herein. It is intended that the specification and examples be considered as exemplary.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. A nano heat-insulating material comprises the following components:

hollow ZrO₂75-80 wt.% of fiber

Hollow Al₂O₃Nanosphere 10-15wt. -%)

3-6 wt.% of nano calcium titanium aluminate

2-6 wt.% of nano ZnO coated potassium hexatitanate whisker

Based on the weight of the nano-insulation material.

2. The nano heat insulating material according to claim 1, wherein the hollow ZrO is formed of a hollow ZrO₂The fiber content is 76.5-78.5 wt.%.

3. The nano heat insulating material according to claim 1, wherein the hollow Al is₂O₃The nanosphere content is 11.5-14.5 wt.%.

4. The nano heat insulating material according to claim 1, wherein the hollow Al is₂O₃The particle size of the nanosphere is 40-130 nm.

5. The nano thermal insulating material according to claim 1, wherein the nano calcium titanoaluminate is present in an amount of 3.5 to 5.5 wt.%.

6. A method for preparing a detachable turbine nanometer heat insulation sleeve comprises the following steps:

1) firstly hollow ZrO₂Uniformly chopping the fiber into short fiber of 0.5-1.5mm, and then cutting the hollow ZrO into pieces₂Fiber, hollow Al₂O₃Uniformly mixing the nanospheres, the nano calcium titanium aluminate and the nano ZnO coated potassium hexatitanate crystal according to the proportion of claim 1;

7. The method for preparing a removable turbine nano insulation sleeve according to claim 6, wherein the solid content of the suspension in the step 2) is 50-75 wt.%.

8. The method for preparing the detachable turbine nanometer thermal insulation sleeve according to claim 6, wherein the drying temperature in the step 4) is 30-90 ℃, and the drying time is 2-10 h.

9. The method for preparing the detachable turbine nanometer thermal insulation sleeve according to claim 6, wherein in the step 5), the temperature is raised to 750-.

10. A detachable turbine nano thermal insulation sleeve manufactured by the manufacturing method of any one of claims 6 to 9.