AU2015285308A1

AU2015285308A1 - Conveyor belt specification determination method

Info

Publication number: AU2015285308A1
Application number: AU2015285308A
Authority: AU
Inventors: De Qing Zou
Original assignee: Yokohama Rubber Co Ltd
Current assignee: Yokohama Rubber Co Ltd
Priority date: 2014-07-03
Filing date: 2015-06-30
Publication date: 2017-02-09
Anticipated expiration: 2035-06-30
Also published as: JP6565677B2; WO2016002782A1; CN106458450A; JPWO2016002782A1; AU2015285308B2; CN106458450B

Abstract

In order to efficiently determine a specification of a upper rubber cover having durability matching use conditions, the horizontal energy (EH) and the vertical energy (EV) received by the conveyor belt (1) by introducing and conveying objects to be conveyed (S) loaded on a upper rubber cover (3) of the conveyor belt (1) are set as indices to categorize the severity of use conditions of the conveyor belt (1) into multiple categories (C1-C5). A use condition database (DB1) is created in advance which, for each of the categories (C1-C5), configures the permissible range of prescribed characteristics of the upper rubber cover, including at least wear resistance and cut resistance. The specification of the upper rubber cover (3) of this conveyor belt (1) is determined on the basis of the use condition database (DB1) and the calculation result of the horizontal energy (EH) and the vertical energy (EV), which are calculated on the basis of the use conditions of the conveyor belt (1).

Description

CONVEYOR BELT SPECIFICATION DETERMINATION METHOD

Technical Field [0001]

The present invention relates to a conveyor belt specification determination method and more specifically relates to a conveyor belt specification determination method capable of efficiently determining a specification of an upper rubber cover having durability matching use conditions.

Background Art [0002]

Various objects, including mineral resources such as iron ore and limestone, are conveyed by a conveyor belt. When the objects are conveyed by the conveyor belt, the objects to be conveyed are fed onto an upper rubber cover of the conveyor belt from a hopper or another conveyor belt. The fed objects to be conveyed are carried on the upper rubber cover and conveyed in a traveling direction of the conveyor belt. When the objects to be conveyed are fed onto the upper rubber cover of the conveyor belt, the upper rubber cover is subject to impact, and when the surfaces of the objects to be conveyed are sharp, the upper rubber cover sometimes sustains cut damage. When the objects to be conveyed are loaded on the upper rubber cover and conveyed, the upper rubber cover is subject to wear as a result of the objects to be conveyed sliding on the upper rubber cover. Thus, in known art, various proposals have been made (see Patent Documents 1 and 2 for example) in order to improve the cut resistance of the upper rubber cover, or to improve the wear resistance of the upper rubber cover.

[0003] A size and occurrence frequency of the cut damage, a wear amount, and the like occurring in the upper rubber cover significantly change depending on use conditions of the conveyor belt, types of the objects to be conveyed and the like.

Thus, upon determining a specification of the conveyor belt (a specification of the upper rubber cover, for example), it has been necessary to determine the specification in each individual case, namely to determine a specific specification, on the basis of the use conditions and the type of the objects to be conveyed and the like, which has been a problem in that it requires a great number of man-hours.

Citation List Patent Literature [0004] 1

Patent Document 1: Japanese Unexamined Patent Application Publication No. 2001-88922A

Patent Document 2: Japanese Unexamined Patent Application Publication No. 2014-40295A

Summary of Invention Technical Problem [0005]

An object of the present invention is to provide a conveyor belt specification determination method capable of efficiently determining a specification of an upper rubber cover having durability matching use conditions.

Summary of Invention [0006] A conveyor belt specification determination method of the present invention to achieve the above-described object includes the steps of: categorizing, into a plurality of categories, a severity of use conditions of a conveyor belt, using a horizontal energy and a vertical energy as indices, the horizontal energy and vertical energy being received by the conveyor belt as a result of objects to be conveyed being fed onto and loaded on an upper rubber cover of the conveyor belt and conveyed, and creating, in advance, a use condition database, in which a permissible range of each of prescribed characteristics is set for each of the categories, the prescribed characteristics including at least wear resistance and cut resistance of the upper rubber cover; and calculating, when determining a specification of the conveyor belt, the horizontal energy and the vertical energy on the basis of the use conditions of the conveyor belt, and determining a specification of the upper rubber cover of the conveyor belt on the basis of the calculation results and the use condition database.

Advantageous Effects of Invention [0007]

The horizontal energy that is received by the conveyor belt when the objects to be conveyed are fed onto and conveyed while being loaded on the conveyor belt mainly has a large impact on a wear amount of the upper rubber cover. The vertical energy mainly has a large impact on the size and occurrence frequency of cut damage of the upper rubber cover. Thus, according to the present invention in which the severity of the use conditions of the conveyor belt is categorized into the plurality of categories while using the horizontal energy and vertical energy as indices, representative use conditions are easily sorted in an appropriate manner. Therefore, 2 by using the horizontal energy and the vertical energy calculated on the basis of the use conditions of this conveyor belt (the calculation results) and the use condition database, the specification of the upper rubber cover provided with appropriate durability with respect to the use conditions can be efficiently determined.

[0008]

Here, the severity of the use conditions of the conveyor belt is categorized into at least five categories, for example. By categorizing the severity into the at least five categories, most of the actual use conditions of the conveyor belt can be covered.

[0009]

Evaluation methods for the prescribed characteristics may also be set for each of the categories in accordance with a property of each of the characteristics. When the severity categories are different, rather than using the same evaluation method for a specific characteristic of the upper rubber cover, using a different evaluation method of that characteristic depending on the category may result in conforming to actual results. Therefore, in that kind of case, when evaluating the characteristics of the upper rubber cover, different evaluation methods are preferably used for each of the categories.

[0010]

The use condition database may be created in advance for each of the types of the objects to be conveyed. Depending on the type of the objects to be conveyed, differences arise in a degree of damage and a degree of wear imparted to the upper rubber cover. Thus, if the use condition database is created in advance for each of the types of the objects to be conveyed, the specification of the upper rubber cover provided with the durability more closely matching the use conditions of the conveyor belt can be determined.

[0011]

An external environment database may be created in advance in which, with respect to at least one of prescribed required characteristics of the upper rubber cover attributable to an external environment of the conveyor belt, a plurality of stages of a permissible range are set representing differing degrees of requirement for the prescribed required characteristic. When determining the specification of the conveyor belt, the specification of the upper rubber cover of the conveyor belt may be determined on the basis of the external environment in which the conveyor belt is used and the external environment database, as well as on the basis of the calculation results of the horizontal energy and the vertical energy and the use condition database. The durability of the upper rubber cover is influenced not only by the use conditions of the conveyor belt, but also by the external environment of the conveyor belt. This method is advantageous in determining the specification of the upper rubber cover 3 having the durability matching the use conditions and the external environment of the conveyor belt.

[0012]

Such prescribed required characteristics can include weather resistance, heat resistance, low-temperature resistance, oil resistance, chemical resistance, flame retardancy, conductivity and the like. By taking into account these prescribed required characteristics, representative external environments of the conveyor belt can mostly be covered.

[0013]

Then, when determining the specification of the conveyor belt, an extending direction energy received by the conveyor belt may be calculated, while taking into account an inclination angle of an extending direction of the conveyor belt with respect to the horizontal, on the basis of the inclination angle and the horizontal energy, and the calculated extending direction energy may be used as the horizontal energy. When the conveyor belt is installed such that the extending direction of the conveyor belt is inclined with respect to the horizontal, the severity of the use conditions is more appropriately evaluated by using the extending direction energy of the conveyor belt as an index rather than using the horizontal energy that is received by the conveyor belt conveying the loaded objects to be conveyed as the index. This method is even more advantageous in determining the specification of the upper rubber cover having the durability matching the actual use conditions of the conveyor belt.

Brief Description of Drawings [0014] FIG. 1 is an explanatory view illustrating a conveyor belt line in a simplified manner. FIG. 2 is a cross-sectional view taken along A-A of FIG. 1. FIG. 3 is an explanatory view illustrating a state of horizontal energy and vertical energy received by the conveyor belt. FIG. 4 is an explanatory view illustrating categorized categories. FIG. 5 is an explanatory view illustrating a configuration of a use condition database. FIG. 6 is an explanatory view illustrating a state of conveyor-belt extending direction energy, horizontal energy, and vertical energy received by the inclined conveyor belt. FIG. 7 is an explanatory view illustrating a configuration of an external environment database. 4 FIG 8 is an explanatory view illustrating steps for determining a specification of an upper rubber cover.

Description of Embodiment [0015] A conveyor belt specification determination method of the present invention will be described below on the basis of an embodiment illustrated in the drawings.

[0016]

In a conveyor belt line illustrated in FIG 1, objects to be conveyed S conveyed by another conveyor belt 7 are fed onto a conveyor belt 1 and conveyed to a conveying destination by this conveyor belt 1. The objects to be conveyed S may be fed onto the conveyor belt 1 by a hopper and the like. The conveyor belt 1 is stretched at a prescribed tension between pulleys 5a and 5b.

[0017]

As illustrated in FIG 2, the conveyor belt 1 is configured by a core layer 2 formed of a core, such as canvas or steel cords, and an upper rubber cover 3 and a lower rubber cover 4 that sandwich the core layer 2 therebetween. The core layer 2 is a member bearing the tension that causes the conveyor belt 1 to be stretched. The lower rubber cover 4 is supported by a support roller 6 on a carrier side of the conveyor belt 1, and the upper rubber cover 3 is supported by the support roller 6 on a return side of the conveyor belt 1. Three of the support rollers 6 are arranged on the carrier side of the conveyor belt 1 in the belt width direction. The conveyor belt 1 is supported by these support rollers 6 in a concave shape having a prescribed trough angle a. When the pulley 5 a on a drive side is rotationally driven, the conveyor belt 1 is operated in one direction at a prescribed traveling speed VI. The objects to be conveyed S are fed onto the upper rubber cover 3, and are loaded on the upper rubber cover 3 and conveyed.

[0018]

In this conveyor belt line, as illustrated in FIG. 3, the horizontally-installed conveyor belt 1 and the horizontally-installed other conveyor belt 7 are arranged so as to have a vertical difference h therebetween (the difference h between height positions of respective conveying surfaces of the conveyor belts 1 and 7). On the other conveyor belt 7, the objects to be conveyed S are conveyed at a horizontal direction speed V0, while a vertical direction speed is zero. At the moment at which the objects to be conveyed S are fed toward the conveyor belt 1 from the other conveyor belt 7, the objects to be conveyed S with a mass m have a kinetic energy of (m * VO2)

/ 2. Further, when a position of the conveying surface of the conveyor belt 1 at this point in time is used as a reference, a potential energy of the objects to be conveyed S 5 with the mass m is mgh, where g is gravitational acceleration. Thus, an energy EO of the objects to be conveyed S with the mass m at this point in time is expressed by the following Formula (1). E0 = (m* VO2)/2 +mgh ··· (1) [0019]

When the objects to be conveyed S are loaded on the conveyor belt 1, the horizontal direction speed remains at VO, and the vertical direction speed becomes zero. Then, the objects to be conveyed S are loaded on and conveyed by the conveyor belt 1. The objects to be conveyed S are conveyed in the horizontal direction at the traveling speed VI of the conveyor belt 1. The traveling speed VI is faster than the horizontal direction speed VO (VI > VO). At a timing at which a state is obtained in which the objects to be conveyed S having the mass m are conveyed at the traveling speed VI, the energy of the objects to be conveyed S is a kinetic energy of (m * VI2) / 2, and there is no change in the potential energy thereof. Thus, at the timing at which the state is obtained in which the objects to be conveyed S having the mass m are conveyed at the traveling speed VI, an energy El of the objects to be conveyed S is expressed by the following Formula (2).

El = (m * VI2) / 2 ··· (2) [0020]

Thus, of an energy E received by the conveyor belt 1 as a result of the objects to be conveyed S with the mass m being fed onto the upper rubber cover 3 of the conveyor belt 1 and being loaded and conveyed, a horizontal energy Eh (a horizontal component) is expressed by the following Formula (3). Further, of the energy E, a vertical energy Ev (a vertical component) is expressed by the following Formula (4). Eh = (m * VI2) / 2 - (m * VO2) / 2 - (3)

Ev = mgh ··· (4) [0021]

When Eh and Ev are respectively converted into a horizontal energy EH and a vertical energy EV received by a unit area of the conveyor belt 1 during an operation time, EH and EV are expressed by the following Formulas (5) and (6). EH = Μ * (VI2 - VO2) * t/2 /(W * L) / 1000 - (5) EV = Mgh * t /(W * L) / 1000 - (6)

Here, M is a conveying weight per unit time (kg/h), g is the gravitational acceleration (9.8 m/s2), VI is the belt traveling speed (m/s), V0 is the initial horizontal 6 direction speed of the objects to be conveyed (m/s), W is an effective width of the belt (m), L is a belt length (m), and t is a belt operation time (h). Note that the effective width W of the belt is 60% to 80% of the width dimension of the conveyor belt 1, for example, and is empirically set as a range over which the objects to be conveyed S are loaded.

[0022]

As illustrated in FIG. 4, in the present invention, while using the horizontal energy EH and the vertical energy EV as indices, the severity of use conditions of the conveyor belt 1 is categorized into a plurality of categories Cl to C5. In FIG. 4, the horizontal energy EH is the horizontal axis and the vertical energy EV is the vertical axis, while the severity is categorized into the five categories Cl to C5.

[0023]

The first category Cl is a category in which the horizontal energy EH and the vertical energy EV are relatively small-scale. The second category C2 is a category in which the horizontal energy EH is relatively medium-scale and the vertical energy EV is relatively small-scale. The third category C3 is a category in which the horizontal energy EH is relatively small-scale and the vertical energy EV is relatively medium-scale. The fourth category C4 is a category in which the horizontal energy EH and the vertical energy EV are relatively medium-scale. The fifth category C5 is a category in which the horizontal energy EH and the vertical energy EV are relatively large-scale.

[0024]

The number of categories is not limited to five, but may be three or four categories, or may be six or more categories. However, when the number of categories becomes excessively large, data analysis and the like become complex. Thus, the number of categories preferably has an upper limit of around ten. By categorizing the severity into the at least five categories, the actual use conditions of the conveyor belt 1 can be substantially covered. As described above, by acquiring data of prescribed characteristics, including wear resistance and cut resistance, with respect to the conveyor belt 1 adopting various use conditions and specifications of the upper rubber cover 3, an appropriate permissible range in actual use, is ascertained for each of the characteristics.

[0025]

Next, as illustrated in FIG 5, a use condition database DB1 is created in advance in which permissible ranges are set for the prescribed characteristics of the upper rubber cover 3, including at least the wear resistance and the cut resistance, for each of the categories Cl to C5. The use condition database DB1 is input into and stored in a computation device 8, such as a personal computer. 7 [0026]

For example, a test method is specified for the wear resistance, and an appropriate permissible range in terms of practical use is set for those categories. Specific examples of the test method include a DIN abrasion test, a Lamboum abrasion test, a Pico abrasion test, an Akron abrasion test, and the like. Permissible ranges of a wear amount identified using this type of specific wear test are set.

[0027] A test method is also specified for the cut resistance in the same manner, and an appropriate permissible range in terms of practical use is set for those categories. Specific examples of the text method include a test method in which a blade of a prescribed specification (shape and weight) is dropped from a prescribed height, and the like. Permissible ranges of a cut depth identified using this type of cut resistance test are set.

[0028]

As the prescribed characteristics of the upper rubber cover, necessary characteristics may be incorporated as appropriate, in addition to the wear resistance and the cut resistance. For example, chipping resistance may be incorporated. A test method is also specified for the chipping resistance in the same manner, and an appropriate permissible range in terms of practical use is set for each of the categories.

[0029]

When determining a new specification of the conveyor belt 1, the horizontal energy EH and the vertical energy EV are calculated on the basis of the use conditions of the conveyor belt 1. Next, on the basis of the calculated horizontal energy EH and vertical energy EV, and the use condition database DB1 created in advance, a specification (a rubber type, a thickness, and the like) of the upper rubber cover 3 of the conveyor belt 1 is determined.

[0030]

Specifically, the calculated horizontal energy EH and the vertical energy EV are input into the computation device 8, and on the basis of the input calculated results, it is determined which of the categories stored in the use condition database DB1 applies to the conveyor belt 1. After the category is determined, the specification of the upper rubber cover 3 is determined within the permissible ranges of the prescribed characteristics, including the wear resistance and the cut resistance, set for that category.

[0031]

According to the present invention, the horizontal energy EH and the vertical energy EV received by the conveyor belt 1 when the objects to be conveyed S are fed, loaded and conveyed are set as indices to categorize the severity of use conditions of 8 the conveyor belt 1 into the plurality of categories Cl to C5. The horizontal energy EH mainly has a significant influence on the wear amount of the upper rubber cover 3, and the vertical energy EV mainly has a significant influence on the size and occurrence frequency of the cut damage of the upper rubber cover 3. Thus, representative use conditions are easily sorted in an appropriate manner. Therefore, by using the use condition database DB1 and the horizontal energy EH and the vertical energy EV calculated on the basis of the use conditions of the conveyor belt 1, the specification of the upper rubber cover 3 provided with an appropriate durability with respect to the use conditions can be efficiently determined without expending a large amount of labor.

[0032]

Evaluation methods for the prescribed characteristics, such as the wear resistance and the cut resistance, can also be set for each of the categories in accordance with properties of the characteristics. When the severity categories are different, rather than using the same evaluation method for a specific characteristic of the upper rubber cover 3, using a different evaluation method of that characteristic depending on the category may result in conforming to actual results. Therefore, in that kind of case, when evaluating the characteristics of the upper rubber cover 3, different evaluation methods are preferably used for each of the categories.

[0033]

Depending on the type of the objects to be conveyed S, for example, on whether it is iron ore, limestone, gravel, or the like, the hardness, sharpness, and the like of the objects differ. Thus, differences arise in a degree of damage and a degree of wear imparted to the upper rubber cover 3. Thus, if the use condition database DB 1 is created in advance for each type of the objects to be conveyed S, the specification of the upper rubber cover 3 provided with the durability more closely matching the use conditions of the conveyor belt 1 can be determined.

[0034]

In the above-described embodiment, the conveyor belt 1 is installed so as to extend horizontally. However, as illustrated in FIG. 6, in some cases, the conveyor belt 1 is installed with an extending direction thereof inclined at an inclination angle a with respect to the horizontal. A case will be considered in which the conveyor belt 1 is installed so as to be inclined in the above-described manner, and the objects to be conveyed S are fed onto the conveyor belt 1 from the other conveyor belt 7, namely, fed from the height of the vertical difference h.

[0035]

On the other conveyor belt 7, the objects to be conveyed S are conveyed at the horizontal direction speed V0 while the vertical direction speed is zero. At the 9 moment at which the objects to be conveyed S are fed toward the conveyor belt 1 from the other conveyor belt 7, the objects to be conveyed S with the mass m have the kinetic energy of (m * VO2) / 2. Further, when the position of the conveying surface of the conveyor belt 1 at this point in time is used as a reference, the potential energy of the objects to be conveyed S with the mass m is mgh, where g is the gravitational acceleration. Thus, the energy EO of the objects to be conveyed S with the mass m at this point in time is expressed by the following Formula (7). Specifically, Formula (7) is equivalent to Formula (1). EO = (m * VO2) / 2 + mgh - (7) [0036]

When the objects to be conveyed S are loaded on the conveyor belt 1, the horizontal direction speed remains at VO, and the vertical direction speed becomes zero. Then, the objects to be conveyed S are loaded on and conveyed by the conveyor belt 1. The objects to be conveyed S are conveyed at the traveling speed VI of the conveyor belt 1 in a direction inclined at the inclination angle a with respect to the horizontal direction. The traveling speed VI is faster than the horizontal direction speed VO (VI > VO). At the timing at which the state is obtained in which the objects to be conveyed S with the mass m are conveyed at the traveling speed VI, the energy of the objects to be conveyed S is the kinetic energy of (m * VI2) / 2. The potential energy also changes and becomes mgH, when using a position at which the objects to be conveyed S are placed on the conveyor belt 1 as a reference. Thus, at the timing at which the state is obtained in which the objects to be conveyed S with the mass m are conveyed at the traveling speed VI, an energy E2 of the objects to be conveyed S is expressed by the following Formula (8). E2 = (m * VI2) / 2 ± mgH - (8)

The potential energy becomes + mgH when the traveling direction of the conveyor belt 1 is inclined diagonally upward, and the potential energy becomes -mgH when the traveling direction of the conveyor belt 1 is inclined diagonally downward.

[0037]

Thus, of the energy E received by the conveyor belt 1 as a result of the objects to be conveyed S with the mass m being fed onto the upper rubber cover 3 of the conveyor belt 1 and being loaded and conveyed, an extending direction energy El of the conveyor belt 1 is expressed by the following Formula (9). Further, of the energy E, a vertical energy Ev is expressed by the following Formula (10).

El = (m * VI2) / 2 - (m * VO2) / 2 ± mgH = m(Vl2 - VO2) / 2 ± m(Vlsina)2 / 2 - (9) 10 Εν = mgh ··· (10) [0038]

When El and Ev are respectively converted into an extending direction energy EL and the vertical energy EV received by the unit area of the conveyor belt 1 during the operation time, EL and EV are expressed by the following Formulas (11) and (12). EL = M *(V12 - VO2 ± (Vlsina)2) * t / 2 / (W * L) / 1000 - (11) EV = Mgh * t /(W * L) /1000 - (12)

Here, M is the conveying weight per unit time (kg/h), g is the gravitational acceleration (9.8 m/s2), VI is the belt traveling speed (m/s), V0 is the initial horizontal direction speed of the objects to be conveyed (m/s), W is the effective width of the belt (m), L is the belt length (m), and t is the belt operation time (h). Note that the effective width of the belt is 60% to 80% of the width dimension of the conveyor belt 1, for example, and is empirically set as the range over which the objects to be conveyed S are loaded.

[0039]

Although when the conveyor belt 1 is installed at the inclination angle a, the vertical energy EV is the same as in the case when the conveyor belt 1 is installed horizontally, the extending direction energy EL is preferably used instead of the horizontal energy EH. Then, as illustrated in FIG 4, the severity of the use conditions of the conveyor belt 1 is preferably categorized into the plurality of categories Cl to C5, while using the vertical energy EV and the horizontal energy EH, which takes into account the inclination angle a, as indices.

[0040]

Then, when determining the specification of the conveyor belt 1 installed so as to be inclined in the above-described manner, the extending direction energy EL received by the conveyor belt 1 is preferably calculated taking into account the inclination angle a of the extending direction of the conveyor belt 1 with respect to the horizontal, on the basis of the inclination angle a and the horizontal energy EH, and the calculated extending direction energy EL is preferably used in place of the horizontal energy EH used in the case when the conveyor belt 1 is installed horizontally. As a result, even more advantages are gained when determining the specification of the upper rubber cover 3 provided with the durability matching the actual usage of the conveyor belt 1 installed so as to be inclined.

[0041]

Incidentally, when analyzing the conveyor belt 1 to be actually used in more detail, the size and occurrence frequency of the cut damage occurring in the upper 11 rubber cover 3, the wear amount thereof and the like change depending on the external environment, even when the use conditions of the conveyor belt 1 are the same. For example, depending on whether the conveyor belt 1 is used outdoors or indoors, a degree of weather resistance required for the upper rubber cover 3 differs. Alternatively, depending on whether the conveyor belt 1 conveys the high-temperature objects to be conveyed S or the room-temperature objects to be conveyed S, a degree of heat resistance required for the upper rubber cover 3 differs.

[0042]

Such prescribed required characteristics of the upper rubber cover 3 include low-temperature resistance, oil resistance, chemical resistance, flame retardancy, conductivity and the like, for example, in addition to weather resistance and heat resistance. When the objects to be conveyed S contain a lot of oil, oil resistance is required for the upper rubber cover 3, and when the objects to be conveyed S are highly flammable, the upper rubber cover 3 is required to have high flame retardancy and low conductivity.

[0043]

Then, each of the required characteristics has related characteristic indices. Since the strength of ultraviolet light has an impact on the weather resistance, the strength of the ultraviolet light becomes a characteristic index. Further, since the level of ozone concentration also has an impact on the weather resistance, the ozone concentration also becomes a characteristic index. With respect to the oil resistance, since swelling characteristics due to the oil attached to the upper rubber cover 3 have an impact thereupon, for example, they become a characteristic index. The required characteristics and their characteristic indices can be illustrated in Table 1. Note that low-swelling oil, medium-swelling oil, and high-swelling oil described in Table 1 respectively correspond to ASTM No.l oil, IRM902, and IRM903.

[0044]

[TABLE 1] REQUIRED CHARACTERISTIC CHARACTERISTIC INDEX PERMISSIBLE RANGE WEATHER RESISTANCE STRENGTH OF ULTRAVIOLET LIGHT WEAK MEDIUM STRONG OZONE CONCENTRATION LOW MEDIUM HIGH 12 HEAT RESISTANCE AMBIENT TEMPERATURE (°C) 60 OR HIGHER AND LOWER THAN 100 100 OR HIGHER AND LOWER THAN 200 200 OR HIGHER LOW TEMPERATURE RESISTANCE AMBIENT TEMPERATURE (°C) MINUS 60 OR HIGHER AND LOWER THAN 40 MINUS 40 OR HIGHER AND LOWER THAN 20 MINUS 20 OR HIGHER AND LOWER ΤΗΑΝ0 OIL RESISTANCE SWELLING PROPERTIES LOW SWELLING OIL MEDIUM SWELLING OIL HIGH SWELLING OIL CHEMICAL RESISTANCE pH VALUE <7 7 >7 FLAME RETARDANCY FLAME RETARDANCY LEVEL 1 2 3 CONDUCTIVITY VOLUME RESISTIVITY (Ω) LESS THAN 3x 108 3 x 108 OR GREATER - [0045]

Here, an external environment database DB2 is preferably created in advance, in which a plurality of levels of permissible ranges are set for the prescribed required characteristics of the upper rubber cover 3 that are attributable to the external environment of the conveyor belt 1, the levels representing differing degrees of requirement for each of those prescribed required characteristics. Then, when determining the specification of the conveyor belt 1, the specification of the upper rubber cover 3 of the conveyor belt 1 is determined on the basis of the external environment in which the conveyor belt 1 is used and the external environment database DB2, as well as on the above-described calculation results of the horizontal energy EH and the vertical energy HV and the use condition database DB1.

[0046]

As illustrated in FIG. 7, in the external environment database DB2, the permissible ranges of the characteristic indices related to each of required characteristics R1 to R7 are set for each of the required characteristics R1 to R7 of the 13 upper rubber cover 3. The external environment database DB2 is input into and stored in the computation device 8, which is a personal computer or the like. One required characteristic may have a plurality of characteristic indices or a single characteristic index.

[0047]

Specifically, as illustrated in FIG. 8, when determining the specification of the conveyor belt 1, numerical values corresponding to each of the required characteristics R1 to R7 (the characteristic indices) are input into the computation device 8 with respect to the external environment in which the conveyor belt is used. On the basis of the input numerical values, it is determined which of the permissible ranges stored in the external environment database DB2 applies to the degree of requirement of each of the required characteristics R1 to R7 of the upper rubber cover 3 of the conveyor belt 1. Then, a type of rubber that is within the permissible ranges determined for each of the required characteristics R1 to R7 calculated from the external environment database DB2 is selected as the upper rubber cover 3.

[0048]

Next, as described above, the horizontal energy EH and the vertical energy EV that are calculated on the basis of the use conditions of the conveyor belt 1 are input into the computation device 8, and on the basis of the input calculated results, it is determined which of the categories stored in the use condition database DB1 applies to the conveyor belt 1. After the category is determined, the specification of the upper rubber cover 3 is determined within the permissible ranges of the prescribed characteristics, including the wear resistance and the cut resistance, set for that category, and from the types of rubber determined using the external environment database DB2.

[0049]

The present embodiment is advantageous in determining the specification of the upper rubber cover 3 provided with the durability matching the use conditions and the external environment of the conveyor belt 1. Further, by taking into account the weather resistance, heat resistance, low-temperature resistance, oil resistance, chemical resistance, flame retardancy, and conductivity as the prescribed required characteristics R1 to R7, representative external environments of the conveyor belt 1 can be substantially covered.

Reference Signs List [0050] 1 Conveyor belt 2 Core layer 14 3 Upper rubber cover 4 Lower rubber cover 5 a, 5b Pulley 6 Support roller 7 Other conveyor belt 8 Computation device Cl to C5 Category R1 to R7 Required characteristics DB1 Use condition database DB2 External environment database S Objects to be conveyed 15

Claims

Claims [Claim 1] A conveyor belt specification determination method comprising the steps of: categorizing, into a plurality of categories, a severity of use conditions of a conveyor belt, using a horizontal energy and a vertical energy as indices, the horizontal energy and vertical energy being received by the conveyor belt as a result of objects to be conveyed being fed onto and loaded on an upper rubber cover of the conveyor belt and conveyed; creating, in advance, a use condition database, in which a permissible range of each of prescribed characteristics is set for each of the categories, the prescribed characteristics including at least wear resistance and cut resistance of the upper rubber cover; calculating, when determining a specification of the conveyor belt, the horizontal energy and the vertical energy on the basis of the use conditions of the conveyor belt; and determining a specification of the upper rubber cover of the conveyor belt on the basis of the calculation results and the use condition database. [Claim
2] The conveyor belt specification determination method according to claim 1, wherein the severity of the use conditions of the conveyor belt is categorized into at least five categories. [Claim
3] The conveyor belt specification determination method according to claim 1 or 2, wherein an evaluation method of the prescribed characteristic is set in accordance with a property of the prescribed characteristic for each of the categories. [Claim
4] The conveyor belt specification determination method according to any one of claims 1 to 3, wherein the use condition database is created in advance for each of types of the objects to be conveyed. [Claim
5] The conveyor belt specification determination method according to any one of claims 1 to 4, wherein an external environment database is created in advance in which, with respect to at least one of prescribed required characteristics of the upper rubber cover attributable to an external environment of the conveyor belt, a plurality of stages of a permissible range are set representing differing degrees of requirement for the prescribed required characteristic, and, when determining the specification of the conveyor belt, the specification of the upper rubber cover of the conveyor belt is determined on the basis of the external environment in which the conveyor belt is used and the external environment database as well as on the basis of the calculation results of the horizontal energy and the vertical energy and the use condition database. [Claim
6] The conveyor belt specification determination method according to claim 5, wherein weather resistance, heat resistance, low-temperature resistance, oil resistance, chemical resistance, flame retardancy, and conductivity are included in the prescribed required characteristics. [Claim
7] The conveyor belt specification determination method according to any one of claims 1 to 6, wherein, when determining the specification of the conveyor belt, an extending direction energy received by the conveyor belt is calculated, while taking into account an inclination angle of an extending direction of the conveyor belt with respect to the horizontal, on the basis of the inclination angle and the horizontal energy, and the calculated extending direction energy is used as the horizontal energy.