Field of the invention

The invention relates to a thermocouple unit as defined in independent claim 1.

The invention relates also to device for measuring temperature in a rotary kiln as defined in independent claim 9 and a thermocouple unit for use in the device as defined in claim 22.

A quick responding temperature measurement is required for the determination of temperatures prevailing within the bulk material and within the gas phase of a rotating kiln. The measurement has to be quick responding because of the frequent temperature changes between bulk material and gas phase during rotation of the kiln. These quick responding thermocouples are used without protection to achieve the quick response to temperature changes, which leads to a very short service life of these unprotected thermocouples.

Publication WO 2019/042668 presents a device for measuring the temperature in a rotary kiln through which solid material passes while being heated to elevated temperatures. Said device features a drive as well as an elongated hollow body with means to fix a thermocouple, whereby the drive and the elongated hollow body are mounted such that they rotate jointly with the rotary kiln. The drive can move the elongated hollow body together with thermocouple through an opening in and out of the rotary kiln interior for measuring the temperature inside the rotary kiln during operation. One problem with thermocouples is that thermocouples have a low durability and a limited service life and this means that the thermocouple that is in use must frequently be replaced with a new thermocouple. To solve this problem, one embodiment of the device presented in publication WO 2019/042668 has a magazine for thermocouples that is configured to automatically replace a damaged thermocouple with a new thermocouple from the magazine. This solution to the problem requires however sophisticated mechanical and electrical parts to operate the magazine.

Objective of the invention

The object of the invention is to provide a device for measuring temperature in a rotary kiln having a technically simple arrangement for replacing used and damaged thermocouples with new thermocouples and to provide a thermocouple unit for use in the device and additionally to provide a thermocouple unit.

Short description of the invention

The thermocouple unit is characterized by the definitions of independent claim 1.

Preferred embodiments of the thermocouple unit are defined in claims 2 to 8.

The device for measuring temperature in a rotary kiln of the invention is characterized by the definitions of independent claim 9. Preferred embodiments of the device are defined in the dependent claims 10 to 21.

The thermocouple unit for use in the device is defined in claim 22.

Preferred embodiments of the thermocouple unit for use in the device are defined in claims 23 to 27.

When the thermocouple unit is arranged in a guide pipe configured to receive and movably hold the thermocouple unit, the thermocouple in the bundle of parallel thermocouples with the longest longitudinal extension will first protrude out of the guide pipe when the bundle of parallel thermocouples is moved with the thermocouple drive in the guide pipe with respect to the guide pipe and temperature can be measured with the thermocouple with the longest longitudinal extension. When thermocouple in the bundle of parallel thermocouples with the longest longitudinal extension has worn out, the bundle of parallel thermocouples is moved further in the guide pipe with the thermocouple drive with respect to the guide pipe so that the thermocouple with the second longest longitudinal extension will protrude out of the guide pipe and temperature can be measured with the thermocouple having the second longest longitudinal extension. When the thermocouple with the second longest longitudinal extension has worn out, the thermocouple unit is moved even more with the thermocouple drive in the guide pipe with respect to the guide pipe so that the thermocouple with the third longest longitudinal extension will protrude out of the guide pipe and temperature can be measured with the thermocouple having the third longest longitudinal extension. This will be done until all thermocouples in the bundle of parallel thermocouples have been used and worn out and after that the thermocouple unit comprising a bundle of parallel thermocouples is replaced with a new thermocouple unit comprising of a bundle of parallel thermocouples.

List of figures

In the following the invention will described in more detail by referring to the figures, of which

Figure 1 shows an embodiment of a device for measuring temperature in a rotary kiln,

Figure 2 shows another embodiment of a device for measuring temperature in a rotary kiln,

Figure 3 shows in partly cut view the embodiment of a device for measuring temperature in a rotary kiln illustrated in figure 1,

Figure 4 shows in partly cut view the embodiment of a device for measuring temperature in a rotary kiln illustrated in figure 2,

Figure 5 shows some parts of the device illustrated in figure 1,

Figure 6 shows some parts of the device illustrated in figure 2,

Figure 7 shows the parts illustrated in figure 6 as seen from one end,

Figure 8 shows in partly cut view the embodiment of a device for measuring temperature in a rotary kiln illustrated in figure 1,

Figure 9 shows in partly cut view the embodiment of a device for measuring temperature in a rotary kiln illustrated in figure 2,

Figure 10 is a cross-section view at section E-E in figure 8,

Figure 11 is a cross-section view at section F-F in figure 8,

Figure 12 shows in cut view a rotary kiln having a device for measuring temperature in the rotary kiln interior of the rotary kiln mounted on an outer surface of the rotary kiln and so that only selected parts of the device are shown,

Figure 13 is a view at G-G in figure 12,

Figure 14 shows in cut view a rotary kiln having a device for measuring temperature in the rotary kiln interior of the rotary kiln mounted on an outer surface of the rotary kiln and so that only selected parts of the device are shown, and

Figure 15 is a view at H-H in figure 14.

Detailed description of the invention

First the thermocouple unit 8 and some variants and embodiments of the thermocouple unit 8 will be presented in greater detail.

The thermocouple unit 8 comprises a bundle of parallel thermocouples 14 each having a temperature sensitive tip 15.

Each thermocouple 14 in the bundle of parallel thermocouples is selectively functionally connectable to a temperature determining device 12 by a contact means 13. It is possible that the contact means 13 is physically connected to each thermocouple 14 in the bundle of parallel thermocouples so that the contact means 13 allows a functional connection with any thermocouple 14 in the bundle of parallel thermocouples.

Each thermocouple 14 in the bundle of parallel thermocouples has a longitudinal extension that is different from the longitudinal extension of the other thermocouples 14 in the bundle of parallel thermocouples so that the temperature sensitive tip 15 of each thermocouple 14 in the bundle of parallel thermocouples is in a longitudinal direction A of the bundle of parallel thermocouples located at a different location than the temperature sensitive tip 15 of the other thermocouples 14 in the bundle of parallel thermocouples.

All thermocouples 14 in the bundle of parallel thermocouples can, as illustrated in figures 8 and 9, have different lengths. In such thermocouple unit 8, each thermocouple 14 in the bundle of parallel thermocouples has a distal end 16 at the temperature sensitive tip 15 and an opposite proximal end 17, and the thermocouples 14 in the bundle of parallel thermocouples are arranged so that the proximal end 17 of each thermocouple 14 in the bundle of parallel thermocouples is in the longitudinal direction A of the bundle of parallel thermocouples located at essentially the same location. The result of this will be that the temperature sensitive tip 15 at the distal end 16 of each thermocouple 14 in the bundle of parallel thermocouples will in the longitudinal direction A of the bundle of parallel thermocouples be located at a different location than the temperature sensitive tip 15 of the other thermocouples 14 in the bundle of parallel thermocouples The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, arranged in a row 21 and in order by length as illustrated in figures 8 and 9.

The thermocouples 14 in the bundle of parallel thermocouples can alternatively be arranged in a row 21 and in order by length so that the length of each thermocouple 14 in the bundle of parallel thermocouples is defined by the distance C between a midpoint 22 of the bundle of parallel thermocouples and the temperature sensitive tip 15. It is for example possible that all thermocouples 14 in the bundle of parallel thermocouples have the same length and that the thermocouples 14 in the bundle of parallel thermocouples are arranged so that the opposite ends, i.e. the distal ends 16 and the proximal ends 17, of the thermocouples 14 in the bundle of parallel thermocouples are not located at the same location in the longitudinal direction A of the bundle of parallel thermocouples.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, connected together so that the thermocouples 14 are at least partly spaced from one another so that the thermocouples 14 in the bundle of parallel thermocouples does not disturb each other.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, connected together by a connecting part 18 so that the thermocouples 14 are at least partly spaced from one another so that the thermocouples 14 in the bundle of parallel thermocouples does not disturb each other.

The thermocouple unit 8 comprise preferably, but not necessarily, a guide means 19 configured to guide the bundle of parallel thermocouples in a guide pipe 7 configured to releasable and movable receive the thermocouple unit 8.

The bundle of parallel thermocouples is preferably, but not necessarily, releasable and movable arranged in a guide pipe 7 so that the temperature sensitive tip 15 of each thermocouple 14 in the bundle of parallel thermocouples can protrude out of the guide pipe 7, and the thermocouple unit 8 comprise preferably, but not necessarily, a guide means 19 configured to guide the bundle of parallel thermocouples in the guide pipe 7.

The thermocouple unit 8 comprise preferably, but not necessarily, a contact means 13 comprising a plug means 20 For connecting the thermocouple unit 8 to the temperature determining device 12

Next the device 1 for measuring temperature in a rotary kiln 2 having a rotating shell structure 3 limiting a rotary kiln interior 4 and some embodiments thereof will be described in greater detail. The rotating shell structure 3 can include a refractory lining (not marked with a reference numeral) as illustrated in the figures.

The device 1 has a frame 5 for mounting the device at an outer surface 6 of the rotating shell structure 3 of the rotary kiln 2 so that the device 1 rotates jointly with the rotating shell structure 3 of the rotary kiln 2.

The device 1 has a guide pipe 7 configured to receive and hold a thermocouple unit 8. The device 1 has a thermocouple drive 9 configured to move the thermocouple unit 8 with respect to the guide pipe 7 so that at least one temperature sensitive tip 15 of the thermocouple unit 8 protrudes out of the guide pipe 7.

The device 1 has a guide pipe drive 10 configured to move the guide pipe 7 in and out of the rotary kiln interior 4 through an opening 11 in the shell structure of the rotary kiln 2 and/or configured to move the guide pipe 7 with respect to the frame 5.

The device 1 comprises a temperature determining device 12 functionally connectable to the thermocouple unit 8 by a contact means 13 and configured to receive signals from the thermocouple unit 8.

The thermocouple unit 8 comprises a bundle of parallel thermocouples 14 each having a temperature sensitive tip 15.

Each thermocouple 14 in the bundle of parallel thermocouples is selectively functionally connectable to the temperature determining device 12 by the contact means 13. It is possible that the contact means 13 is physically connected to each thermocouple 14 in the bundle of parallel thermocouples so that the contact means allows functional connection between the temperature determining device 12 and any thermocouple 14 in the bundle of parallel thermocouples.

Each thermocouple 14 in the bundle of parallel thermocouples has a longitudinal extension that is different from the longitudinal extension of the other thermocouples 14 in the bundle of parallel thermocouples so that the temperature sensitive tip 15 of each thermocouple 14 in the bundle of parallel thermocouples is in a longitudinal direction A of the bundle of parallel thermocouples located at a different location than the temperature sensitive tip 15 of the other thermocouples 14 in the bundle of parallel thermocouples.

The thermocouple unit 8 is preferably, but not necessarily, releasable received and held in the guide pipe 7 so as to allow replacing of a bundle of parallel thermocouples having all thermocouples 14 worn out with a new thermocouple unit comprising of a bundle of parallel thermocouples.

All thermocouples 14 in the bundle of parallel thermocouples can, as illustrated in figures 8 and 9, have different lengths. In such thermocouple unit 8, each thermocouple 14 in the bundle of parallel thermocouples has a distal end 16 at the temperature sensitive tip 15 and an opposite proximal end 17, and the thermocouples 14 in the bundle of parallel thermocouples are arranged so that the proximal end 17 of each thermocouple 14 in the bundle of parallel thermocouples is in the longitudinal direction A of the bundle of parallel thermocouples located at essentially the same location.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, arranged in a row 21 and in order by length.

The thermocouples 14 in the bundle of parallel thermocouples can alternatively be arranged in a row 21 and in order by length so that the length of each thermocouple 14 in the bundle of parallel thermocouples is defined by the distance C between a midpoint 22 of the bundle of parallel thermocouples and the temperature sensitive tip 15. It is for example possible that all thermocouples 14 in the bundle of parallel thermocouples have the same length and that the thermocouples 14 in the bundle of parallel thermocouples are arranged so that the opposite ends, i.e. the distal ends 16 and the proximal ends 17, of the thermocouples 14 in the bundle of parallel thermocouples are not located at the same location in the longitudinal direction A of the bundle of parallel thermocouples.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, connected together so that the thermocouples 14 are at least partly spaced from one another so that the thermocouples 14 in the bundle of parallel thermocouples does not disturb each other.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, connected together by a connecting part 18 so that the thermocouples 14 are at least partly spaced from one another so that the thermocouples 14 in the bundle of parallel thermocouples does not disturb each other.

In the embodiment of the device illustrated in figures 12 and 13, the rotary kiln 2 has the form of a cylinder and the thermocouples 14 in the bundle of parallel thermocouples are arranged in two rows 21. In the embodiment of the device illustrated in figures 12 and 13, the thermocouples 14 in the bundle of parallel thermocouples are arranged in each row 21 in order of length defined by the length of the longitudinal extension of the thermocouple 14, and the frame 5 is mounted at the outer surface of the shell structure of the rotary kiln 2 so that the rows 21 are parallel with a plane B which is normal to the rotation axis X of the rotary kiln 2, and so that in each row 21 the thermocouple 14 having the longest longitudinal extension is in a direction of rotation Y of the rotary kiln 2 the most upstream thermocouple 14 in the bundle of parallel thermocouples.

In the embodiment of the device illustrated in figures 14 and 15, the rotary kiln 2 has the form of a cylinder and the thermocouples 14 in the bundle of parallel thermocouples are arranged in two rows. In the embodiment of the device illustrated in figures 14 and 15, the thermocouples 14 in the bundle of parallel thermocouples are arranged in each row 21 in order of length defined by the length of the longitudinal extension of the thermocouple 14, and the frame 5 is mounted at the outer surface of the shell structure of the rotary kiln 2 so that each row 21 is parallel with an imaginary plane D which cuts the rotary kiln 2 in two imaginary half-cylinders and so that the thermocouple 14 having the longest longitudinal extension is in a direction of rotation Y of the rotary kiln 2 the most upstream thermocouple 14 in the bundle of parallel thermocouples.

In the embodiments of the device illustrated in figures 12 to 15, the thermocouples 14 in the bundle of parallel thermocouples are arranged in several rows.

The bundle of parallel thermocouples comprise preferably, but not necessarily, at least one guide means 19 configured to guide the bundle of parallel thermocouples in the guide pipe 7.

The guide pipe 7 is preferably, but not necessarily, releasable attached to the frame 5 so as to allow detaching of the guide pipe 7 for example to facilitate inserting of a new bundle of parallel thermocouples into the guide pipe 7.

The guide pipe 7 is preferably, but not necessarily, releasable attached at the guide pipe 7 drive so as to allow detaching of the guide pipe 7 for example to facilitate inserting of a new bundle of parallel thermocouples into the guide pipe 7.

Next the thermocouple unit 8 for use in a device 1 according to any embodiment presented and some embodiments and variants of the thermocouple unit 8 will be described in greater detail.

The thermocouple unit 8 comprises a bundle of parallel thermocouples each thermocouple 14 having a temperature sensitive tip 15.

Each thermocouple 14 in the bundle of parallel thermocouples is selectively functionally connectable to a temperature determining device 12 by a contact means 13. It is possible that the contact means 13 is physically connected to each thermocouple 14 in the bundle of parallel thermocouples so that the contact means allows functional connection with any thermocouple 14 in the bundle of parallel thermocouples.

Each thermocouple 14 in the bundle of parallel thermocouples has a longitudinal extension that is different from the longitudinal extension of the other thermocouples 14 in the bundle of parallel thermocouples so that the temperature sensitive tip 15 of each thermocouple 14 in the bundle of parallel thermocouples is in a longitudinal direction A of the bundle of parallel thermocouples located at a different location than the temperature sensitive tip 15 of the other thermocouples 14 in the bundle of parallel thermocouples.

All thermocouples 14 in the bundle of parallel thermocouples can, as illustrated in figure 8, have different lengths. In such thermocouple unit 8, each thermocouple 14 in the bundle of parallel thermocouples has a distal end 16 at the temperature sensitive tip 15 and an opposite proximal end 17, and the thermocouples 14 in the bundle of parallel thermocouples are arranged so that the proximal end 17 of each thermocouple 14 in the bundle of parallel thermocouples is in the longitudinal direction A of the bundle of parallel thermocouples located at essentially the same location.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, arranged in a row 21 and in order by length.

The thermocouples 14 in the bundle of parallel thermocouples can alternatively be arranged in a row 21 and in order by length so that the length of each thermocouple 14 in the bundle of parallel thermocouples is defined by the distance C between a midpoint 22 of the bundle of parallel thermocouples and the temperature sensitive tip 15. It is for example possible that all thermocouples 14 in the bundle of parallel thermocouples have the same length and that the thermocouples 14 in the bundle of parallel thermocouples are arranged so that the opposite ends, i.e. the distal ends 16 and the proximal ends 17, of the thermocouples 14 in the bundle of parallel thermocouples are not located at the same location in the longitudinal direction A of the bundle of parallel thermocouples.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, connected together so that the thermocouples 14 are at least partly spaced from one another so that the thermocouples 14 in the bundle of parallel thermocouples does not disturb each other.

The thermocouples 14 in the bundle of parallel thermocouples are preferably, but not necessarily, connected together by a connecting part 18 so that the thermocouples 14 are at least partly spaced from one another so that the thermocouples 14 in the bundle of parallel thermocouples does not disturb each other.

The thermocouple unit 8 comprise preferably, but not necessarily, a guide means 19 configured to guide the bundle of parallel thermocouples in a guide pipe 7 configured to releasable and movable receive the thermocouple unit 8.

The bundle of parallel thermocouples is preferably, but not necessarily, releasable and movable arranged in a guide pipe 7 so that the temperature sensitive tip 15 of each thermocouple 14 in the bundle of parallel thermocouples can protrude out of the guide pipe 7, and the thermocouple unit 8 comprise preferably, but not necessarily, a guide means 19 configured to guide the bundle of parallel thermocouples in the guide pipe 7.

The thermocouple unit 8 comprise preferably, but not necessarily, a contact means 13 comprising a plug means 20.

It is apparent to a person skilled in the art that as technology advances, the basic idea of the invention can be implemented in various ways. The invention and its embodiments are therefore not restricted to the above examples, but they may vary within the scope of the claims.