WO2002037071A1

WO2002037071A1 - Flexible probe assembly

Info

Publication number: WO2002037071A1
Application number: PCT/US2000/041891
Authority: WO
Inventors: Leonard W. Moore; Albert Badgen; Tom Fishwick; Erwin Madden
Original assignee: Moore Industries International, Inc.
Priority date: 2000-11-02
Filing date: 2000-11-02
Publication date: 2002-05-10
Also published as: AU2001236423A1

Abstract

A flexible probe assembly (50) can be easily removed from or inserted into a temperature tramsmitter unit (76) of the type typically used in industrial monitoring of control systems. Typically the probe assembly (50) includes a temperature sensor (52) within a protective shell (54) and a set of lead wires (62) that extend the length of the probe assembly (50). Various flexible probe bodies might be used. The outer portion of the flexible probe body might be a spring (58), with the sensor shell (54) on one end of the spring (58) and the lead wires (62) from the sensor (52) extending axially along the center of the spring (58). The flexible body of the probe assembly (50) is sufficiently large in cross section to be guided by the inner diameter of the well bore and sufficiently rigid lengthwise when inserted within the well bore to place the sensor (52) of the probe reliably adjacent the bottom of the well's central bore.

Description

FLEXIBLE PROBE ASSEMBLY

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention generally relates to industrial control systems and particularly to a probe that might be used in a temperature transmitter assembly as one of a number of distributed sensing components of an industrial monitoring or control system.

2. Discussion of the Related Art

The present invention finds application in the field of industrial control systems and also in the monitoring of fluid transport systems and manufacturing systems. Implementations of the present invention are expected to find application in different aspects of the oil transport and refining businesses, including in refineries, oil drilling and pumping stations, and in pipelines. Other fields of use include the chemical and petrochemical industries and the waste transport and treatment industries.

Industrial controls and industrial monitoring systems use temperature transmitters to locally collect temperature information and transmit that information to central data collection, monitoring or control facilities. Temperature measurements are taken using any number of conventional temperature sensors and the temperature signal is conditioned and in some implementations encoded or processed so that the temperature signal can reliably be transmitted over long distances. The temperature sensor is generally placed within the pipe, conduit or reaction vessel to be monitored. Because the sensor may be in a harsh environment and may need to withstand substantial temperatures, the temperature sensor is typically encased within a protective assembly and connected to the control or monitoring system through a temperature transmitter spaced from the sensor itself.

FIG. 1 shows a temperature transmitter and housing configured generally as the unit 10 might be installed as part of a control or monitoring system. A temperature sensor is provided within a protective housing known in the art as a well. The illustrated well 12 has a tapered cylindrical exterior so that the well can be inserted into a transport pipe or a vessel such as a reaction vessel, as appropriate to the application, and sealed to the pipe or vessel through a conventional pipe thread fitting. The well is made sufficiently long as to place the temperature sensor at an appropriate position within the environment to be monitored and the well has a diameter appropriate to provide the rigidity and durability required for long-term usage and easy installations. The well may be made, for example, of stainless steel or another material having characteristics appropriate to the environment in which the temperature sensor is to be placed. As shown in FIG. 1, the well 12 preferably has a heavy wall 14 to provide rigidity and to protect a temperature sensor to be placed within a central drilled bore 16 within the well. The well 12 is typically provided with pipe threads 18 appropriate to mounting the well 12 through the wall of a vessel or pipe in a manner that is simple, self-sealing and secure. In the illustrated unit, a temperature sensor is normally installed at the bottom of the central bore 16 and connected to a temperature transmitter 20. The illustrated transmitter 20 includes a temperature display to provide a local temperature indication, but the primary function of the temperature transmitter is to process temperature signals so that they can be sent reliably over distance. The temperature transmitter 20 senses temperature through the sensor, whether by detecting a temperature dependent voltage or by sensing a resistance or other characteristic of the temperature sensor. Temperature signals received by the temperature transmitter are processed and provided over connections to the sensing or monitoring system. In some installations, the temperature information provided to the sensing or monitoring system may be encoded or otherwise processed for better transmission.

Because the temperature transmitter includes potentially sensitive electronics such as a microcontroller or microprocessor, it may be desirable to space the transmitter 20 away from the well 12 and hence from the heat of the pipe or vessel in which the well is inserted. To this end, a lag 22 may be provided between the well 12 and the temperature transmitter 20. The illustrated lag 22 may include a pipe length having pipe thread fittings on either end that couple to other fittings to join the pipe length to the well 12 on one end and to the housing 24 that houses the temperature transmitter 20. It should be apparent that different configurations of lag 22 might be used in the illustrated temperature probe 10 to provide the desired thermal isolation between the temperature transmitter 20 and the heat of the sensed pipe or vessel. Lags typically include a central bore or opening corresponding to the bore in the well to receive the temperature sensor. Lags conventionally are made of steel and have a thermal conductivity typical of steel.

FIG. 2 illustrates the temperature probe 28 presently used in temperature transmitter units of the type illustrated in FIG. 1. The FIG. 2 temperature probe 30, shown in a different scale than the transmitter unit illustrated in FIG. 1, includes a temperature sensor 32 within a hard wall tube 34. The temperature sensor 32 may be a resistor, thermocouple or diode or any of the other known types of temperature sensors. The hard wall tube is typically formed of stainless steel, is about one quarter inch in diameter, and has a rounded or squared bottom. The temperature sensor is fixed in place by a thermally conductive compound 36 shown in the partial cutaway of FIG. 2. Leads 38 extend from the temperature sensor 32 along the length of the temperature probe 28 and out the end of the tube. Two leads are shown, but other configurations such as three or four lead configurations might be used. Epoxy or a potting compound may fill the length of the tube 30 to stably hold the wires 38 in place.

The temperature probe 28 of FIG. 2 is generally on the order of twelve to eighteen inches in length and the length of the probe 28 is selected to extend from the bottom of the central bore 16 within the well 12 of FIG. 1 to a point adjacent to the housing 24. The wires 38 extend from the end of the tube 30 so that when the probe is installed within the well and lag, the wires can be connected to terminals on the temperature transmitter 20 within the housing 24. Lags are not always present in temperature transmitters like that illustrated in FIG. 1 and shorter temperature probes are used for such installations. Generally the diameter of the temperature probe shown in FIG. 2 is closely matched to the inner diameter of the central bore 16, shown in FIG. 1.

In most installations, the temperature transmitter unit is installed in a substantially fixed position on a pipe or vessel as part of a large control or monitoring system. A conduit is generally attached to the transmitter housing on the side of the housing 25 opposite to where the lag or well attaches to the housing 24. The conduit, not shown in the illustration of FIG. 1, carries the wires that connect the temperature transmitter 20 to the rest of the control or monitoring system.

It should be noted that the well and transmitter assembly of FIG. 1, whether as a complete unit or as individual components, is available from Moore Industries of Sepulveda, California. The temperature probe of FIG. 2 is similarly commercially available from Moore Industries.

SUMMARY OF THE PREFERRED EMBODIMENTS It can be awkward or even difficult to replace the probe illustrated in FIG. 2 in the transmitter unit of FIG. 1. This is because the probe is rigid and long and the transmitter is in the way of removing and inserting the probe into the well of the transmitter unit. Replacing the probe requires substantial disassembly of the transmitter unit illustrated in FIG. 1. As the transmitter unit may need to be serviced in elevated, inaccessible or inconvenient locations, it is desirable to provide an easier way to replace a probe in a transmitter unit. To this end, aspects of the present invention provide a flexible probe assembly that can be removed from and inserted into a well with less disassembly of the transmitter unit. Preferably the flexible body of the flexible probe has a diameter corresponding to the inner diameter of the well bore. In addition, the flexible body is sufficiently rigid or resilient to place the sensor of the probe reliably adjacent the bottom of the well bore.

One aspect of the present invention provides a temperature probe for use in a temperature transmitter unit of a type having a housing, a temperature transmitter adapted to fit within the housing and at least one face assembly to close the temperature transmitter within the housing. The housing has at least one opening for holding a probe assembly consisting of at least a well having a center bore for receiving the temperature probe. The temperature probe includes a temperature sensor, a casing at least partially encasing the temperature sensor, wiring connected to the temperature sensor and extending from the casing, and a flexible probe body provided around the wiring and forming a continuous protective covering from the casing along a length of the wiring, the wiring extending from the flexible probe body.

Another aspect of the present invention provides a method of mounting a temperature probe in a temperature transmitter assembly. The temperature transmitter assembly is of the type having a housing, a temperature transmitter and at least one face assembly. The housing has at least one opening for holding a probe assembly consisting of at least a well having a center bore for receiving a temperature probe. The method includes removing the face assembly and removing the temperature transmitter. The temperature probe is inserted through the opening of the housing into the center bore of the probe assembly without dismounting the housing from the well by bending the temperature probe and then seating the temperature probe adjacent the bottom of the well. Yet another aspect of the present invention provides a different method of mounting a temperature probe in a temperature transmitter assembly. The temperature transmitter assembly is of the type having a housing, a temperature transmitter and at least one face assembly. The housing has at least one opening for holding a probe assembly consisting of at least a well having a center bore for receiving a temperature probe. The method includes adjusting the length of the temperature probe to correspond to a separation between a bottom of the well and the temperature transmitter. The method continues by inserting the temperature probe through the opening of the housing into the center bore of the probe assembly without dismounting the housing from the well by bending the temperature probe and then placing the temperature probe adjacent the bottom of the well.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a transmitter unit with housing, lag and well for a sensor probe.

FIG. 2 illustrates a conventional hard wall, rigid probe including a sensor that might be used in the transmitter unit of FIG. 1. FIG. 3 illustrates a flexible probe assembly in accordance with aspects of the present invention.

FIG. 4 illustrates another flexible probe assembly in accordance with aspects of the present invention.

FIG. 5 illustrates a portion of a housing and transmitter in cross- section having a flexible probe assembly similar to that of FIG. 3 installed.

FIG. 6 illustrates another transmitter unit with housing, lag and well for a sensor probe.

FIG. 7 illustrates in partial cross section the transmitter unit of FIG. 6 having a flexible probe assembly similar to that of FIG. 3 installed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention provide a flexible probe assembly that can be easily removed from or inserted into a transmitter unit used in a monitoring or control system. Typically the probe assembly includes a sensor and a set of lead wires that extend the length of the probe assembly to connect the probe to a transmitter. If the system monitors temperature, the sensor is one of the well-known types of temperature sensors such as a resistor, thermocouple or diode. As sensors are often delicate, the sensor is often provided in a protective casing. For example, the sensor may be encased within a small hard shell. When a protective casing is provided for the sensor, the flexible body of the probe assembly preferably contacts the sensor's protective casing when the probe assembly is installed within the bore of the well of the transmitter.

Various flexible probe bodies might be used. For example, the outer portion of the flexible probe body might be defined by a spring, with the sensor casing on one end of the spring and the lead wires from the sensor extending axially along the center of the spring. The ends of the lead wires extend beyond the opposite end of the spring body so that the ends can be connected to the transmitter when the probe is installed within the transmitter unit. In another embodiment, the outer portion of the flexible probe body is defined by hollow ceramic pieces, such as ceramic beads, strung along the wire leads to form a protective structure around the wire leads. Preferably the flexible body of the probe assembly is sufficiently large in cross section to be guided by the inner diameter of the well bore. This facilitates feeding the probe assembly into the bore of the well. The probe is preferably sufficiently rigid lengthwise when inserted within the well bore to place the sensor of the probe reliably adjacent the bottom of the well's central bore. In a practical sense, the term flexible refers to the ability of the probe assembly to be fed through the face of the transmitter housing and into the central bore of the well, so that the probe assembly readily reaches the bottom of the bore. In most installations of a temperature transmitter like that shown in FIG. 1, the well is securely mounted to the wall of the vessel or pipe that contains the material whose temperature is being monitored. For example, the well is typically securely screwed into the wall of the vessel or pipe using the pipe threads 18 shown in FIG. 1. Often temperature transmitters like that illustrated in FIG. 1 are mounted in continuous flow systems or systems under pressure. In such systems it may be difficult or impossible to remove the temperature transmitter from its installation. Consequently, in conventional installations of the FIG. 1 temperature transmitter unit, it is typical to replace faulty or unreliable temperature probes in the field. Replacing a temperature probe like that illustrated in FIG. 2 in the FIG. 1 temperature transmitter unit is difficult.

The following illustrates the difficulty in replacing a conventional temperature probe assembly, like that illustrated in FIG. 2, in a temperature transmitter unit like that illustrated in FIG. 1. Removing the FIG. 2 temperature probe begins by removing the faceplate 40 of the transmitter unit shown in FIG. 1. The illustrated faceplate has glass installed. Other faceplates might be provided including one with a solid aluminum face that does not allow viewing of a display on the temperature transmitter 20. Generally the faceplate is threaded onto the transmitter unit and the faceplate is removed by unscrewing the faceplate from the housing 24. Threading for the faceplate is typically provided in a collar extending from the faceplate.

The temperature transmitter 20, colloquially known in the industry at this time as "the hockey puck," is held in place with a spring clip around the periphery of the transmitter 20. The spring clip is compressed to reduce its diameter and removed to free the temperature transmitter. Then the temperature transmitter is lifted out. Once the temperature transmitter 20 is removed from the housing 24, the various wires attached to the temperature transmitter are removed. The wiring conduit (not shown) normally attached to the face 25 of the housing is removed from the housing, typically by unscrewing a threaded fitting. After that, the housing 24 for the transmitter is unscrewed from the lag or well, depending on the particular configuration. Finally, the hard wall temperature probe, as illustrated in FIG. 2, is withdrawn from the bore 16 of the well 12. A replacement probe assembly like that illustrated in FIG. 2 can then be inserted into the central bore 16 of the well 12.

Reassembly proceeds by reversing the numerous steps discussed above. Those of ordinary skill in this art appreciate that this is an inconvenient process that is made more difficult by the fact that the temperature transmitter unit may be installed in an inaccessible location, for example, one hundred or more feet off the ground in an oil refinery. In addition, large facilities may use many different lengths of temperature probes. Thus, a worker may have to carry many different lengths of replacement probes when servicing temperature transmitters. All of these difficulties are further exacerbated by the fact that installation and servicing of temperature transmitter units often requires consideration of the possibilities of explosions. Thus, installation and servicing generally has to be performed by specially trained workers and special precautions are generally taken to limit the possibilities of explosions. These "explosion proof precautions make the many steps involved in removing and replacing the FIG. 2 temperature probe even more difficult.

By contrast, use of a flexible temperature probe greatly simplifies this process. Flexible temperature probes can be removed from a temperature transmitter unit like that illustrated in FIG. 1 by removing the faceplate 40 of the transmitter housing 24, removing the temperature transmitter 20 from the transmitter assembly housing 24, detaching the probe's wire leads and then extracting the flexible probe from the bore of the well. The flexible temperature probe assembly is replaced in the transmitter assembly by feeding the probe into the bore of the well, attaching the probe's wire leads to the transmitter 20, inserting the transmitter back into the housing and reattaching the face plate. FIGS. 3 and 4 illustrate embodiments of flexible temperature probe assemblies according to aspects of the present invention for use in the simplified probe replacement processed described here.

FIG. 3 shows a flexible probe assembly 50 including a sensor 52 provided within a protective casing 54. The sensor 52 is one of the well- known types of temperature sensors such as a resistor, thermocouple or diode. The protective casing 54 may, for example, be a stainless steel hollow shell having a rounded bottom corresponding in shape and size to the shape of the bottom of the central bore of the well. Stainless steel generally has the durability and ruggedness desired to protect the sensor both as installed and during the installation process. The protective casing 54 has an opening at its top of sufficient size to accept the sensor 52. For the illustrated temperature sensor embodiment, the sensor 52 is preferably held in place within the protective casing by thermally conductive potting compound 56. Spring 58 forms the flexible body of the probe in FIG. 3. As shown in FIG. 3, one end of the spring 58 is coupled to the protective casing 54 by catching the end of the spring 58 in a collar 60 of the protective casing.

A set of lead wires 62 extends from the sensor 52 through the center of the spring and beyond the length of the spring 58 to connect the probe to a transmitter. Two leads are shown, but other configurations such as three or four lead configurations might be used. The schematic illustrations of FIGS. 3 and 4 do not clearly show the insulation on the wires. Of course, these wires are insulated in typical implementations of the FIGS. 3 and 4. The wires are further placed within a jacket (not shown) that holds the wires together and provides further protection for the wires.

The spring 58 is typically stainless steel because it is durable and rugged. Other materials might be used. A primary function of the spring 58 is to protect the leads of the probe assembly 50 before and during installation of the probe into a temperature transmitter unit. To this end, stainless steel is a particularly useful spring material because of its durability. Preferably the spring is sufficiently large in cross section to be guided by the inner diameter of the well bore. Typically the spring has a diameter close to that of the bores of the wells with which the probe is to be used, for example about one quarter inch. This facilitates feeding the probe assembly into the bore of the well smoothly.

The spring 58 does not have to have significant resilience but is preferably sufficiently resilient as to securely hold the sensor in place at or adjacent the bottom of the bore of the well. For example, an installed spring might hold the protective casing 54 against the bottom of the well with a few pounds of forces. The length of the spring 58 determines the length of the probe assembly. In a particularly preferred implementation of the flexible probe assembly, replacement probes are packaged in a standard length expected to be longer than most installations. Thus, both the spring and the lead wires are longer than the combined lengths of the well and lag of the temperature transmitter unit into which the probe is to be inserted. After the probe assembly is inserted into the bore of a well, the servicing worker cuts the end 64 of the spring to define the length of the probe assembly in the field. The lead wires 62 are then cut to a corresponding, slightly longer length to facilitate attaching the lead wires to the transmitter 20 before the transmitter is replaced in the housing of the temperature transmitter unit. This strategy allows the probe assembly to be sized according to a particular installation in the field, which would have been very difficult with the conventional probe illustrated in FIG. 2.

Alternately, different standard lengths of sets of springs 58 and lead wires 62 might be provided so that most packaged probe assemblies have a precut length appropriate to the most common desired probe length for a particular use. A worker might then carry a combination of the precut probe assemblies and a lesser number of uncut probe assemblies to handle unusual configurations as they are found.

FIG. 4 shows a different configuration of a flexible probe assembly that might be used instead of the probe assembly of FIG. 3. Like the probe assembly of FIG. 3, the FIG. 4 probe assembly 68 includes a temperature sensor 52 held in place by thermally conductive potting compound 56 within a protective casing 54. Lead wires 62 extend from the sensor 52 and out the other side of the flexible probe body. In the FIG. 4 configuration, the flexible probe body is provided by hollow ceramic pieces 70, such as ceramic beads, strung along the wire leads to form a protective structure around the wire leads. During installation, the set of beads or pieces are flexible because the beads are able to move freely along the lead wires. The beads can be restrained to some extent, for example by a temporary catch, as only a reasonable amount of flexibility is necessary to make the FIG. 4 probe assembly work properly. The outer diameters of the beads are chosen to be sufficiently large in cross section to be guided by the inner diameter of the well bore. Because the individual beads touch each other, the probe assembly illustrated in FIG. 4 is rigid lengthwise when inserted within the well bore so that the sensor can be reliably positioned adjacent the bottom of the well.

In the illustrated implementation of FIG. 4, ceramic beads 70 define the outer portion of the probe body. Ceramic is a useful material because it is durable and capable of withstanding very high temperatures. Other materials might be used in less demanding applications. The length of the probe assembly 68 illustrated in FIG. 4 is adjustable so that the length of the probe assembly 68 can be selected in the field in a manner similar to that discussed above with respect to FIG. 3. A worker selects a desired length for the FIG. 4 probe assembly by removing or adding ceramic beads 70 to the lead wires 62 as needed. The lead wires 62 are similarly cut to provide an appropriate length beyond the ceramic beads for attaching the lead wires to the transmitter 20 when the transmitter 20 is removed from the transmitter housing 24.

FIG. 5 shows in partial cross section a temperature transmitter unit similar to that of FIG. 1 with an installed temperature probe assembly 74 similar to that illustrated in FIG. 3. The temperature transmitter is not shown in this illustration but is instead indicated by phantom lines at 76 and its housing is indicated in FIG. 5 at 78. A conduit (not illustrated) is typically attached at the fitting 80 to carrying wiring away from the temperature transmitter 76. The probe assembly 74 is mounted by sliding the probe assembly through an opening in lag 82 attached to the housing 78 and into the central bore of a well 84. A spacer 83 is slid over the spring and into the opening in the lag 82 to better position the spring at the center of the lag 82. A cap 86 is slid over the wiring 88 onto the end of the spring and then the spring of the probe assembly is latched in place by a clip 90. The clip has a central opening through which the wiring 88 passes. Preferably the clip 90 is installed after the probe 74 has been slid through the lag and into the well and before the transmitter 76 is placed in the housing 78. Most preferably, the length of the spring, whether provided precut or as cut in the field, is sufficiently long to place slight tension on the spring so that the temperature sensor 92, within its protective casing, is seated at the bottom of the well 84.

FIG. 6 shows another configuration of temperature transmitter that is used. Like the other temperature transmitter units discussed here, the FIG. 6 transmitter unit includes a well 94, an optional lag 96, and a housing 98 for housing a temperature transmitter. FIG. 7 shows in partial cross section a portion of the transmitter unit of FIG. 6 including a temperature transmitter 100 within the housing 98. Elements of the FIG. 7 illustration that are similar to those of the FIG. 5 illustration described above are indicated in FIG. 7 with the same reference numerals as in FIG. 5. A fitting 102 is provided to receive a conduit that carries wiring away from the temperature transmitter 100.

Temperature transmitter 100 is shown spaced from the housing 98 in FIG. 7 and the wiring 86 is shown extending through an opening in the center of this temperature transmitter. This configuration facilitates the easy assembly of this temperature transmitter unit. When the temperature transmitter is inserted into the housing 98, the bottom of the temperature transmitter 100 seats against a retaining structure 104 that presses against the cap 86 on the end of the spring to compress the spring, thereby holding the temperature sensor 92 against the bottom of the central bore in the well 84. It should be noted that the temperature transmitter assembly of FIG. 6 and 7 does not present a difficulty for replacing the temperature probe assembly. That is, a hard wall probe like that shown in FIG. 2 can be removed and replaced in this temperature transmitter with the same ease that the flexible temperature probe can be installed. It is nonetheless preferred that the same flexible probe assembly be used in this temperature transmitter to provide uniformity and reduce the amount of inventory that needs to be kept on hand for repairs.

The temperature probe assembly 74 is replaced in the temperature transmitter unit of FIGS. 6 & 7 in a manner similar to that discussed above. The faceplate of the housing 98 is removed and the temperature transmitter 100 is unfastened, removed and then the temperature probe assembly is cut to length, depending on the type of probe assembly (precut or uncut) being installed. The proper length probe assembly is slid into the lag and the well and then the fitting 104 is provided on the bottom of the temperature transmitter 100 to slightly compress the end of the spring. The wires of the probe assembly 74 are then connected to the temperature transmitter 100 and assembly of the unit is completed.

The present invention has been described in terms of certain preferred embodiments. Those of ordinary skill in the art will appreciate that the teachings of the present invention are not limited to these described embodiments. Those of ordinary skill will appreciate that various modifications and extensions of the described embodiments might be made without varying from the basic teachings of the present invention. Consequently, the scope of the present invention is not to be limited to any of the described embodiments thereof but instead is to be determined from the claims, which follow.

Claims

What is claimed is:

1. A temperature probe for use in a temperature transmitter unit of a type having a housing, a temperature transmitter adapted to fit within the housing and at least one face assembly to close the temperature transmitter within the housing, the housing having at least one opening for holding a probe assembly consisting of at least a well having a center bore for receiving the temperature probe, the temperature probe comprising: a temperature sensor; a casing at least partially encasing the temperature sensor; wiring connected to the temperature sensor and extending from the casing; and a flexible probe body provided around the wiring and forming a continuous protective covering from the casing along a length of the wiring, the wiring extending from the flexible probe body.

2. The temperature probe of claim 1, wherein the flexible probe body comprises a plurality of ceramic beads.

3. The temperature probe of claim 1, wherein the flexible probe body is a spring and the wiring extends axially adjacent a center line of the spring.

4. The temperature probe of claim 3, further comprising a retaining structure that fits over an end of the spring and which, when installed within a temperature transmitter, provides compression along the spring to hold the sensor adjacent a bottom of a bore.

5. The temperature probe of claim 1, further comprising retaining means for holding and end of the flexible probe body in place.

6. The temperature probe of claim 1, further comprising encapsulating compounds partially sealing the open end of the casing.

7. In a temperature transmitter assembly of a type having a housing, a temperature transmitter and at least one face assembly, the housing having at least one opening for holding a probe assembly including at least a well having a center bore for receiving a temperature probe, a method of mounting the probe comprising: removing the face assembly; removing the temperature transmitter; and inserting the temperature probe through the opening of the housing into the center bore of the well without dismounting the housing from the well by bending the temperature probe and then positioning the temperature probe adjacent the bottom of the well.

8. The method of claim 7, wherein the temperature probe comprises a spring with wiring extending axially within the spring.

9. In a temperature transmitter assembly of a type having a housing, a temperature transmitter and at least one face assembly, the housing having at least one opening for holding a probe assembly including at least a well having a center bore for receiving a temperature probe, a method of mounting the temperature probe comprising: adjusting the length of the temperature probe to correspond to a separation between a bottom of the well and the temperature transmitter; and inserting the temperature probe through the opening of the housing into the center bore of the probe assembly without dismounting the housing from the well by bending the temperature probe and then placing the temperature probe adjacent the bottom of the well.