Patent Description:
The present disclosure relates to heater assemblies for heating fluid conduits, and more particularly to heater assemblies with improved thermal insulation structures for such heated fluid conduits.

The supply of fluids such as oil, gas, and water, among others, from a supply, e.g., an oil well or a water reservoir, requires transfer of such fluids by conduits or the like. The fluids in the conduits may need to be maintained at or above a certain temperature in order to maintain a free or unrestricted flow of the fluids within the conduits. The fluids may be heated by an electric heater, such as a heat trace type, mounted around the conduits. A thermal insulation jacket is generally mounted around the conduits and the electric heater to reduce heat loss to the surrounding environment.

Generally, fittings are used to join the conduits along their length or to join the conduits to form an angle. When sections of conduits are joined at the fittings, the thermal insulation structure around these fittings are generally custom-designed, resulting in increased manufacturing costs.

The document <CIT> shows a heat trace assembly for heating a conduit that comprises at least one preformed heat trace section defining an elongated body having a channel and a pair of locking edges for securing the heat trace section to the conduit. A connector is secured to the heat trace section for coupling adjacent heat trace sections, and the heat trace section and the connector have mating mechanical features to allow the heat trace sections to be quickly connected to and disconnected from the conduit. In one form, the heat trace section defines a plurality of insulation stand-offs preferably in the form of fins. A connector assembly is also provided with a shell and a fitting heater assembly disposed within the shell, along with heat trace junctions and thermal insulation jackets for the modular heat trace assembly.

In one form of the present disclosure, a modular heater assembly for a fluid conduit system is provided, which includes a plurality of resistive heaters disposed along conduits of the fluid conduit system, a plurality of insulation members disposed around each of the plurality of resistive heaters, and at least one insulation block disposed around a fitting. The fitting is configured to join at least two adjacent sections of the conduits of the fluid conduit system and defines an exterior geometric profile. The insulation block includes a central recess and a peripheral aperture. The central recess defines an internal geometric profile substantially matching the external geometric profile of the fitting. The central recess extends axially in a direction of one of the at least two adjacent sections of conduit. The peripheral aperture defines an internal geometric profile substantially matching an external geometric profile of another of the at least two adjacent sections of the conduits. The peripheral aperture is open to the central recess and extend in a second direction relative to the central recess. The peripheral aperture extends through a sidewall of the insulation block and is axially aligned with the another of the at least two adjacent sections of conduit.

In one variation, the internal geometric profile of the central recess is square or arcuate, such as a cylinder. The central recess may be blind or extend through an entire thickness of the insulation block. The internal geometric profile of the peripheral aperture is arcuate, such as a cylinder.

In other features, the internal geometric profile of the central recess or the peripheral aperture defines opposed, spaced-apart planar surfaces or opposed, spaced-apart arcuate surfaces. The insulation block may include an angled end surface or may include a circular cross-section. In one variation, the insulation block may include a D-shaped cross-section. At least one of the internal geometric profiles of the central recess and the peripheral aperture includes an insulating material. The plurality of resistive heaters are silicone-rubber heaters. Each of the plurality of insulation members include flexible cylindrical foam body. At least one of the flexible cylindrical foam bodies defines a slit along its length.

In another variation, the modular heater assembly further includes at least one heater disposed proximate at least one of the internal geometric profiles of the central recess and the peripheral aperture, and at least one sensor disposed proximate at least one of the internal geometric profiles of the central recess and the peripheral aperture. In one form, the at least one sensor is a temperature sensor.

In still another variation, the central recess and the peripheral aperture define an interior cavity, the interior cavity being open to at least two sides of the insulation block. The interior cavity is open to three sides of the insulation block to define a tee configuration.

Referring to <FIG>, a modular heater assembly <NUM> constructed in accordance with the teachings of the present disclosure is shown. The modular heater assembly <NUM> includes a plurality of electric heaters <NUM> (one is shown in <FIG>) disposed along conduits of the fluid conduit system <NUM> to provide heating to the fluid conduit system <NUM> and a thermal insulation structure (which will be described in more detail below) to provide thermal insulation for the heated fluid conduit system <NUM>. Generally, the fluid conduit system <NUM> carries a variety of fluids, such as processing gases or liquids, that are to be heated by the modular heater assembly <NUM> during operation. In one form, the modular heater assembly <NUM> is a modular silicone rubber gas line heater assembly for heating gas contained in the fluid conduit system <NUM> for a semiconductor processing system (not shown).

Generally, the fluid conduit system <NUM> includes a plurality of conduits <NUM>, <NUM>, <NUM> (shown in <FIG> and only conduit <NUM> being shown in <FIG>) that are joined by a plurality of fittings <NUM> to define a plurality of configurations according to applications/needs.

As clearly shown in <FIG>, the modular heater assembly <NUM> includes a plurality of elongated sections <NUM> (only two are shown in <FIG>) surrounding the conduits <NUM>, <NUM>, <NUM>, and a plurality of insulation blocks <NUM> (only one is shown in <FIG>) disposed around the fittings <NUM>. The insulation blocks <NUM> provide thermal insulation for the fittings <NUM> and may optionally provide heating to the fitting <NUM> if an electric heater is mounted around the fitting <NUM>.

Referring to <FIG>, a portion of one of the elongated sections <NUM> is shown in greater detail. Each of the elongated sections <NUM> includes a thermal insulation member <NUM> having a tubular configuration and an electric heater <NUM> disposed on an inner surface of the thermal insulation member <NUM>. In one form, the electric heater <NUM> is a resistive heater. The thermal insulation member <NUM> may be in the form of a flexible cylindrical foam/sponge body and defines a slit <NUM> extending along its length to allow the thermal insulation member <NUM> to be easily mounted around the conduits <NUM>, <NUM>, <NUM> of the fluid conduit system <NUM> and self-locked around the conduits <NUM>, <NUM>, <NUM> of the fluid conduit system <NUM>. The electric heater <NUM> is attached to an inner surface of the thermal insulation member <NUM> to form an integral unit. The electric heater <NUM> may be any type of heating means, such as a heat trace, a heating foil, a silicone rubber heater, etc., and can be attached to an inner surface of the thermal insulation member <NUM> by any means. In one form, the electric heater <NUM> is a silicone rubber heater, which is thin, lightweight, and flexible and can fit in applications where space is limited. The silicone rubber heater can be easily attached by an adhesive, such as a silicone-based adhesive, to the inner surface of the thermal insulation member <NUM>. The thermal insulation member <NUM> is made of a thermal insulation material and may include a silicone-based material. The thermal insulation structure may further include an insulation jacket <NUM> (shown in <FIG>) wrapped around the thermal insulation member <NUM> and held in place by mechanical means such as snaps or hook and loop (i.e., Velcro®) <NUM>. Similarly, the insulation block <NUM> may also include the insulation jacket <NUM> as shown.

Referring to <FIG>, the conduit system <NUM> includes a first conduit <NUM>, a second conduit <NUM>, and a fitting <NUM> that couples the first conduit <NUM> to the second conduit <NUM> to form a right angle. The fluid conduit system <NUM> may optionally include a third conduit <NUM> (shown in dashed lines) that is coupled to the first conduit <NUM> and the second conduit <NUM> by the fitting <NUM> and that extends along the length direction of the first conduit <NUM>. The third conduit <NUM> may be of the same diameter or different diameter of the first conduit <NUM>. The fluid conduit system <NUM> includes a plurality of fittings <NUM>. One of the fittings <NUM> may be used to joined adjacent two conduits to form a straight line or to define an angle, such as a right angle as shown in <FIG>. Another one of the fittings <NUM> may be used to join adjacent three conduits as shown in <FIG>. In the exemplary example of <FIG>, adjacent three conduits are joined by the fitting <NUM> to define a T-configuration. It should be understood that the teachings of the present disclosure may be applied to any number of conduits and fittings, and connections between conduits and fittings that are at any angle, including a <NUM>° angle (or in other words, a straight section of conduits when transitioning to a smaller or larger diameter, by way of example). Moreover, the fitting <NUM> does not need to have a square block shape as shown in <FIG>. Instead, the fitting <NUM> can be an elbow fitting at <NUM> degrees or at any angle, or a <NUM>-way fitting depending on the number of conduits being connected.

Referring back to <FIG> in conjunction with <FIG>, the elongated sections <NUM> have a tubular configuration and are mounted around the first conduit <NUM>, the second conduit <NUM>, and third conduit <NUM>. In <FIG>, the elongated section <NUM> for the third conduit <NUM> is removed to show the interior cavity of the insulation block <NUM>. The inside diameter of the elongated section <NUM> may be equal to or slightly smaller than the outside diameter of the conduit surrounded by the elongated section <NUM>. In one form, the elongated sections <NUM> may have an inside diameter between about <NUM> inches (<NUM>) and about <NUM> inches (<NUM>). The elongated sections <NUM> may have the same or different lengths and are mounted around the conduits <NUM>, <NUM>. More than one elongated section <NUM> may be mounted around the same conduit depending on the length of the conduit. An insulation block <NUM> is mounted around the fitting <NUM> to provide thermal insulation for the fitting <NUM>. An electric heater <NUM> may or may not be provided inside the insulation block <NUM> depending on applications and needs. Like the thermal insulation member <NUM> of the elongated section <NUM>, the insulation block <NUM> is made of a thermal insulation material and may include a silicone-based material. The insulation block <NUM> has a density between <NUM> to16 pounds per cubic foot (<NUM> to <NUM>/m<NUM>).

Referring to <FIG>, the insulation block <NUM> has a generally puck-like configuration and includes a puck body <NUM> defining a central axis X and a peripheral surface <NUM>. The insulation block <NUM> defines a central recess <NUM> extending along the central axis X, and a peripheral aperture <NUM> extending through a side wall and a peripheral surface <NUM> of the insulation block <NUM>. The peripheral aperture <NUM> is open to the central recess <NUM> and extends from the central recess <NUM> to the outer peripheral surface <NUM> along the Y-axis, which is perpendicular to the central axis X in this form of the present disclosure. The peripheral aperture <NUM> is axially aligned with the conduit extending in the Y direction. Therefore, the central recess <NUM> and the peripheral aperture <NUM> jointly define an interior cavity in a generally tee ("T") configuration to allow tubing to intersect in a tee configuration. In other words, the interior cavity in a generally tee configuration is open at three sides to allow three conduits (e.g., the first, second, and third conduits <NUM>, <NUM>, <NUM>) to be connected.

The central recess <NUM> is configured to accommodate the fitting <NUM> (see <FIG>) therein and thus may define an internal geometric profile substantially matching the external geometric profile of the fitting <NUM>. The central recess <NUM> extends axially in a direction of one of the conduits (i.e., the conduit extending in the X direction as shown in <FIG>). The peripheral aperture <NUM> defines an internal geometric profile substantially matching an external geometric profile of another one of the conduits (i.e., the conduit extending in the Y direction as shown in <FIG>). More specifically, the geometric profile of the central recess <NUM> matches the geometric profile of the fitting <NUM>, which in this exemplary form is square. For example, the central recess <NUM> may have the same dimensions as those of the outer profile of the fitting <NUM> or may be slightly larger than the outer profile of the fitting <NUM> to provide a gap, such as a <NUM>" (<NUM>) gap, to accommodate manufacturing tolerance and for ease of installation when the insulation block <NUM> is mounted around the fitting <NUM>. The peripheral aperture <NUM> is configured to accommodate a conduit connected to the fitting <NUM> and also defines a geometric profile that matches the outer geometric profile of the conduit, which in this form is cylindrical. Similarly, the peripheral aperture <NUM> may have an inside diameter equal to or slightly larger than the outside diameter of the conduit extending therethrough such that a gap of approximately <NUM>" (<NUM>) is present between the insulation block <NUM> and the conduit to accommodate manufacturing tolerance and for ease of installation.

For example, the first conduit <NUM> and the second conduit <NUM> are connected by the fitting <NUM> to form a right angle (or any other angle in other forms of the present disclosure). The first conduit <NUM> extends in a direction parallel to the central axis X of the insulation block <NUM>, and the second conduit <NUM> may be disposed in the peripheral aperture <NUM> and extend along the Y-axis. The third conduit <NUM> is connected to the first conduit <NUM>, is disposed on the other side of the central recess <NUM> and also extends in a direction parallel to the central axis X of the insulation block <NUM>. As such, the fitting <NUM> is thermally insulated by the insulation block <NUM>. And since the fittings <NUM> and the conduits <NUM>, <NUM>, <NUM> are generally of standard sizes, the insulation blocks <NUM> and elongated sections <NUM> can be provided in pre-designed configurations to match the standard sizes of fittings <NUM> and conduits <NUM>/<NUM>/<NUM> to provide a modular and lower cost insulation system.

While the central recess <NUM> is shown to have a square shape, the central recess <NUM> may have any shape and size depending on the shape and size of the fitting <NUM> as long as the fitting <NUM> can be disposed in the central recess <NUM>. The size of the peripheral aperture <NUM> depends on the outside diameter/size of the conduit or the combination of the conduit and the electric heater to be disposed in the peripheral aperture <NUM>.

Referring to <FIG>, a variant of a modular heater assembly <NUM> is shown. The modular heater assembly <NUM> has a structure similar to that of the modular heater assembly <NUM> of <FIG> except that the insulation block <NUM>' is open at only two sides, instead of three sides, to allow only two conduits to be connected. In addition, the modular heater assembly <NUM> includes apertures/openings <NUM> to allow lead wires <NUM> from heater and sensors to pass through.

<FIG> is a perspective view of a variant of the modular heater assembly <NUM>. <FIG> and <FIG> are a perspective view and a front view of portion A of <FIG>, respectively. <FIG> are different cross-sectional views of portion A. <FIG> is a perspective view of portion B (i.e., the insulation block <NUM>') of <FIG>, wherein the insulation block <NUM>' is viewed from a side opposite to the closed end surface <NUM> of the insulation block <NUM>'.

When electric heaters and/or sensors (not shown) are mounted around the conduit system <NUM>, provisions for lead wires <NUM> are needed to connect the heaters/sensors to an external power supply or controller (not shown). The modular heater assembly <NUM> includes a plurality of apertures/openings <NUM> to allow the lead wires <NUM> to pass through. More specifically, the elongated sections <NUM> include the apertures/openings <NUM> as shown, however, the apertures/openings <NUM> may be provided through the insulation block <NUM>' while remaining within the scope of the present disclosure. While <FIG> does not show the apertures/openings <NUM> and the lead wires <NUM>, the apertures/openings <NUM> and the lead wires <NUM> can be provided in the modular heater assembly <NUM> of <FIG> to monitor and control the temperature of the modular heater assembly <NUM> and the conduit system <NUM> being heated.

<FIG> shows the first, second, and third conduits disposed in an X-Y plane and extending in the X direction and the Y direction, whereas <FIG> shows the first and second conduits (without a third conduit) are disposed in an X-Z plane and extend in the X direction and the Z direction. Despite the different orientations and the number of the conduits being connected, the same modular heater assembly including the elongated sections <NUM> and the insulation block(s) <NUM> can be used to provide heating and thermal insulation for the fluid conduit system <NUM> by using an insulation block <NUM>' that is suitable for or that can be easily adapted for this particular fluid conduit system. As clearly shown in <FIG>, the insulation block <NUM>' has a closed end surface <NUM> such that the central recess <NUM> allows only one conduit to be inserted therein (i.e., for an elbow fitting). It is understood that the insulation block <NUM> having a T interior cavity and open at three sides (without the closed end surface <NUM>) for a T fitting can also be used for the fluid conduit system shown in <FIG>. However, the closed end surface <NUM> of the insulation block <NUM>' can reduce heat loss from the fitting to the surrounding environment. It is understood that the modular heater assemblies <NUM>, <NUM> may be used to provide heating and thermal insulation to a fluid conduit system that includes conduits extending in all X, Y, Z directions, among other non-orthogonal directions.

Referring to <FIG>, another variant of the modular heater assembly <NUM> is shown. Similar to the modular heater assemblies <NUM>, <NUM> of <FIG> and <FIG>, the modular heater assembly <NUM> includes a plurality of elongated sections <NUM> and a plurality of insulation blocks <NUM> (only one shown). In this form, the first and second conduits are joined by a fitting (not shown) and are aligned along their lengths. Therefore, the elongated sections <NUM> are aligned along their length and are disposed around the first and second conduits. One insulation block <NUM> is disposed between adjacent two of the elongated sections <NUM> to provide thermal insulation for the fitting. The elongated sections <NUM> may define holes to allow lead wires <NUM> of the heaters or sensors to pass through, as previously described.

Referring to <FIG>, another variant of a modular heater assembly <NUM> constructed in accordance with the teachings of the present disclosure is shown. The modular heater assembly <NUM> includes an elongated section <NUM>, and an insulation block <NUM>. The insulation block <NUM> includes a first mitered section <NUM> attached to an end of the elongated section <NUM>, and a second mitered section <NUM> attached to the first mitered section <NUM>. The elongated section <NUM> has a structure similar to that of the elongated section <NUM> as shown in <FIG> and thus the description thereof is omitted herein for clarity. The first and second mitered sections <NUM> and <NUM> include mitered (angled) end surfaces <NUM>, <NUM> to form a mitered joint. The first mitered section <NUM> and the second mitered section <NUM> are disposed at an end of the elongated section <NUM> and to provide a thermal insulation around a joint where adjacent conduits are connected. The mitered end surfaces <NUM> and <NUM> may be configured to have an angle conforming to an angle defined by adjacent conduits being connected. Additionally and similar to the insulation blocks <NUM>, <NUM>' in <FIG> and <FIG>, the first and second mitered sections <NUM> and <NUM> may define a central recess <NUM> and a peripheral aperture <NUM> (shown in <FIG>) such that a fitting may be disposed inside the first and second mitered sections <NUM>, <NUM>.

It is understood that the first mitered section <NUM> or the second mitered sections <NUM> may be integrally formed with an adjacent elongated section <NUM> to become a one-piece component without departing from the scope of the present disclosure. Alternatively, the first mitered section <NUM> and the second mitered sections <NUM> may be individually used as an insulation block without mating with another mitered section.

Referring to <FIG>, the insulation blocks 16a, 16b, 16d, 16e, 16f may have different interior cavities to accommodate fittings of different geometries. Each of the interior cavities is in a generally tee-configuration and includes a central recess 32a, 32b, 32d, 32e, or 32f, and a peripheral aperture 34a, 34b, 34c, 34d, 34e or 34f of different shapes and/or sizes. In <FIG>, the insulation block 16a has a square/rectangular central recess 32a and a cylindrical peripheral aperture 34a. In <FIG>, the insulation block 16b has a square/rectangular central recess 32b and a peripheral aperture 34b defined by opposing, spaced-apart curved surfaces. In <FIG>, the insulation block 16c has a square/rectangular central recess 32c and a peripheral aperture 34c defined by opposing, spaced-apart flat surfaces. In <FIG>, the insulation block 16d has a cylindrical central recess 32d and a cylindrical peripheral aperture 34d. In <FIG>, the insulation block 16e has a cylindrical central recess 32e and a peripheral aperture 34e defined by opposing, spaced-apart curved surfaces. In <FIG>, the insulation block 16f has a cylindrical central recess 32f and a peripheral aperture 34f defined by opposing, spaced-apart flat surfaces.

While not shown in the drawings, it is understood that the various insulation blocks 16a, 16b, 16c, 16d, 16e, 16f may be modified to provide an interior cavity open at four sides by further forming a second peripheral aperture through the wall of the insulation blocks opposite to the peripheral aperture 34a, 34b, 34c, 34d, 34e, 34f. The various insulation blocks 16a, 16b, 16c, 16d, 16e, 16f may also be modified to provide an interior cavity open at only two sides by forming a closed end surface at an end of the central recess 32a, 32b, 32c, 32d, 32e, 32f.

Referring to <FIG>, a variant of an insulation block <NUM> for mounting around a fitting <NUM> is shown to have a D-shaped outer profile/cross section and an interior cavity <NUM> open at three sides to define a generally tee ("T") interior cavity. More specifically, the insulation block <NUM> includes opposing main surfaces <NUM>, <NUM> (i.e., front and back surfaces) each having a D-shaped peripheral edge, and a peripheral surface <NUM> connecting the D-shaped peripheral edges of the opposing main surfaces <NUM>, <NUM>. The peripheral surface <NUM> includes a flat surface portion 88a and a curved surface portion 88b, which jointly define a D shape. The interior cavity <NUM> includes a central recess <NUM> extending through the opposing main surfaces <NUM>, <NUM>, and a peripheral aperture <NUM> open to the central recess <NUM> and extending through the peripheral surface <NUM>, particularly, the flat surface portion 88a of the insulation block <NUM>. In other words, the central recess <NUM> extends through an entire thickness of the insulation block <NUM>, which is the distance between the opposing main surfaces <NUM>, <NUM>. The insulation block <NUM> defines a slit <NUM>. The slit <NUM> splits the portion of the insulation block <NUM> that defines the peripheral aperture <NUM> into halves such that the insulation block <NUM> can be easily mounted and self-locked around the fitting <NUM> of the fluid conduit system <NUM>.

The central recess <NUM> defines an internal geometric profile substantially matching the external geometric profile of the fitting <NUM>. The peripheral aperture <NUM> defines an internal geometric profile substantially matching an external geometric profile of a conduit inserted into the peripheral aperture <NUM> and connected to the fitting <NUM>. In the exemplary example shown in <FIG>, the internal geometric profile of the central recess <NUM> is square, and the internal geometric profile of the peripheral aperture <NUM> is arcuate, particularly a cylinder. Therefore, the internal geometric profile of the central recess <NUM> defines opposed spaced-apart planar surfaces, and the internal geometric profile of the peripheral aperture <NUM> defines opposed spaced-apart arcuate surfaces (spaced apart by the slit <NUM>). The insulation block <NUM> provides thermal insulation for a fitting <NUM> that can join two or three conduits. The T-shape interior cavity also allows for easy access to the interior of the insulation block <NUM>, for example, for installation of a temperature sensor therein. The temperature sensor may be disposed in the central recess <NUM> or the peripheral aperture <NUM>.

Referring to <FIG>, another variant of an insulation block <NUM>' is structurally similar to the insulation block <NUM> of <FIG> except for the configuration of the interior cavity. Therefore, like reference numbers will be used to designate like components and the detailed description thereof is omitted herein for clarity.

Similarly, the insulation block <NUM>' includes opposing main surfaces <NUM>', <NUM>' and a peripheral surface <NUM>'. The interior cavity <NUM>' is open through only two sides of the insulation block <NUM>' to define a generally "L" interior cavity. The interior cavity <NUM>' includes a central recess <NUM>' and a peripheral aperture <NUM>' open to the central recess <NUM>' and extending through the peripheral surface <NUM>'. Unlike the central recess <NUM>' of <FIG>, the central recess <NUM>' extends through only one (e.g., the front surface) of the main surfaces <NUM>', <NUM>' and the other one (e.g., the back surface) of the main surfaces <NUM>', <NUM>' is closed end surface. Therefore, the central recess <NUM>' is a blind recess. The insulation block <NUM>' defines a slit <NUM>' that splits the portion of the insulation block <NUM>' surrounding the peripheral aperture <NUM>' into halves to allow the insulation block <NUM>' to be easily mounted and self-locked around the fitting <NUM> of the fluid conduit system <NUM>.

Similarly, the central recess <NUM>' defines an internal geometric profile substantially matching the external geometric profile of the fitting <NUM>. The peripheral aperture <NUM>' defines an internal geometric profile substantially matching an external geometric profile of a conduit inserted into the peripheral aperture <NUM>' and connected to the fitting <NUM>. In the exemplary example shown in <FIG>, the internal geometric profile of the central recess <NUM>' is square, and the internal geometric profile of the peripheral aperture <NUM>' is arcuate, particularly a cylinder. The insulation block <NUM>' of <FIG> with a closed end surface provides an improved thermal insulation for a fitting that joins only two conduits.

Referring to <FIG>, the insulation blocks <NUM>, <NUM>' as shown in <FIG> and <FIG> may further include an insulating material <NUM> on an inner surface of the insulation block <NUM>, <NUM>' that defines the interior cavity <NUM>, <NUM>' to provide further thermal insulation. As an example, the insulating material <NUM> may be a coating applied on the internal geometric profiles of the central recess <NUM>, <NUM>' and/or the peripheral aperture <NUM>, <NUM>'. The coating may be an RF coating, a reflective coating, an aerogel coating or any coating known in the art to provide improve thermal insulation. Optionally, one or more electric heaters <NUM>, and/or one or more temperature sensors <NUM> may be provided in the central recess <NUM>, <NUM>' and/or the peripheral aperture <NUM>, <NUM>' of the interior cavity <NUM>, <NUM>' for improved heating control and monitoring. It is understood that while the insulating material <NUM>, the electric heater <NUM> and the temperature sensor <NUM> are described in connection with the insulation blocks <NUM>, <NUM> with a D-shaped outer profile, they can be used in any of the insulation blocks <NUM>, <NUM>', 16a, 16b, 16c, 16d, 16e, 16f, <NUM>, <NUM>, <NUM> previously described in connection with <FIG>.

Referring to <FIG>, a modular heater assembly <NUM> including an insulation block <NUM> having a D-shaped outer profile is shown to be mounted around a fluid conduit system <NUM>. The modular heater assembly <NUM> is structurally similar to the modular heater assembly <NUM> of <FIG> except that an insulation block <NUM> with a D-shaped outer profile as shown in <FIG> is used. It is understood that the insulation block <NUM>' with a closed end surface as shown in <FIG> can also be used in the modular heater assembly <NUM> if the fitting <NUM> is used to join only two conduits at an angle. As shown, the insulation block with a D-shaped outer profile provides improved mating with the portion of the conduit that is inserted into the peripheral aperture (i.e., the portion of the conduit disposed proximate the slit <NUM> of the insulation block <NUM>). The insulation block with a D-shaped outer profile has more materials present above and below the slit <NUM> so that the gap of the slit <NUM> can be more easily reduced after the conduit is inserted into the peripheral aperture <NUM>.

In summary, a modular heater assembly <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> includes a plurality of heating/insulating sections, including elongated sections <NUM>, insulation blocks <NUM>, <NUM>', 16a, 16b, 16c, 16d, 16e, 16f, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>'. These heating/insulating sections may have different lengths and sizes and may be combined in a variety of ways depending on the structure of the conduit system <NUM> and the size of the conduits <NUM>, <NUM>, <NUM>. The insulation blocks <NUM>, <NUM>', 16a, 16b, 16c, 16d, 16e, 16f, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>' may be configured to have different interior cavities that are open at two sides, three sides, or four sides or that have a central recess and a peripheral aperture open to the central recess at different angles to accommodate fittings of different configurations. Therefore, the modular heater assembly according to the teachings of the present disclosure can be easily adapted to a fluid conduit system <NUM> by choosing an insulation block having a conforming interior cavity without any custom-made components and can provide a relatively low cost thermal insulation structure.

Unless otherwise expressly indicated herein, all numerical values indicating mechanical/thermal properties, compositional percentages, dimensions and/or tolerances, or other characteristics are to be understood as modified by the word "about" or "approximately" in describing the scope of the present disclosure. This modification is desired for various reasons including industrial practice, material, manufacturing, and assembly tolerances, and testing capability.

As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A OR B OR C), using a non-exclusive logical OR, and should not be construed to mean "at least one of A, at least one of B, and at least one of C.

In this application, the term "controller" and/or "module" may refer to, be part of, or include: an Application Specific Integrated Circuit (ASIC); a digital, analog, or mixed analog/digital discrete circuit; a digital, analog, or mixed analog/digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor circuit (shared, dedicated, or group) that executes code; a memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components (e.g., op amp circuit integrator as part of the heat flux data module) that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip.

The term memory is a subset of the term computer-readable medium. The term computer-readable medium, as used herein, does not encompass transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium may therefore be considered tangible and non-transitory. Non-limiting examples of a non-transitory, tangible computer-readable medium are nonvolatile memory circuits (such as a flash memory circuit, an erasable programmable read-only memory circuit, or a mask read-only circuit), volatile memory circuits (such as a static random access memory circuit or a dynamic random access memory circuit), magnetic storage media (such as an analog or digital magnetic tape or a hard disk drive), and optical storage media (such as a CD, a DVD, or a Blu-ray Disc).

Claim 1:
A modular heater assembly (<NUM>) for a fluid conduit system (<NUM>), the modular heater assembly comprising a plurality of resistive heaters (<NUM>) disposable along conduits (<NUM>, <NUM>, <NUM>) of the fluid conduit system, and a plurality of insulation members (<NUM>) disposed around each of the plurality of resistive heaters (<NUM>), the modular heater assembly (<NUM>) further comprising at least one insulation block (<NUM>, <NUM>', 16a, 16b, 16c, 16d, 16e, 16d, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>') disposable around a fitting (<NUM>), the fitting (<NUM>) configured to join at least two adjacent sections of the conduits of the fluid conduit system (<NUM>) and defining an exterior geometric profile, the insulation block comprising a central recess (<NUM>, 32a, 32b, 32c, 32d, 32e, 32f, <NUM>, <NUM>') defining an internal geometric profile and extending axially in an axial direction of the one of the at least two adjacent sections of the conduits (<NUM>, <NUM>, <NUM>), and a peripheral aperture (<NUM>, 34a, 34b, 34c, 34d, 34e, 34f, <NUM>, <NUM>') defining an internal geometric profile substantially matching an external geometric profile of another of the at least two adjacent sections of the conduits, being open to the central recess, and extending through a sidewall of the insulation block, characterised in that the internal geometric profile of the central recess (<NUM>, 32a, 32b, 32c, 32d, 32e, 32f, <NUM>, <NUM>') substantially matches the external geometric profile of the fitting, the central recess extending axially in a direction of one of the at least two adjacent sections of conduit and through at least one of opposing main surfaces (<NUM>, <NUM>, <NUM>', <NUM>') of the insulation block (<NUM>, 16a, 16b, 16c, 16d, 16e, 16d) that are perpendicular to the axial direction of the one of the at least two adjacent sections of the conduits, and in that the at least one insulation block (<NUM>, <NUM>', 16a, 16b, 16c, 16d, 16e, 16d, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>') defines a slit (<NUM>) that splits the sidewall of the insulation block surrounding the peripheral aperture (<NUM>, 34a, 34b, 34c, 34d, 34e, 34f) into halves to allow the at least one insulation block (<NUM>, <NUM>', 16a, 16b, 16c, 16d, 16e, 16d, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>') to be mounted and self-locked around the fitting.