TWI803674B - Seal assembly and rotating machine - Google Patents

Abstract

A seal assembly for a rotating machine, a rotating machine and method are disclosed. The seal assembly is for a rotating machine comprising shell stators defining at least one pumping chamber and end pieces mountable at either end of the shell stators, the seal assembly comprises: at least one annular seal; and at least one longitudinal seal, the annular seal defining an aperture for receiving the longitudinal seal therewithin, the annular seal being configured to reduce a size of the aperture upon compression of the annular seal. In this way, a multi-component seal assembly is provided which benefits from simplicity of manufacture and ease of assembly, but which also provides for the sealing effectiveness of a one-piece seal due to the improved sealing between the annular seal and the longitudinal seal as the aperture which receives the longitudinal seal reduces in size to improve the effectiveness of the seal when the annular seal is compressed.

Description

Sealing assemblies and rotating machines

The field of the invention is a seal assembly for a rotary machine, a rotary machine and method.

Rotating machines such as compressors or pumps require careful design and manufacture in order for the moving parts to fit each other accurately. Providing an effective seal to seal a machine can be problematic, especially when a pressure differential between the machine and the surrounding environment promotes fluid flow. While existing methods can help, they fall short of the desired results. Accordingly, it would be desirable to provide an improved seal.

According to a first aspect, there is provided a seal assembly for a rotary machine comprising a housing stator defining at least one pumping chamber and ends mountable at either end of the housing stators The seal assembly includes: at least one annular seal; and at least one longitudinal seal defining an aperture for receiving the longitudinal seal therein, the annular seal being structured to One of the holes is reduced in size when the annular seal is compressed. This first aspect recognizes that some rotating machine designs have a stator configuration with a line of axial division along one of the stators, which is usually formed from a pair of housing stators (stator halves), and the housing The stator is then received between a pair of end plates. This structural design provides a rotating machine that is easier to assemble and requires a seal along the axial parting line of the stator of the housing and between the stator and the end plate an annular seal. The interface between the longitudinal seal and the annular seal is sometimes referred to as a T-junction. While a one-piece seal could be used to seal both the case stator to case stator interface and between the stator and end plates, such a seal is complex and difficult to mold.

Accordingly, a seal is provided. The seal can be used in a rotating machine. The rotary machine may include a housing stator defining or providing one or more pumping chambers. The rotating machine may include end pieces mountable at either end of the housing stators. The seal may include one or more annular seals. The seal may include one or more longitudinal seals. The annular seal may define or provide a bore or opening. The bore can receive or retain the longitudinal seal. The annular seal may be structured or configured to reduce or constrict the bore when the annular seal is compressed. In this way, a multi-component seal assembly is provided which benefits from simplicity of manufacture and ease of assembly, but also provides the sealing of a one-piece seal due to the improved sealing between the annular seal and the longitudinal seal Effectiveness, because when the annular seal is compressed, the hole receiving the longitudinal seal decreases to increase the effectiveness of the seal.

In one embodiment, the annular seal is configured to reduce the size of the hole when the annular seal is compressed between the housing stators and the end piece. Accordingly, the size or dimensions of the bore may be reduced in response to compression of the annular seal by the housing stators and the end pieces.

In one embodiment, the annular seal is configured to extend in a radial direction when compressing the annular seal in a longitudinal direction between the housing stators and the end piece to reduce the bore. size. Thus, when the annular seal is compressed in the direction in which the longitudinal seals extend, the annular seal extends or expands in a radial direction substantially transverse to the longitudinal direction to reduce the size of the bore.

In one embodiment, the annular seal is configured to reduce the size of the hole compressing the longitudinal seal. Therefore, the size reduction of the hole compresses or squeezes the longitudinal Seals.

In one embodiment, the annular seal is deformable. Thus, the material from which the annular seal is made can deform or flow from one structural design to another in response to a force.

In one embodiment, the annular seal is an elastomer.

In one embodiment, the hole is shaped to fit the longitudinal seal. Thus, the hole can be sized to match the outer shape of the longitudinal seal.

In one embodiment, the annular seal is shaped to tighten the bore when the annular seal is compressed. Thus, when the annular seal is squeezed, the annular seal can tighten, narrow, constrict or tighten the longitudinal seal in the bore.

In one embodiment, a surface bounding the aperture is shaped to compress the longitudinal seal uniformly. Thus, the bore can be shaped to extend uniformly when squeezing the annular seal to compress to apply a uniform pressure along the length of the longitudinal seal within the bore.

In one embodiment, the surface defining the aperture is recessed or concave.

In one embodiment, each annular seal includes a pair of such holes. Thus, two or more holes may be provided, each of which may receive a respective longitudinal seal.

In one embodiment, the annular seal includes an annular surface shaped to engage the housing stators and the end piece. Thus, the seal can be shaped to fit the housing stators and the end piece to facilitate compression of the annular seal.

In one embodiment, the annular surfaces are flat.

In one embodiment, the annular seal includes opposed planar annular surfaces.

In one embodiment, the annular seal has a generally rectangular cross-section.

In an embodiment, the longitudinal seal is deformable.

In one embodiment, the longitudinal seal comprises an elastic and/or ductile material.

In one embodiment, the longitudinal seal comprises a metal and/or an elastomer.

In one embodiment, the longitudinal seal is configured to form a radial protrusion when compressed. Thus, the longitudinal seal may form or produce a radial or annular protrusion on its outer surface when compressed by the annular seal.

In one embodiment, the longitudinal seal is configured to form at least one radial protrusion within the bore when compressed by the housing stators. Thus, the longitudinal seal may form or produce a radial or annular protrusion on its outer surface when compressed by the housing stators. This provides an enhanced seal between the longitudinal seal and the annular seal.

In one embodiment, the longitudinal seal is configured to form at least one radial protrusion extending within the bore when compressed by the housing stators. Thus, the longitudinal seal can extend to fill the hole during compression of the longitudinal seal. Furthermore, this helps to enhance the seal between the longitudinal seal and the annular seal.

In an embodiment, the longitudinal seal is dimensioned to form the at least one radial protrusion within a void defined by the bore when compressed by the housing stators.

In one embodiment, the longitudinal seal is configured to form at least one radial protrusion against an outer annular surface of the annular seal when compressed by the annular seal. Thus, the longitudinal seal may, when compressed, form or create a radial or annular protrusion against or push against an outer surface of the annular seal. This provides a further seal between the longitudinal seal and the annular seal and also locks the longitudinal seal in place from movement during thermal cycling.

According to a second aspect, there is provided a rotary machine comprising: a housing stator defining at least one pumping chamber; end pieces mountable at either end of the housing stator; and the first aspect The sealing assembly of its embodiment.

In an embodiment, at least one of the housing stators and the end pieces includes a member structurally designed to limit outward radial deformation of the annular seal upon compression of the annular seal. This helps prevent material of the annular seal from flowing at the radially outermost surface and promotes flow of material into the bore to enhance the seal between the longitudinal seal and the annular seal.

According to a third aspect, there is provided a method comprising: providing at least one annular seal; providing at least one longitudinal seal defining a bore for receiving the longitudinal seal therein; and compressing The ring seal is reduced in size to one of the holes.

In one embodiment, the method includes compressing the annular seal between the housing stator and an end piece to reduce the size of the bore.

In one embodiment, the method includes compressing the annular seal between the housing stators and the end piece in a longitudinal direction to extend the annular seal in a radial direction to reduce the size of the bore. size.

In one embodiment, the method includes compressing the longitudinal seal by reducing the size of the hole.

In one embodiment, the annular seal is deformable.

In one embodiment, the annular seal is an elastomer.

In an embodiment, the method includes shaping the hole to fit the longitudinal seal.

In an embodiment, the method includes shaping the annular seal to tighten the bore when compressing the annular seal.

In one embodiment, the method includes shaping a surface bounding the bore to uniformly compress the longitudinal seal when compressing the annular seal.

In one embodiment, the surface defining the aperture is recessed.

In one embodiment, the method includes providing a pair of such holes.

In one embodiment, the method includes shaping an annular surface of the annular seal to engage the housing stators and the end piece.

In one embodiment, the annular surfaces are flat.

In one embodiment, the annular seal includes opposed planar annular surfaces.

In one embodiment, the annular seal has a generally rectangular cross-section.

In an embodiment, the longitudinal seal is deformable.

In one embodiment, the longitudinal seal includes at least one of an elastic material and a ductile material.

In one embodiment, the longitudinal seal includes at least one of a metal and an elastomer.

In an embodiment, the method includes forming radial protrusions on the longitudinal seal upon compression.

In one embodiment, the method includes forming at least one radial protrusion within the bore upon compression by the housing stators.

In one embodiment, the method includes forming at least one longitudinal protrusion extending within the bore when compressed by the housing stators.

In an embodiment, the method includes dimensioning the longitudinal seal to form the at least one longitudinal protrusion within a void defined by the bore when compressed by the housing stators.

In one embodiment, the method includes structurally designing the longitudinal seal to form at least one radial protrusion against an outer annular surface of the annular seal when compressed by the annular seal.

In one embodiment, the method includes restricting the Outward radial deformation of the ring seal.

Further specific and better aspects are described in the accompanying independent and subordinate technical solutions. The features of the dependent technical solution may be properly combined with the features of the independent technical solution and combined with features other than those explicitly stated in the technical solution.

Although an apparatus feature is described as being operable to provide a function, it should be understood that this includes an apparatus feature that provides the function or is adapted or structured to provide the function.

10: shell

12: Housing stator

14: Housing stator

16: End plate

16A: Gap

18: End plate

18A: Gap

20: Seal assembly

22: Longitudinal seal

24: Longitudinal seal

24A: Annular protrusion

24B: radial protrusion

26: Ring seal

26A: main surface

26B: main surface

26C: hole

26D: hole

28: Ring seal

28A: main surface

28B: main surface

28C: hole

28D: hole

Embodiments of the present invention will now be further described with reference to the accompanying drawings, wherein: FIG. 1 schematically illustrates a housing of a rotating machine according to an embodiment; FIG. 2 illustrates a seal for sealing the housing according to an embodiment Assembly; Figures 3A-3C schematically show steps for incorporating a seal assembly into a housing according to one embodiment; and Figure 4 shows a hole profile according to one embodiment.

Before discussing the embodiments in more detail, an overview will first be provided. Embodiments provide a sealing arrangement for a multi-component housing of a rotating machine, such as a pump or a compressor. For ease of assembly, the housing or stator of a rotating machine may be formed from multiple components, casings or end plates that need to be sealed after assembly. In one configuration, the stator is formed by joining together two or more stator housing parts or housings, which are then held between a pair of end plates. Stator housing components typically require one or more longitudinal seals along one or more of their joint surfaces, with each end plate requiring an annular seal between the end plate and the stator housing component. Providing an effective seal between an annular seal and a longitudinal seal is problematic, therefore, embodiments provide rings in which The vertical seals have a configuration that receives an aperture of each longitudinal seal. Compressing the annular seal between the end plate and the stator housing component causes the bore therein that receives the longitudinal seal to contract, which provides an enhanced seal between the longitudinal seal and the annular seal. In particular, when the annular seal is deformable, compression of the annular seal causes it to deform, and the sealing material flows responsively. The flow of sealing material causes the size of the pores to decrease thereby compressing the longitudinal seal to enhance the seal. While the longitudinal seal is also deformable, compression of the longitudinal seal by the stator housing part causes the longitudinal seal material to flow and expand into the bore in the annular seal, which also enhances the seal. Compressing the hole during compression of the annular seal causes further flow of material of the longitudinal seal to form an annular protrusion around an outer surface of the annular seal. This also enhances the seal and helps prevent the seal from moving during thermal cycling.

rotating machine

FIG. 1 schematically illustrates a casing 10 of a rotary machine according to an embodiment. The housing 10 includes a pair of housing stators 12 , 14 and a pair of end plates 16 , 18 . The housing stators 12, 14 define recesses that receive components of the rotating machine. The housing stators 12, 14 are brought together to hold the assembly in the recess. Next, the end plates 16 , 18 are joined to hold the housing stators 12 , 14 . This provides a particularly convenient assembly of rotating machines.

However, as will be explained in more detail below, to adequately seal the housing stators 12, 14 together, a pair of longitudinal seals is required. Furthermore, to ensure an adequate seal between the housing stators 12, 14 and the respective end plates 16, 18, a pair of annular seals are required.

Seal assembly

FIG. 2 illustrates a sealing assembly 20 for sealing the housing 10 according to one embodiment. Seal assembly 20 has a pair of longitudinal seals 22 , 24 and a pair of annular seals 26 , 28 .

In this example, the longitudinal seal is an O-ring cord with a circular cross-section and made of an elastomeric material.

The annular seals 26, 28 are annular in shape. In this example, the ring seals 26, 28 are square rings with rounded corners. Major faces 26A, 26B, 28A, 28B are provided proximate to major faces of the end plates 16, 18 and adjacent faces of the housing stators 12, 14. In this example, the annular seals 26, 28 have flat faces, a constant thickness and are made of an elastomer. The annular seals 26, 28 have bores 26C, 26D, 28C, 28D in which the longitudinal seals 22, 24 are received. In this example, the holes 26C, 26D, 28C, 28D are shaped and sized to fit the outer surfaces of the longitudinal seals 22 , 24 .

Although in this example the longitudinal seals 22, 24 have a constant circular cross-section, it should be appreciated that they may have alternative cross-sections such as square, triangular, oval, etc., and that they may have non-uniform cross-sections. Furthermore, the longitudinal seals 22, 24 need not be made of an elastomer, but only deformable, for example of a metal.

Although in this example the annular seals 26, 28 are made of an elastomer, it should be understood that they may be made of any material that is deformable. Although in this example the major faces 26A, 26B, 28A, 28B are planar, it should be understood that they may be any suitable for engaging the major faces of the end plates 16, 18 and adjacent faces of the housing stators 12, 14. shape.

sealed assembly

3A-3C schematically illustrate steps for incorporating a seal assembly 20 into housing 10 according to one embodiment. A housing stator 14 is provided in which components (not shown) of the rotating machine are assembled. The longitudinal seals 22 , 24 are typically placed in seal grooves (not shown) extending along the interface of the housing stator 14 . The housing stator 12 is brought into intimate contact with the longitudinal seals 22 , 24 . The annular seals 26, 28 are received by the projections of the longitudinal seals 22, 24, and these projections pass through the holes 26C, 26D, 28C, 28D. The end plates 16 , 18 are positioned proximate the annular seals 26 , 28 .

As shown in FIG. 3B , the housing stators 12 , 14 are clamped together to radially compress the longitudinal seals 22 , 24 . Longitudinal seals 22, 24 deform and material flows out of the constricted volume between housing stators 12, 14 and creates annular protrusions 24A within bores 26C, 26D, 28C, 28D which reinforce annular seals 26, 28 to longitudinal seal 22 , 24 between the seal.

As shown in Figure 3C, the end plates 16, 18 are brought together to compress the annular seals 26, 28 in the longitudinal direction. This causes the annular seals 26, 28 to deform and material to flow in a radial direction, which reduces the size of the holes 26C, 26D, 28C, 28D and radially compresses the longitudinal seals 22, 24 to strengthen the annular seals 26, 28 and Sealing between the longitudinal seals 22,24. This compression of the longitudinal seals 22, 24 causes material to flow in the longitudinal direction, which causes radial protrusions 24B to be formed adjacent the major faces 26A, 28A of the annular seals 26, 28 to enhance the seal between the annular seals 26, 28 and the longitudinal seal. Seal between pieces 22,24.

Thus, it can be seen that a tight seal is created between the holes 26C, 26D, 28C, 28D and the longitudinal seals 22, 24 due to the tightening of the holes on the longitudinal seals 22, 24 and the presence of the radial protrusion 24B. This helps prevent leaks.

Although in this example the bores 26C, 26D, 28C, 28D are defined by a flat surface to provide a constant aperture throughout the annular seals 26, 28, it will be appreciated that non-flat surfaces may be provided. In particular, a concave surface (as shown in Figure 4) may be provided to provide more uniform compression of the longitudinal seals 22, 24 within the bore.

Furthermore, although in this example the end plates 16, 18 have voids 16A, 18A into which the longitudinal seals 22, 24 protrude, it will be appreciated that the longitudinal lengths of the longitudinal seals 22, 24 may be shorter such that they only partially extend Through holes 26C, 26D, 28C, 28D, it would eliminate the need for voids 16A, 18A in end plates 16, 18.

Accordingly, embodiments provide an elastomeric washer and O-ring cord combination to provide gold Metallic, plated, or coated T-joint seal configurations for clam pumps. The O-ring cord will be clamped by the gasket to provide the required seal at any contact surface. Clamping within the configuration will not be affected by any fixture surface coefficient of friction.

As mentioned above, a pump with an axial parting line along the stator requires a seal at each end of the parting line, referred to as a "T" joint. While a one-piece seal could be used to seal both the stator-to-stator interface and between the stator and end plates, such a seal is complex and difficult to mold.

Some pump surfaces are plated and have a lower coefficient of friction than existing materials. Existing sealing solutions have temperature and surface coefficient of friction limitations which lead to leakage. As process applications become more challenging, electroplated stators and rotors are required to overcome process condensation and corrosion. EXAMPLE An O-ring cord is clamped within a washer that will be immune to heat and surface friction.

In an embodiment, an O-ring tether interconnects between the two washers. It should be appreciated that the cords and washers may have different shapes or thicknesses to suit the configuration of the housing. The O-ring cord is placed between the clamshells. The clamshells are spaced by a tool. Next, washers are placed on both ends. An end plate is placed at both ends without twisting. The clamshells are twisted in turn so that the clamshells are perfectly aligned and sandwich the O-ring cord to create a seal. Due to the compression, the O-ring cord may fill the gasket hole (interconnection). The end plates are twisted in turn. The interconnecting holes will minimize the size and grip the O-ring cord to thus provide a T-junction seal. The O-ring cord is trapped within the gasket thus preventing T-joint seal failure on low friction surfaces. Embodiments use a 2-part elastomer to create a T-joint seal with a plated or coated surface clamshell that has a lower surface coefficient of friction.

Although the illustrative embodiments of the present invention have been disclosed in detail herein with reference to the accompanying drawings, it should be understood that the present invention is not limited to the precise embodiments and those skilled in the art can make the claims without departing from the scope of the appended claims and their equivalents. Various changes may be made herein without delimiting the scope of the invention and modification.

20: Seal assembly

22: Longitudinal seal

24: Longitudinal seal

26: Ring seal

26A: main surface

26B: main surface

26C: hole

26D: hole

28: Ring seal

28A: main surface

28B: main surface

28C: hole

28D: hole

Claims (15)

A seal assembly for a rotating machine comprising a housing stator defining at least one pumping chamber and end pieces mountable at either end of the housing stators, the seal assembly comprising: at least one annular seal; and at least one longitudinal seal defining a bore for receiving the longitudinal seal therein, the annular seal being structured to reduce when the annular seal is compressed A size of the bore; wherein the longitudinal seal is structured to form at least one radial protrusion extending within the bore when compressed by the housing stators. The seal assembly of claim 1, wherein the annular seal is configured to reduce the size of the bore when compressing the annular seal between the housing stators and the end piece. The seal assembly of claim 1 or 2, wherein the annular seal is configured to extend in a radial direction when the annular seal is compressed in a longitudinal direction between the housing stators and the end piece to reduce the size of the hole. The seal assembly of claim 1 or 2, wherein the annular seal is structurally designed to reduce the size of the hole to compress the longitudinal seal. The sealing assembly according to claim 1 or 2, wherein the annular seal is deformable and/or wherein the ring The shaped seal is an elastic body. The seal assembly of claim 1 or 2, wherein the hole is shaped to fit the longitudinal seal. The seal assembly of claim 1 or 2, wherein a surface defining the bore is shaped to uniformly compress the longitudinal seal, and wherein the surface defining the bore is recessed. The sealing assembly according to claim 1 or 2, which includes a pair of holes. The seal assembly of claim 1 or 2, wherein the annular seal includes an annular surface shaped to engage the housing stators and the end piece, wherein the annular surfaces are flat and wherein the annular seal has A generally rectangular section. The seal assembly of claim 1 or 2, wherein the longitudinal seal is deformable and includes at least one of an elastic material and a ductile material. The seal assembly according to claim 1 or 2, wherein the longitudinal seal comprises at least one of a metal and an elastomer. The seal assembly of claim 1 or 2, wherein the longitudinal seal is structured to form a radial protrusion when compressed. The seal assembly of claim 1 or 2, wherein the longitudinal seal is dimensioned to be The at least one radial protrusion is formed within a void defined by the bore when the housing stator is compressed. The seal assembly of claim 1 or 2, wherein the longitudinal seal is configured to form at least one radial protrusion against an outer annular surface of the annular seal when compressed by the annular seal. A rotary machine comprising: a housing stator defining at least one pumping chamber; end pieces mountable at either end of the housing stator; and the Seal assembly.

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