Patent Description:
Additive manufacturing processes, in which components may be created by the selective addition of material, in contrast to the traditional formative or subtractive methods, may be desirable for a variety of reasons. However, components formed from additive manufacturing may not be sufficiently hard for some uses or it may desirable for only a part of a component to be formed from a hard material. It has previously been known to form a component using additive manufacturing and then to form one or more hardwearing surfaces on the component. For example, a hardwearing surface may be deposited using a welding process such as a Plasma Transferred Arc (PTA) process. This may be difficult, especially if access to the surface on which the hardwearing surface is to be formed is limited and may require costly bespoke automated processes and equipment.

<CIT> relates to a method for producing a valve arrangement, in particular a hydraulic valve arrangement, which comprises at least one valve housing and at least one electronic component with an electronic component base, the method comprising at least has the following steps: (a) building up the valve housing in layers on a substrate, (b) building up the electronic component base in layers, the electronic component base being connected to the valve housing.

According to a first aspect of the present invention, there is provided a method of manufacturing a valve or an element used to form a valve as claimed in claim <NUM>.

The step of adding the second component to the first part may include placing the first part of the second component in contact with the first part of the first component.

The second component may be secured to the first component by the process of forming the second part of the first component.

The second component may be encapsulated within the first component after formation of the second part of the first component.

The first and second components may be formed from different materials.

The first and second parts of the first component may be formed using the same type of additive manufacturing process.

The first part of the first component may include a recess; and adding the second component to the first part of the first component includes inserting at least a part of the second component into the recess.

The method may further comprise heat treating the valve.

The second component may be harder than the first component.

The first and/or second part of the first component may be formed from at least one of a laser/electron beam melting/sintering process, a powder bed fusion process, a 3D printing process, a selective laser sintering/melting process, a blown powder process, a direct laser deposition process, a freeform manufacturing process, an additive layer manufacturing process, a wire feed process and a direct energy deposition process.

The second component may be formed by at least one of a casting process, a forging process, a rolling process, a drawing process, a machining process, a Hot Isostatically Pressing (HIP) process, and an additive manufacturing process.

The first part of the first component may be formed on a baseplate; and the method further comprises detaching the first part of the first component from the baseplate.

The method may further comprise machining at least one surface of at least one of the first and second components.

A plurality of second components may be added to the first part of the first component.

The method may further comprise: adding a further second component to the second part of the first component; and forming a third part of the first component using additive manufacturing.

The disclosure will now be further described by way of non-limiting examples, with reference to the accompanying figures, in which:.

<FIG> schematically depicts steps taken in the manufacture of a valve, or an element used to form a valve. It will be appreciated that in many cases, the order of the steps may be altered without significantly affecting the process. <FIG> schematically depict a valve, or an element used to form a valve, being formed by an example of such a process at successive stages during the process.

In a first step <NUM>, a first part <NUM> of a first component <NUM> is formed using additive manufacturing, in which the part <NUM> is created by selective addition of material.

Any of a variety of additive manufacturing processes may be used including one or more of a laser/electron beam melting/sintering process, a powder bed fusion process, a 3D printing process, a selective laser sintering/melting process, a blown powder process, a direct laser deposition process, a freeform manufacturing process, an additive layer manufacturing process, a wire feed process and a direct energy deposition process.

The first part <NUM> of the first component <NUM> may comprise any suitable material for a valve, or an element of a valve. For example, the first part <NUM> may comprise a stainless steel (such as <NUM>, <NUM>, 316LN, <NUM>, <NUM>, 304LE, Duplex), a low alloy steel, or a nickel based alloy (such as Monel, Inconel <NUM>, Inconel <NUM>, Inconel <NUM>, Inconel <NUM>, C263).

It will be appreciated that the preceding list is not a list of mutually exclusive processes.

Instead, one or more items within the list may be a subset of another or may overlap with another general process description.

In the example shown in <FIG>, the additive manufacturing process involves providing unfused material <NUM> onto a baseplate <NUM> and selectively fusing the material in layers in order to form a component.

Processes of additive manufacturing may enable formation of complex shapes, including shapes that are not possible or difficult to produce using alternative manufacturing processes, such as casting, forging, rolling or drawing or subtractive methods such as manufacturing methods based on machining surfaces of a section of a material to provide the desired final shape.

As depicted in <FIG>, by selection of the regions in which material is added to the first part <NUM> of the first component <NUM>, a desired shape may be provided. In the example shown in <FIG>, the shape of the first part <NUM> of the first component <NUM> may include a recess <NUM>, from which residual unfused material <NUM> may be removed.

In a step <NUM>, a second component <NUM> is added to the first component <NUM>. For example, a second component <NUM> as illustrated in <FIG> may be added to the first component <NUM>, or a second component <NUM> as illustrated in <FIG> may be added to the first component <NUM>, or a second component <NUM> as illustrated in <FIG> may be added to the first component <NUM>. As shown in <FIG>, in an arrangement, the recess <NUM> formed in the first part <NUM> of the first component <NUM> may be configured such that at least a part of the second component <NUM> can be inserted into the recess <NUM>. The fitting of at least a part of the second component <NUM> into the recess <NUM> within the first part <NUM> of the first component <NUM> may at least temporarily secure the position of the second component <NUM> relative to the first part <NUM> of the first component <NUM> during the manufacturing process.

In an arrangement, the second component <NUM> may include a protrusion having a shape that corresponds to the shape of the recess <NUM> formed in the first part <NUM> and first component <NUM>.

It should be appreciated, however, that the formation of a recess <NUM> in which to receive at least a part of the second component <NUM> is not essential. In an alternative arrangement, the second component <NUM> maybe at least temporarily secured to the first part <NUM> of the first component <NUM> by an adhesive and/or by another bonding process, such as welding. It will also be appreciated that the second component <NUM> may not need to be secured to the first part <NUM> of the second component <NUM> for subsequent processing steps. Accordingly, the second component <NUM> may simply be placed on top of the first part <NUM> of the first component <NUM>.

The second component <NUM> may take any of a variety of forms. It may be formed from the same material as the first component and/or be formed by the same process. Alternatively, it may be formed from a different material from the first component, which may be enabled by forming it by a different process. In particular, the second component <NUM> need not be formed using additive manufacturing but may be formed by an alternative process such as a casting process, a forging process, a rolling process, a drawing process, a machining process and/or a Hot Isostatically Pressing (HIP) process.

The ability to use manufacturing processes other than additive manufacturing in order to form the second component <NUM> may enable the component to have different properties from those which are available from additive manufacturing processes. Alternatively or additionally, the second component <NUM> may be heat treated before it is added to the first part <NUM> of the first component <NUM>, again providing the opportunity to ensure that the second component <NUM> has different properties from the first component <NUM>. In an arrangement, the second component <NUM> may be harder than the first component <NUM>.

The second component <NUM> illustrated in <FIG> comprises a first part <NUM> and a second part <NUM>. The first part <NUM> has a greater hardness than the second part <NUM>. The first part <NUM> comprises a hardfacing alloy, namely Tristelle, Stellite, Talonite, or NOREM. The second part <NUM> may provide a baseplate for the first part <NUM> and may comprise the same material as, or a similar material to, the first part <NUM> of the first component <NUM>. For example, the second part <NUM> may comprise a stainless steel (such as <NUM>, <NUM>, 316LN, <NUM>, <NUM>, 304LE, Duplex), a low alloy steel, or a nickel based alloy (such as Monel, Inconel <NUM>, Inconel <NUM>, Inconel <NUM>, Inconel <NUM>, C263).

The second component <NUM> illustrated in <FIG> comprises a first part <NUM> and a second part <NUM>. Similar to the second component <NUM>, the first part <NUM> has a greater hardness than the second part <NUM>. The first part <NUM> comprises a hardfacing alloy comprising Tristelle, Stellite, Talonite, or NOREM. The second component <NUM> differs from the first component <NUM><NUM> in that the second part <NUM> has a lattice structure or comprises semi-melted material.

The second part <NUM> may comprise the same material as, or a similar material to, the first part <NUM> of the first component <NUM>. For example, the second part <NUM> may comprise a stainless steel (such as <NUM>, <NUM>, 316LN, <NUM>, <NUM>, 304LE, Duplex), a low alloy steel, or a nickel based alloy (such as Monel, Inconel <NUM>, Inconel <NUM>, Inconel <NUM>, Inconel <NUM>, C263).

The second component <NUM><NUM> illustrated in <FIG> and not covered by the present invention comprises only a first part <NUM> that includes a hardfacing alloy such as Tristelle, Stellite, Talonite, or NOREM.

Where the second component <NUM><NUM> or <NUM><NUM> is added to the first component <NUM>, step <NUM> includes placing the first part <NUM> of the second component <NUM><NUM> or <NUM><NUM> in contact with the first part <NUM> of the first component <NUM>. In other words, the second component <NUM><NUM>, <NUM><NUM> is positioned so that the first part <NUM> faces the first part <NUM> of the first component <NUM> (down in <FIG>), and so that the second part <NUM>, <NUM> faces away from the first part <NUM> of the first component <NUM> (up in <FIG>) and towards the energy source of the additive manufacturing device.

It should be appreciated, therefore, that the presently disclosed process for forming an valve or valve element may provide one or more of the benefits of additive manufacturing for the overall form of the valve or valve element but have the benefit of the material properties available for at least one component that are possible when using manufacturing processes other than additive manufacturing.

In a further step <NUM>, as shown in <FIG>, a second part <NUM> of the first component <NUM> is formed using additive manufacturing. The second part <NUM> of the first component <NUM> may be formed by the same additive manufacturing process as the first part <NUM> of the first component <NUM>.

However, this is not essential and an alternative additive manufacturing process may be used for the formation of the second part <NUM>.

The formation of the second part <NUM> of the first component <NUM> may secure the position of the second component <NUM> relative to the first component <NUM>. In an arrangement, this may be effected by the second part <NUM> of the first component <NUM> at least partially surrounding the second component <NUM>. The second part <NUM> of the first component <NUM> may adhere to at least one surface of the second component <NUM>. Alternatively or additionally, the shape of the second part <NUM> of the first component <NUM> formed around the second component <NUM> may physically restrain movement of the second component <NUM> relative to the first component <NUM>.

In an arrangement, as schematically depicted in <FIG>, the second component <NUM> may be encapsulated within the two parts <NUM>, <NUM> of the first component <NUM>.

Where the second component <NUM><NUM> is added to the first part <NUM> of the first component <NUM>, step <NUM> may include providing a third component on top of the second component <NUM><NUM> using (for example) an additive manufacturing process. The third component may comprise the same material as the second part <NUM> of the first component <NUM> and may comprise a lattice structure or may be semi-melted. Consequently, the first part <NUM> of the second component <NUM><NUM> has a greater hardness than the third component.

The use of the second component <NUM><NUM>, <NUM><NUM> may be advantageous in that the second part <NUM>, <NUM> may be positioned between the energy source of the additive manufacturing device and the first part <NUM> of the second component <NUM><NUM>, <NUM><NUM> (as illustrated in <FIG>) during step <NUM> and absorb at least some of the energy emitted by the energy source of the additive manufacturing device. The second part <NUM>, <NUM> may thus reduce the energy received by the first part <NUM> during step <NUM> and may reduce the likelihood of the first part <NUM> cracking/breaking/failing.

Similarly, where the second component <NUM><NUM> is added to the first component <NUM>, the third component formed in step <NUM> above the first part <NUM> of the second component <NUM><NUM> may advantageously reduce the energy received by the first part <NUM> of the second component <NUM><NUM> while the second part <NUM> of the first component <NUM> is being built.

As depicted in <FIG>, after completion of the additive manufacturing process, remaining unfused material <NUM> may be removed. Alternatively or additionally, if the additive manufacturing process involved formation of the first component <NUM> on a baseplate <NUM>, as shown in <FIG>, in a step <NUM>, the baseplate <NUM> may be separated from the valve or valve element, namely detached from the first component <NUM>.

In an arrangement, the method of manufacturing the valve may also include a heat treatment step <NUM>. It should be appreciated that the heat treatment process used will depend upon the materials used to form the valve and the property desired. It should be appreciated that the stage in the process at which the heat treatment step is applied may also vary.

For example, as discussed above, the second component <NUM> may be subjected to a heat treatment before being added to the first component <NUM>. Alternatively or additionally, the first part <NUM> of the first component <NUM> may be heat treated before the addition of the second component <NUM>. Alternatively or additionally, an assembly formed of the first part <NUM> of the first component <NUM> and the second component <NUM> may be heat treated. Alternatively or additionally, the valve or valve element may be heat treated after completion of the formation of the first component <NUM> with the second component <NUM> secured to it.

Where the second component <NUM><NUM> or <NUM><NUM> is added, the method may include a step of hot isostatically pressing the assembly of the first component <NUM> and the second component <NUM><NUM> or <NUM><NUM> to remove any porosity introduced by the lattice structure.

In an arrangement, the method of manufacturing the valve may also include a step <NUM> of machining at least one surface of at least one of the first and second components <NUM>, <NUM>. For example, as shown in <FIG>, such a step may occur after formation of the first component <NUM> including the second component <NUM>. However, it should be appreciated that a machining step may alternatively or additionally be included earlier in the process.

It should be appreciated that, although the above described process only relates to the inclusion of a single second component within a first component <NUM>, by adding the second component <NUM> between the formation of first and second parts <NUM>, <NUM> of the first component <NUM> by additive manufacturing, a valve may be manufactured having a plurality of second components <NUM> incorporated in a similar manner. A plurality of the second components, which may differ from each other, may be added to the part-formed first component <NUM> at the same time. Alternatively or additionally, the formation of the first part <NUM> by additive manufacturing may be paused more than once for the addition of second components <NUM> at different times.

Claim 1:
A method of manufacturing a valve or an element used to form a valve, the method comprising:
forming a first part (<NUM>) of a first component (<NUM>) using additive manufacturing;
the method being characterised by the following:
adding a second component (<NUM><NUM>) to the first part (<NUM>) of the first component (<NUM>), the second component (<NUM><NUM>) comprising a first part (<NUM>) comprising a first material and a second part (<NUM>) comprising a second material, the first material of the first part (<NUM>) having a greater hardness than the second material of the second part (<NUM>), the first part (<NUM>) of the second component (<NUM><NUM>) comprising a hardfacing alloy, namely Tristelle, Stellite, Talonite, or NOREM; and
forming a second part (<NUM>) of the first component (<NUM>) using additive manufacturing.