AU2019300932A1 - Post - Google Patents

Abstract

An elongate post formed of steel and comprising a plastic coating applied to the post for protection against corrosion is disclosed. In one embodiment, the plastic coating is a thermoplastic coating. In another embodiment, the post comprises a raised region extending around the periphery of the post and located above the ground engaging portion of the post.

Description

POST

PRIORITY DOCUMENTS

[0001] The present application claims priority from Australian Provisional Patent Application No 2018902526 titled“POST” and filed on 12 July 2018, the content of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] The disclosure relates to a post. In a particular form, the present disclosure relates to posts used for fencing arrangements.

BACKGROUND

[0003] Steel posts are used routinely due to their excellent structural properties and cost. One example of a steel post that is commonly used in fencing arrangements is a star picket (or dropper) where a number of these posts are spaced apart and driven into the ground and then horizontal strands of wire are extended between the posts in order to form the fencing boundary. As a steel post is prone to corrosion, they are typically treated in order to reduce degradation of the post.

[0004] In one example, the steel post is coated with a water proofing material such as bitumen where this coating provides a physical barrier between the environment and the underlying steel post. In another example, the steel post may be coated with zinc in a process called galvanising. This process also provides a physical barrier between the environment and the underlying steel and further the zinc acts as a sacrificial anode by corroding before the underlying steel.

[0005] While the above processes are generally adequate it is found in particularly harsh environments, such as those encountered in deserts and coastal lowland areas, that these coatings can be compromised. Soils having high potassium and sodium salt concentrations can react with moisture in the soil to create sulphuric acid which when mixed with oxygen near the soil surface will result in corrosion of the post. Alternatively, soils with high alkalinity and low resistivity can also cause enhanced rates of corrosion. In these environments, the protective coating will often rapidly degrade resulting in the performance of the steel post also being degraded. Especially where these posts are located in remote areas, the process of replacing corroded posts can be both expensive and time consuming. SUMMARY

[0006] In a first aspect, the present disclosure provides an elongate post formed of steel and comprising a plastic coating applied to the post for protection against corrosion.

[0007] In another form, the plastic coating is a polyethylene coating.

[0008] In another form, the plastic coating is a PVC coating.

[0009] In another form, the plastic coating is a polyamide coating.

[0010] In another form, the post includes a ground engaging portion adapted to be driven into the ground and the plastic coating is applied to cover at least the ground engaging portion of the post.

[001 1] In another form, the ground engaging portion of the post is configured as a tapered end of the post.

[0012] In another form, the plastic coating is applied by a dip coating process.

[0013] In another form, the plastic coating is applied by a powdered coating process.

[0014] In another form, the plastic coating is applied by a fluidised bed process.

[0015] In another form, the post comprises a raised region extending around the periphery of the post and located above the ground engaging portion of the post.

[0016] In another form, the raised region is located proximate to the ground engaging portion of the post.

[0017] In another form, the raised region has a height of between 0.8 mm - 1.0 mm with respect to a surface of a post.

[0018] In another form, the raised region has a width of between 4 mm - 6 mm.

[0019] In another form, a surface transition between the post and raised region is smoothly varying.

[0020] In a second aspect, the present disclosure accordingly provides a method for forming a plastic coated steel post, comprising:

pre-treating a steel post to form a pre-treated post; applying a plastic coating material to the pre-treated post to form a processed steel post; and post-processing the processed post to form the plastic coated steel post.

[0021] In another form, pre-treating the steel post includes one or more of the following:

galvanising of the steel post;

chemical cleaning of the steel post;

application of a primer material to the steel post; or

abrasive cleaning of the steel post.

[0022] In another form, applying a plastic coating material to the pre-treated post includes:

immersing and withdrawing the pre-treated post in a container of liquid plastic coating material to coat the pre-treated post to form the processed steel post.

[0023] In another form, the liquid plastic coating material is selected from a polyethylene, PVC or a polyamide plastic material.

[0024] In another form, applying a plastic coating material to the pre-treated post includes:

heating the pre-treated post;

immersing and withdrawing the pre-treated post in fluidised bed containing plastic coating material in powder form to form the processed steel post.

[0025] In another form, the plastic coating material in powder form is selected from a polyethylene, PVC or a polyamide plastic material.

[0026] In another form, applying a plastic coating material to the pre-treated post includes:

earthing the pre-treated post; and

spraying the pre-treated post with plastic coating material in powder form to form the processed steel post.

[0027] In another form, the plastic coating material in powder form is selected from a polyethylene, PVC or a polyamide plastic material.

[0028] In another form, post-processing the processed post includes elevating the processed post to a predetermined temperature for a predetermined time to cure the applied coating to form the plastic coated steel post. [0029] In a third aspect, the present disclosure provides a method for forming an elongate steel post comprising a raised region extending around the periphery of the post and located above the ground engaging portion of the post, comprising:

forming a weld puddle around the periphery of the post corresponding to the raised region; and allowing the weld puddle to solidify.

[0030] In another form, forming a weld puddle around the periphery of the post includes rotating the post about a longitudinal axis before a stationary welding apparatus.

[0031] In a fourth aspect, the present disclosure provides a method for forming an elongate steel post comprising a raised region extending around the periphery of the post and located above the ground engaging portion of the post, comprising:

heating a portion of the elongate steel post corresponding to the raised region;

clamping the post in a clamping arrangement having a moulding region corresponding to the raised region so that the heated portion is located in the moulding region; and

applying a percussive or ramming force to a free end of the elongate steel post to form the raised region.

BRIEF DESCRIPTION OF DRAWINGS

[0032] Embodiments of the present disclosure will be discussed with reference to the accompanying drawings wherein:

[0033] Figure 1 is a perspective view of an elongate post in accordance with an illustrative embodiment;

[0034] Figure 2 is a flowchart of a method of applying a protective coating to an elongate post in accordance with an illustrative embodiment;

[0035] Figure 3 is a perspective view of an elongate post in accordance with another illustrative embodiment;

[0036] Figure 4 is a perspective view of an elongate post including a raised region extending around the periphery of the post in accordance with yet another illustrative embodiment;

[0037] Figure 5 is a detailed sectional view of the raised region of the elongate post illustrated in Figure 4 according to an illustrative embodiment; [0038] Figure 6 is a figurative view of an upset forming arrangement for forming the raised region illustrated in Figure 4;

[0039] Figure 7 is a series of sectional views of different types of posts that may be coated in accordance with an illustrative embodiment; and

[0040] Figures 8a to 8d are a series of views of an impact cap in accordance with an illustrative embodiment.

[0041] In the following description, like reference characters designate like or corresponding parts throughout the figures.

DESCRIPTION OF EMBODIMENTS

[0042] Referring now to Figure 1 , there is shown an elongate post 100 according to an illustrative embodiment. Elongate post 100 in this example comprises a solid steel member 110 having a circular cross-section which at one end includes a ground engaging portion 120 configured as a tapered conical portion 121 which allows post 100 to be driven into the ground with reduced force.

[0043] A plastic coating 130 is applied to post 100 for protection against corrosion. In this illustrative embodiment, plastic coating 110 has been applied to the ground engaging portion 120 of post 100 to assist in protecting the underlying steel member 110 from corrosion and in particular corrosion arising from embedding or driving post 100 into the ground. As would be appreciated, the underlying steel member 110 may have already undergone an initial coating process such as galvanising prior to the application of the plastic coating 130. In this illustrative embodiment, the plastic coating 130 has a thickness between 0.2-1.0 mm. In another example, the entire steel member 1 10 may be coated in a plastic coating.

[0044] Referring now to Figure 2, there is shown a flowchart 200 of the general steps involved in applying a protective plastic coating to a post according to an illustrative embodiment.

[0045] At step 210, the initial steel post is first pre-treated to form a pre-treated post in preparation for the coating process.

[0046] At step 220, a protective plastic coating material is applied to the pre-treated post to form a processed steel post.

[0047] At step 230, the post is then post-processed to form the final plastic coated steel post. [0048] In one example, where the plastic coating is applied by a dip coating process, the step of pre treating the steel post (ie, step 210) involves, in one embodiment, an initial chemical cleaning of the post to remove any contaminants followed by the application of a primer material which in this example is flash dried and baked. The next step of coating the pre-treated post with the protective coating (ie, step 220) in this example includes immersing the primed post in the heated liquid plastic coating material and with the post then withdrawn, causing the post to be coated with a layer of semi-fused plastic coating material applied to the post.

[0049] As would be appreciated, the amount of plastic coating material will broadly depend on the time the post is immersed in the liquid plastic coating material, the temperature of the post prior to immersion in the liquid plastic coating and the type of plastic coating material. As a general rule, a greater initial post temperature combined with longer immersion times will result in a greater film thickness being applied to the post.

[0050] The processed steel post resulting from the dip coating process then goes through the next step of post-processing (ie, step 230). In this example, the post that has been coated with the semi-fused plastic coating material is baked at an elevated temperature between 150°C - 175°C, to complete the fusion process and adhesion of the plastic coating material to the product, and then the coated post is cooled. In one example, the coated post is allowed to air cool. In another example, the coated post may be immersed in a cooling tank having circulating cooling water, with this operation improving the cosmetics of the coated post.

[0051] In one example, the dip coating process is employed to apply a plastic coating material comprising a thermoplastic material in liquid form. In one example, the thermoplastic material is polyvinyl chloride (PVC) in liquid from. In another example, the thermoplastic material comprises polyethylene in liquid form. In yet another example, the thermoplastic material comprises nylon in liquid form. In a further example, the thermoplastic material comprises a plastisol in liquid form. As would be appreciated, any suitable plastic material in liquid form may be adopted depending on requirements.

[0052] In another example, the plastic coating is applied by a fluidised bed process, In this example, the step of pre-treating the steel (ie, step 210) involves, in one embodiment, an initial chemical cleaning of the post to remove any contaminants followed by the application of an abrasive material to physically clean the post in a process such as shot blasting to form the pre-treated post.

[0053] The next step of coating the pre-treated post with the protective coating (ie, step 220) in this example includes initially heating the pre-treated post to a temperature between 250°C - 450°C and then immersing the primed or pre-treated post into a fluidised bed containing the plastic coating material in powder form entrained in air to form a fluid like mixture. This results in the plastic coating material first coating and then melting onto the post to form a smooth continuous plastic coating. The processed steel post with the applied plastic coating material is then post-processed (ie, step 230) by, in one example, cooling the post as described above.

[0054] In one example, the fluidised bed process is employed to apply a thermoplastic coating material in powder form. In one example, the thermoplastic material is polyvinyl chloride (PVC) material in powder form. In a further example, the fluidised bed process is employed to apply a thermoplastic coating material comprising polyethylene in powder form. In yet another example, the applied thermoplastic coating comprises a polyamide or nylon material in powder form. In a further example, the thermoplastic material comprises a plastisol in powder form. As would be appreciated, any suitable plastic material in powder form may be adopted depending on requirements.

[0055] In another example, the plastic coating is applied by a powdered coating process. In this example, the step of pre-treating (ie, step 210) involves in one embodiment an initial chemical cleaning of the post to remove any contaminants followed by the application of an abrasive material to physically clean the post in a process such as shot blasting to form the pre-treated post. The next step of coating the pre-treated post with the protective coating (ie, step 220) in this example includes suspending and earthing the post and then spraying the post with the plastic coating material in powder form that has been fluidised with air, and which further is electrostatically charged, causing it to adhere to the post.

[0056] The resulting processed post is then post-processed (ie, step 230) by, in this example, curing or baking the coated post at an elevated temperature between 150°C - 175°C to complete the fusion process and adhesion of the plastic coating material to the product. The coated post may then be cooled as described above.

[0057] In one example, the powder coating process is employed to apply a thermoplastic coating material in powder form. In one example, the thermoplastic coating material comprises a powder form of polyvinyl chloride (PVC) material. In a further example, the thermoplastic coating material comprises a powder form of polyethylene. In another example, the thermoplastic coating comprises a powder form of polyamide or nylon material. In a further example, the thermoplastic material comprises a plastisol in powder form. As would be appreciated, any suitable plastic material in powder form may be adopted depending on requirements.

[0058] As would be appreciated, the choice as to which coating process to employ will be based on the anticipated environment of the plastic coated steel post. As an example, powder coatings in general are typically thicker than liquid coatings and in particular a fluidised bed coating process may be more advantageously employed for plastic coatings of additional thickness. [0059] In different embodiments, the thickness of the plastic coating is selected from the range of thicknesses including, but not limited to, 0.2 mm - 0.3 mm, 0.3 mm - 0.4 mm, 0.4 mm - 0.5 mm,

0.5 mm - 0.6 mm, 0.6 mm - 0.7 mm, 0.7 mm - 0.8 mm, 0.8 mm - 0.9 mm, 0.9 mm - 1.0 mm, 1.0 mm -

1.1 mm, 1.1 mm - 1.2 mm, 1.2 mm - 1.3 mm, 1.3 mm - 1.4 mm, 1.4 mm - 1.5 mm, 1.5 mm - 1.6 mm,

1.6 mm - 1.7 mm, 1.7 mm - 1.8 mm,l .8 mm - 1.9 mm, 1.9 mm - 2.0 mm, 2.0 mm - 2.1 mm, 2.1 mm -

2.2 mm, 2.2 mm - 2.3 mm, 2.3 mm - 2.4 mm, 2.4 mm - 2.5 mm or greater than 2.5 mm.

[0060] The use of a plastic coating as described above provides the additional benefit that the coating may be coloured and as a result the post may be manufactured having a particular colour for enhanced visibility or colour coding of the post.

[0061] Referring now to Figure 3, there is shown a perspective view of an elongate post 300 according to an illustrative embodiment. Elongate post 300 is in the form of a star picket 310 formed from steel and including three equal spaced flanges 31 1 , 312, 313 having a trigonal planar configuration in cross-section. Star picket 310 further includes a tapered end 321 adapted to be driven into the ground.

[0062] At the opposed end of star picket 310, the right angled edges of the flanges have been chamfered and rounded to remove the sharp corners, in the process reducing the likelihood of the coating delaminating if carelessly hammered into the ground. In one example, a customised driver cap is employed to drive the post into the ground as will be described below. Typically, one of the flanges includes one or more regularly spaced apertures extending down its length (not shown). In this example, the entire star picket 310 has been covered in a plastic coating.

[0063] Referring now to Figure 4, there is shown a detailed perspective view of the end of an elongate post 400 according to an illustrative embodiment prior to coating. Similar to post 300 depicted in Figure 3, post 400 is in the form of a star picket 410 and includes a driveable end 421 which allows star picket 410 to be driven into the ground by applying a driving force to the opposed end of the star picket 410.

[0064] Located proximate to and above the driveable end 421 of star picket 410 there is formed a ridge, raised region or bead 422 raised above the surface 415 of the post 400 and which extends around the periphery or circumference of the post 400 just above the driveable end 421 which in this example is formed as a tapered end.

[0065] Referring now to Figure 5, there is shown a detailed sectional view of the raised region 422 of post 400. In this illustrative embodiment, the raised region 422 has a height H ranging between 0.8 mm to 1.0 mm with respect to the surface of post 400 and a width W ranging between 4 mm - 6 mm. In another example, the raised region 422 has a height H ranging within 0.6 mm to 0.8 mm with respect to the surface of post 400 and a width W ranging between of 4 mm - 8 mm. In yet another example, the raised region 422 has a height H ranging within 0.8 mm to 1.0 mm with respect to the surface of post 400 and a width W ranging between 2 mm - 6 mm. In these examples, directed to a star picket post 410, which is designed to be driven into heavily compacted ground, the transition region 423 between the raised region 422 and the surface 415 of the post 400 varies smoothly. In one example, the transition region 423 is configured to have a minimum equivalent bend radius R of at least 3.0 mm. In another example, the transition region 423 is configured to have a minimum equivalent bend radius R of at least 2.0 mm.

[0066] It has been found unexpectedly that the formation of a raised or bead region 422 proximate to the driveable end of the post prior to coating assists in preventing delamination of the plastic coating particularly when the post is being driven into the ground in heavily compacted soils. In one example, the raised region is located proximate to the driveable end so that in normal use the raised region would be located beneath the ground once the post has been driven into the ground in accordance with standard use.

[0067] The raised or bead region 422 may be formed by any convenient metal forming method. In one example, the raised or bead region 422 is formed by using a welding arrangement to form a weld puddle around the periphery of the post which then solidifies to form the raised or bead region 422. In one example approach, a horizontal rotating platform with a programmable variable speed control is used to mount the post in a horizontal configuration and a robotic MIG welder is employed to form the raised or bead region 422 on the periphery of the post as the post rotates.

[0068] In another example approach, for forming the raised or bead region 422, a heading or upset forming method may be employed to increase the cross section at a location along the post which in this example will be proximate to the driveable end of the post. In one example, a warm heading approach (ie, temperature range of 650°C -l000°C) is employed to heat the steel post below the recrystallization point or transformation temperature but to still allow plastic flow of the steel so that it will adopt a

configuration defined by the die arrangement.

[0069] In this approach, the steel post is heated to the required temperature before it enters the clamping and heading dies. Heating of the steel post may be achieved using any of the following methods including:

• Induction heating where the post is inserted into an alternating current carrying coil so that the region of interest is heated due to eddy currents being formed in the region surrounded by the coil.

• Resistance heating where the region of interest of the post is placed in contact with a low-voltage, high-amperage electrical supply and the region of interest is heated due to the electrical resistance of the metal. • Gas heating where a series of burners, which may be arranged in a ring, are employed to directly heat the region of interest of the post.

[0070] As would be appreciated, warm heading requires less deformation pressure and as a result reduces tooling loads by as much as 50 per cent compared to cold heading where no heating is involved. This also generally prolongs tool life.

[0071] In another example, approach for forming the raised or bead region 422, a hot heading method is employed where the steel post is instead heated to higher temperatures of up to 1 l50°C. This higher temperature results in increased workability of the steel to allow forming of the bead region but the increased temperatures required can involve extra complexity and expense in the process.

[0072] In some applications, however, cold heading may also be used to form the raised or bead region 422 depending on circumstances although, as referred to above, it is appreciated that the clamping and forming pressures that are required are substantially more than those required for warm or hot heading processes.

[0073] Referring now to Figure 6, there is shown an upset forming or heading apparatus 600 for forming a raised region 695 on a post 690 in accordance with an illustrative embodiment. In this example, heading apparatus includes a clamping arrangement 610 comprising a first clamping die 61 1 and a second clamping die 612 arranged to clamp a body portion 691 of post 690 leaving a free end 692 to which a percussive force 640 is applied by ramming die 620. Clamping arrangement 620 includes a moulding region 630 formed around the periphery of the post body 690 sized and shaped in accordance with the raised region or bead 695 that is to be formed on the post.

[0074] The principle function of ramming die 620 is to provide a cycling ramming or percussive force to the free end 692 of the post 690. In this example, ramming die 620 includes a ram or heading tool 625 with a cavity 626 to receive the end of post and an impact region 627 which directly impacts the end of the post. The ram tool 625 may be driven by any convenient means such as a pneumatic or hydraulic system.

[0075] In operation, in order to form the raised region on the post, the location on the post where the raised region is to be formed is first heated as described above and then clamped in the clamping arrangement 610. A percussive force 640 is then applied by ramming die 620 causing the steel to be progressively deformed into moulding region 630 in order to form the raised region 695 on post 690. In this example, the raised region 695 is formed prior to forming a tapered or pointed end of the free end 692 of post 690 to form the driveable end. [0076] In one example, a 20 mm - 30 mm portion of the post that corresponds to the location of the raised region is heated to between 900-1 100°C. Once the correct temperature is attained the post is then transferred into the clamping dies and the heading cycle is initiated. In this example, the clamping arrangement is maintained in position by hydraulic jaws. Once the heading ram has compressed and forced the metal of the post into the moulding regions created between the clamping dies, the post may then be removed and allowed to cool.

[0077] In another example, the post is manufactured in two parts where the first part consists of the body of the post and the second part is the driveable portion which at one end includes a raised region in the form of a flange and at the other end is tapered in order to be driven into the ground. The two parts are then welded together to form the post which will include a raised region located above and near to the tapered end of the post.

[0078] Referring now to Figure 7, there are shown a number of example sectional profiles of different types of posts to which a protective coating and/or a raised region may be applied in accordance with the present disclosure including: square (A), circular (B), planar (C), triangular (D), arcuate (E), rectangular (F) and trigonal planar (G) (ie, a star picket). As would be appreciated, both solid versions of the square (A), circular (B) (eg, see Figure 1), triangular (D) and rectangular (F) posts may also be coated in accordance with the present disclosure. For star picket post G, the angle Q may be varied from the standard 120° depending on requirements by in this example shortening two of trigonal flanges and reducing the included angle down to 90°. This will increase the strength in-line with the longer flange which corresponds to the forward/backward motion of any fence employing these posts which in turn enhances the strength of the fence in this direction.

[0079] Referring now to Figures 8a to 8d there are shown various views of a driving cap 700 for driving a post into the ground according to an illustrative embodiment. In this example, driving cap 700 has a body 710 of a generally cylindrical configuration and including a receiving region 720 sized and shaped to receive the end of a post which is to be driven into the ground. In this illustrative embodiment, the profile 725 of receiving region 720 of driving cap 700 is sized and shaped to conform to that of a star picket post and in particular with the star picket post G depicted in Figure 6 having a reduced angle from the standard 120° between two of the trigonal flanges.

[0080] As would be appreciated, the receiving region may be configured as required depending on the type of post it will be used with. Driving cap 700 is formed as a unitary body of a resilient material such as polyurethane or equally any other suitable resilient material. In this example, driving cap 700 has a height of approximately 40 mm and an outer diameter of approximately 61.5 mm and the depth of receiving region 720 mm is approximately 25 mm to 30 mm [0081] In operation, the end of the post is inserted into the receiving region 720 prior to driving the post into the ground. As would be appreciated, there are various methods for driving a post into the ground including the use of a jackhammer or equivalent, a post driver which consists of a hollow cylindrical metal body having side handles which is fitted over the end of the post and the use of a sledge hammer or other impact tool. Each of these methods may potentially damage the end of the post and the use of driving cap protects the end of the post from the impact force during installation into the ground. In one example, driving cap 700 is fitted over a coated post to minimise damage to the coating during driving the post into the ground.

[0082] Throughout the specification and the claims that follow, unless the context requires otherwise, the words“comprise” and“include” and variations such as“comprising” and“including” will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.

[0083] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge.

[0084] It will be appreciated by those skilled in the art that the invention is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims

Claims (26)

1. An elongate post formed of steel and comprising a plastic coating applied to the post for protection against corrosion.

2. The elongate post of claim 1, wherein the plastic coating is a polyethylene coating.

3. The elongate post of claim 1 , wherein the plastic coating is a PVC coating.

4. The elongate post of claim 1, wherein the plastic coating is a polyamide coating.

5. The elongate post of claim 1 or 2, wherein the post includes a ground engaging portion adapted to be driven into the ground and the plastic coating is applied to cover at least the ground engaging portion of the post.

6. The elongate post of claim 3, wherein the ground engaging portion of the post is configured as a tapered end of the post.

7. The elongate post of any one of the preceding claims, wherein the plastic coating is applied by a dip coating process.

8. The elongate post of any one of claims 1 to 6, wherein the plastic coating is applied by a powdered coating process.

9. The elongate post of any one of claims 1 to 6, wherein the plastic coating is applied by a fluidised bed process.

10. The elongate post of any one of claims 5 to 9, wherein the post comprises a raised region extending around the periphery of the post and located above the ground engaging portion of the post.

11. The elongate post of claim 10, wherein the raised region is located proximate to the ground engaging portion of the post.

12. The elongate post of claim 10 or 1 1, wherein the raised region has a height of between 0.8 mm - 1.0 mm with respect to a surface of a post.

13. The elongate post of any one of claims 10 to 12, wherein the raised region has a width of between 4 mm - 6 mm

14. The elongate post of any one of claims 10 to 13, wherein a surface transition between the post and raised region is smoothly varying.

15. A method for forming a plastic coated steel post, comprising:

pre-treating a steel post to form a pre-treated post;

applying a plastic coating material to the pre-treated post to form a processed steel post; and post-processing the processed post to form the plastic coated steel post.

16. The method of claim 15, wherein pre -treating the steel post includes one or more of the following:

galvanising of the steel post;

chemical cleaning of the steel post;

application of a primer material to the steel post; or

abrasive cleaning of the steel post.

17. The method of claim 15 or 16, wherein applying a plastic coating material to the pre-treated post includes:

immersing and withdrawing the pre-treated post in a container of liquid plastic coating material to coat the pre-treated post to form the processed steel post.

18. The method of claim 17, wherein the liquid plastic coating material is selected from a polyethylene, PVC or a polyamide plastic material.

19. The method of claim 15 or 16, wherein applying a plastic coating material to the pre-treated post includes:

heating the pre-treated post;

immersing and withdrawing the pre-treated post in fluidised bed containing plastic coating material in powder form to form the processed steel post.

20. The method of claim 19, wherein the plastic coating material in powder form is selected from a polyethylene, PVC or a polyamide plastic material.

21. The method of claim 15 or 16, wherein applying a plastic coating material to the pre-treated post includes:

earthing the pre-treated post; and

spraying the pre-treated post with plastic coating material in powder form to form the processed steel post.

22. The method of claim 21, wherein the plastic coating material in powder form is selected from a polyethylene, PVC or a polyamide plastic material.

23. The method of any one of claims 15 to 18, wherein post-processing the processed post includes elevating the processed post to a predetermined temperature for a predetermined time to cure the applied coating to form the plastic coated steel post.

24. A method for forming an elongate steel post comprising a raised region extending around the periphery of the post and located above the ground engaging portion of the post, comprising:

forming a weld puddle around the periphery of the post corresponding to the raised region; and allowing the weld puddle to solidify.

25. The method of claim 24, wherein forming a weld puddle around the periphery of the post includes rotating the post about a longitudinal axis before a stationary welding apparatus.

26. A method for forming an elongate steel post comprising a raised region extending around the periphery of the post and located above the ground engaging portion of the post, comprising:

heating a portion of the elongate steel post corresponding to the raised region;

clamping the post in a clamping arrangement having a moulding region corresponding to the raised region so that that the heated portion is located in the moulding region; and

applying a percussive or ramming force to a free end of the elongate steel post to form the raised region.