AU2017100246A4 - Stiffening of trailer tanks - Google Patents

Abstract

Abstract A method of reinforcing a trailer tank incorporates annular reinforcements formed from flat bar. Fig. 2

Description

2017100246 01 Mar 2017

AUSTRALIA

Patents Act 1990

COMPLETE SPECIFICATION

Invention title: “STIFFENING OF TANK TRAILERS”

Applicant:

GENERAL TRANSPORT EQUIPMENT PTY LTD

Associated provisional applications:

The following statement is a full description of the invention, including the best method of performing it known to me: 2017100246 01 Mar 2017 2 “STIFFENING OF TANK TRAILERS”

Field of the Invention [0001] The present invention relates to mobile tanks (trailers) used for the transport of liquids, particularly viscous liquids.

Background to the Invention [0002] Tanks mounted on trailers have long been used for the transportation of liquids. In most cases, such tanks are generally cylindrical, with an axis extending in a generally horizontal, longitudinal direction along a trailer.

[0003] In such a configuration, a tank is highly prone to buckling. A load within the tank has the effect of acting against one part of the cylindrical tank wall, providing a bending force which significantly reduces the overall strength of the tank. In the absence of a load, the tank is susceptible to the impact of external forces (or, in some instances, the creation of an internal vacuum within the tank) which can lead to crumpling.

[0004] In order to guard against buckling failure, trailer-mounted tanks are generally stiffened by the inclusion of circumferential mounted reinforcing members. These often take the form of internal baffles extending around the internal walls of the tank. In other cases external circumferentially mounted reinforcing bands are used. These bands are generally cylindrical, extending along a portion of the tank in an axial direction. Effectively, they act to increase the thickness of the tank along that axial portion. The length of the bands, their axial spacing, the number of bands and their wall thickness all combine to determine the resulting stiffness of the tank.

[0005] The use of internal baffles is particularly useful in the transport of low-viscosity liquids, as there is a tendency for such liquids to ‘slosh’ and internal baffles assist in reducing this tendency.

[0006] Where the liquids to be transported are high-viscosity, such as Ammonium Nitrate Emulsion, ‘sloshing’ becomes less of a problem. With such 3 2017100246 01 Mar 2017 liquids, internal baffles can become quite problematic for filling and emptying a tank, with a significant quantity of the liquid being ‘trapped’ behind the baffles.

[0007] Such high-viscosity liquids generally require a ‘double cone’ trailer tank, arranged to encourage the liquid to drain to a central discharge point, rather than a cylindrical tank. In order to prevent problems with emptying, it is preferable for such tanks to be strengthened with external bands.

[0008] The correct sizing and attachment of reinforcing bands can be a complex exercise, particularly in relation to conical tank trailers. In such a case the bands must be manufactured to be frusto-conical in shape, with a cone angle identical to that of the tank, and an internal diameter precisely corresponding to the required location. In addition, the band must be welded to the tank with a secure and complete weld, which requires a high degree of skill.

[0009] The present invention seeks to provide a means for reinforcing tanks for trailers which may allow for easier construction.

Summary of the Invention [0010] According to one aspect of the present invention there is provided a method of reinforcing a tank, the method including the steps of: forming at least one annular ring from flat bar steel, the annular ring having an inside circumference and an outside circumference; and fixing the inside circumference of the annular ring to the tank.

[0011] Preferably, the annular ring is fixed such that it extends away from the tank at an angle which is within 30° of being radial.

[0012] The annular ring may be formed in a plurality of sections, such that each section may be separately fixed to the tank.

[0013] The method may include the additional step of providing a cylindrical band about the tank, and fixing the ring to the band. 2017100246 01 Mar 2017 4 [0014] The fixing of the ring to the tank may be by welding of the ring directly to the tank, or by welding a band to the tank and welding the ring to the band.

[0015] The tank may be a conical trailer tank.

[0016] According to a second aspect of the present invention there is provided a conical trailer tank including circumferential ring reinforcements, the ring reinforcements being formed from flat bar steel extending away from the trailer tank at an angle within 30° of a radial direction.

Brief Description of the Drawings [0017] It will be convenient to further describe the invention with reference to preferred embodiments of the present invention. Other embodiments are possible, and consequently the particularity of the following discussion is not to be understood as superseding the generality of the preceding description of the invention. In the drawings: [0018] Figure 1 is a perspective of a tank in accordance with the present invention, shown as mounted to a trailer; [0019] Figure 2 is a perspective of the tank of Figure 1, shown without mountings; [0020] Figure 3 is a schematic view of an end of the tank of Figure 1; [0021] Figure 4 is a general cross section through the tank of Figure 1; [0022] Figures 5a and 5b are examples of two non-radial embodiments of the present invention; and [0023] Figures 6a and 6b are examples of two radial embodiments of the present invention.

Detailed Description of Preferred Embodiments 2017100246 01 Mar 2017 5 [0024] Referring to the Figures, there is shown a tank 10 for location atop a trailer. The tank 10 is generally conical; that is, it extends in a longitudinal direction with circular cross section, and has a decreasing radius away from the centre of the tank 10.

[0025] The tank 10 has a plurality of reinforcing rings 12 located along its length. The rings 12 are circumferential, and are axially spaced along the tank 10. In the embodiment of the drawing the tank 10 has six reinforcing rings 12, however it will be appreciated that more or fewer rings 12 can be used as required.

[0026] Each reinforcing ring 12 consists of a band 14 and an annulus 16.

[0027] The band 14 is generally cylindrical, with an internal radius equal to the radius of the tank 10 at the desired location of the reinforcing ring 12. The arrangement is such that the band 14 can be readily welded to the tank 10 to provide an attachment surface for the annulus 16.

[0028] The annulus 16 is formed from flat metal bar. In the embodiment of the drawings, the annulus 16 is formed from four 90° arcs 18 which have been cut from steel plate. The arcs 18 each have a front face 20 and a rear face 22 which are generally planar, a concave inner edge 24 which has a radius of curvature equal to the outside surface of the band 14, and a convex outer edge 26.

[0029] The annulus 16 is formed about the tank 10 by welding inner edges 24 of the arcs 18 to the band 14, and by welding the arcs to each other in order to form a complete annulus 16.

[0030] The annulus 16 extends away from the tank 10 in a generally radial direction.

[0031] The reinforcing ring 12 acts to assist in strengthening the tank 10, particularly against the possibility of buckling. 2017100246 01 Mar 2017 6 [0032] It will be appreciated that the precise size and orientation of the arcs 18 and thus the annulus 16 can be chosen for particular circumstances. For instance, the annulus 16 may not project away from the tank 10 in a perfectly radial direction, but may be angled relative to the radial direction. It is anticipated that radial angling up to 30° may be appropriate in particular instances. Figures 5a and 5b show reinforcing rings 12 each with an annulus oriented at about 10° to the radial direction, whereas the reinforcing rings of Figures 6a and 6b each have an annulus oriented in the radial direction.

[0033] Similarly, the relative axial length of the band 14 and annular width of the annulus 16 may vary. Figures 5a and 6a show reinforcing rings 12 each having a relatively thin annulus 16, whereas figures 5b and 6b show reinforcing rings 12 each having a relatively wide annulus 16.

[0034] Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Claims (8)

1. Claims

   1. A method of reinforcing a tank, the method including the steps of: forming at least one annular ring from flat bar steel, the annular ring having an inside circumference and an outside circumference; and fixing the inside circumference of the annular ring to the tank.
2. 2. A method of reinforcing a tank as claimed in claim 1, wherein the annular ring is fixed such that it extends away from the tank at an angle which is within 30° of being radial.
3. 3. A method of reinforcing a tank as claimed in claim 1 or claim 2, wherein the annular ring is formed in a plurality of sections, such that each section may be separately fixed to the tank.
4. 4. A method of reinforcing a tank as claimed in any preceding claim, wherein the method includes the additional step of providing a cylindrical band about the tank, and fixing the ring to the band.
5. 5. A method of reinforcing a tank as claimed in any one of claims 1 to 3, wherein the fixing of the ring to the tank is by welding of the ring directly to the tank.
6. 6. A method of reinforcing a tank as claimed in claim 4, wherein the fixing of the ring to the tank is by welding a band to the tank and welding the ring to the band.
7. 7. A method of reinforcing a tank as claimed in any preceding claim wherein the tank is a conical trailer tank.
8. 8. A conical trailer tank including circumferential ring reinforcements, the ring reinforcements being formed from flat bar steel extending away from the trailer tank at an angle within 30° of a radial direction.