AU729703B2 - Top stuffing box - Google Patents

Description

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT (Original) APPLICATION NO:

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COMPLETE SPECIFICATION LODGED:

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RELATED ART: NAME OF APPLICANT: ACTUAL INVENTOR(S): ADDRESS FOR SERVICE: INVENTION TITLE: SUPERGOLD HOLDINGS PTY LTD DAVID ELWOOK SHERAR, WARREN ROSS STRANGE COLIN ERNEST CROOK.

LORD COMPANY, Patent Trade Mark Attorneys, of 4 Douro Place, West Perth, Western Australia, 6005, AUSTRALIA.

"TOP STUFFING BOX" DETAILS OF ASSOCIATED PROVISIONAL APPLICATION NO'S: P00331 filed on June 10, 1996 The following Statement is a full description of this invention including the best method of performing it known to me/us: 2 The present invention relates to a top stuffing box.

During drilling operations, soil and rock samples are taken as the drill head penetrates downwards into the earth. The samples are taken continuously and are forced to the surface through the centre of the drill shaft by a stream of compressed gas. The sample travels up the drill shaft at a high speed as a combination of solid particles and gas. When the sample stream, consisting of the stream of gas and the particles, exits the drill shaft, it is normally diverted by a top stuffing box to an apparatus for separating the particles from the gas, via the outlet hose. The sample stream is moving at a high speed and is very abrasive. The abrasion caused by the high speed particles impacting the top and side of the top stuffing box which results in rapid wear. The replacement and/or repairing of top stuffing boxes results in a reduction in drilling *:""time and a corresponding loss of productivity.

The present invention seeks to alleviate some if not all of the aforementioned problems.

o. In accordance with one aspect of the present invention there is provided a top stuffing box comprising an outer casing, having an inlet, an outlet and a lining, wherein the cross sectional area of the top stuffing box increases progressively from the inlet to a point intermediate the inlet and the outlet and the lining includes an arcuate roof portion comprising a plurality of replaceable wear tiles, the gas flow being diverted, in use, by the arcuate roof portion from the inlet to the outlet.

The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:- Figure 1 shows a cross sectional side view of the top stuffing box of the present invention; Figure 2 shows an upper perspective view of an insert in accordance with the present invention; Figure 3 shows a top view of the top stuffing box as shown in Figure 1 with a cover plate and an insert removed; and Figure 4 shows a top view of the insert as shown in Figure 2.

Referring to the figures there is shown a top stuffing box 10. The top stuffing box includes an inlet 12, an outlet 14, an outer casing 20, a lining 30, and wear tiles 40. The lining 30 is designed to fit inside the outer casing 20 when in use as seen in Figure 1. The wear tiles 40 are designed to sit on top of the lining 30 as can be seen in Figure 2. The 10 wear tiles 40 and the lining 30 are held in place by a removable cover plate 50 which S•attaches to a flange 22 on the outer casing 20 by a number of bolts 52.

The inlet 12 contains an insert 24. The insert 24 fits into the inlet 12 and is removable to allow for replacement once the insert 24 has worn beyond its serviceable limit.

The lining 30 includes a base 32, and plurality of sides 34, with each side 34 having an arcuate flange 36, as can be seen in Figure 2. Each flange 36 is situated at an edge of the sides 34. The flanges 36 provide a support for the wear tiles 40. The flanges 36 may also act as a wearingsurface.

The wear tiles 40 include straight wear tiles 42 and curved wear tiles 44.

The method of use of the preferred embodiment of the top stuffing box of the present invention will now be described.

In use the top stuffing box 10 may be assembled as follows. The lining 30 is be placed inside the outer casing 20 and the wear tiles 40 may then be placed on top of the lining The cover plate 50 may be attached by the bolts 52 to the flange 22 of the outer casing to hold the lining 30 and wear tiles 40 in place.

4 An inlet pipe (not shown) which may be at the end of a drill shaft, is then connected to the inlet 12. An outlet pipe (not shown) may then be connected to the outlet 14. The sample stream may then travel through the inlet 12 into the interior of the top stuffing box 10 and out the outlet 14. The construction of the lining 30 and wear tiles 40 is such that the high energy sample stream does not contact the outer casing at any point. The sample stream is diverted by the wear blocks through an angle of approximately 90 degrees from the inlet angle of the sample stream to the outlet angle of the sample stream. The wear tiles S. absorb the impact of the high energy particles in the sample stream and thus allow the stream to be diverted without any of the structural components, for example, the outer 10 casing 20, being worn or damaged. The base 32 and sides 34 of the lining 30 protect the parts of the outer casing 20 not covered by the wear tiles 40 from damage or wear caused by the sample stream. The base 32 and the sides 34 do not receive the full impact of the sample stream and therefore do not need to be as wear resistant or as thick as the wear *tiles The shape of the top stuffing box 10 defined by the base 32 and the roof formed by the wear tiles 40 is such that the interior ofthe top stuffing box has a progressively increasing cross sectional area, as seen by the incoming sample stream, up to approximately half way along the top stuffing box 10. The increase in the cross sectional area of the interior of the top stuffing box 10 causes the sample stream to reduce its velocity, and therefore the energy of the particles in the stream is reduced. The reduction of the energy of the particles reduces the wear on the interior wearing surfaces, being wear tiles 40 and lining This increases the working life of the wearing components. To check the serviceability of the wearing components the cover plate 50 may be removed. This allows the condition of the wear tiles 40, the lining 30 and the insert 24 to be observed and components may be replaced as necessary.

The wear tiles 40 may be made from any hard wearing material that is capable of absorbing the impact of the sample particles. The outer casing 20, the inlet 12, outlet 14 may be made of, for example, mild steel.

The lining 30 may be made of, for example, magnesium steel. The insert 24 may be made of, for example, mild steel with a hard internal facing.

It is considered within the scope of this invention, if the liner 30 is made from a number of parts. Further there may be more than one inlet to the top stuffing box 10 and/or more *0 deemed to be within the scope of the present invention.

*.o o 0

Claims (6)

1. A top stuffing box as herein described, comprising an outer casing, having an inlet, an outlet and a lining, wherein the cross sectional area of the top stuffing box increases progressively from the inlet to a point intermediate the inlet and the outlet and the lining includes an arcuate roof portion comprising a plurality of replaceable wear tiles, the gas flow being diverted, in use, by the arcuate roof portion from the inlet to the outlet.

2. A top stuffing box in accordance with claim 1, wherein the gas flow at the outlet is substantially perpendicular to the gas flow at the inlet.

3. A top stuffing box in accordance with claim 1 or 2, wherein the outer casing *includes a removable cover plate which holds in place the replaceable wear tiles.

S4. A top stuffing box in accordance with any one of claims 1 to 3, wherein the lining includes a base and a plurality of sides, the sides each having a flange to support an edge of the wear tiles. 0

5. A top stuffing box in accordance with any one of the preceding claims, wherein the inlet includes a removable insert.

6. A top stuffing box as substantially as hereinbefore described with reference to the accompanying drawings. DATED THIS IST DAY OF DECEMBER 2000 SUPERGOLD HOLDINGS PTY LTD By their Patent Attorneys LORD COMPANY PERTH, WESTERN AUSTRALIA