Handling, storing and treating timber

Abstract

An apparatus 7 to treat a piece of timber is connected to a tank 8 for treating chemicals by a recirculating pump to move chemicals from the tank to the apparatus and back. Conveyors 3 move pieces of

Description

This specification relates to apparatus and method for handling newly cut and dried timber, storing and treating it. The timber is normally in packs and the treatment may be to preserve it for external use. There is a significant trend away from plastics and back to natural materials and this is particularly true of wood and wooden products. The demand for fencing and outdoor pine furniture, etc. is particularly strong and additional handling and treatment installations are required. The trend is to locate these installations near fencing or furniture manufacturers which are normally on Business Parks or Industrial Estates on the edges of cities or conurbations. It is a feature of these handling and treatment installations that they require large storage areas to accommodate the packs of timber, prior to treatment and for an extended period after treatment, so that the excess preservative, or other, chemicals can drain off the treated wood and be fully absorbed into it. Unfortunately, on such Business Parks and Industrial Estates land is expensive. As with all businesses, demand varies over the year and the peak for treated timber is in spring. All businesses have to meet customer demand as and when it arises but to have to buy, or rent, land for only this brief peak demand is a serious financial penalty to a business, particularly if it will under used for the rest of the year. Such costs can make a business financially unviable in this ever-more, cost-conscious and competitive world. There is thus an urgent need to provide additional low cost storage on such timber handling, storage and treatment installations. It is known to store finished articles in multi-storey warehouses. For example, new cars are handled remotely by fork lift means and parked, closely packed, in such warehouses and so are immediately accessible on demand. The same principle is used for other finished, or part finished, items which are often stored on pallets. Pallets are universally used for storage, handling and distribution. If a multi-storey storage and handling system could be provided for timber handling, storage and treatment installations, a given area of land could be used to store several times the number of packs of timber the land would normally hold in just a single storey. This would allow purchases when prices were lower and treatment in advance of the spring peak, thus meeting demand more economically and reliably and also giving staff greater security of employment - considerable ‘positives’ for any business. According to the invention, there is provided a piece of newly cut timber to be treated with a chemical preservative; in combination with an apparatus for the handling, storage and treatment of timber; the apparatus comprising:- i) a reception I dispatch area adapted either receive the piece(s) of timber before treatment or dispatch it I them after treatment, said area having multiple storage layers; ii) a handling means adapted to move the piece of timber on and off the handling means move it vertically on the handling means and move itself and the piece of timber it is carrying between specified locations; iii) a storage area where the piece of timber is storable both before and after treatment, the storage area being provided on a plurality of levels each level being accessible by the handling means iv) apparatus for treating the piece(s) of timber including tankage for storing the chemical and pumping means to pump the chemical from the tankage into the treatment apparatus and return unused chemical back to the tankage after treatment; v) a control means to specify and monitor the location(s) for the piece of timber throughout the process, to control the movement of the handling means between the specified locations, to control the operation of the treatment apparatus and of the chemical pumping means. According to a first variation of the combinations of the invention, the piece of timber is a log. According to a second variation of the combinations of the invention, a plurality of pieces of timber are bundled together to form a pack of timber. According to a third variation of the combinations of the invention, the handling means is provided with sensors to locate it relative to the reception / dispatch area, locations within the storage area and the treatment apparatus. According to a fourth variation of the combinations of the invention, the apparatus for treating the piece / pack of timber is an autoclave provided with means for it to be filled with the chemical and to operate at a predetermined pressure and temperature and for a predetermined time and subsequently for the surplus chemical to be removed. According to a fifth variation of the combinations of the invention, the autoclave is provided with an openable door and a land(s) on which the piece / pack of timber is locatable by the handling means. According to a sixth variation of the combinations of the invention, a tray is provided under the piece I pack of timber when it is moved from the autoclave to the storage area and for the predetermined period of storage after treatment to catch any excess chemical draining off the treated timber. According to a seventh variation of the combinations of the invention, the control means is electronic in nature and provided with sensors, memories and predetermined data to monitor the location(s) of the piece(s) / pack(s) of timber and of the handling apparatus and the parameters of the treatment process. According to the invention, there is provided a method of treating a piece of newly cut timber with a chemical preservative; in combination with an apparatus for the handling, storage and treatment of timber; the method comprising:- i) providing a reception / dispatch area adapted either receive the piece(s) of timber before treatment or dispatch it / them after treatment, said area having multiple storage layers; ii) providing a handling means adapted to move the piece of timber on and off the handling means move it vertically on the handling means and move itself and the piece of timber it is carrying between specified locations; iii) providing a storage area where the piece of timber is storable both before and after treatment, the storage area being provided on a plurality of levels each level being accessible by the handling means iv) providing apparatus for treating the piece(s) of timber including tankage for storing the chemical and pumping means to pump the chemical from the tankage into the treatment apparatus and return unused chemical back to the tankage after treatment; v) providing a control means to specify and monitor the location(s) for the piece of timber throughout the process, to control the movement of the handling means between the specified locations, to control the operation of the treatment apparatus and of the chemical pumping means. According to a first variation of the method of the invention, the piece of timber is bundled with others to form a pack of timber for treatment In a preferred application of the invention, a piece(s) of newly cut, untreated timber, e.g. a log, a pre-cut length or a bundle of logs / pre-cut lengths forming a pack, is / are stored on the site and sequentially each piece / pack is placed in an autoclave and immersed in a preservative chemical for a given time at an elevated temperature and pressure. After treatment, the piece / pack is removed on a drip tray and transferred to a storage location for a period of time to allow any remaining chemical to drip off and be collected and the chemical on the timber to be fully absorbed. After the requisite time in storage, the treated pieces / packs of timber may be dispatched for use. A particular problem with such handling, storage and treatment installations is the large ground area required for storage and the costs of providing this area, e.g. in rent and rates. To mitigate this financial penalty, the invention discloses storage on a plurality of levels. This potentially increases throughput and provides other management economies in running the installation. For a clearer understanding of the invention and to show how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings in which:- Figure 1 is a diagrammatic plan view of one possible installation of the apparatus of the invention. Figure 2 is a perspective view of the front of the installation of the apparatus shown in Figure 1; and Figure 3 is a perspective view of the rear of the installation of the apparatus shown in Figure 1. In the following description, the same reference numeral is used for the same component in different Figures and / or for different components fulfilling identical functions. The following description is written on the basis that a pack of pieces of timber is being treated but the principle applies equally for a single piece of timber, e.g. a log or joist. The term ‘timber1 is intended to cover the wood from newly cut trees requiring preservative treatment. Referring to Fig. 1, a Timber Handling, Storage and Treatment Installation 1 has a reception point, consisting of rack 2 onto which a pack of timber would be placed, e.g. by a lifting device from a lorry (neither shown). Typical timber sections would be 100mm (4ins) square by 4.8m (15ft 9in) long and they would usually be formed into packs, e.g. 12 units wide by 12 units high, i.e. 1.2m high x 1.2m wide x 4.8m Long. Typically, these would be stacked 2 packs high and 3 packs long, making for a total charge size of 2.4m high x 1.2m wide x 14.4m long. These are then secured by circumferential bands (not shown) or held down using clamps (not shown) inside autoclave 7. Ideally, after treatment, the pack 2A would be placed on a tray (not shown) and tray and pack slid 10, as one unit, onto the bed 20 of handler 3. Handler 3 would then move 23 to an appropriate location and slide 11 or 12 tray and pack into a slot in storage area 4 or 5. The tray (not shown) would have lands to engage with the lands on storage structures 22 (Fig. 2). At an appropriate time, the pack would be retrieved 13 or 14 from its location in storage area 4 or 5 by handler 3 and moved 23 along rails 6 into line with autoclave 7 and inserted 15 through open door 7A. The lands on the tray would rest on lands (not shown) inside autoclave 7 so that no wood in the pack would be damaged by the transfer. Door 7A would be closed and autoclave 7 filled with preservative chemical from a tank 8. Four tanks 8A-D are shown as different coloured dyes are added to the preservatives, according to requirements. When full, autoclave 7 is pressurised, e.g. to 12½ bar (188 p.s.i.), and in some cases is heated, depending on the preservative used. Autoclave 7 is then maintained at these conditions for a predetermined time, e.g. 2 hours. After treatment, autoclave 7 is drained and the chemical pumped back to tank 8 and, when sufficiently cooled or vented (if required), door 7A is opened and the pack of treated wood withdrawn 16 on its tray by handler 3 and taken to a special part of the storage, e.g. 5B. The newly treated pack would remain in this special storage 5B for several days while chemical 8 dried - any drips would be caught in the tray for recycling, e.g. to tanks 9. The dwell time also allows the chemical to be fully absorbed into the wood. As before, the lands on the tray would rest on lands (not shown) on the storage structure 22 so that no damage occurred to the wood. When fully dry and when the next order was dispatched, the treated pack would be collected 14, moved 23 by handler 3 and passed 17 to rack 2 for dispatch. Under the Installation’s control system 18, the complete process would be automated including locking and unlocking of door 7A. Control system 18 would be electronic and supported by positioning, and other, sensors (not shown) so that the location and stage of treatment of every pack of timber 2A throughout the process was continuously known and monitored. As shown in Figs. 2 and 3, the storage areas 4, 4A and 5, 5A are two packs high. This is an important use of the ground area of the site 1 and saves the cost while giving greater management flexibility in the operation of the Installation, e.g. timber can be bought at off-peak prices and the Installation 1 can be run at normal capacity throughout the year so that treated stock can be built up for peak demands without requiring expensive overtime. This is also good for staff, who might otherwise be laid off during downturns. Handler 3 has a strongback 24 and a superstructure 21, consisting of four verticals 27, top members 25 and diagonal bracing 26. Hydraulic pistons (not shown) at the comers lift / lower strongback 24, bed 20 and any packs of timber 2A thereon between the upper 4A, 5A and lower 4, 5 storage levels, as required by controller 18. Other means (not shown) engage with the trays to move both trays (not shown) and the packs 2A thereon laterally on and off the handler bed 20 i.e. to or from reception / dispatch, in or out of storage and in or out of the autoclave. Superstructure 21 provides extra stability to the handler when lifting or lowering packs and especially if, after several days drying in storage area 5B, there is stickiness between the lands on the tray and support structure 22 so that movement out of storage may commence jerkily. An inventive aspect of the disclosure is the use of multi-storey storage levels. Though only two storeys 4,4A and 5, 5A are shown, this will have considerable financial and production benefits and further levels can be added, as and when required. Also, additional storage areas, above tanks 8 and 9 and autoclave 7, are possible. Though Installation 1 is a neat and functional design, other arrangements are equally possible, all falling within the scope of the disclosure.

Claims

1. A piece of newly cut timber to be treated with a chemical preservative; incombination with an apparatus for the handling, storage and treatment of timber; the apparatus comprising:-i) a reception I dispatch area adapted either receive the piece(s) of timber before treatment or dispatch it / them after treatment, said area having multiple storage layers;ii) a handling means adapted to move the piece of timber on and off the handling means move it vertically on the handling means and move itself and the piece of timber it is carrying between specified locations;iii) a storage area where the piece of timber is storable both before and after treatment, the storage area being provided on a plurality of levels each level being accessible by the handling meansiv) apparatus for treating the piece(s) of timber including tankage for storing the chemical and pumping means to pump the chemical from the tankage into the treatment apparatus and return unused chemical back to the tankage after treatment;vi) a control means to specify and monitor the location(s) for the piece of timber throughout the process, to control the movement of the handling means between the specified locations, to control the operation of the treatment apparatus and of the chemical pumping means.

2. The combination for treating a piece of newly cut timber, as claimed in claim 1, wherein the piece of timber is a log.

3. The combination for treating a piece of timber, as claimed in claim 2, wherein a plurality of pieces of timber are bundled together to form a pack of timber.

4. The combination for treating a piece of timber, as claimed in claim 3, wherein the handling means is provided with sensors to locate it relative to the reception / dispatch area, locations within the storage area and the treatment apparatus.

5. The combination for treating a piece of timber, as claimed in any preceding claim, wherein the apparatus for treating the piece I pack of timber is an autoclave provided with means for it to be filled with the chemical and to operate at a predetermined pressure and temperature and for a predetermined time and subsequently for the surplus chemical to be removed.

6. The combination for treating a piece of timber, as claimed in claim 5, wherein the autoclave is provided with an openable door and a land(s) on which the piece / pack of timber is locatable by the handling means.

7. The combination for treating a piece of timber, as claimed in any preceding claim, wherein a tray is provided under the piece / pack of timber when it is moved from the autoclave to the storage area and for the predetermined period of storage after treatment to catch any excess chemical draining off the treated timber.

8. The combination for treating a piece of timber, as claimed in any preceding claim, wherein the control means is electronic in nature and provided with sensors, memories and predetermined data to monitor the location(s) of the piece(s) / pack(s) of timber and of the handling apparatus and the parameters of the treatment process.

9. A method of treating a piece of newly cut timber with a chemical preservative; in combination with an apparatus for the handling, storage and treatment of timber; the method comprising:-i) providing a reception / dispatch area adapted either receive the piece(s) of timber before treatment or dispatch it / them after treatment, said area having multiple storage layers;ii) providing a handling means adapted to move the piece of timber on and off the handling means move it vertically on the handling means and move itself and the piece of timber it is carrying between specified locations;iii) providing a storage area where the piece of timber is storable both before and after treatment, the storage area being provided on a plurality of levels each level being accessible by the handling meansiv) providing apparatus for treating the piece(s) of timber including tankage for storing the chemical and pumping means to pump the chemical from the tankage into the treatment apparatus and return unused chemical back to the tankage after treatment;v) providing a control means to specify and monitor the location(s) for the piece of timber throughout the process, to control the movement of the handling means between the specified locations, to control the operation of the treatment apparatus and of the chemical pumping means.

10. A method of treating a piece of newly cut timber with a preservative; in combination with an apparatus for the handling, storage and treatment of timber, as claimed in claim 9, wherein the piece of timber is bundled with others to form a pack of timber for treatment

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