Design of SWP plant

Contents

Summary

Introduction

1. History of SWAps and production technology

1.1 History

1.2 Properties of approximate chip boards

1.3 Application of approximate chip boards

1.3.2 SWA as an independent structural element

1.3.2 Bearing and enclosing structures based on OSB

2. Justification of construction and organization of SWAp production

3. Raw materials and fuel and energy base of the enterprise

4. Purpose and composition of the enterprise

5. Production capacity and product range of the enterprise

5.1 Workshop capacity

6. Operating mode of the enterprise

6.1 Shop operation mode

6.2 Equipment Utilization Factor

7. Process Part

7.1 Process

7.2 Selection and calculation of main process equipment

7.2.1 Calculation of main equipment quantity

7.3 Plate Storage Warehouse Calculation

7.4 Calculation of raw material storage area

8. Mechanical equipment

8.1 Main Equipment

9. Storage and transportation of OSB plates

10. Product Quality Control

10.1 Technical control

10.2 Laboratory control

11. Labour organization and enterprise management system

11.1 Organization of work and maintenance of workplaces

11.2 Scientific organization of labor

11.3 Working and rest conditions

11.4 Basic management functions and management structure

12. Master Plan and Transport

13. Architectural and construction solutions of the enterprise

13.1 Construction Specification

13.2 Space planning solutions

13.3 Design Solutions

13.4 Roof

14. Automation of production processes

14.1 Process Automation

14.2 Automation of the furnace and dryer drum

14.2.1 Management

14.2.2 Regulation and Control

14.2.3 Protection and Alarm

15. Enterprise Life Safety

15.1 Life Safety

15.2 Safety when working in woodworking enterprises

15.3 Fire Safety

16. Economic calculation

16.1 Cost of production

16.2 Calculation of profitability

16.3 Calculation of planned profit

16.4 Key Technical and Economic Indicators

16.5 Investment Volume

16.6 Payback Period Conclusion... List of used literature

Summary

Lumber enterprises, in addition to the cut lumber itself, periodically invent new ones. One of the materials of the new generation is SWP - oriented chip board (the abbreviation in Latin is also used - OSB, orientedstrandboard).

The first OSBplate was produced in 1982 in Canada. The OSP is a multilayer (3-4 layers) sheet consisting of relatively large wood chips glued together with resins. Synthetic wax and boric acid are also added to the OSP. The name "oriented particle" comes from the gluing technology: chips in the layers of the plate have an orientation (in the outer longitudinal, in the inner, respectively, transverse).

SWA is widely used for the manufacture of furniture, skin, packaging (boxes, etc.), load-bearing structures in the premises; lacquered slab is often used for design purposes, and laminated slab is used as a basis for formwork for reusable use in concrete work. In addition, there is a pierced SWP (with machined ends of the "slot" type) used for laying over the surface area.

1. History of SWAps and production technology

1.1 History

Oriented chip plates were invented in Canada in the second half of the 40s of the last century. The birth of SWP technology was the result of the further development of the technology for the production of so-called waffle plates. Waffle plates are outwardly very similar to SWAps and are still used in construction in North America, however, now in much smaller volumes. But waffle plates gained fame precisely as the progenitors of SWAps.

The technology for the production of waffle plates was developed by Dr. James d'Arcy Clark in 1954. James Clark was an environmental scientist and dealt with the problem of recycling low-grade wood in forests in the northwestern United States. The problem was quite acute, since with continuous logging on the harvest of pine, spruce and larch there was a lot of aspen.

D. Clark was well acquainted with the technology for the production of wood fiber and particle boards. And he decided to create a technology that would allow you to make wood boards from aspen. It was only necessary that these plates had some kind of feature and were of interest to the market. The only type of wood slabs that could be used in construction at that time was plywood, which was made from Douglas fir. The market was constantly high demand for it. D. Clark tried to find a way to make aspen plates with improved strength characteristics so that they could at least partially replace plywood. To do this, it was necessary to maximize the strength of aspen wood fibers.

And so, when D. Clark once sharpened a pencil with a sharpener, he came up with the idea: "What if you make the chips thin and wide, carefully cutting it along the fibers?" To do this, it was possible to modernize the chopping machine, which was used in the production of chips for CPD.

In the 50s of the last century, particle boards (chipboards) were already produced, previously sorting chips and using a larger one on the inner layer, and a smaller one on the outer layer of boards. Wood fiber boards (FIs) were also made from fiber, which was obtained by grinding wood. But until that moment, no one had ever even tried to make slabs from thin wide chips.

So, you had to come up with a new design chopping machine, turning it into a chip machine. The basis was taken as an ordinary pinch machine, but the principle of its work was slightly changed. The chip machine was not only to chop the wood into pieces of a given length, cutting the fibers across, as the chopping machine does, but also to strut thin layers of wood along the fibers of the log. It was possible to increase the percentage of rectangular chips with optimal dimensions: width 50 mm, length up to 70 mm and thickness 0.7-0.8 mm.

Otherwise, the technological process copied the production of CPD. It was only necessary to adapt the technology of drying and salting larger chips, as well as the process of molding the chip carpet.

In the mid-50s of the XX century, the first waffle plates were born. The test results exceeded all expectations. Waffle boards were much stronger than particle boards, and could indeed be used in construction.

Also Armin Elmendorf in the laboratory in PaloAlto (California) dealt with issues of development of the production technology of wafer plates. In the late 1950s, scientists in Europe, in particular Dr. Clauditz in Germany, became interested in this technology.

First production

After 7 years, in 1961, several businessmen from Saskatchewan (Canada), wanting to use cheap aspen, which grew abundantly in northern Canada, bought a patent from James Clark. A little later, the Weiswood Limited company was organized, which began to produce waffle plates in industrial volumes. A waffle plate plant was built in Hudson Bay, in the northern forests of Canada. The authorities, wanting to strengthen the economy of a low-income agricultural province, provided the enterprise with an excess of very good wood.

In 1963, the shares of the Weiswood plant, then owned by the Saskatchewan government, were sold to McMilan Blaidil Limited, the largest pulp, lumber and plywood manufacturer in Canada at that time. McMilan Bloidil needed a new wood product with a lower cost than plywood. This, according to the company's management, was supposed to strengthen their position in the construction plywood market and increase annual turnover.

McMilan Bloidil had a well-developed sales system throughout Canada, and it was also possible to carry out all the necessary product tests to obtain such necessary construction certificates. This allowed the company to launch the production of waffle plates and successfully bring it to design capacity. The plant in Saskatchewan, by the way, was equipped with a 14-span hot press, which allowed the production of 1220x4880 mm plates. The press, dryer, chip mixers and molding line were retrofitted equipment from the CPD production line. Soon, AspenitTM plates achieved significant success and universal recognition in the market.

The material was actively sold for the construction of storage facilities for various purposes, livestock farms, garages, utility rooms. In addition, AspenitTM was used in the construction of protective fences, temporary quick-dismantling structures, the construction of granaries, in the production of packaging and billboards. McMilan Blaidil Research Group has developed a tongue-and-tongue joint of slabs for siding, concrete formwork and flooring. The product quickly gained recognition among architects, engineers, designers and builders. The market price of AspenitTM was lower than plywood, and this gave waffle plates a serious advantage.

Further development

In 1973, a second waffle plate factory was opened in Timmins, Ontario. The goal of investors was to process the cheap aspen of coniferous forests of the north of the province. The new Weiferboard Corporation company organized the sale of its products through the Candian Forest Products company. The product entered the market under the brand name "MailitTM." Gradually, the perception of waffle plates began to change.

During the 70s of the last century, several more wafer plate plants were built in Canada and the first such plant was launched in the northern United States.

Sum of technologies

In the mid-70s of the twentieth century, the idea was born to divide the chip embankment in the production of waffle plates into several layers. And orient chips in each of these layers in mutually perpendicular directions. In addition, in order to increase the strength characteristics of the plate, they decided to change the chip geometry. It was decided to make longer and narrower chips, compared to what had been made before. So, the concept of production of a new type of slab materials, which is known to us today under the name SWP, was gradually developed.

The first plant, which began to produce real oriented chip boards, appeared in 1982, although they began to orient chips in the production of waffle boards in the late 70s.

In fact, oriented chip boards are second-generation waffle boards. The first real OSPplate was produced in Alberta (Canada) at the Edison SWP plant. The plant then belonged to Pelican Somils Limited. The first product tests showed that as a result of the improvement in technology, the physical and mechanical characteristics of the new material were equal to the characteristics of softwood plywood. This allowed the Edison OSP plant to position oriented chip plates on the market as a complete analogue of plywood and higher-class material than waffle plates.

The new material was called OSP (oriented strand board - OSB), since it was distinguished from all known wood boards by the size of the chips and its orientation in the structure of the plate. OSP chips were narrower and longer compared to wafer board chips: the average chip size was 25x150 mm. Each plate consisted of 3 layers. All chips in the layer were parallel to each other and perpendicular to the chips in adjacent layers. Due to the orientation of chips in each of the layers, SWAps have acquired unique properties, which soon opened a number of new applications for them.

The technology of chip carpet forming in the production of SWP has undergone several changes. The orienting head of the chips of the outer layer is something very similar to farm harrows. It consists of a series of round disks that direct the chips falling through them, aligning it parallel to the direction of movement of the carpet on the conveyor. Guide chip head of inner layer consists of rollers in the form of sprocket with flat blades. Rotating, they align the chips parallel to the width of the carpet and perpendicular to the direction of movement of the conveyor. Dimensions of elements of orienting heads and distance between them are adjusted to dimensions of chips. Adjustment is performed so that chips fall through rotating discs or rollers before they take it out of the orienting head.

Layers with oriented chips are laid on the conveyor moving at the bottom sequentially, one after another. The orientation of chips in layers alternates as follows: longitudinal, transverse, longitudinal. Each layer is formed by a separate orienting head and laid out by a separate forming machine.

The accuracy of chip orientation during chip carpet molding is a very important issue. This is especially the case with the chips of the outer layers. The accuracy of chip orientation in the layers directly affects the strength characteristics of the finished product.

No less problems for engineers caused the task of high-quality and uniform grinding of chips before molding. In the production of slabs, SWP used the same resin that was always used in the production of water-resistant plywood. But how to thoroughly mix the finest chips with minimal damage to it? Thanks to creativity, the issue was soon resolved. In modern chip mixers with glue, the resin is sprayed with a rotating disk. The design of the resin distributor was borrowed from the technology of painting cars. This seemingly simple solution turned out to be a real breakthrough in the technology of salting, which allowed not only to reduce damage to chips during salting, but also to significantly reduce the consumption of resin.

Raw material base

As a raw material for waffle plates produced using the original technology of D. Clark, at first only aspen was used, which was harvested in central Canada and the northern United States. However, in the late 70s of the last century, when the first waffle plate factories appeared in the southern United States, pine wood began to be used as raw materials. In the early 1980s, when waffle plates had already turned into SWAps, and consumption and demand for chip plates began to grow rapidly, white birch, maple, amber wood and yellow poplar began to be used in production. Also, some other types of hardwoods began to be put into production, but only in small proportions. Canadian factories began to successfully produce SWAps from larch and white pine growing in the east of the country. In the west of the country, a plant was built working on a mixture of aspen and black pine (Banksa pine). Some manufacturers began to make chip boards from a mixture of balsamic poplar and white birch.

In the mid-80s of the twentieth century, when the first factories in Europe were opened - in Scotland and France, Scottish and seaside pine species also began to be used in the production of SWPs. One of the last built SWP plants in Chile uses Radiata pine. SWA plants in Asia and Australia operate on raw materials from rubber wood and eucalyptus.

Looking to the Future

Experts predict a great future for SWAps. New Zealand has a research institute dedicated to the development of new wood composites. Oriented chip composites are ranked among the most promising areas. Now developments are underway, which in the near future will allow more active use of SWAps in the furniture industry, in door manufacturing, in especially loaded building structures, etc. So-called online quality control systems are being developed that will allow testing of the entire volume of products in real time. And finally, in the issues of the production and salting of chips, the accuracy of its orientation when moulding a carpet, pressing a chip carpet, there is still a lot of room for research work (4).

1.2 Properties of approximate chip boards

The main properties of the approximate chip boards are:

• high strength - physical and mechanical parameters of OSB are 2.5 times higher than that of CPD (Chip board) and are approximately the same as that of softwood plywood;

• moisture resistance - the material does not break down and retains its strength characteristics when in water for 1 day (swelling coefficient - about 10%);

• easy processing - slabs are easily cut and drilled, can be glued and painted with any adhesives and paints intended for wood;

• fastener retention factor is 25% higher than that of softwood plywood and CPD;

• low level of defects (stratification, knots and voids);

• OSB plate is not susceptible to insect damage.

According to OSB production technology, different types of resins are most often used for the inner and outer layers. An adhesive mixture based on a carbamide-formaldehyde or melamine-formaldehyde resin is used for the outer layer, while a urea-formaldehyde resin is used for the inner layer, but a phenol-formaldehyde resin can also be used. Urea-formaldehyde resin, in terms of good adhesion to wood and their low cost, is currently the most popular product for the woodworking industry. The concentration of resins is from 12 to 14% by weight of the starting composition. All of these resins have high toxicity. But if the first three types of resins, when used in finished slabs of CPD and OSB, release formaldehyde and methanol into the air of the rooms, which are highly toxic substances and are present in the air of the rooms in concentrations that significantly exceed the maximum permissible concentrations of the average daily for atmospheric air and air of the rooms (PDCss), then phenol formaldehyde resin also releases phenol. In modern technologies MDI is used polymeric, for both layers (used for production of polyurethane foams, polyfoams, automobile panels...), and in the name has a prefix - ECO, Green.