SIC 25

Furniture and Fixtures Industry

This group deals with the production of household, office, public, and restaurant furniture. It contains establishments engaged in manufacturing furniture and fixtures. It's industries include:

-Household Furniture
-Office Furniture (except wood)
-Public Building and Related Furniture
-Partitions, Shelving, Lockers, and Office and Store Fixtures (chiefly wood)
-Partitions, Shelving, Lockers, and Office and Store Fixtures (except wood)
-Miscellaneous Furniture and Fixtures

Forming: This major group doesn't deal with material production processes (such as in group 24). Lumber, metal, and plastic are provided to establishments who then form, machine, and assemble these materials into furniture and fixtures. All of the industries listed above use forming processes. Forming in this group is restricted to cold working processes, where the material (metal or plastic) is mechanically worked or deformed cold. Such processes are advantageous because they provide good dimensional accuracy, and good surface finish. There are losses in strength and greater forces are required to cold work, but machining can sometimes be eliminated with proper working.

SQUEEZING is a forming process where the material is forced to compact. It is used to produce features such as sudden tapers, rounded ends, and thinner sections. Common squeezing techniques include:

BENDING requires deformation of the workpiece about a linear axis. It is used to form metal to numerous geometric shapes such as right angles, rounded corners, and tight seams. Typical products from this group produced by bending are metal shelves, filing cabinets, and lockers. Common bending applications include:

SHEARING is a mechanical forming process for metal sheets or plates where material is cut without the formation of chips or the use of burning or melting techniques. Shear forces are applied to produce dislocations along grain boundaries of the material. Common shearing applications include:

DRAWING is a forming process where plastic (permanent) flow occurs over a curved axis. A good way to envision drawing is taking a flat sheet of material and using a punch to push a cup-like shape from the sheet. The materials used for furniture and fixtures include metal and plastic. Some common drawing techniques include:

Machining: All of the industries in this major group use machining processes. Machining deals with removing material (usually in the form of chips) so as to obtain a finished product of desired size, shape, and finish. Machining that does not produce chips is classified as non-traditional machining.

SAWING produces chips or "saw-dust" by a succession of small cutting edges or teeth arranged in a narrow line on a saw blade. Sawing processes in the Furniture and Fixture group range from cutting off sections of wood to notching metal. Saws can be classified into three distinct types; reciprocating, band, and circular.

MILLING is a type of cutting process where a surface is generated progressively as it is fed to a rotating tool in a direction perpendicular to the tool motion. It differs from sawing in that the tool is much thicker than a narrow blade. Milling is often used to produce patterns of lumber, plastic, and metal. Milling is faster than sawing, but it often leaves surfaces that are too rough for many applications.

OXYGEN TORCH cutting uses oxyfuel gas to cut metal, wherein the material is actually melted by the flame. It is by far the most used means of cutting metal. Acetylene, propane, and natural gases, mixed appropriately with oxygen, are used as fuel for the torch.

ARC cutting uses an intense electrical arc to melt metal and force it to flow. Types of arc cutting include; oxygen, air carbon, gas metal, and plasma.

LASER BEAM cutting uses intense heat from a focused laser beam to melt and/or evaporate the metal. Laser cutting devices are used for their ability to make precise cuts with little material waste. It is often difficult, however, to cut thick metal in a laser cutting process.

WATER JET machining removes material through erosion effects of a high velocity, small diameter jet of water. It is commonly used for cutting and slitting of wire, and for cable stripping. Abrasives can be added to the water to handle stronger materials.

SHAPING is the simplest form of machining relative to motion. It uses a single point cutting tool that moves in a straight line across the workpiece. Types of shaping include horizontal push and pull, and vertical cutting. A variety of tool geometries can be used to create many different shapes.

PLANING has the workpiece move past a single point cutting tool (the opposite of shaping). It is a simple form of machining that has its limitations due to slow feed rates and low productivity. It can be used to produce shapes from different tool geometries and reduce thickness of metal, plastic, or wooden pieces when appropriate.

TURNING is a high speed process where the workpiece rotates and a longitudinally fed, single point tool does the cutting. Variations of turning include tapering, facing, and boring. Turning requires the use of a lathe except in some boring operations. Multiple diameter poles and rods are easily produced in a turning process. Typical products in the Furniture and Fixtures group are decorative wooden rods used in staircases.

DRILLING uses a rotating tool with two edges that is pressed into the workpiece to produce a hole or void. Precision holes are required for the ultimate assembly of furniture. Types of drilling tools include; straight and taper shank, deep hole, combination, subland, and spade. Feed rates depend on the type and thickness of the material. Drilling is often followed by counterboring or countersinking to accommodate fastening devices.

REAMING is a process that can only follow a drilling or drilling related process. It uses a multiedged cutting tool (often on the same machine used for drilling) to bring holes to a more exact size. Types of reamers include; hand, machine, shell, expansion, and adjustable. Common drilling machines used for reaming include; upright, radial, gang, deep-hole, and transfer.

BROACHING uses a tool (called a broach) that contains a series of circular, single point, cutting edges around a bar that gradually increases in diameter. This process is unique in that the feed rate is determined by the tool. Types of broaching include; roughing, sizing, and burnishing. Metal is the typical work material for a broaching process.

FILING requires cutting teeth arranged in succession along the same plane on the surface of a file to remove material chips. Types of files include; single-cut, double-cut, vixen-cut, and rasp-cut. Files are also classified by coarseness and construction. Filing is important to furniture industries in easily removing sharp edges that could cause injury in finished products.

ABRASIVE machining uses very small cutting edges that are integral parts of abrasive particles to produce chips from the material. A good example is using sandpaper to smooth a rough surface. Types of abrasives include; quartz, aluminum oxide, silicon carbide, and diamond. Some common types of abrasive processes include grinding and lapping. Grinding uses a wheel of some shape on which abrasives are bonded. Lapping requires that fine particles be embedded into a soft material (like paper) which serves to finish the part. Abrasive machining is limited to small amounts of material removal. However, it can provide extremely smooth surfaces.

ABRASIVE JET machining removes material through the action of a focused stream of abrasive laden gas. Common abrasives include; aluminum oxide, silicon carbide, sodium bicarbonate, and glass beads. AJM is used to debur plastic parts, deflash small castings, and touch up molds. AJM is very cheap and good for difficult to reach areas. It can machine very hard materials, but it has a slow material removal rate. Stray cutting may occur, along with the embedding of particles in the workpiece.

CHEMICAL machining is classified as non-traditional machining in that it doesn't produce chips. It employs some type of chemical reaction (sometimes enhanced by electrical or thermal energy) to remove material. A good example for furniture would be etching metal to produce decorative surfaces. Chemical machining often take the place of processes such as deburring, grinding, and polishing.

ULTRASONIC machining is a material removal process used to erode holes and cavities in hard workpieces. It uses shaped tools and high frequency mechanical motion. Another form of ultrasonic material removal is the stripping of finishes via underwater ultrasonic wave emission.

Assembly: The actual putting together, joining, and additional finishing of components constitutes assembly. Not many processes define a fashion in which parts and components are put together, it's just done in (hopefully) the fastest, most efficient manner. Most furniture requires assembly of numerous parts. Once together, there has to be a means of joining the components.

WELDING is a process where two materials (usually metals) are permanently joined together through localized coalescence. Weld quality and strength depend on a combination of temperature, pressure, metallurgical conditions, and skill of the welder. Welding is used for furniture when weaker joining processes are ruled out, such as in structures for desks and bookcases. Various forms of welding include:

SURFACING is the deposition of a layer of metal or other material upon the surface of some base metal. The layer of material can be applied with nearly all gas flame and arc welding methods. Surfacing is used for decorative and coloring purposes for furniture and fixtures.

MATALLIZING is the surfacing of a base metal by melting and atomizing material in a special torch and spraying the resulting liquid onto a surface. Metallizing is used to protect, harden, reflect, and provide electrical conductivity.

BRAZING is the joining of metal components through the use of heat and filler material whose melting temperature is above 450 degrees Fahrenheit, but below the melting point of the metal to be joined. Common fillers include; brass, bronze, copper silicon, and silver alloys. Brazing is not as strong as welding, but can be used on virtually all metals. Less heat is required than welding, and brazing is good for mass production.

SOLDERING is the joining of metal components through the use of heat and filler material whose melting temperature is below 450 degrees Fahrenheit. Common fillers include; lead alloys and aluminum. Dip type soldering is used extensively when many parts can be joined at once. Soldered joints are weaker than brazed joints, but less heat and effort are required to perform soldering.

ADHESIVE BONDING uses composite systems with several compounds to join two surfaces together. The bonding material may exist as liquids, pastes, solids, tapes, or films. Common types of adhesives include:

Wood can be joined to almost any type of material using the proper adhesive. The surfaces of both components must be clean and dry to insure proper bonding.

MECHANICAL FASTENING requires that a joint be formed by mechanically interlocking or interfering with no fusion or bonding present. Fastener types for wood include integral and discrete. Integral fasteners are machined areas of wood such as tabs and seams that fit into other parts. Discrete fasteners are separate pieces such as nails, bolts, screws, rivets, and wires.

COATING is performed to impart certain properties to wood surfaces such as resistance to weather and wear, different colors, and smoother finishes. Coating is different from curing in that it only deals with the surface of the wood, and that it is usually performed after joining. Coatings can be classified into organic and inorganic types. Common coatings for wood include paint, stain, varnish, and plastic laminations.

Inspection and Testing: Most of the processes already described in the Lumber and Wood Products major group occur at only one point in the overall manufacturing path. Inspecting and testing, however, are performed numerously throughout all processes. It can consist of a simple check to see if a piece is present, or a minute measurement of the surface of a finished part. Inspection and testing tell whether or not a particular process was performed adequately.

DESTRUCTIVE TESTING does not allow for use of the tested part after inspection because it imparts some type of mechanical deformation. An example of destructive testing in furniture products would be stress testing a structural member. This type of testing is done on a sampling basis. Other types of destructive testing for wood products include fatigue, impact, creep, torsion, and shearing.

NON-DESTRUCTIVE TESTING allows for use of the part after inspection. It includes a wide range of optical and mechanical techniques. Mechanical techniques using instruments such as calipers, micrometers, and scales may contact the part, but they leave no significant mechanical deformation. Optical techniques include structured light, triangulation, holography, and interferometry. An example of a NDT application to furniture parts would be testing for the presence and size of a drilled hole.


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