Fixed joints widely used in mechanical engineering are divided into two types: detachable (performed mainly with the help of threaded fasteners - bolts, screws, studs and nuts) and one-piece (performed by various types of rivets, welding, soldering, gluing).
Threaded and riveted joints are widely used in all branches of engineering, and they account for up to 35% of the total labor intensity of assembly work. The range of used fasteners is large and tends to grow. This is due to the fact that the creation of new progressive products, usually more expensive, does not exclude the possibility of using traditional cheap fasteners (bolts, screws, nuts, rivets, washers) in simple light-loaded assemblies that guarantee the required consumer qualities of machines. For example, the US industry produces more than two million types of fasteners, including more than 50 thousand standard (according to US terminology), for a total amount of several billion dollars a year.
The classifier of state standards refers fasteners for general machine-building use to the GZ group, which includes the following classes: G31 - bolts; G32 - screws, studs; GZZ - nuts; G34 - rivets; G36 - washers, cotter pins; G37 - pins; G38 - other industrial hardware. At present, many types of progressive fasteners have been developed and mastered in various branches of the machine-building complex, which are not in the State Standards Classifier. A variety of fasteners in terms of design, technological, functional and other features makes it difficult to exhaustively classify and describe them. However, all fasteners can be divided into five groups. The classification is based on one of the most characteristic features that determined the name of each group, namely: fasteners for mass use; high-strength threaded fasteners; fasteners for one-sided setting and shockless riveting; fasteners for high-resource and tight connections; fasteners for joining polymer composite materials.
The conditionality of the proposed classification lies in the fact that in each group there is a certain range of fasteners that can be attributed to another group. For example, in the group of fasteners for one-sided setting and impactless riveting, some designs of bolt rivets are designed for high-life joints or for joints of composite materials. At the same time, each of the groups includes fasteners of several classes according to the State Standards Classifier. For example, the group of high-strength fasteners includes classes of bolts, screws, nuts, and the group of high-strength fasteners includes classes of bolts, rivets, etc.
However, the proposed classification allows designers and technologists to relatively easily understand a wide variety of fasteners and take into account specific features them in the design and development technological processes assembly of detachable and one-piece connections, and will also assist specialists involved in the design and organization of specialized production of fasteners.
Correctly naming a fastener is often very difficult. What is this? Bolt or screw, anchor or dowel. Given the wide variety of this class of products and the complexity in their correct name Let's turn to GOST, which regulates the names and terms.
Below are some of the most commonly used terms and definitions in accordance with GOST 27017-86 for fasteners and their structural elements.
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A fastener in the form of a rod with an external thread at one end, with a head at the other, forming a connection with a nut or a threaded hole in one of the connected products. |
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A fastener for forming a connection or fixation, made in the form of a rod with an external thread at one end and constructive element to transfer torque to another. Note: The structural element of the torque-transmitting screw may be a slotted head, a knurled head, or, in the absence of a head, a slot in the end of the rod. |
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A fastener in the form of a rod with an external special thread, a threaded conical end and a head at the other end, forming a thread in the hole of a wooden or plastic product to be joined. Note: The special thread has a triangular pointed profile and a large root width compared to the width of the tooth. |
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Fastener in the form of a cylindrical rod with external threads at both ends or along the entire length of the rod. |
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Fastener in the form of a cylindrical or conical rod for fixing products during assembly. |
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A fastener with a threaded hole and a structural element for transmitting torque. Note: A structural element of a nut for transmitting torque can be a polyhedron, knurling on the side surface, end and radial holes, slots, etc. |
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A fastener with a hole placed under the nut or head of a bolt or screw to increase the bearing surface and/or prevent them from self-loosening. |
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A fastener in the form of a wire rod of a semicircular cross section, folded in half to form a head. |
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Fastener in the form of a smooth cylindrical rod with a head at one end, which serves to obtain a permanent connection due to the formation of a head at the other end of the rod by plastic deformation. |
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A bolt whose smooth shank diameter exceeds the nominal thread diameter. |
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Bolt, the head of which is made in the form of a movable part of the swivel joint. |
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A bolt, the diameter of the smooth part of the rod of which is determined from the condition of ensuring the shear operation of the connection. |
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Bolt with a special shape of the head, which is used to fasten the equipment to the foundation. Note: The special shape of the head may represent the extended legs of the slotted part of the rod, the bent part of the rod, etc. |
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A screw whose smooth shank diameter is smaller than the inside diameter of the thread. |
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A screw that forms a special thread in the hole of one of the plastic or metal products to be joined. |
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Self-tapping screw with drill shape end. |
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A screw with a specially shaped end used to fix products relative to each other. Note: Special end shape can be cylindrical, conical, flat, etc. |
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Cylindrical pin with longitudinal groove length, made of spring steel. |
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Hexagonal nut with radial slots for the cotter pin on the side of one of the end surfaces. |
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Hexagonal nut, part of which is made in the form of a cylinder with radial slots for the cotter pin. |
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Nut with spherical and flat end surfaces and blind threaded hole. |
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Nut with flat protrusions for torque transmission. |
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Washer with a flat bearing surface. |
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A split round washer, the ends of which are located in different planes, which serves to prevent self-unscrewing of fasteners during its elastic deformation under load. |
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A washer used to prevent self-unscrewing of fasteners using structural elements. Note: The structural elements of the washer are paws, socks, teeth, etc. |
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Rivet with a rod of tubular section. |
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A rivet, the end part of which has a tubular section. |
Elements of fasteners
Kernel. Part of a fastener that enters directly into the holes of the products to be joined or is screwed into the material of one of them.
Fastener head. A part of a fastener having a rod that serves to transmit torque and (or) form a supporting surface.
Bolt head. The smooth part of the shaft of a bolt, cylindrical, oval or square, directly adjacent to the head and used to center the bolt or prevent it from turning.
Fastener collar. A protrusion on the bearing surface of a polyhedral nut, bolt head or screw, made in the form of a cylinder or a truncated cone with a diameter large diameter their circumscribed circle.
Supporting protrusion of the fastener. An annular protrusion on the bearing surface of a polyhedral nut or bolt head whose diameter is less than the spanner size.
Note: Wrench size refers to the distance between opposite faces of a polyhedral nut or bolt head, screw, measured in a plane normal to their axis.
Fastener slot. A recess of a special shape in the end of the head of a bolt, screw or screw, in the end of a headless set screw, along the generatrix or in the end of a nut.
Note: The shape of the slot can be hexagonal, cross-shaped, in the form of a through or blind slot, etc.
Bolt spike. A protrusion on the bearing surface of the bolt head that serves to prevent it from turning.
The mustache of the bolt. A protrusion on the bearing surface of the head and shaft of the bolt, which serves to prevent it from turning.
Gimlet. The threaded, tapered end of a screw used to cut a thread in a wood or plastic product to form a joint.
GOST 27017-86 fully complies with ISO 1891-79 and should be used in conjunction with GOST 11708-82 “Thread. Terms and Definitions". GOST 27017-86 establishes terms and definitions for fasteners for general machine building applications. Standards establish only basic terms. Today, when new types of fasteners appear in Russia, the process of the formation of terminology is observed, strictly speaking, this is a constant process. The desire of market participants to avoid discrepancies in the names is quite natural.
Interstate standard GOST 27017-86 fully complies with ISO 1891-79 and should be used in conjunction with GOST 11708-82 “Thread. Terms and Definitions".
Bolt- a fastener with a metric external thread in the form of a rod or cylinder, with a head on the opposite end. The bolt head can be hexagonal, cylindrical - imbus bolt, or spherical - furniture bolt. Bolts form a connection using a nut or a prepared threaded hole in the product to be joined. Bolts come with full or partial threads.
Screw- one of the fasteners designed to form a connection and fixation. It is made in the form of a cylinder with an external thread and a structural element on the other, to transmit the translational movement of torque. Heads come with a spitz, knurled or just a slot in the end of the rod in the absence of a head.
Screw (Wood screw)- a popular fastener, in everyday life it is called a self-tapping screw. It has the form of a pointed, conical rod with an external special thread, and a head at the other end. The screw thread has a large root width compared to the width of a tooth with a triangular pointed profile. A thread is formed in the hole of the wooden or plastic product to be connected by screwing.
Hairpin (Stud)- a fastener in the form of a rod or a cylindrical rod with an external thread cut along the entire length of the product or only at the ends on both sides.
Pin- a special fastener having the form of a cylindrical or conical rod. Designed for fixing various products during the build process.
Nut- a fastener with a metric threaded hole. For a constructive transmission of torque, nuts can be multi-sided, hexagonal, knurled on the side surfaces, with a slot, end and radial holes, etc. The design of the nut can be different: cap, extension nut (coupling), mustache, etc.
Washer- type of fastener, a product with a hole placed on the head of a bolt, screw or nut to increase the supporting surface of the fastener structure and prevent self-unscrewing.
Split pin- a special fastener is a form of a wire rod of a semicircular cross section, folded in half at the bend to form a head.
Rivet— fastener smooth cylindrical shape in the form of a rod with a head, used to obtain a permanent connection, forming a head at the opposite end of the rod through plastic deformation.
Hardware- abbreviated phrase "metal products". The concept of Hardware, combines a very wide range of different goods obtained and made of metal. Conditionally divided by purpose: general purpose and industrial.
General purpose hardware- metal products used in Everyday life: scissors and knives, agricultural items: pitchforks, shovels, rakes, various saws, hacksaws and much more.
Industrial hardware- metal wire steel ropes, steel tape, nails, metal mesh, spring washers, cotter pins, crutches and rivets used in railway construction, railway rails, telegraph hooks.
fasteners- this is a type of product that allows you to fasten parts together. The more durable the material from which the various fasteners are made, the strength and durability of the product as a whole depends.
In general, such a concept as fasteners appeared long before the reckoning and our birth. For example, historians and archaeologists say that the first nail was not metal at all, but from fish bone, sometimes from plant thorns, or simply carved from hardwood. By the way, the original building fasteners were wooden and at the same time quite strong, as evidenced by the structures of Kizhi that have survived to this day and still amaze tourists with their fortress. At the same time, up to the 15th century, inclusive, all threaded connections made individually, by hand. At the same time, the bolt and nut were quite expensive and one nut fit only one bolt. Bolts and nuts, as the most effective and time-tested fasteners in the form of a bolted joint, became widespread along with the development of electrical metalworking.
The main types of building fasteners and fasteners indispensable in the construction of buildings and repair work in the premises.
Construction fasteners- fastener direction used in construction to connect building structures and various structures. This group includes such fasteners: self-tapping screws, bolts, screws, anchors, studs, nuts, clamps, couplers, nails, screws, dowels, screws, cotter pins, washers and similar products.
Metric fasteners- these are fasteners of a product that have a thread pitch of a certain size (thread pitch is a rule for determining a particular distance between any two points). This type of fastener includes bolts, nuts, screws, studs.
Stainless fasteners has a high degree of corrosion resistance and thus has an advantage over other types of fasteners. Corrosion resistance under adverse conditions for stainless fasteners is much higher, in addition, it perfectly resists oxidation in alkaline, acidic environments, and in chloride solutions.
Thanks to long terms hardened fastener service of stainless steel, they are classified as high-strength fasteners. High strength fasteners one of the types of machine-building fasteners, so called because it can withstand more significant loads and has a strength class of 8.8, 10.9, 12.9, does not lose its strength characteristics at high temperatures.
Anchor- a fastener of the category of building fasteners, there are varieties: anchor bolt and anchor nut. The anchor is able to stay inside foundations or a solid wall, (strong, inelastic, non-fragile construction). Designed for fastening construction and other equipment as well as various designs. Anchors are usually used in all construction subjects, from dams, nuclear power plants, to a typical building, inclusive.
Classical dowel used for fastening any parts in a solid, non-fragile and durable wall or ceiling panel. The principle of fixing the dowel is a thrust during installation from a screw or screw, which causes a holding force of friction.
clamp- another type of fastener. Clamps are mostly made for connecting any types of pipes made of metal and plastic. Plastic clamps are used for fixing less durable material than metal clamps, however, they provide greater pipe mobility.
Modern construction rigging makes it possible to choose fasteners for various kinds construction works. Such a type of rigging as an eye nut and an eye bolt are used to organize the lifting and movement of goods during lifting and rigging operations. Steel rope or wire rope is used for lifting weights in construction, these items are important detail the operating load-lifting mechanism, both for manual hoists, and for cranes. The chain is also one of the types of rigging. Steel chains are applied in various lifting mechanisms, from manual to cranes. Steel chains, like steel ropes, are used to lift and move loads. for various purposes and designs.
Each fastener is made for specific purposes, so there are a great many types of fasteners, because fasteners are developed and used for a specific material and from specific parts. For example, using certain types of fasteners, you can connect metal to drywall, metal to metal, metal to gypsum fiber, and metal to wood.
Alternative types of connections have both advantages and disadvantages. For example, the so-called "liquid nails" - due to the ease of fastening, it is really easy to connect the parts together. However, what is glued together cannot last happily ever after. Glue - has a chance to peel off in one day, that's why it's glue! Fasteners or hardware has not been canceled!
Fasteners, otherwise called hardware, are one of the most widely used parts. Everyone knows what fasteners are and for what purposes they are used.
Their importance during construction work and in the economy can hardly be overestimated. The term "hardware" arose from the abbreviation of the phrase "metal products".
Fasteners are of two types: detachable and one-piece. The production of fasteners is constantly growing, and the variety of fasteners used is very wide. The reason is that these details are an indispensable attribute of any development in the field of mechanical engineering. The standard of fasteners is regulated in the GOST document “Fasteners. Terms and Definitions. GOST 27017-86”.
Let's take a closer look at what types of fasteners are.
Anchor
Anchor is a fastener designed to connect structures and products. And it is also customary to call a part that is partially concreted into any structure.
Types of anchors:
- ceiling;
- driving;
- wedge;
- frame;
- with a half ring;
- with ring;
- with nut.
These parts are united by the function performed - fasteners. So, a drop-in anchor with internal thread and a wedge-shaped wedge is needed to fasten materials and equipment to brick or concrete. Such an anchor is mounted simply: it is installed in a hole that has already been drilled earlier. The radius and depth of such a hole are selected based on the dimensions of the anchor.
The wedge anchor is used for fast fastening in concrete, a common material for structures such as laths, profiles, dropped ceilings. This type of anchor is often used to secure heavy equipment to solid foundations. To install a wedge anchor, a hole is drilled in concrete, where the anchor is hammered with a hammer, after which it is tightened with a nut. Ceiling anchors made of galvanized steel fix metal profiles, facades, railings, gratings, on a concrete or stone base without cracks.
The frame anchor is designed for fastening frames and door frames from wood and metal to a brick or concrete base.
Bolt
Bolts - cylindrical metal fasteners with a metric external thread and a head at one end, usually designed for nuts. The head of the bolt may be shaped like a hexagon, a cylinder, or a sphere. Bolts allow you to create a connection using a nut or a pre-made threaded hole in the part to be joined.
A stepped bolt is distinguished by the fact that the diameter of its thread is smaller than the diameter of the smooth part. The head of the foundation bolt has special form, which helps to fix the equipment directly to the base.
The most widespread was a bolt with a hexagon head for a wrench. Bolt sizes may vary.
A fastener such as a bolt is usually inserted into a pre-made through hole of the parts to be fastened, then a nut is screwed onto the thread, and the parts are tightened with a wrench. The force of friction allows you to achieve fixation of the connection. To transfer part of the load to the bolt, the maximum accuracy in the manufacture of the rod and the hole for it in the details is required. To prevent parts from deforming, washers are placed under the bolt head and nut. Bolt sizes allow you to find the right fastener for any application.
Nail
The material for the manufacture of ordinary nails is steel and steel wire. The marking of nails includes two numbers: the first is the diameter of the rod, the second is the length of the rod in millimeters. The head of the nail is both smooth and corrugated. Screw, club and corrugated nails are distinguished by the presence of helical, longitudinal and transverse grooves, burrs or dents on the rod. Such nails have more resistance to pulling out.
Hardened steel nails can be driven into brick and concrete walls. True, when working with them, it is necessary to take into account their increased fragility. For fastening to rigid bases, roofing, wallpaper, plaster nails are used. They are produced with a flat, wider head than ordinary nails, and a shorter shaft. In aggressive environments, copper nails can be used, which are almost not subject to corrosion, as well as galvanized or alloy steel.
The operation of hammering nails has its own specifics. In order for the nail to be hammered with high quality, a number of requirements must be followed.
To prevent dents on the parts during the driving in of nails, you need to use a countersink. In order for the bond to be strong, the nail shaft must go 2/3 of the length into the lower fastened part. When hammering small nails, it is best to use auxiliary devices. To make the joints of the parts to be joined stronger, it is better to hammer the nail at an angle. When using thick nails, in order to avoid splitting the board, you need to slightly blunt their sharp end. If it is planned to hang any load on the nail driven into the wall, it must be hammered not perpendicular to the wall, but at an angle from top to bottom.
The nail that has passed through must be carefully bent, resorting to the help of a trihedral file. In order not to damage the surface of the parts when pulling out nails with pliers, you need to use a plate that is placed under the pliers, reducing the pressure on the part. If further dismantling of parts is planned, it is preferable to use screws rather than nails.
In some cases, liquid nails are used to fasten products. They are made from polymer materials and rubber. Liquid nails are able to provide sufficient fastener strength no worse than metal ones. One drop of nails of this type can withstand a force of 50 kg. But their main advantage is the preservation of integrity decorative surface. Application area liquid nails very wide. They are used for gluing to a variety of wall and wall surfaces. ceiling panels, drywall, chipboard, fiberboard, wood, cardboard, ceramics, stucco decorations, glass, metal and many other materials.
When buying liquid nails, you need to be careful. Different grades of this material have a certain degree of adhesion.
Liquid nails are advisable to use:
- at high humidity premises;
- for temperatures not lower than -10 0 C.
For example, neutral nails are harmless because they are based on a water solution. However, they cannot glue metal. They do not like and sub-zero temperatures. nails on organic solvents possess the increased speed of a setting and maintain temperatures to -20 °C. Their disadvantage is the presence in the composition of volatile harmful substances. Within 5 days after application, they publish bad smell. The setting of liquid nails occurs within 15 to 30 minutes, depending on the brand. However, they completely polymerize only after a day.
screws
In order for the screws to perform their function as reliable fasteners to the fullest, it is necessary to choose their size and type correctly. So, screws are fasteners for wooden structures. Their rod tapers towards the end and performs the function of a drill. This type of fastener cannot be hammered in like nails - they are twisted completely. Before using screws small size first, a puncture is made with an awl. Large screws will be easier to screw if you first make a slightly smaller diameter hole with a drill.
The screws are used to connect metal structures. The head of the screw contributes to the pressing of the parts to be joined, and its shape is chosen so that the screw can be easily tightened using wrench or a screwdriver. Screw heads can be hexagonal, semicircular or countersunk. The flat end of the screw has a chamfer to prevent thread entry.
A screw is a fastener that is screwed into a threaded hole. In some cases, a hole is drilled at the end of the screw for the use of a cotter pin - a wire rod with a semicircular cross section, bent almost in half. The cotter pin serves to prevent spontaneous unscrewing of the fastener.
Often a washer is installed between the part and the nut, the inner hole of which allows the screw shaft to pass into it. If the screw is rusted, a striker or special crimps are used to remove it. Heating the nut can often help. gas burner or blowtorch. If open fire is forbidden for any reason, you can use a red-hot iron rod or a large soldering iron.
screw
A nut is a type of fastener with a threaded hole inside. The most widely used galvanized nuts. The shape of the nuts is hexagonal, round with a notch, square, with protrusions for fingers. The main purpose of a nut is to connect parts using a bolt.
Types of nuts:
- hexagonal;
- square;
- "lamb";
- flanged with a groove for a cotter pin in the form of a cap;
- T-shaped, with plastic insert.
It is also worth noting that the nuts are also divided according to the strength class in accordance with the bolts with which it is used.
Dowel
Dowels are used for fastening in solid wall bases. The fastening of the dowel is based on the principle of friction, which occurs due to the expansion of the fastener during installation with the occurrence of a holding force. The dowel is able to withstand large static loads. During dowel installation, the fasteners are destroyed during the pulling process. The dowel is made of polymers. Their physical and mechanical properties can vary greatly depending on various factors. These are the characteristics of the filler, the ratio of components, the parameters of the binder. The disadvantages of polymers include low heat resistance, a tendency to deformation under load, and aging.
Only screws properly matched to the dowel can withstand the maximum load. They must have maximum allowable length and a diameter corresponding to the length and thickness of the dowel. When using other fasteners, the thread profile is of great importance, since it determines the expansion effect. The use of self-tapping screws and screws for fixing drywall sheets is not recommended.
A number of manufacturers are engaged in the manufacture of dowels that allow the installation of screws with metric threads. The greatest locking is achieved with a dowel in concrete, stone and other solid hard materials. It should be borne in mind that the hole for installing the dowel must be drilled in accordance with the recommendations for depth, diameter and distance from the edge. As a result of drilling a hole, cracks or chips should not occur. The hole must also be cleaned of debris and dust.
Among the proposals of manufacturers, one can find varieties of dowels with an increased length, necessary for soft and hollow materials. When installed in such a base, fixing can be achieved by fixing the internal stop of the parts. For insertion occurring in hollow materials, anchoring is based on a combination of friction and internal stop. It is necessary to take into account all the factors that determine the reliability of fastening in all their relationship.
Rivet
Detail such as a rivet combined type, consists of an aluminum body and a rod made of galvanized steel. This design is the most common. The purpose of a rivet is to join two or more surfaces of thin sheet. The need for a rivet arises in cases where a permanent connection is required using a power tool, when access on the side of the closing head of the rivet is limited or closed.
There is also an exhaust rivet nut - a fastener that is widely used in mechanical engineering and electronics. The rivet nut is designed to create threaded connections in metal materials and other thin materials of high strength. Among rivets, steel rivets are the most durable. Steel rivets are protected from corrosion by galvanizing.
Threaded rivets differ from ordinary exhaust rivets in that they not only connect sheet materials, but also have an internal screw thread.
High-quality threaded rivets are installed in places where it is difficult to reach using such a simple tool like a riveter.
Since the choice of lengths and diameters of rivets is very wide, the search for the best one for the task must be carried out by marking on the product.
self-tapping screw
To fasten metal parts of small thickness to wooden or plastic surfaces, self-tapping screws with frequent threads are used. Insulation mount, fiberboard, wooden parts produced by self-tapping screws with a large thread. Having a tip in the form of a drill, it is able to independently make holes in the parts to be fastened. If the self-tapping screw is screwed into a hole drilled in advance, self-tapping screws with a sharp tip are used. A universal black self-tapping screw is used to fasten drywall sheets with tin profiles. Universal self-tapping screw white color used for fastening steel, plastic and wooden materials. Self-tapping screws are the most widely used fasteners for wooden structures.
Washer
The puck is made from steel tape cold rolling. It is a round plate with an internal hole and is used to increase the strength of bolted joints by placing it under the bolt head or nut. Thanks to the rivet, the clamping surface of the parts to be fastened increases, which makes it possible to protect the surfaces to be joined from deformation when the nut is tightened.
Hairpin
Stud - fastener, which has the form of a cylindrical rod, which has an external thread cut either along the entire length or at the ends. Such a connection is used if none of the materials involved in the connection has a thread. Further, the connection is fixed by means of a nut, sometimes supplemented with a washer. The use of studs as a fastener harms appearance products.
Screw
A screw is a fastener in the form of a rod with an external thread with a conical tip and a head at the other end. It has the ability to create new threads in plastic or wood products. Screws - hardware, fasteners, which have found the widest application in construction and decoration works. They also cannot be replaced during installation. drywall sheets on a metal or wood frame.
Various types of screws are also used in roofing, facade work to connect metal sheets. The roofing screw has a hexagonal head and is supplied with an ordinary washer and a sealing washer, the latter being made of weather-resistant rubber. This type of screw is dyed and available in 18 colors, helping to give the building an aesthetic appearance.
Each type of fastener is made to perform certain functions. This explains the wide variety that fasteners delight. The price of hardware is different and can range from 2-3 rubles to several thousand rubles apiece, but they are often sold in kilograms.
Fasteners are designed for specific materials and parts. So, using certain types of fasteners, you can connect metal with drywall, two metal products or metal with wood details.
When carrying out construction, repair and other works, in mechanical engineering ..., in almost any production it is impossible, or extremely difficult, to do without the use of various kinds of fasteners. Metal fasteners are a guarantee of reliable connection of individual parts to each other. The most common and popular fasteners are considered to be hardware - metal products.
Fastener classification
1. Anchor fasteners are technically complex steel products that carry high loads (up to 5 tons).
2. Screws and self-tapping screws are the most commonly used and easy-to-use type of fastener. It has a very wide distribution and application.
3. Metric fasteners are the most reliable and common type (nuts, bolts, washers, etc.)
4. Dowels - mainly products made of propylene or nylon. Used in conjunction with screws or self-tapping screws.
5. Nails - made of metal for attaching parts to wooden bases.
6. Tapes perforated with holes - made from sheet steel (corners, perforated tape ...). Often used in the construction of wooden houses.
7. Rigging fasteners - are used for fastening and moving various loads (cables, chains, carabiners ...).
Anchor fasteners
There are several types of anchors:
- driving anchor - a metal sleeve. Threaded on one side, cut on the other side. There is a wedge inside, which, when hammered (mainly into concrete), securely holds the mounted structure;
- wedge - also used in concrete and natural stones. Clogged and additionally twisted with a wrench;
- expanding - a special expanding mechanism opens inside the base;
- chemical anchor - a pre-prepared hole is filled chemical composition and insert the anchor rod.
Electrical fasteners
Some types:
- dowel-bracket for round and flat wires;
- cable tie;
- universal wire clamp;
- fixing flat and round wire;
- clamps;
- mounts for corrugated pipes, PVC and cables.
Self-tapping screws and screws
Divided by type of head:
- hexagonal;
- semi-cylindrical;
- secret;
- hemispherical;
- with a cross slot.
The types of tips differ:
- with a sharp end;
- in the form of a drill.
Depending on the application, they are divided into:
- for connecting wooden parts;
- for connecting metal parts;
- roofing.
Protection of fasteners by electroplating
Serves to increase service life. Anti-corrosion coating can be:
- copper;
- tin;
- zinc;
- nickel;
- cadmium.
Almost all human life is permeated with ties: social, family, moral, business. Even everything that surrounds a person is created thanks to strong ties. These connections are held by fasteners. IN modern house in construction, countless such elements are used.
What is the fastener for?
Fasteners are designed to connect and hold connected various details one whole. It ensures the safety of structures, their integrity and durability.. Thanks to these elements, everything around becomes durable and comfortable. The modern market is able to offer a variety of types of elements: nails, nuts, bolts and much more.
Variety of fasteners
There are thousands and thousands of names of fasteners, taking into account the material, size, type and purpose. Basically, all this diversity can be divided into several large groups:
- Furniture: drills, drills, consumables;
- Hardware products: nuts, rivets, washers and bolts;
- Special: products for fixing ventilation systems, electrical equipment, plumbing systems;
- Construction: screws, dowels, nails, anchors. They are used most often. This group has found wide application in home life.
In stores you can find products of domestic and foreign production. Today, professionals give preference to such brands as ABC, Fisher, Bralo (Spain), Sormat (Finland), Wurth (Germany), Omax (USA). It's over expensive views products of high quality. Most of of the proposed range - Chinese, Thai or Taiwanese production. This fastener is more affordable and is quite suitable for minor home repairs. But for serious work, it is hardly suitable.
Nails
Everyone knows what nails are. They firmly entered the life of a person and occupied an important place in it. Nails are divided into:
- Construction with a flat corrugated or smooth cap;
- Special ("crutches", "doublet");
- Slate nails;
- Corrugated, screw or ring nails for fixing the roof.
Screws, screws, screws
All these types of fasteners look like threaded rods with a head. Their scope is decoration, facade and roofing, installation, assembly of furniture. The difference between screws, screws and self-tapping screws is that in order to use the screw, you need to drill a hole and cut a thread in it. When working with a screw, this is not necessary. And when working with a self-tapping screw, there is no need to drill a hole at all.
There are many more types and types of fasteners. For almost every type of work, practical and most convenient fasteners have been created.
