Widely used in mechanical engineering, fixed connections are divided into two types: detachable (made mainly using threaded fasteners - bolts, screws, studs and nuts) and permanent (made by various types of rivets, welding, soldering, gluing).
Threaded and riveted connections are widely used in all branches of mechanical engineering, and they account for up to 35% of the total labor intensity of assembly work. The range of fasteners used is large and tends to grow. This is due to the fact that the creation of new progressive products, which are usually more expensive, does not exclude the possibility of using traditional cheap fasteners (bolts, screws, nuts, rivets, washers) in simple light-loaded units, guaranteeing 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 (in US terminology), totaling several billion dollars a year.
The classifier of state standards classifies fasteners for general machine-building applications into 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. Currently, many types of progressive fasteners that are not included in the Classifier of State Standards have been developed and mastered in various branches of the machine-building complex. The variety of fasteners based on structural, technological, functional and other characteristics makes it difficult to comprehensively classify and describe them. However, all fasteners can be divided into five groups. The basis of the classification is one most characteristic feature that determines the name of each group, namely: fasteners for mass use; high-strength threaded fasteners; fasteners for one-sided installation and impactless riveting; fasteners for high-life and hermetic connections; fasteners for joining polymer composite materials.
The convention of the proposed classification is that each group has a certain range of fasteners that can be classified into another group. For example, in the group of fasteners for single-sided installation and non-impact riveting, some designs of bolt rivets are intended for high-life connections or for connections of composite materials. At the same time, each of the groups includes fasteners of several classes according to the Classifier of State Standards. For example, the group of high-strength fasteners includes classes of bolts, screws, nuts, and the group of high-resource fasteners includes classes of bolts, rivets, etc.
However, the proposed classification allows designers and technologists to relatively easily understand the wide variety of fasteners and take into account specific features them in the design and development technological processes assembly of detachable and permanent connections, and will also provide assistance to specialists involved in the design and organization of specialized production of fasteners.
It is often very difficult to name a fastener correctly. What is this? Bolt or screw, anchor or dowel. Considering the wide variety of this class of products and the complexity of their correct name Let's turn to GOST, which regulates 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 a male thread at one end and a head at the other, forming a connection by means of a nut or threaded hole in one of the products being connected. |
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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 structural element to transmit torque to another. Note: The structural element of the screw for transmitting torque can 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 the wooden or plastic product being connected. Note: The special thread has a triangular, pointed profile and a larger cavity width compared to the width of the tooth. |
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A 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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A 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: The structural element of the nut for transmitting torque can be a polyhedron, knurling on the side surface, end and radial holes, splines, etc. |
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A fastener with a hole placed under a nut or the head of a bolt or screw to increase the bearing surface and (or) prevent them from self-unscrewing. |
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A fastener in the form of a semicircular wire rod, folded in half to form a head. |
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A fastener in the form of a smooth cylindrical rod with a head at one end, used 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 diameter of the smooth part of the rod exceeds the nominal diameter of the thread. |
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A bolt whose head is made in the form of a movable part of a hinge joint. |
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A bolt, the diameter of the smooth part of the rod is determined from the condition of ensuring the operation of the shear connection. |
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A bolt with a specially shaped head used to secure equipment to the foundation. Note: The special shape of the head can represent the spread tabs of the slotted part of the rod, the bent part of the rod, etc. |
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A screw whose diameter of the smooth part of the shaft is less than the internal diameter of the thread. |
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A screw that forms a special thread in a hole in one of the plastic or metal products being connected. |
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Self-tapping screw with drill shaped end. |
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A screw with a specially shaped end used to fix products relative to each other. Note: The special end shape can be cylindrical, conical, flat, etc. |
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Cylindrical pin with longitudinal groove along the length, made of spring steel. |
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Hexagonal nut with radially located slots for a cotter pin on the side of one of the end surfaces. |
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A hex nut, part of which is made in the form of a cylinder with radially located slots for a cotter pin. |
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Nut with spherical and flat end surfaces and a blind threaded hole. |
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A nut with flat protruding elements for transmitting torque. |
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Washer with a flat supporting 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 legs, toes, teeth, etc. |
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Rivet with a tubular cross-section rod. |
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A rivet, the end part of the rod of which has a tubular cross-section. |
Elements of fasteners
Kernel. Part of a fastener that directly fits into the holes of the connected products or is screwed into the material of one of them.
Fastener head. Part of a fastener having a shaft that serves to transmit torque and/or form a bearing surface.
Bolt head. The smooth portion of a bolt's shank, 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 supporting surface of a multifaceted nut, bolt or screw head, made in the shape of a cylinder or truncated cone with a diameter large diameter their circumscribed circle.
Support protrusion of a fastener. An annular projection on the bearing surface of a multi-faceted nut or bolt head, the diameter of which is less than the wrench size.
Note: The wrench size refers to the distance between the opposite edges of a multifaceted nut or bolt head, screw, measured in a plane normal to their axis.
Fastener slot. A specially shaped recess at the end of the head of a bolt, screw or screw, at the end of a set screw without a head, along a generatrix or at the end of a nut.
Note: The slot shape can be hexagonal, cross-shaped, through or non-through slot, etc.
Bolt spike. A protrusion on the supporting surface of the bolt head that serves to prevent it from turning.
Bolt lug. A protrusion on the supporting surface of the head and shank of a bolt, which serves to prevent it from turning.
Gimlet. The threaded, conical end of a screw used to cut threads into a piece of wood or plastic to form a joint.
GOST 27017-86 fully complies with the ISO 1891-79 standard 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 engineering use. Standards establish only basic terms. Today, when new types of fasteners appear in Russia, there is a process of formation of terminology; strictly speaking, this is a constant process. The desire of market participants to avoid discrepancies in names is quite natural.
The interstate standard GOST 27017-86 fully complies with the ISO 1891-79 standard 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 at 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 being connected. 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 motion of torque. Heads come with a spitz, with knurling, or simply 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 shape of a pointed, conical rod with an external special thread, and a head at the other end. The screw thread has a larger cavity 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 being connected by screwing.
Hairpin (Stud)- a fastener in the form of a rod or cylindrical rod with a cut external thread along the entire length of the product or only at the ends on both sides.
Pin- a special fastener in the shape of a cylindrical or conical rod. Designed for fixation various products during the assembly process.
Nut- a fastener with a metric threaded hole. For constructive transmission of torque, nuts can be multi-faceted, hexagonal, knurled on the side surfaces, with a slot, end and radial holes, etc. The design of the nut can be different: cap nut, extension nut (coupling), mustache, etc.
Washer- a type of fastener, a product with a hole placed under the head of a bolt, screw or nut to increase the supporting surface of the fastening structure and prevent self-unscrewing.
Split pin— a special fastener is in the form of a semicircular wire rod, folded in half at the bend to form a head.
Rivet (Rivet)- smooth fastener cylindrical in the form of a rod with a head, used to obtain a permanent connection, forming a head on the opposite end of the rod through plastic deformation.
Hardware- abbreviated phrase “metal products”. The concept of hardware unites a very wide range of various goods obtained and made from metal. Conventionally 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, spikes 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 various fastener elements are made, the strength and durability of the product as a whole depends.
In fact, such a concept as fasteners appeared long before our birth. For example, historians and archaeologists say that the first nail was not metal at all, but made from fish bone, sometimes from plant thorns, or simply carved from hard wood. By the way, the original construction fasteners were wooden and at the same time quite strong, as evidenced by the strength of the Kizhi structures that have survived to this day and still amaze tourists with their strength. Moreover, up to the 15th century inclusive, everything threaded connections were made piece by piece, 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 connection, became widespread along with the development of electrical metalworking.
The main types of construction fasteners and fasteners indispensable in the construction of buildings and carrying out repair work indoors.
Construction fasteners- direction of fasteners used in construction for connection building structures and various structures. This group includes the following 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 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 steel fasteners has a high degree of corrosion resistance and thus has an advantage over other types of fasteners. Corrosion resistance in unfavorable conditions for stainless steel fasteners is much higher, and it also has excellent resistance to oxidation in alkaline, acidic environments, and chloride solutions.
Thanks to long periods hardened fastener service of stainless steel, they are classified as high-strength fasteners. High strength fasteners one of the types of engineering fasteners, so called because it can withstand more significant loads and has a strength class of 8.8, 10.9, 12.9, and does not lose its strength characteristics at high temperatures.
Anchor- a fastener of the construction fastener category, there are varieties: anchor bolt and anchor nut. The anchor is able to stay inside foundations or a solid wall (strong, inelastic, non-fragile structure). Designed for fastening construction and other equipment as well as various structures. Anchors are usually used on all construction sites, from dams, nuclear power plants, up to and including a standard building.
Classical dowel used for fastening any parts in a solid, non-fragile and durable wall or ceiling panel. The principle of fastening the dowel is the expansion during installation from a screw or screw, which creates a holding friction force.
Clamp- another type of fastener. Clamps are mostly made to connect any types of pipes made of metal and plastic. Plastic clamps are used to fasten less durable materials than metal clamps, but they provide greater mobility of pipes.
Modern construction rigging makes it possible to choose fasteners for various types construction work. This type of rigging such as an eye nut and an eye bolt are used to organize the lifting and movement of loads during lifting and rigging operations. Steel rope or wire rope is used for lifting heavy loads in construction, these positions are important detail operating 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 for lifting and moving loads for various purposes and designs.
Each fastener is manufactured for a specific purpose, 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 plasterboard, 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, they really easily connect parts together. However, what is glued together cannot last happily ever after. Glue - has a chance to come off in one day, that's why it's glue! Nobody canceled fasteners or hardware!
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 on the farm can hardly be overestimated. The term "hardware" arose from the abbreviation of the phrase "metal products."
There are two types of fasteners: detachable and permanent. The fastener industry is constantly growing, and the variety of fasteners used is very wide. The reason is that these parts are an indispensable attribute of any development in the field of mechanical engineering. The standard for 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 there are.
Anchor
An anchor is a fastener designed to connect structures and products. 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 drive-in anchor with internal thread and a cone-shaped wedge is needed to secure materials and equipment to brick or concrete. Installing such an anchor is simple: 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 quick fastening in concrete, a common material for structures such as planks, 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 the concrete, into which the anchor is driven 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 are cylindrical metal fasteners with a metric external thread and a head at one end, usually designed for nuts. The bolt head can be hexagonal, cylinder or spherical. Bolts allow you to create a connection using a nut or a pre-made threaded hole in the part to be connected.
A stepped bolt differs in 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 attach equipment directly to the base.
The most widespread type is a bolt with a hexagon-shaped 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 friction force allows the connection to be secured. To transfer part of the load to the bolt, maximum precision in manufacturing the rod and the hole for it in the parts is required. To prevent parts from becoming deformed, washers are placed under the bolt head and nut. Bolt sizes allow you to find the right fastener for any task.
Nail
The material for making 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 can be either smooth or grooved. 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 greater 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 felt, wallpaper, and plaster nails are used. They are available with a flat head, wider than conventional nails, and a shorter shank. 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 driven in efficiently, you need to follow a number of requirements.
To prevent dents from appearing on the parts during nailing, you need to use a countersink. In order for the fastening to be strong, the nail shaft must enter 2/3 of the length into the lower part being fastened. When driving small nails, it is best to use auxiliary tools. To make the joints of the parts being connected stronger, it is better to drive the nail at an angle. When using thick nails, to avoid splitting the board, you need to slightly blunt their sharp ends. If you plan to hang any weight on a nail being driven into the wall, it should be driven not perpendicular to the wall, but at an angle from top to bottom.
A nail that has penetrated through must be carefully bent using a triangular file. In order not to damage the surface of the parts when pulling out nails using pliers, you need to use a plate that is placed under the pliers, reducing the pressure on the part. If you plan to dismantle parts in the future, 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 can provide sufficient fastener strength no worse than metal nails. One drop of nails of this type can withstand a force of 50 kg. But their main advantage is maintaining integrity decorative surface. Application area liquid nails very wide. They are used for gluing to a variety of wall and ceiling panels, plasterboard, chipboard, fiberboard, wood, cardboard, ceramics, stucco decorations, glass, metal and many other materials.
When purchasing liquid nails you need to be careful. Different brands of this material have a certain degree of adhesion.
It is advisable to use liquid nails:
- 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 be used to glue metal. They don't like either subzero temperatures. Nails on organic solvents have increased setting speed and can withstand temperatures down to -20°C. Their disadvantage is the presence of volatile harmful substances. Within 5 days after use they emit bad smell. Liquid nails set in 15 to 30 minutes, depending on the brand. However, they completely polymerize only after a day.
Screws
In order for screws to fully perform their function as reliable fasteners, 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 driven in like nails - they are screwed in completely. Before using screws small size First, a puncture is made using an awl. Large screws will be easier to screw if you first drill a hole of a slightly smaller diameter.
Screws are used to connect metal structures. The screw head helps to press the parts being connected, 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 internal hole of which allows the screw rod to pass through it. If the screw is rusty, a hammer or special crimps are used to remove it. Heating the nut can often help with this. gas burner or a blowtorch. If open fire is prohibited for some reason, you can use a hot iron rod or a large soldering iron.
screw
A nut is a type of fastener with a threaded hole cut inside. The most widely used are 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 shape of a cap;
- T-shaped, with a 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, and the parameters of the binder. The disadvantages of polymers include low heat resistance, tendency to deform under load, and aging.
Only screws correctly selected for the dowel can withstand the maximum load. They must have maximum permissible 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 self-tapping screws for fastening drywall sheets is not recommended.
A number of manufacturers produce 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 must be taken into account that the hole for installing the dowel must be drilled in accordance with the recommendations for depth, diameter and distance from the edge. There should be no cracks or chips as a result of drilling the hole. The hole must also be cleared of debris and dust.
Among the offerings of manufacturing companies, you can find varieties of dowels that have an increased length, necessary for soft and hollow materials. When installed in such a base, fastening can be achieved by fixing the internal stop of the parts. For installations occurring in hollow materials, fastening 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 interrelationships.
Rivet
A detail such as a blind rivet combined type, consists of an aluminum body and a rod made of galvanized steel. This design is the most common. The purpose of the rivet is to connect two or more surfaces of thin sheet. The need for a rivet arises in cases where a permanent connection using a power tool is required, when access on the side of the closing head of the rivet is limited or blocked.
There is also a 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 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. Fastening insulation, fiberboard, wooden parts produced by self-tapping screws with a large thread. Having a drill-shaped tip, it is capable of independently making holes in parts to be fastened. If a 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 plasterboard sheets to tin profiles. Universal self-tapping screw white 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 pressing surface of the parts to be fastened increases, which helps protect the joined surfaces from deformation when the nut is tightened.
Hairpin
A stud is a fastener that has the shape of a cylindrical rod with external threads cut either along its entire length or at the ends. This connection is used if none of the materials involved in the connection have threads. The connection is then secured with 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 are hardware and fasteners that are most widely used in construction and finishing work. They also cannot be replaced during installation. plasterboard sheets on a metal or wood frame.
Various types of screws are also used in roofing and facade work for connecting 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 easiest to use type of fastener. It has a very wide distribution and application.
3. Metric fasteners - 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 fastening parts to wooden bases.
6. Tapes perforated with holes - made from sheet steel (corners, punched tape...). Often used in the construction of wooden houses.
7. Rigging fasteners - used for fastening and moving various loads (cables, chains, carabiners...).
Anchor fasteners
There are several types of anchors:
- drive-in anchor - metal sleeve. One side is threaded, the other side is cut. There is a wedge inside, which, when driven (mainly into concrete), securely holds the structure being mounted;
- wedge - also used in concrete and natural stones. It is hammered in and additionally tightened with a wrench;
- expansion - a special expansion mechanism opens inside the base;
- chemical anchor - a pre-prepared hole is filled chemical composition and the fastening rod is inserted.
Electrical Installation Fasteners
Some types:
- dowel-bracket for round and flat wires;
- cable tie;
- universal wire clamp;
- fastening flat and round wires;
- 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 joining wooden parts;
- for connecting metal parts;
- roofing
Protection of fasteners by galvanic coating
Serves to increase service life. Anti-corrosion coating can be:
- copper;
- tin;
- zinc;
- nickel;
- cadmium
Almost a person’s entire life is permeated with connections: social, family, moral, business. Even everything that surrounds a person is created thanks to strong connections. These connections are held in place by fasteners. IN modern home Countless such elements are used in construction.
Why do you need fasteners?
Fasteners are designed to connect and hold connected various parts 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 wide variety of types of elements: nails, nuts, bolts in St. Petersburg and much more.
Variety of fasteners
There are thousands and thousands of types of fasteners, taking into account 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 securing 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 prefer brands such as ABC, Fisher, Bralo (Spain), Sormat (Finland), Wurth (Germany), Omax (USA). It's more expensive types products of high quality. Most of the offered assortment is made in China, Thailand or Taiwan. This fastener is more affordable and is quite suitable for minor home repairs. But it is unlikely to be suitable for serious work.
Nails
Probably everyone knows what nails are. They have firmly entered human life and occupied an important place in it. Nails are divided into:
- Construction ones with a flat corrugated or smooth head;
- Special (“crutches”, “doublet”);
- Slate nails;
- Corrugated, screw or ring nails for fixing roofing.
Screws, screws, screws
All of these types of fasteners look like threaded rods with a head. Their scope of application is finishing, façade and roofing, installation, assembly of furniture. The difference between screws, screws, and self-tapping screws is that in order to use a screw, you must drill and tap a hole. There is no need to do this when working with a screw. 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. Practical and most convenient fasteners have been created for almost every type of work.
