Special fasteners. Types and work. Application and features. Fasteners Fasteners for balcony structures

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- fastener with metric external thread shaped like 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.

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 fixing 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 grid, spring washers, adjustable 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 they are made various elements fasteners, 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, until the 15th century inclusive, all threaded connections were 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 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 on premises.

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, and 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 is much higher for stainless fasteners, and it also has excellent resistance to oxidation in alkaline, acidic environments, and chloride solutions.

Thanks to the long service life of hardened fasteners 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, before standard building inclusive.

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 used for fastening less durable material than metal clamps, however, they provide greater pipe mobility.

Modern construction rigging makes it possible to select fasteners for various types of 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 cable is used for lifting heavy loads in construction; these positions are an important part of the operating lifting mechanism, both for manual hoists and for cranes. A chain is also one of the types of rigging. Steel chains are used in various lifting mechanisms, from manual to cranes. Steel chains, like steel ropes, are used to lift and move loads for various purposes and structures.

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!

For use various connections Wood in the field of construction cannot be done not only without tools, but also without relevant experience. That is why inexperienced craftsmen do not always make such connections accurately. One of best options— professionals use various types of fasteners for the array, which are made of metal.

Many surviving architectural monuments made of wood were built without nails, using only an ax. This fact causes true pleasure to this day. However, centuries later, the fasteners made of metal, used to build solid wood buildings, have changed radically, and it is for this reason that today it makes no sense to repeat the experience of our ancestors.

It is preferable to build quickly and without complications. Let's talk in more detail about the fasteners offered by manufacturers, taking as an example parts that make it possible to simplify the connection of beams with floor joists, or wall surfaces made of solid wood.

Perforated fasteners

When beams and also joists floor surface hidden in the interior space, they can be connected using beam shoes. This fastener for wood structures is suitable for fastening solid wood not just to wood, but also to concrete and brickwork. It is created from durable steel.

Manufacturers advise fastening such fasteners to the parts being connected with special screws, and in case of excessive load, or fixing to a stone material, use the holes for the necessary bolts. In addition to anchor shoes, today you can purchase special clamps and much more.

Tenon and groove

This galvanized wood fastener consists of a tongue and groove section that fit together to provide better transfer of horizontal as well as vertical forces.

The connection can be visible or hidden; for these purposes, the steel parts are recessed into special grooves in advance.

Three-dimensional slats

The modern Italian company produces fastening elements that are placed perpendicularly and vertically at an angle, using T-shaped slats created by extrusion from a high-strength steel alloy. They are produced in several modifications designed for different levels of loads.

The fastening system must be selected according to the size range of sections of the combined beams and the dynamic as well as static loads acting on them.

During the installation process, the slatted base is attached to the beam using self-tapping screws. Then a groove of the same size as the slatted shelf is created on the end part, attached to the base of the joist beam. If there is no perforation, the shelf is equipped with a log and the connection is secured using self-tapping screws.

Hidden details Hedgehog

These connectors are steel washers, the base of which is equipped with holes drilled under the slope. These holes are for self-tapping screws. In the center of the washer there is a threaded hole into which a pin is inserted. Its free end is threaded into a special hole and secured with reverse side beams as a part with an enclosed washer.

The created connection functions perfectly not only in pull-out, but also in shear. If there is excessive load in the area of ​​the end part of the joist, it is possible to install several elements at the same time.

Fasteners with complex threads

Unusual self-tapping screws that make it possible to save time, cash, since this option does not require metal parts. Self-tapping screws are equipped with threads, which help create a high degree of resistance when pulled out, and are also tightly screwed into an array, which completely changes their traditional functioning.

In this case, the work of the screws occurs exclusively by pulling out, which gives them the opportunity to absorb most of the forces that fall on the connection. So, you can fasten elements at an angle, combine parts, minimizing their deflection, as in the photo of wood fasteners below.

Special purpose self-tapping screws

Using similar elements, quite massive wooden crafts. The head has milled ribs and is easily recessed into the product, while the tip is created like a drill. In the middle of the screw, the cutter makes a larger hole, helping to tighten the element as tightly as possible.

Self-tapping screw adjustable type will be useful for fastening door frames, window openings, solid wood lathing to wood, metal. The self-tapping screw is screwed directly into the box, as well as the wall surface or power part located behind it.

The self-tapping screw acts as a weather vane for high-quality fastening of solid wood cladding to a base made of steel. It has a tip in the form of a drill and wings placed above it to expand the hole in the tree.

When drilling metal products, the wings break. As a result, having made a thread in a metal part, the self-tapping screw fits tightly to it, while the solid element is attracted by its head to the metal.

Photos of wooden fasteners

Without reliable fasteners, it is impossible to build a house or renovate an apartment yourself, or with help. You won't be able to attach a rafter to a beam, you won't be able to hang a shelf, you'll never be able to assemble furniture. Here is an incomplete list of what you cannot do without having a nail, screw, self-tapping screw or bolt at hand. Many will say, what will this article be about if you just listed all the popular fasteners. In principle, all that remains is to add anchors, rivets, dowels, confirmations and screws. That's all, in fact, these are just names of hardware, and fasteners have a slightly different classification.

Most likely, this concept was invented artificially in order to combine all the details that can be used to connect various building elements and.

This group of fasteners includes screws, self-tapping screws, nails, dowels, etc. There are also types of construction fasteners, namely dowels, anchors, metric products and self-tapping screws.

Stainless steel fasteners stand out as a separate group. As a rule, it is manufactured according to the DIN standard (Germany). Such fasteners have an almost unlimited service life, since they are not exposed to precipitation and are quite resistant to chemical reagents. Moreover, the aesthetic appearance of this fastener will not be spoiled.

If there is a need to securely fasten something, then anchors will come to the rescue. An anchor is a special type of fastener consisting of two parts, a pin or core and a sleeve. The use of anchor fasteners is not regulated, but, as a rule, builders use anchors for greater reliability of fastening. So, if you need to secure a heavy element to a hollow base or concrete, then an anchor is perhaps the only way to do this. You can often see the use of anchors when installing PVC windows. Depending on the problem that needs to be solved with the help of an anchor, the necessary or most suitable anchor is selected - a frame anchor, an anchor with a hook, a driven anchor, an anchor with a ring and an anchor bolt.

There are also dowels that have the same purpose as an anchor, but are used for lighter loads.

Chemical anchors stand in a separate group - these are devices that are structurally different from the classic anchor. A chemical anchor is more of a method of attaching a pin to a base. As a rule, such anchors are used for maximum loads that conventional anchors cannot withstand. To secure the anchor, a hole of the required diameter and depth is made. The dimensions of the holes are strictly regulated by the manufacturer of the chemical anchor. Then, using a special gun, a certain amount of chemical glue is placed into the hole, then the anchor itself is inserted into the hole filled with glue. As a result chemical reaction glue with the base and body of the anchor, mutual penetration of one into the other occurs. The end result is a permanent connection that can withstand enormous shear, torsion and bending loads.

High strength fasteners

By by and large anchor fasteners can be classified in this group. However, it all depends on the grade of steel used and production technology. Required mechanical properties high-strength fasteners class 8.8. 10.9 and 12.9 is achieved by sequential heat treatment, a combination of heating and cooling (quenching and tempering). Also, high-strength fasteners have greater resistance to precipitation and chemical attack compared to conventional ones.

Inch fasteners

IN English speaking countries– Great Britain, Australia, USA widely use inch fasteners with threads of various pitches (large – UNC and small UNF). The only difference between this fastener and the metric one is that the unit of measurement is inch, not mm. Those. We receive fasteners that meet the standards of the countries listed above.

Almost all of its types listed above can be safely classified as furniture fasteners. There are also nails, bolts, and screws. Only screeds are specifically used. This compound is not used anywhere else except in furniture production.

Welded fasteners

This type of fastener is used for various technologies welding Structurally, nails, bolts, bushings, and threaded rods are used for welding.

Brass fasteners

The main advantage of this fastener is its low cost compared to stainless steel fasteners. At the same time, the products withstand the aggressive influence of the external environment much better. In addition, like stainless steel fasteners, brass has the same decorative qualities. It is also worth noting the absence of magnetization, as a result, the absence of interference when used in electronic devices.

A special group stands out for rigging fasteners. This is a fastener that is used for rigging and lifting operations. These are staples, thimbles, lanyards, belts.

Requirements for construction fasteners.

1. Securely fasten structures.

2. Have a convenient and easy way to use.

3. Fasteners must be maximally protected from aggressive environmental influences and have excellent decorative properties where required.

Types of metric fasteners used in construction and repair
Vibrating slats: types and purpose

Fixed connections widely used in mechanical engineering are divided into two types: detachable (made mainly using threaded fasteners- bolts, screws, studs and nuts) and one-piece (performed various types 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 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 of the most characteristic feature, which determined 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 their specific features when designing and developing technological processes assemblies of detachable and permanent connections, and will also provide assistance to specialists involved in the design and organization of specialized production 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.

	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.
	A fastener for forming a connection or fixation, made in the form of a rod with an external thread at one end and a structural element for transmitting torque at the other. 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.
	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.
	A fastener in the form of a cylindrical rod with external threads at both ends or along the entire length of the rod.
	A fastener in the form of a cylindrical or conical rod for fixing products during assembly.
	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.
	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.
	A fastener in the form of a semicircular wire rod, folded in half to form a head.
	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.
	A bolt whose diameter of the smooth part of the rod exceeds the nominal diameter of the thread.
	A bolt whose head is made in the form of a movable part of a hinge joint.
	A bolt, the diameter of the smooth part of the rod is determined from the condition of ensuring the operation of the shear connection.
	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.
	A screw whose diameter of the smooth part of the shaft is less than the internal diameter of the thread.
	A screw that forms a special thread in a hole in one of the plastic or metal products being connected.
	Self-tapping screw with drill shaped end.
	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.
	A cylindrical pin with a longitudinal groove along its length, made of spring steel.
	Hexagonal nut with radially located slots for a cotter pin on the side of one of the end surfaces.
	A hex nut, part of which is made in the form of a cylinder with radially located slots for a cotter pin.
	Nut with spherical and flat end surfaces and a blind threaded hole.
	A nut with flat protruding elements for transmitting torque.
	Washer with a flat supporting surface.
	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.
	A washer used to prevent self-unscrewing of fasteners using structural elements. Note: Structural elements washers are tabs, toes, teeth, etc.
	Rivet with a tubular cross-section rod.
	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 part of the bolt shank is cylindrical, oval or square shape, directly adjacent to the head and serves to center the bolt or prevent it from turning.

Fastener collar. A protrusion on the supporting surface of a multi-faceted nut, bolt or screw head, made in the shape of a cylinder or truncated cone diameter greater than the diameter of their circumscribed circle.

Support protrusion of a fastener. An annular projection on the bearing surface of a polygonal nut or bolt head, the diameter of which smaller size Full construction.

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.

When performing a wide range of repair and construction work, it is impossible to do without the use of various fasteners. On modern construction market presented a wide range of of these products, which are necessary for high-quality solutions to various technical and technological problems. Their functional purpose can be completely different - starting from fixing the board with a simple nail, and ending with the installation of the anchor, which must withstand increased operating loads.

This material will discuss the main types of fasteners, various classifications, GOSTs, markings and areas of their application. They come in a wide variety of shapes, sizes and purposes - the most common today are:

• nuts;
• dowels;
• anchors;
• screws;
• self-tapping screws;
• rivets;
• hairpins;
• washers and others.

Depending on the thread pitch, fasteners are metric or non-metric (adapted).

In addition, there is another classification of fasteners - it is based on other criteria. According to it, these elements are:

• threaded, increased strength;
• fasteners mass use;
• fasteners for shockless fixation and one-sided installation;
• elements for hermetic structures;
• fasteners necessary for fastening polymer composite materials.

This classification, although it significantly simplifies the sorting process, is conditional, since elements of one group may also belong to another. Let's take a closer look at the main ones.

Nails

Perhaps today there is no master who would not use nails in the process of his work. This is the most ancient and widespread today fastening material, which is widely used in many industries economic activity person. The material of their production is usually steel or steel types wire. The nail marking consists of two numbers:

• rod diameter;
• its length (in mm).

The heads of these elements can be either smooth or corrugated, and screw and club nails can have helical, longitudinal and transverse grooves, burrs or dents on the shaft. Such products provide significant resistance to pull-out processes.

Depending on the technical characteristics of the material, the scope of use of nails also differs. For example, hardened steel products can be safely driven into brick or concrete walls. However, when working with them, you should pay attention to their high fragility of this material. In order to attach them to hard surfaces, it is necessary to use wallpaper, tar paper and plaster varieties nails They are produced with flatter and wider caps than usual, as well as shorter stems. In aggressive environments, copper nails, which are practically not subject to corrosion processes, as well as galvanized nails or alloy steel products can be used.

As for the technological features of driving nails, they also have their own specifics. These processes require taking into account certain nuances, so we recommend using our professional advice:

• to prevent the occurrence of dents while driving nails, it is necessary to use a countersink;
• to ensure fixation strength, the fastening rod must be at least 2/3 of the length included in the lower fixed part;
• when driving small nails, it is best to use special auxiliary accessories;
• To increase the strength of joints, nails should be driven in at an angle rather than straight. The same applies if you need to hang something on it;
• if the nail went through the wall when driving, it should be carefully bent and polished using a triangular file;
• to prevent damage to surfaces when pulled out with pliers, you simply need to place a plate under them that reduces the pressure;
• if in the future it is planned to dismantle parts, then better than nails do not use at all, preferring screws.

Very often, liquid nails can be used during the work process. They are made of polymer materials and rubber and are able to provide adequate fastener strength indicators no worse than traditional nails. One drop of such a substance can withstand up to 50 kg of load, but their main advantage is the complete preservation of the integrity of decorative surfaces.

Scope of use liquid nails very wide. They are used for fixing various panels, drywall, chipboard, fiberboard, plywood, cardboard, ceramics, stone, stucco, glass and much more. However, when choosing these fasteners, it is necessary to pay special attention to adhesion indicators, since different types materials have varying degrees. They are most appropriate to use when:

• temperature not lower than -90 С;
• high room humidity.

For example, some types of neutral nails are harmless because they are based on water, but they are not suitable for gluing metal. Liquid nails based on organic solvents are different high speed adhesion and can withstand impact temperature regime up to -25 С. Their only disadvantage is the presence of harmful volatile components that emit unpleasant odors for 5 days.

The setting of such nails occurs within 10-40 minutes, depending on the type and marking, but complete polymerization occurs only after 24 hours.

Self-tapping screws

Self-tapping screws also occupy a special niche among fasteners. Their varieties are on modern market not so much - full classification is possible only according to 3 main criteria - the material into which they are screwed, size and functional purpose. According to the first criterion, the following types of self-tapping screws are distinguished:

• for metal;
• for wood.

Both products can have different lengths, widths, diameters, as well as different steps thread. Typically, self-tapping screws for metal surfaces have a fine thread pitch, unlike “wooden” ones, which have a larger thread pitch.

Products for metal can be of several types - self-tapping and those that require preliminary drilling of the metal. The first type has a special drill at the tip, the size of which indicates the thickness of the metal into which it needs to be screwed. An example of such self-tapping screws are tex, which are used to fix gypsum plasterboard profiles. As for their second subgroup, it includes black self-tapping screws, which are necessary for attaching gypsum boards to the metal profile.

In addition, the classification of self-tapping screws can also be carried out according to their functional purpose. For example, there are self-tapping screws for roofing and general purpose. Roofing ones have a wide cap with a press washer, which is necessary to seal the hole to prevent water leakage.

Anchors: types and features of application

The anchor is fastener, which is designed for fixing various structures and materials. In addition, this name characterizes parts partially concreted into any concrete product. Depending on the design, shape and purpose, the following types of anchors are distinguished:

• ceiling;
• driving;
• wedge;
• frame;
• anchors with half rings and rings;
• anchors with nuts.

What unites them general function- fastening. For example, drive-in anchors with internal type threads and a cone-shaped wedge are necessary in order to fix various products and materials to a brick or concrete base. It is installed quite simply: it is fixed into a pre-made hole. Its radius and depth are selected depending on the size of the anchors themselves.

Wedge-shaped products are used for rapid fastening of planks, profiles, suspended ceilings. These types of anchors are very often used for fixation heavy equipment on a solid base. For high-quality installation wedge anchors, a hole is drilled in the concrete base into which the product is hammered using a hammer, which is subsequently tightened with nuts. As for ceiling anchors, they can be made of galvanized steel, and are necessary for fixing metal profiles, facades, railings, gratings and other products on a concrete or stone base without cracks. Frame anchors are necessary for attaching frames and wooden door frames to concrete walls.

A lot of users try to use this type of fastener for other purposes. For example, they are attached to brick walls, as a result of which the fastening element and nerves deteriorate. But the main thing is the very large holes that remain in the brick after the anchor is removed. They are used, as a rule, in concrete materials, while in soft materials such bolts tend to simply turn. Classification of anchors is also a very difficult task, since products can belong to different groups at the same time, but usually there are three types:

• fastening;
• hook-shaped;
• loopback

The first type is universal, the second is designed for hanging objects, and the third is for catching something. In addition, these fasteners can be divided into the following main groups - with a wedge at the end and with a wedge in the form of a nut. Anchors are manufactured in fixed sizes - the smallest have a length of 50 mm and a diameter of 6-8 mm, the largest - up to 500 mm and a diameter of up to 22 mm.

Tip: the question of how to install an anchor can be solved very simply. To do this, you simply need to select the correct diameter of the hole - you need to drill with a drill of exactly the same size as the anchor itself - you can’t expect that a 12 mm bolt will hold in a 15 mm hole. It is also not advisable to wrap anything around the anchor, it does not make any sense - just insert it into the hole and tighten it with a screwdriver.

Dowels

These fasteners are also extremely popular in the modern construction market. They are necessary for high-quality fastening various items and materials for solid structures. There are three types of dowels:

• metal ones are the most ancient. They can be used on almost all surfaces, but it is problematic to hammer them in with a simple hammer, especially in hard materials– therefore, pneumatic, electric or cartridge pistols are more often used. Such dowels differ from each other only in diameter and length;
• installation ones are the most common today. They can be manufactured in two variations, which differ from each other in the shape of the plastic tip. In some cases they are mounted in a specially prepared chamber, but in others they are not (the plug has a mushroom-shaped shape). Such dowels are installed using a hammer drill - a hole is made, and then a plastic plug is inserted into it, into which a steel nail is driven or screwed. If necessary, you can then very easily unscrew it thanks to the special thread. Depending on the diameter, dowels are 6.8 - 14 mm, and lengths - 30-300 mm;
• spacer (Bierbach dowel) - made of steel and demonstrate high performance characteristics for use in concrete foundations. They consist of two wedges that are connected to each other in a movable way using a washer. Pre-mounted drilled holes, in which they are then wedged with one impact force of a hammer.

They are usually used for fastening in solid wall structures. The fixation of the dowel is based on the frictional force that occurs due to the spacer of the fastener during installation with the appearance of a holding force. The dowel can withstand increased loads static in nature - when installing it, the fasteners are destroyed during the pulling process.

The product itself is made of polymer materials. Their physical and mechanical characteristics capable of greatly transforming, depending on various influences and conditions. These include, first of all, the parameters of the filler, the ratio of the components of the polymer material, and the properties of the binder. The disadvantages of polymer dowels include low heat resistance, a tendency to deform under load, and increased aging. Only screws can withstand maximum loads if they are correctly selected for the dowel. They must have all parameters (length and diameter) that fully correspond to the parameters of the dowels. The use of other fasteners extends increased requirements to the thread profile, since it is they that determine the spacer effect. It is undesirable to use self-tapping screws and self-tapping screws to secure drywall.

Drywall fastening: molly

For high-quality fixation of gypsum board sheets, there is only one group of fasteners, which is called “molly”, received from the company that developed this fastener. It consists of two parts - an empty folding tube with special slots, a nut and a screw. As the screw is tightened, the tube is assembled and crimped on both sides of the gypsum board. There are two types of molly:

• metal;
• plastic.

The first type is the most reliable - it is installed using special pliers, and to install plastic ones, you need to pre-drill holes with a diameter of 8 mm, insert fasteners into them, and then tighten the screws. Using such elements, only light objects can be hung on drywall - if it is necessary to fix heavy ones, then embedded profiles should be provided.

Bolts

Bolts are cylindrical fasteners that have a metric cylindrical external thread and a head that is designed to fit a nut. They make it possible to create connections using nuts or pre-made threaded holes in fixed parts. They are in form:

• stepped, in which the thread diameter is smaller than the diameter of the smooth part;
• foundation ones, which have a specially shaped head that helps secure equipment and units to the base;
• with a hexagon-shaped head for a wrench - this is the most common design option.

A bolt is inserted into a pre-prepared hole in the parts that need to be fastened, after which a nut is screwed onto the thread and the elements are tightened using wrench. The connection is fixed due to friction - but in order to transfer part of the loads to the bolt, it is necessary to ensure maximum precision in the production of the rod and the holes for it. To prevent deformation of parts, washers are installed under the bolt head and nuts. Bolts are always used in combination with nuts.

Nuts: types and principle of operation

Nuts are also a very popular type of fastener, which is distinguished by specially cut holes inside threaded connection. Galvanized products are the most widely used, and their shape can be completely different - hexagonal, round with notches, square, with protrusions for gripping with fingers. Main functional purpose Nuts are the connection of parts using bolts. They are:

• hexagonal;
• square;
• in the shape of a “lamb”;
• flanged with grooves for a cotter pin in the form of a cap;
• T-shaped, with special plastic inserts.

In addition, nuts are also divided into strength categories according to the types of bolts with which they are used.

Rivets

Combination type blind rivets consist of an aluminum body and a rod, which is made of galvanized steel. Such design feature is one of the most common and in demand today. Rivets are used to join two or more surfaces of thin sheets– with their help a permanent connection is created. Also on the modern market there are rivet nuts. These are fasteners widely used in electronics and mechanical engineering. They are necessary to create a threaded connection in metal materials or other thin surfaces with high strength.

Among the large selection of these fastening products, one of the most durable are threaded steel rivets. They are protected from corrosion by galvanizing. In design, such products differ from simple exhaust systems in that they can not only connect sheets of materials to each other, but also have an internal screw thread. They are mounted in hard to reach places, where it is impossible to reach with a riveter. There is a wide selection of standard sizes on the modern market, so choosing them to solve the required technical problem is not difficult.

Use of screws, screws and other fasteners

In order for the screws to correctly perform the functions assigned to them, their sizes should be selected correctly. Screws are fasteners that are necessary for wood structures - their shaft tapers towards the end and acts as a drill. This type of fastener cannot be used as nails, driven into the surface - they must be completely twisted from start to finish. Before using small screws, you should make a preliminary puncture, and large ones, a hole of a smaller diameter.

Screws are used to secure metal structures. Their heads allow high-quality pressing of the part to be joined, and the shape is selected in such a way as to make the process as easy as possible using a wrench or screwdriver. Depending on this, the screw heads can have different shapes:

• hexagonal;
• semicircular;
• secret.

They are always screwed into threaded holes, and in some cases they may have a design in which a hole is drilled at the end of the screw for cotter pins - wire rods with a semicircular cross-section. It is necessary in order to prevent spontaneous unscrewing of the fastening element.

If the screw is rusty, a hammer or special crimps can be used to remove it. Often help in this process can heat the nut using gas burner or blowtorch. If the use of open fire is prohibited for some reason, then a red-hot iron rod or soldering iron can be used.

Other products are also used for high-quality fasteners:

• washers are round plates made from cold rolled strip. They are used to increase strength bolted connections by placing it under the head of a bolt or under a nut;
• studs are cylindrical rods with external threads cut along the entire length or at the ends. Used in cases where more than one material in the connection does not have a thread;
• screws are rod fasteners with a conical point that have the property of creating new threads in plastic or wooden products.

On the market building materials there is very big choice fasteners. They must be selected in full accordance with the technological features of the application and technical goals, as well as operating conditions.