Nail plate application. Metal toothed (nail) plates - MZP: for the manufacture of wooden roof trusses

It is a metal plate, on the surface of which there are several rows of spikes made by stamping.

It is they that, when installing this fastening element, “bite” into the wood and are firmly fixed in it.
Depending on the variety and size, nail plates can have from 2 to 16 rows of spikes, the height of which is usually about 8-14 millimeters.

The fastening element is made of galvanized steel with a thickness of 1 to 1.5 mm by cold stamping, the teeth have a height of up to 14 mm.

What are gear plates made of?

Serial production of nail (toothed) plates is carried out at a specialized industrial equipment. They are made from galvanized sheet steel.

In the production of this type of fastener, powerful hydraulic presses are actively used, characterized by high productivity.

This equipment allows you to produce high-quality and, importantly, relatively inexpensive nail plates in large quantities.

Scope of application of nail plates with GP marking

Metal serrated nail plates are also used as connectors for construction.

They are great for firmly connecting elements together wooden rafters, used in the construction of buildings with large spans.

Fastening plates (toothed) are also used to connect timber, and it turns out to be very strong and durable. This fastener greatly simplifies and speeds up the assembly of lattice frames.

Advantages of tenon mounting plates

Tenon fasteners have gained wide popularity due to the numerous advantages and benefits that their use offers.

The main one is, perhaps, that this fastener guarantees a strong and durable connection wooden parts. In this case, the wood does not split and its integrity is maintained.

Thanks to the presence of a high-quality anti-corrosion coating, the nail plates are virtually rust-free, which is especially important for such a hygroscopic material as wood.

Construction frame houses, V Lately, is gaining more and more momentum. This is due to the fact that frame housing construction, in the most short time can make your dream come true by giving you your own, country, warm, natural and environmentally friendly clean house. In addition, we note that frame houses are relatively inexpensive, because their construction implies savings on the foundation, as well as the use of labor.

The strength of such structures is undeniable. The fact is that thanks to innovation, new types of fastening elements have recently begun to be actively used, one of which is the nail plate. Actually, we will talk about what exactly this fastener is in this article.

Nail plate, application features

Such fasteners are supplied to the market building materials in the form of a plate, which is made of alloy or galvanized steel. The latter allows the plate not to oxidize or rust, performing its functions for a fairly long period of time. This plate is called a nail plate because nails (spikes) obtained during stamping protrude perpendicular to its plane. Average length one spike is equal to 8 to 9 mm. Depending on the purpose, one plate with nails may have different number strips with teeth.

The plate itself is very thin, which allows it to be used at almost any stage of house construction. However, the main area of ​​application of the plate is the construction of a rafter system. In this case, the dimensions of the fasteners are selected based on the dimensions of one rafter. As a result, a plane, say, 50 mm wide and 110 mm long, allows you to fasten rafters located in the same plane without using additional fasteners, including nails and screws.

One of the main problems that a potential consumer may encounter when using the plate is natural humidity tree. As you know, wood dries out during use, changing its shape, weight and volume. In this regard, when using a plate with nails, for example, when building a log house, you should not skimp on the foundation, so that the effect of changing the geometry of the building does not increase due to the subsidence of the house under its weight. Only in this case, nail fasteners can fully reveal all their useful properties:

• Powerful and durable connection. It has been scientifically proven that today no fastener can compete with a nail plate. At the same time, it does not damage the integrity of the tree, does not lead to rotting, and does not cause cracks and chips.
• Complete absence of swaying of the rafters, even in strong gusty winds. In this case (of course, if implemented smooth cut) The “monolithic” base of this fastener ensures the tightest connection.
• No shrinkage. Even if your house is not built well enough and during its operation it shrinks, rest assured that the geometry of the rafter system will not cause curvature, which will not lead to a change in its shape.
• Doesn't rust. Some models of plates are additionally coated with galvanic coating. But even without it, rust will be completely absent.
• The installation process of such fasteners does not require the use of electrical priors. In addition, when compared with conventional nails and self-tapping screws, it must be said that installation of a nail strip is much faster.
• Low cost. Buy a nail plate for construction own home everyone can. In general, it is sold in any city in our country, but in Moscow, it can be purchased at the address: Moscow region, Balashikha, st. Sovetskaya, 35.
• Excellent compatibility with any tree species. There are cases that metal dowels are simply rejected by the tree, as a result of which the wood begins to rot and will soon require replacement. In the case of a nail plate, this is guaranteed not to happen during the entire life of your frame house.

Such wooden structures are most relevant for the construction of garages, garden buildings and summer cottages.

Given technical manual describes the principles of connecting parts, provides illustrations of the main structural units and recommendations for choosing sections of wooden hanging elements rafter systems.

More complex types wooden structures must be calculated and assembled at the manufacturer's factory.

Rice. 11.01 Installation of homemade wooden hanging rafter systems. The joints of the lower chord should rest on load-bearing walls in the middle of the span.

1. The upper and lower chords of the structures are in the same plane.
2. Steel perforated plates are located on both sides.
3. The lower belt of the structure is attached to the upper one with an overlay.
4. Wooden overlays may only be nailed on one side.
5. A bolted connection using lock washers with external teeth, clamped between the parts to be joined, and also using washers.

Rice. 11.02 Span, roof angle, location load-bearing wall

1. The lower chord of homemade wooden triangular three-hinged arches (hanging rafter systems), designed for a span of more than 4.2 m, must rest in the middle on a load-bearing wall.

Rice. 11.03 Example of a perforated steel plate with an arrangement of holes guaranteeing optimal distance between the nails

Table 11.1

Selection of the cross-section of elements of wooden triangular three-hinged arches, required amount nails for connections on perforated steel plates. Selecting the diameter of lock washers for bolted connections

Snow load S 0, kN/m²	Roof angle 18°≤ α ≤ 22°					Roof angle 22°≤ α ≤ 37°				Roof angle 37° ≤ α ≤ 45°
	Span L*, m	Upper chord h, mm	Bottom chord h, mm			Upper chord h, mm	Bottom chord h, mm	Connection of the upper and lower chords, junction of parts of the lower chord*****		Upper chord h, mm	Bottom chord h, mm	Connection of the upper and lower chords, junction of parts of the lower chord*****
				Number of nails****	D st. washers ***, mm			Number of nails****	D st. washers ***, mm			Number of nails****	D st. washers ***, mm
2,5	3,0	123	173	6	50	123	173	5	50	123	173	3	50
	3,6	148	198	7	62	148	198	6	50	148	198	4	50
	4,2	173	223	8	-	173	223	7	62	173	223	4	50
	4,8	198	148	9	-	198	148	8	-	198	148	5	62
	5.4	198	148	10	-	198	148	8	-	198	148	5	62
	6.0	223	173	11	-	223	173	9	-	223	173	5	62
	6,6	223	173	12	-	223	173	10	-	-	-	-	-
4,5	3,0	123	173	8	-	123	173	7	62	123	173	4	50
	3,6	173	198	10	-	148	198	9	-	148	198	5	62
	4,2	198	223	11	-	173	223	10	-	173	223	6	62
	4,8	223	148	13	-	223	148	11	-	223	148	7	-
	5,4	223	148	14	-	223	148	12	-	223	148	7	-
6,5	3,0	148	173	11	-	148	173	9	-	148	173	5	62
	3,6	173	198	13	-	173	198	11	-	173	198	6	-
	4,2	223	223	15	-	198	223	13	-	198	223	7	-
* The thickness of the structure's chords is 48 mm, the grade of lumber is 3rd, the center distance between the arches is 600 mm. ** For a span of more than 4.2 m, the lower chord of the arch must rest in the middle on the load-bearing wall. *** Also used are bolts with a diameter of 20 mm and washers 60x60x5 mm. **** Design load for 1 nail 646 kN. This number of nails should be used on each side of the joint, on both sides of the structure. ***** The joint of the lower chord of the arch should be located above load-bearing wall in the middle of the span.

Rice. 11.04 Basic parameters of homemade wooden tangular arches

1. The top chord of a homemade wooden triangular arch.
2. Bottom belt.
3. Flight.
4. Overhang.
5. Roof angle.
6. The load-bearing wall strapping should extend all the way to the outer edge of the junction of the upper and lower chords of the truss.
7. The roof overhang should not exceed 500 mm.

Rice. 11.05 Connecting the upper and lower chords of the structure using perforated steel plates and nails

1. For homemade wooden arches, in this case, plates are used on both sides:
   100×240×1.5 mm, if the span is up to 4.2 m
   100×300×1.5 mm, if the span is more than 4.2 m
   In this case, the calculated snow load should be less than 4.5 kN/sq.m
2. Minimum distance from end wooden element should be more than 60mm.
3. In this case, you need to use 4.0x40 mm corrugated nails, distributing them evenly over the plate, observing the minimum indentations (items 3 and 4). The number of nails per connection is selected according to table 11.1.

Table 11.2

Rice. 11.06 Connecting the upper and lower chords of the arches using a bolt and two one-sided lock washers with external teeth, clamped between the parts to be connected, as well as using washers

1. Lock washers with external teeth - 2 pcs. The diameter of the lock washers is selected according to table 11.1.
2. Bolt, 20 mm. Minimum distances from the end and edges of wooden elements, see table 11.2.
3. Washer, 60×60×5 mm.

Rice. 11.07 Connecting the upper chords of triangular arches in the ridge using perforated steel plates and nails

1. Perforated steel plates 80×140×1.5 mm are used on both sides.
2. On each side, along the outer edge of the plate, 2 corrugated nails 4.0x40 mm are driven in.
3. The area of ​​the plate that can be used for driving nails.
4. The minimum distance from the end of the wooden element must be greater than 40mm.
5. The minimum distance from the edge of the wooden element must be greater than 28mm.

Rice. 11.08 Connecting the upper chords of the arches in the ridge using overlays made of boards or plywood

1. Overlay 148×300 mm made of boards more than 30 mm thick or plywood more than 15 mm thick.
2. The area of ​​the plate that can be used for driving nails.
3. Nails 3.5×90 mm, 8 pcs. from each side.

Rice. 11.09 The joint of the lower chord of a homemade wooden triangular arch should always be located above the support. If there is no support, then gaps in the lower chord are unacceptable, and the maximum length of the lower chord should be less than 4.2 m Rice. 11.10 Connecting the elements of the lower chord of the arch using perforated steel plates and nails

1. Steel perforated plates 100x300x1.5 mm are mounted on each side and centered relative to the joint.
2. The area of ​​the plate that can be used for driving nails.
3. The 4.0 x 40 mm corrugated nails should be placed as evenly as possible along the outer holes of the plate.

Rice. 11.11 Connecting the elements of the lower chord of the arches using bolts and one-sided lock washers with external teeth, clamped between the parts to be connected, as well as using washers

1. The junction of the elements of the lower chord of the arch.
2. Minimum distances are given in Table 11.2.
3. The thickness of the lining and the thickness of the elements of the lower chord of the arch must be the same.
4. Lock washers with external teeth - 2 pcs. for connection. The diameter of the lock washers is selected according to table 11.1.
5. Bolt, 20 mm.
6. Washer, 60×60×5 mm.

Rice. 11.12 Diagonal wind braces 23x98 are attached to each triangular arch

1. Diagonal wind connection.

Rice. 11.13 Diagonal wind braces are attached to the lower edge of the upper chords of the arch with 3 nails 2.8×75 or 3.4×95 mm

1. Attaching the diagonal wind brace to upper belt designs.

Rice. 11.14 Anchoring wooden arches with perforated steel tapes
Rice. 11.15 If there are arches on the installation path chimneys or other obstacles, then the arch is shifted to the side. An additional arch is installed on the other side of the obstacle

1. A triangular arch that should be moved to the side.
2. Additional triangular arch.

The material was prepared by designer Vladislav Vorotyntsev based on the Norwegian technology of frame house construction developed by the SINTEF Institute

The nail plate is used for fastening the rafter part of the house, as well as for connections in frame housing construction. It is a strip (plate) made from galvanized steel sheet with stamped nails (teeth). Production of nail plates using cold stamping method hydraulic press allows you to obtain high-quality connecting elements. Standard insert teeth are 8 millimeters high. One nail plate can have from 2 to 16 rows of teeth.

The thickness of the nail plate is from 1 millimeter, the width can be, depending on the standard size, from 20 to 132 millimeters, and the length can be from 76 to 1250 millimeters. Using metal gears connecting plates such wooden structural elements as boards, beams, beams lying in the same plane can be connected without the use of nails, screws and other fasteners.

Why fastening can be a problem

The issue of fastening is very important due to the characteristics of wood and its “behavior” depending on weather conditions. With changes in the degree of humidity, wooden building elements decrease or increase in size and are often subject to bending. As a result, large and long-term “stresses” arise in the places of their connections and abutments. The reason for this may also be the construction of a light foundation or its complete absence(which is possible given the low weight and elasticity wooden structures), leading to a change in the geometry of these structures.
When using a metal plate, increased corrosion resistance of the connecting element is ensured, which favors its operation in conditions high humidity, as well as when performing external work.

Properties of nail plate

The connecting nail (toothed) plate has important advantages in comparison with other types of fastenings. For example, from separately driven nails, each of which is on its own.
-*Strength of bonding with wood is achieved shape of the teeth and their angle of inclination, arrangement in rows. At the junction of wooden structural elements, the nail plate forms a connection that has high strength characteristics that no other fastening element can compete with. These indicators have been verified by many mechanical tests of structures.

-*Common monolithic platform– the base on which all the teeth are attached eliminates the possibility of their mobility and swinging. The platform becomes a common, connecting basis for the connected parts of the structure, due to which the connection is again given the quality of strength.

allow us to provide excellent strength even when splicing wooden structural elements by butt jointing.

-*Parts are attached extremely tightly. it's the same empirically proven. For example, a beam assembled using a plate of two butt-joined wooden beams, when exposed to a fracture, it broke not at the junction of the structural elements, but in the monolithic part of the beam. Thus, the monolithic nail plate platform completely prevents the teeth from moving or becoming loose and becomes reliable basis connecting node.

-*If necessary galvanic coating possible– This is a possible additional service at the request of the customer. This coating will give additional durability to the steel nail plate.

-*Metal toothed plates Install faster than traditional types of fasteners, thanks to its unique design. This will significantly save construction time. installation work for fastening elements of rafter and sub-rafter systems.

-*Due to the possibility of manufacturing floor beams with “corridors” specially designed for these purposes this method of fastening facilitates the laying of communications(ventilation ducts).

The listed qualities of nail connecting plates have become the reason for their widespread widespread use in the construction and construction of wooden structures for any purpose. The simplicity of the design of nail plates brings exceptional strength and durability to the connection.

Experience in using nail plates

Steel nail plates have been used for over twenty years in Canada and the USA, specifically in North America They began to be widely used in the construction of wooden structures. This fastening method is now widely used throughout Europe. With the help of industrially produced truss structures based on plates, you can build almost any type of roof, attic, attic spaces, skylights, etc.

Roofs using nail plates are applicable in all types of structures, for example:
- residential buildings,
-industrial,
- agricultural,
-sports and commercial facilities.

In addition to truss structures, this technology can be successfully used for:
- reconstruction of buildings and flat roofs, where plates are considered an indispensable type of fastener;
- production of panels for walls;
- production of lattice frames,
- construction of formwork for concrete structures,
- construction of long-span premises made entirely of wood.

The possibility of creating trusses with a span of more than 30 meters without internal supports (for example, tennis courts), which has arisen in connection with the use of connecting plates, is widely used. The plates can be successfully used when joining boards lengthwise.

Tooth (nail) plate is a strong, fast and economical connection for wooden structures. The distinctive advantages and properties of this fastening contribute to its increasingly widespread use in construction. wooden houses and structures in our country. The opportunity to purchase these products is becoming more and more accessible, and those interested can evaluate the convenience and quality of this fastener in practice.

Metal toothed plates (MTP)– these are steel elements with a thickness of 1...2 mm, which are obtained by stamping and have a working side sharp metal teeth different shapes and lengths

each of which has its own functional purpose, photo 1. MZP, thanks to its teeth, their shape, angle of inclination and location, provide high strength of fastening to wood.

MZP - application of plates, their types and characteristics, installation

Photo 1. Metal toothed plates

MZP are intended for the installation of roofing and other structures made of wood. minimum wages have optimal thickness, shape and number of teeth for the construction of structures with the following spans:

• up to 12 m – roof trusses, interfloor trusses;
• up to 30 m – arched and frame structures;
• up to 10 m – beams.

You should know that mainly designs using MZP are carried out in industrial conditions. This is especially true for such structures as:

• Wall panels;
• floor beams;
• covering trusses.

This is explained by the fact that in production it is possible to easily fix structural elements in the exact design position, and allows robots to perform high accuracy(±10mm) and quality. Photo 2 shows the design components using MZP.

Photo 2. Assemblies and structures using MZP

To accurately fix structural elements at the enterprise, it is necessary to use the following equipment:

• hanging press bracket with conductor;
• mobile press;
• stationary press.

Metal toothed plates are made of galvanized cold-rolled steel. The steel has a zinc coating with a thickness of 14...17 microns.

Metal toothed elements are used not only in industrial housing construction, but also in private ones. Also, using the MZP, you can perform the device wooden formwork and production of packaging containers.

The main types of MSP are divided depending on their thickness, and the thickness determines the width of the plate and its scope of application with different sections of beams. Most manufacturers produce MZP of three thicknesses: 1; 1.2; 2 mm, tab. 1. Below are their main parameters.

Table 1

Types of minimum wages

	Position	MZP-1.0	MZP-1,2
	Purpose	For connecting elements up to 38 mm thick	For connecting elements up to 60 mm thick
	Material	Cink Steel	Cink Steel
	Plate thickness
	Plate width
	Plate length	Any length multiple of 25 mm starting from 50 mm (at customer’s request)
	Additional plate sizes	width: 45; 54; 63; 81; 108 mm; length: 45; 70; 95; 120; 145; 170; 195 mm (for each additional width plate)
	Tooth height

There are MZPs that can be used to connect wooden beams with a thickness of 70 mm or more. Manufacturers offer the following plates depending on their thickness:

A) with a thickness of 1.2 mm:

• length – 160…340 mm;
• width – 80…140 mm;
• teeth length – 14.8 mm.

B) with a thickness of 2.0 mm:

• length 160…400 mm;
• width 80…200 mm;
• teeth length - 23.5 mm.

Depending on the country of manufacture, minimum wages may differ:

• according to the material of manufacture;
• by shape and number of teeth;
• plate thickness.

In MZP elements, the teeth are located very often to ensure that the wood works for crushing and not for chipping. The density of teeth can reach 70 pcs/dm2.

Minimum wages are produced with:

• unidirectional arrangement of teeth (Russia);
• bidirectional arrangement of teeth (Poland, Finland, Germany).

The most common design of MZP plates with unidirectional teeth is a slight shift of adjacent longitudinal rows relative to each other. The main disadvantage of plates with unidirectional teeth is the different strength and deformability of the teeth, the value of which depends on the angle between the axis of the plate and the axis of the force, as well as the angle of direction of the wood fibers to the axis of the force. However, there is a more improved design of the MZP, in which the teeth have different directions - parallel to the sides and diagonals of the square (it turns out to be a “herringbone”).

The most common minimum wages in the construction market are the following types (systems):

• Ganges Neil (Europe);
• MZP-1.0; MZP-1,2 and MZP-2 (CIS countries);
• Arpad (Hungary).

Feature of the system Arpad is the arrangement of teeth in rows with different angles, directed towards each other, so that when pressed into wood, they become jammed and the overall strength of the connection increases.

The types of minimum wages considered to be the most effective Gang Neil And Arpad, however, every year the design of metal toothed plates is increasingly improved by leading manufacturers.

The main characteristics of the MW are given in table 2, 3.

table 2

Main characteristics of connections from MZP

Designation	Stressed state of connection	Characteristic angle α, β, γ hail	Calculated load bearing capacity connections with plates type
			MZP-1,2	MZP-2
R (MPa) working area of ​​connection	Wood crushing and bending of teeth at angles between the direction of the fibers and the acting force β
Rр (kN/m) width of the working section of the plate	Tension of the plate at the angle between the longitudinal axis of the plates and the acting force α
Rav (kN/m) length of the cut section of the plate	Shear of the plate at the angle between the longitudinal axis of the plate and the direction of the shear force γ

Table 3

Design load-bearing capacity of MZP

Type of stress state	MZP thickness, mm	Design load-bearing capacity R (kg/cm) at angle α in degrees
Stretching

Installation of MZP plates

For one simple connection two plates are needed - one on each side. To obtain a connection with high strength, it is necessary to use a special press that fixes the exact position of the plates and ensures the required speed of pressing the teeth into the wood.

As noted above, the installation of the minimum wage and assembly of the main elements (structures) is carried out in the workshop, and then finished design transported by construction site, photo 3. The plates should be placed so that the rows of teeth are parallel to the grain of the wood of the element that absorbs high forces.

Photo 3. Manufacturing and installation of wooden structures with minimum wages

The main advantages of the minimum wage

1. Possibility of arrangement of connecting elements in one plane.
2. The overall wood consumption is reduced.
3. Relatively low weight of the entire structure.
4. The ability to install wooden structures without the use of special lifting equipment.
5. Relatively low labor intensity of installation work. Work on the installation of grooves and tenons in the elements is excluded.
6. Reducing financial costs when transporting and installing wooden structures.
7. High durability of MZP elements and structures using them.
8. The joints are relatively strong compared to adhesive and nail joints.
9. The optimal number of people for the construction of wooden structures with minimum wage is 4...5 people.
10. Possibility of constructing wooden structures of any complexity.
11. Exists software, which allows you to speed up the process of designing wooden structures, eliminating the possibility of making gross errors in calculating the strength of connections and selecting the required section of composite beams.

Photo 4. Main advantages of minimum wage

Main disadvantages of minimum wage

1. For the manufacture of wooden structures with MZP, a perfectly flat platform is required.
2. The need for special press equipment that provides the maximum and required joint strength. Manual installation MZP (press-fitting) is not recommended, as it significantly reduces the strength of the connection. The technology for constructing wooden structures using MZP is not widely used in private house construction, since it requires the use of special equipment and is almost always carried out in an industrial workshop.
3. Since the Gang-Neil systems are mainly used, one of the main disadvantages is miscellaneous work plate and his teeth in different directions.
4. When a load is applied to the plate along the main axis, its bending strength of the tenons will be minimal.
5. The weak point of the teeth of the plates is at the base, where minimum value bending rigidity.

Konev Alexander Anatolievich