One of the first metal roofing coverings was seam roofing. Having appeared centuries ago, it remains the most reliable type of roofing today.
General information
Seam roofing gets its name from the connection method. metal sheets. The German term "rebate" means "seam" or "gutter". It is with the help of such seams or locks that the fragments of such a roof are connected to each other. The edges of the sheets are folded and connected to each other in various ways:
- single standing seam;
- single rebated fold;
- double standing seam;
- double folded fold
Such locks ensure tightness roofing, its complete waterproofness, durability and aesthetic appearance.
Metal sheets intended for seam coating most often consist of several layers: a zinc coating, an anti-corrosion coating and a primer are applied one after another to a steel sheet base on both sides, after which it is covered with a layer of decorative polymer on top, and a layer of protective varnish on the bottom. .
Depending on the type of materials used, the following types of seam roofing differ:
- made of galvanized steel – has good anti-corrosion properties and lasts up to 30 years;
- made of galvanized steel with additional polymer coating- admits big choice colors, in addition protective function, also performs decorative;
- made of copper – has different textures, produced in rolls; lasts the longest - over 100 years;
- made of aluminum – resistant to deformation, temperature changes, lasts about 80 years;
- made of zinc-titanium alloy - resistant to corrosion, lasts about 100 years.
Advantages of seam roofing:
- tightness;
- minimum waste;
- usage roll materials allows you to make sheet length equal to length roof slope;
- fastenings are located under the covering; this does not violate the tightness and improves the appearance;
- fast and convenient installation.
Flaws:
- the roof requires good sound insulation, because otherwise during rain the noise will be too strong;
- roof equipment is mandatory, because the material accumulates static electricity, and this is unsafe during a thunderstorm;
- To work with folds, you need to find a specialist, since you cannot make a mistake during work.
Installation of seam roofing
To perform installation correctly, it is important to have a tool for clamping seam locks. It can be mechanical or electrical. In the second case it is professional tool, capable of rolling up a double standing seam in one step. Self-latching seam roofing also exists today. Choosing such a roof will greatly facilitate installation work.
In addition, you will need a hammer, pliers, an electric drill, nibblers, metal scissors, a screwdriver, a mallet, and measuring tools.
Installation procedure
Installation of a seam roof begins with the selection of sheathing, which can be sparse (with the required design pitch of 30-40 cm) or continuous, from wooden beam 50x50, boards 32x100 or metal profile. Its main feature should be ideal Smooth surface, without recesses and protrusions, with minimum slope 7°. Wooden sheathing To protect against rotting, they are impregnated with antiseptics, painted or covered with drying oil. If panels with a self-latching rebate are used, then the sheathing is made of metal.
Thermal and waterproofing is attached to the sheathing so that the seam is reliably protected from corrosion.
A cornice is fixed along the lower edge of the roof slope, and valleys are attached to the sheathing (only the bottom one is used).
Then they prepare steel sheets: they are marked, cut and connected into sheets equal in length to the roof slope, but not more than 10 m.
On next stage Workpieces are lifted onto the roof and the roof is installed. Roofing sheets are attached to the sheathing using clamps - narrow steel strips, one end of which is fixed to the sheathing, and the other is inserted into the standing seam. The canvases are fixed in pairs by compaction. All parts (screws, clamps, etc.) must be made of galvanized steel. Smoke and ventilation pipes are also formalized by her.
A ridge is installed on the finished roofing deck at the upper edge of the slopes, securing it with roofing screws to the top edge of the rebate lock. The ridge can be semicircular or flat.
In those places where the roof is adjacent to walls, pipes and dormer windows, install a wall profile.
For a seam roof, a mandatory step is. It is best to choose tubular ones, fixing them on bracket supports that are attached to standing seams. With this method of fastening, the integrity of the sheet is not compromised, which means the roof’s tightness is maintained.
Subject to installation technology, proper work and use quality materials, a seam roof will not cause any trouble or problems for its owners for a very long time.
Main characteristics
The double interlocking standing seam system provides a lightweight, stable and highly durable roof covering and is widely used on many various types buildings including education, health, sports, commercial, religious and of course housing. The system is suitable for pitched roofs between 3º and 90°, vaulted roofs, conical and domed roofs, and in general almost any type of roof that can be coated with elZinc®.
This traditional system, which has been used for zinc installation since the origin of zinc roofing itself and continues to be by far the most popular method today. Fine lines of permanent seams give the system a light, attractive appearance and will contribute to its flexibility. Modern technology does fast work large roofs, reducing installation time and associated direct and indirect costs.
It can be installed in both ventilated and non-ventilated roof structures, allowing you to choose best solution according to the characteristics of each project. The fastening is hidden and indirect. Requires constant maintenance and usually uses elZinc® sheets with a thickness of between 0.65 and 0.8 mm. The coating can withstand a certain amount of foot movement.
Standing seam diagram
- Standing seam tray
- Height 25 mm.
- Fastening clamp (sliding)
Basic connections
Longitudinal seam height 25 mm double lock standing seam. The lock is raised above the drainage part of the tray.
Standing seams are formed by profiling or folding elZinc® strips and sheets into trays. It is formed along one edge (this is the edge that is attached with clips) and overlapped along the other. To make the joint, the last seam around the tray is adjacent, covering the clips. The two trays are then seamed using a seaming machine. 70 mm of material used to form a seam.
Angle seam joints are limited to use at angles of at least 25o or higher. Double standing seam is rated to weatherproof above 7° without sealing, and at or above 3° when sealed. This is usually done with closed cells using self-opening seals.
Permanent seam
Overlap fastening
Small gap in basic shapes
Angle joint standing seam
Double standing seam
joint
Self-expanding on
sealing tape
Double standing seam
joint
Cross connections
Sometimes it is necessary to attach the folded trays at the ends. Without going into too much detail in this document, this could be to introduce an expansion joint on 'long' roofs (long eaves), as part of work around a chimney or clerestory, or to make changes to the width of the tray on a tapered roof, for example. Generally speaking, the type will depend on the pitch of the roof slope, as shown here.
Save at a stage where none of the components require any changes to the design of the substrate or side face/side support detail. The released joint, however, requires a 60mm high jump to be created on the substrate, either by removing the entire top of the roof or by creating a fillet in the top surface. In any case, the stage profile can be hidden by creating a small parapet (H = 100 mm) along the side edges of the roof to hide the step inside external profile edges.
Step
Pitch: 3º and above
Height: 60mm
Often used as a compensator on long, low pitched roofs. The step in the substrate can be formed using fillets. Bottom Roof Tray Continuous fixation of "T" plate strip with folded rear edge of top roof tray expansion/compression gap
Double lock cross welt
Pitch: 7º and above
Width: About 20mm
Pre-slide type (as shown here) allows for excellent rainwater drainage (traditionally stamped joints can retain rainwater at low pitches). Neither version works as a compensator. Lower roof tray Upper tray
Circular lock
Pitch: 10º and above
Circle: About 180mm
Often used as a compensator on long roofs. The lower tray of the roof solders the continuous strip of the upper tray for expansion/compression at break
Single cross welt lock
Pitch: 25º and above
Width: 40mm folded, 30mm on top tray. Can be used as an expansion joint on long roofs 40mm bottom roof tray folded Top tray expansion/compression gaps
Fixation
Concealed fastening is indirect, using clips that cling to the seam and are (usually) threaded or nailed to the backing below. If the length of elZinc® trays is under 1.5m, fixed rollers can be used throughout. Trays over 1.5m will require a combination of main clips and sliding clips to provide thermal movement of the trays, and will also require provision for movement at the eaves and ridge.
These clips should be sufficient in line with the design to resist wind loads for each project. Typically 6 clips per sq will be sufficient for buildings no taller than 8m, while corners and edges of tall buildings will require more - see our technical data sheet documentation for more information detailed information.
Fixing clip and moving clip
Dimensions
Since the pallets are fixed only along their seams, the spacing between them is determined according to the expected wind load, and is related to commercially available coil widths.
The location, exposure, orientation and geometry of the roof are all influenced by wind uplift. elZinc® or an installer familiar with the area should be consulted when making decisions about center seams. This is not only to ensure that the roof does not suffer during storms, but also to prevent the trays from fluttering in constantly windy weather.
These widths are used in combination with different thicknesses from 0.65mm to 0.8mm to ensure the roof meets all the performance criteria for which it is intended.
The maximum length of the tray is nominal 10 m, however this can be slightly increased by flat roofs(without additional measures required) or using special clamps that allow greater movement, a maximum of 15 m.
The distribution of the main clips depends on the roof slope - the steeper the pitch, the higher the group of main clips is positioned. This means that the lower the roof height, the narrower the trays, before an expansion joint can be inserted or special measures must be taken, for example the use of special sliding clips.
Installation
The system is installed from left to right or right to left across the entire width of the deck or on both sides of the central "female-female" tray. The latter option ensures the same width of the trays and therefore symmetry on both sides of the lid. Our publication "elZinc ® Parts, Fabrication and Installation" contains detailed installation information and can be downloaded from our website.
The installation itself must be carried out by a specialist and reliable contractors. elZinc® on request, contact information for suitable contractors.
Appearance
The seam should always, if possible, be in the fall line. By themselves, the boards are quite thin, but on a sunny day the shadows cast are clearly visible on the surface of the cover. Unique feature thin sheets metal roofing is the appearance of subtle undulations in trays under certain lighting conditions that provide a bit of "vibration" and "energy" to the building.
Many architects appreciate this effect being most noticeable on steep roofs (attics) or facades. However, if desired, it can be minimized if our elZinc® material: excellent flatness and low level residual stresses produces very flat trays that minimize these irregularities. Other measures that can be taken to reduce shadows:
. Using elZinc® 0.80 mm thick.
. Narrow tray width 430 mm
Rain drainage
Rainwater flows down inner or parapet gutters or hanging gutters, usually made of zinc. They can be installed horizontally, but down 1 in 200 is recommended as this promotes self-cleaning and increases its flow capacity.
Gutters are installed in such a way that thermal movement occurs between each other and adjacent cover trays, since along each section of the gutter, second, introducing expansion joints.
You must protect the snow slide gutters from the roof by placing steam-snow. In cold climates, installation of electric heating cables is recommended in areas where ice may accumulate.
For more detailed information on the size and design of gutters, see our technical documentation.
Roofing forms
Cover shaped like a barrel vault
Seam trays bend under their own weight within a radius of about 20 meters. Steeper curves require pre-bending (possibly up to a minimum radius of ≈ 40 cm). The trays are mounted on top of the cross tires, unventilated or ventilated, and on or very close to both sides of the ridge in the case of a ventilated roof in the ridge. Here, the slope of the trays should allow water to flow freely from each side of the ridge, and the third to the first meter of tray is recommended. Seams must be sealed in housing ways with less than 7º.
Parallel curved tray
1. Fixed axis area
2. Fan ridge
Conical roof
Conical seam trays accept this type of covering is used. The minimum between the axes of the joint depends slightly on the profiling apparatus used, but is between 50 and 100 mm. The lid is placed on top. If the cap comes out through the outlet at the top, the small outlet section should be checked - see our technical literature. The fixed pin strip is positioned according to the roof slope.
Conical roof
1. Fixed axis area
Open conical roof
The same type of tray and the same locking method are used here as with the conical roof. If the cover has an opening through the air intake into the eaves, the minimum cross-section must be checked. The strip contacts (omitted in this diagram) are positioned according to the slope. This type of pan concentrates rainwater under the eaves, and this must be taken into account when designing the gutter to prevent it from flying over the leading edge.
Conical plate
Domes
Trays usually need to be made after taking measurements on site to determine its exact shape (the degree of bending along the seams) and its dimensions. Small domes can be built and removed from the site before being placed in the desired position. It should provide adequate separation for air to escape at the top. Please take a look at our technical literature.
Curved tray
Roof installation and construction
Seam trays are not self-supporting and require continuous or almost continuous support to rest and against which its contacts are secured. The support may be vented or unvented, but in either case it is important to be installed correctly to avoid the risk of potentially harmful interstitial condensation to the cover. Our technical publications provide more detailed information on this topic. In ventilated wooden flooring used for support in the form of pallet wood or pine, plywood or OSB external class 3. Minimum thickness substrates 22 mm to 18 mm stage and in plywood and OSB.
These materials should be installed perpendicular to the direction of the pastures together. If there is any doubt regarding the extraction values of pins fixed in OSB, a test should be performed to confirm that the minimum value of 560 N from the fastening type suggested will be achieved.
Can also be used wooden supports unventilated covered, but the need to reduce thermal bridges has led in many countries to the use of hard thermal insulation boards, insulating joint boards and sandwich panels, as direct support within the zinc framework. Rigid insulation is used in combination with special pins that pierce the insulation and screw into the base underneath. Used in Thus, the thermal insulation must be able to withstand the transit of installers, and not deteriorate during the entire life of the building.
The insulating panel joints provide the wood with a base for the zinc (factory bonded insulation), so that the zinc is installed using pins and traditional fixings.
Three examples of the many possibilities that exist are shown here. For more information about these and other types of construction packages, see our technical documentation or contact our consulting services.
Ventilated roof
- elZinc® seam
- Function Drainage membrane
- Direct support
- Wood slats
- Chamber ventilation
- (Optional) breathable sheet
- Wooden rafters
- Insulation between rafters
- Lamina steam control with closed slabs
- Interior decoration
The height of the ventilation chamber must be at least 5 cm, and in some cases (low slope, long distance between the cornice and the ridge) should be increased to 10 cm - see our technical documentation. Direct support can be wood flooring, boarding or plywood or OSB, all parallel to the eaves and studded together. An optional breathable membrane provides additional protection isolation from cold currents, driven by the wind, entering vent from the outside.
Insulating Composite Ventilated Cover Sheet
- Cover seam elZinc®
- Membrane with drainage function
- Composite thermal insulation panel
- Corrugated Backing Sheet
A composite insulating plate (factory bonded) is screwed through the vapor barrier to the corrugated support sheet. The vapor barrier must be of high performance self-sealing against these fastenings and all circles and passages must be closed. Outside surface insulation must be plywood or OSB for external use, class 3, with a thickness of at least 18 mm. The vapor barrier performance has important in this design.
Cover of unventilated - "quickly-warm"
- Cover seam elZinc®
- Printing with drainage function
- Fastening type "Warm fast"
- Rigid insulation
- High performance vapor barrier
- Support
- Cabio
- Interior decoration
High performance vapor barrier, the effectiveness of which is important in this design, self-seals against “warm quickly” type fixations. All matches and passages must be closed. The support can be made of wood or steel. Center standards are applied to the contacts, but the zinc is only secured by the screw pin. Therefore, it is necessary to ensure sufficient recovery value
Note: The colors shown here are illustrative only and should not be considered as real. To see actual finishes, request a letter of finished elZinc®.
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Reclining and standing seams. Pictures are made for ordinary covering of roof slopes, eaves overhangs, wall gutters, gutters, etc. The picture is an element of the roof covering, the edges of which are prepared for a seam connection. Usually they are made of two sheets (85...90%), less often single sheets (10...15%) for additives in row strips. Roofing sheet steel for preparing paintings must have smooth planes; all angles must be right. The roofer prepares seam joints on a workbench, the shield of which is edged on one or both sides with angle steel. Seam connections according to appearance They are divided into recumbent (Fig. 167, a...d) and erect (Fig. 167, e...i), and according to the degree of compaction - into single and double. (The dimensions of the folds are given for sheets with a thickness of 0.45...0.7 mm. For thicker sheets, the folds are increased by 20%.)
Rice. 167. :
a - bend of the edge for a single recumbent fold; b - connecting sheets with a single recumbent seam (the dotted line shows a sheet with an undercut); c - edge bend for double rebated fold; d - joining sheets with a double folded fold; d - bends in edge sheets for a single standing seam; e - joining sheets with a single standing seam (comb); g - bends in edge sheets for double standing seam; h - intermediate bend for double standing seam; and - completed connection of sheets with a double standing seam (ridge)
Roofing sheets are connected one to another along the short side of the sheet with lying seams, and along the long side with standing seams (ridge seams). When covering roof slopes, standing seams are placed along the slope, and recumbent seams are placed across (parallel to the roof ridge), which does not interfere with the flow of water from the slopes. Seam connections can be single or double.
A single lying fold (Fig. 168) is performed as follows. The sheet is laid on the edge of the workbench and a line is drawn with a scribe to bend the folded edge. To prevent the sheet from moving, hold it with your left hand. First, at the corners of the sheet, two beacon bends are made using a mallet along the score (Fig. 168, a), for which the score is combined with the edge of the corner on the workbench. Then, at the risk, the entire edge is bent (Fig. 168, b), the sheet is turned over and the bent edge is dumped onto a plane (Fig. 168, c, d). The edges on the second sheet are prepared in the same way. After this, the sheets are connected into a lock (Fig. 168, d) and compacted with a mallet. To prevent the fold from moving apart, it is cut with a metal strip and a hammer (Fig. 168, e).
Rice. 168. :
a - laying the sheet on the workbench with securing its corners; b - bend of the entire edge by 90°; c - edge prepared for dumping; d - falling of the edge onto the plane; d - joining sheets with a seam and sealing it; e - seam undercut
A double rebated fold is formed like this. The first four operations are performed similarly to the formation of a single fold. The prepared edge is then bent down 90°, the sheet is turned over on the workbench with the bent edge up and the fold is laid flat. In this way the second sheet is prepared. The prepared edges of the sheets are pushed one into the other, after which the fold is compacted with a mallet. The fold is cut using a strip and a hammer (Fig. 168, e).
A single standing seam is formed using a comb bender and a mallet (Fig. 169, a...g). First, the edge of the bending scraper 1 is brought close to the high edge (Fig. 169, a) and with a mallet it is dropped onto the plane of the scraper (shown by the arrow). Then, having removed the comb bender, use a mallet to tilt the edge downwards (Fig. 169, b), and use a block 2 to install the comb bender close to back side fold (Fig. 169, c) and compact it.
Rice. 169.
a - bend of the edge; b - bending the edge with a mallet; c - fold seal; g - bend of the edge of the double standing seam; d - double standing seam seal; e - folding and compaction of a double lying seam on a plane; 1 - comb bender scraper; 2 - comb bender block; 3 - plugs; 4 - steel strip; arrows show the direction of blows with a mallet
To create a double standing seam, the comb bender is installed on plugs 3 (Fig. 169, d). The edge of the bending scraper is brought close to the high edge and, using a mallet, it is dropped onto the plane of the scraper. Then the operation is repeated (Fig. 169, b, c). Comb bender 2 is installed close to the back side of the fold and compacted (Fig. 169, e). The last operation is to knock down and compact the double recessed seam with a mallet (Fig. 169, e). After this, the fold is folded and compacted (Fig. 169, e).
The folding machine (Fig. 170, a) has two squares 1, to the bent shelves of which cheeks 6 are welded. The cheeks are connected to each other by a square 9. A longitudinal recess is made in the horizontal shelf of the square 9. A bending square 10 is attached to the vertical shelf of the square 9 with hinges 14. The horizontal shelf of the bending square is in the same plane with the base of the recess of the square 9. A bracket 11 is attached to the horizontal shelf from below, which rotates the square and two stops 8.
Rice. 170. :
a - machine; b, c, d - sequence of edge bending; 1, 4, 9, 10 - squares; 2 - spring; 3 - rod; 5 - strips; 6 - cheek; 7, 11 - staples; 8 - emphasis; 12 - traction; 13 - pedal; 14 - hinge; 15 - sheet
On internal sides cheeks 6 there is a movable device of the machine, which consists of two movable rods 3, rigidly connected to each other by a pressing square 4. The horizontal shelf of this square is made in the form of a wedge, under which a longitudinal strip 5 is attached for crimping the edge of the roofing sheet in the longitudinal recess of the square 9. Guides for the rods there are brackets 7 and through passages at the ends of the horizontal flange of the square 9. The movable device of the machine is held in the upper position by means of springs 2, in which it is convenient to insert the sheet into the machine and remove it after bending the edge. A pedal is mounted on square 10, consisting of a pedal bar 13 and connecting rods 12.
The machine is installed on the workbench so that the horizontal shelf of the square 9 is in the same plane with the working plane of the workbench. To bend the edges of the lying folds, standard sheet 15 (Fig. 170, b) is placed on the workbench so that the edge of its narrow side is flush against the stops 8, and press the pedal with your foot. As a result of pressure, a small depression is formed on the sheet (Fig. 170, c). Using bracket 11, turn the bending angle, which bends the edge of the sheet to a given angle (Fig. 170, d). After bending the edge for the fold, the pedal is released: in this case, the movable device, under the action of springs, rushes upward. At the same time, the bending angle is retracted to its original position. At the moment of lifting the movable device, the sheet jumps off the pressing square. After this, the sheet is turned over 180° and the fold edge on the other side of the sheet is folded in the same way. From the manufactured single paintings, double paintings are assembled. Assembly is performed manually or on a VMS-61 folding machine. The assembled picture is fed to a large folding machine.
Large folding machine designed by I.P. Prokhorov (Fig. 171) works like this. The painting is placed on the workbench 2 so that its large side comes close to the rear stop rail 1. The other large side of the painting should be positioned so that its edge extends 20 mm outward from under the clamping square 5. Following this, the edges of the painting are pressed against the square by 4 workbenches. Then, using levers 8, the bending angle 5 is turned, which bends the edge of the small standing seam. Since the bending angle is shorter than the pressing angle, the corners of the picture remain uncrimped. In this case, the pre-bent edges for the recumbent folds do not wrinkle.
Rice. 171.
1 - thrust rack; 2 - workbench; 3 - support stand; 4, 5, 9 - clamping, bending and stationary angles; 6 - pressure screw; 7 - stops; 8 - lever
At the end of this operation, the bending square is retracted to its original position and the pressure square rises upward, and the picture is pulled out of the machine until it stops 7. Then the pressure square is lowered again onto the edge of the picture lying on the workbench. After this, levers 8 turn the bending angle away from you along with the painting. As a result, the edge of a large standing seam with a height of 35 mm will be bent in the picture.
A small folding machine is used to bend edges on the short sides of sheets. On a frame made of angles, a clamping angle with a plate welded at the bottom is fixed. Raise and lower the pressure angle with the pedal. A sheet of roofing steel is laid on the machine table and inserted with the short side under the clamping angle with the edge of the sheet extending outward to the width of the rebate to the stop pins located on the bending bar. By pressing the pedal with his foot, the roofer clamps the edge of the sheet with a corner and, then rotating (by the bracket) the bending bar, bends the edge for the lying seam. After this, lowering the pedal, the roofer releases the sheet, turns it around and places it on the left half of the table, where the second roofer, using the same machine, bends the edges for the rebated seam on the other side of the sheet. The sheets prepared in this way are connected in pairs to form pictures. The work is performed on a roller drive machine. A roller drive machine is used to connect two sheets of roofing steel into a picture. In the center of the machine there are two rollers located one above the other, mounted on two shafts. The rollers are driven by an electric motor (via a gearbox) through a belt drive and a gear system. The roofer connects two sheets together with bent edges and pushes them between the rollers, which compact the rebated seam. Then the edges are folded back for the standing seam.
Corner seam connections. Corner seam connections are used when making roofing parts such as caps and umbrellas for chimneys, as well as in the manufacture of household equipment. The connection of two sheets with a simple corner fold begins with bending the edges at 90° (Fig. 172, a), and one of them is laid on the plane of the sheet (Fig. 172, b). Then, placing a sheet with an edge bent upward on the workbench, insert it into the gap formed by turning over the edge of another sheet (Fig. 172, c). After compaction, the resulting ridge is dumped onto the plane of the first sheet (Fig. 172, d).
Rice. 172.
To connect two sheets with a combined corner fold, the edge of the sheet removed from the workbench (Fig. 172, e) is bent by 30° and a break is made in it (Fig. 172, f). Then, turning the sheet over on the workbench, the resulting fracture is dumped onto a plane (Fig. 172, g) and the edge is bent, forming a double recumbent bend (Fig. 172, h). After this, the sheet with a double bend is placed on a workbench (Fig. 172, i) and the previously bent edge of another sheet is inserted into the slot of the second bend. Finally, the vertical edge on the bend of the first sheet is dumped onto the plane of the second and compacted on both sides on a metal support. The width of the edges in sheets connected by corner folds depends on the thickness of the sheets. For simple corner connections 5...6 mm is enough, and for more complex edge widths 14...16 mm are taken.
We will analyze the sequence of operations when installing a double corner fold using the example of inserting a bottom into a rectangular box. Edges are drawn to the bottom according to the dimensions of the box to form folds and the corners are cut off. After this, along the dotted lines in the bottom, all edges are bent in one direction, on the edges they are made in external sides narrow bends. Then the corners of the box are cut and the bottom is inserted into it. The bottom flaps are placed on the sides of the box, using a mallet and a metal stop. Next, the box is placed on a workbench and all overhanging edges of the single fold are sequentially aligned and bent by 90°. Finally, the edges are dumped onto the side walls of the box and compacted. In the manufacture of various roofing elements, as well as household equipment, the roofer has to connect the parts not only with straight angular, but also with curved folds. Curvilinear folds connect round and angled pipes. The design of a curved rebate is the same as that of a straight one. An additional operation for curved seam joints is flanging. It consists in expanding the folded edge due to thinning its thickness. The production of curved folded joints is called folding.
© 2000 - 2003 Oleg V. site™
A modern folding machine is used to create blanks for different types folds I will tell you step by step about the principle of operation, types and popular models of machines, and also explain how to make a folder with your own hands.
Production technology
The seam-rolling machine is indispensable both for arranging the seam roof itself and for the production of auxiliary roofing accessories. This includes elements drainage system, front and end roof overhangs, and also with its help they make galvanized ventilation ducts.
Types of folds
A seam connection is a twist between two adjacent sheets of metal, and in order to arrange this twist, you need to bend the fold along the edge of the sheet, and it is precisely to bend this fold that you need a seam rolling machine.
There are 2 folded joints - these are single and double folds, plus folds can be standing or lying.
- Single fold is considered the basis, here one sheet is simply bent at 90º, and on the second sheet a kind of hook is made and after joining this hook is crimped;
- Double fold can be called an analogue of a single one, only the twisting is done in 2 turns. To wrap the metal this way, the size of the hook in the workpiece must be smaller, on average about 5-7 mm, and the height of the workpiece must be, on the contrary, larger.
As for the recumbent connection options, they are exactly the same as the standing ones, only turned to one side.
Nowadays, L-shaped roofing seams are quite common; there is no practical benefit from such a connection, it is no better or worse than a double bend, but many believe that the roof looks much more impressive this way.
When selecting equipment, keep in mind that there are machines for arranging recumbent folds, standing folds and universal units that can be adjusted as necessary to any type of bend.
General information about machines
The main advantage of a seam roof is that the covering is monolithic, without any fastening or connecting holes. But the roofing metal itself is quite thin and making blanks in production and then transporting them to the site is inconvenient and often unrealistic.
A small folding machine makes a big difference. With such equipment, you can make blanks directly on site; moreover, there are models that can be installed directly on the roof.
There is one more important nuance: to bend the edges of sheets, a folding machine is needed, and to make a double fold and crimp the connection, bringing it to the final result, a folding machine is used.
Often the thickness of the metal for roofing works fluctuates around 0.5-1 mm, with a maximum of 1.2 mm. But good machine for a seam roof it is calculated for working with metal from 0.3 to 1.5 mm.
Such equipment is already closer to professional, and it can be used to make not only roofing paintings, but also to bend blanks to fit various kinds drainage or ventilation pipes, plus making valley gutters and ridge caps.
By the way, the blank for a seam roof (a strip of roofing metal with curved seams) is called “Picture” among professionals.
The very principle of operation of the unit is simple: any folding machine has a number of crimping shaped rollers, which actually bend the edges of the sheet. Crimping rollers are installed in pairs on crimping shafts.
The number of such crimping shafts may be different, but no matter how many there are, they are driven by a gearbox, and the gearbox itself rotates thanks to an electric motor. Of course, there is equipment with manual drive, but the productivity there is very low and such devices are rare.
Most popular models
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« ILMAKSAN KM 7.3»
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« METAL MASTER MLC 12 DR-T»
It can bend both standing and lying seams; in addition to roofing pictures, this machine can be used to make ventilation pipes. |
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« Metal Master FDS 1250» Manual folding machine.
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« MetalMaster GLF А4С» Universal folding machine.
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« SBD4C»
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« SPF 700»
The folding machine of this model is much lighter and smaller than its analogues, which allows it to be used directly on the construction site. The unit includes a roller stand for feeding rolled metal into a coil. This stand can support up to 1 ton.
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How to assemble the machine yourself
Not every craftsman can afford a folding machine, so quite often people assemble such devices by hand. A homemade folder, of course, does not have such a wide range of functions, but it will cost only 2–3 thousand rubles.
| Illustrations | Recommendations |
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Appearance.
Our homemade folding machine is designed for use in a workshop. This device is screwed to wooden workbench, but if you weld the legs for it, then this machine can be easily transported. |
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Device.
The whole structure consists of 3 parts. In the photo on the left, the arrow points to the base part, everything is welded and screwed to it.
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Scheme.
First, the front structure is screwed to the base corner, that is:
It was not in vain that a band saw blade was chosen for the crimping tooth; a particularly strong, inflexible metal is needed here. |
Rebates can be prepared manually and on machines.
When preparing folds manually, the following tools and devices are used: a mallet-hammer made of hard wood (birch, beech); roofing hammer of a regular shape; roofing hammer with a wide head; chisel; mandrel for folds; steel bar; straight and oval jambs; support; channel or corner mounted on a workbench (Fig. 91).
Rice. 91. Hand tool for tinsmith works:
a - mallet; b - roofing hammer; c - roofing hammer with a widened head; g - support; d - straight jamb; e - oval jamb; g - mandrel for folds; h - universal hand mallet-hammer: 1 and 2 - body; 3 - handle; 4 - screw; 5 - plug-in bosses; 6 - nut
Straight folds are prepared manually on a corner, on a block or on a channel attached to a workbench, by bending the sides to the required width.
The width of the folded edges on sheets of roofing steel with single lying seams is equal to: for seams with a width of 8 mm - 7 and 6 mm; 10 mm - 8 and 7 mm and 12 mm - 10 and 8 mm. The width of the folded edges with single standing folds is equal to: for folds with a width of 8 mm - 7 and 14 mm; 10 mm - 8 and 17 mm; 12 mm - 10 and 20 mm.
The dimensions of the allowances for single standing seams are thus equal: for seams 8 mm - 21 mm; 10 mm - 25 mm and 12 mm - 30 mm.
The preparation of a single lying seam is carried out as shown in Fig. 92.
Rice. 92. Sequence of operations for preparing single folds
On a sheet of roofing steel, a mark is drawn with a scriber (Fig. 92, item 1) at a distance of 7 mm from the edge for a fold 8 mm wide; 8 mm - for a fold 10 mm wide; 10 mm - for a fold with a width of 12 mm.
Then the sheet is moved on the workbench so that the mark aligns with the edge of the corner, and the edge is bent down with a mallet.
If the worker has skill in making folds, then they do not draw a line, but move the sheet beyond the edge of the corner to the required width of the fold by eye. To prevent the sheet from moving when bending the edge, make a bend at both ends, holding it with your left hand and pressing it to the edge of the corner.
After bending the edge, the sheet is turned over with the edge up (pos. 2) and with a mallet it is bent ("filled") to the sheet without compacting the fold (pos. 3).
In the same way, bend the edge on the second sheet, then insert one folded edge into the other (item 4). Then the fold is compacted with a mallet. To prevent the fold from coming apart, undercut the sheets at the edge of the fold with a mallet (pos. 5) or crimp the fold with a fold mandrel (pos. 6).
a) Preparation of a single fold with clamps
To strengthen the seam of a single seam, it is often reinforced with additional strips of roofing steel measuring 80x30 mm, which are called clasps. The clamps are placed on the rebate every 500-700 mm. To prepare a single fold with clamps (Fig. 93), the fold is prepared as indicated above.
Rice. 93. Sequence of operations for preparing single folds with clamps
A clamp bent in half (pos. 4) is inserted into the bent edge of the sheet, one end of which is bent over the edge of the sheet. Then the curved edge of the second sheet is inserted into the curved edge of the first sheet and the other half of the clasp is folded onto it (item 5). After this, the fold is compacted and an undercut is made.
b) Preparation of a double sliding fold
With a double sliding fold (Fig. 94), the width of the allowances for folded edges is taken as follows: for folds with a width of 11 mm - 30 mm; width 13 mm - 43 mm. The width of the rebate, as in single rebates, depends on the thickness of the steel.
Rice. 94. Sequence of operations for preparing a double sliding fold
The production of a double sliding fold is carried out as follows. After drawing the marks (Fig. 94, item 1), the first bend is made on the sheet - an edge 5 mm wide is folded with a fold width of 11 mm or 6 mm with a fold width of 13 mm. Then, after bending, the sheet is turned over with the edge up and this edge is “filled” without compacting (item 2). After this, the sheet is turned over again and laid so that it hangs over the edge of the workbench by 7 mm with a fold width of 11 mm or by 9 mm with a fold width of 13 mm (item 3).
Then use a mallet to make a second downward bend with an angle (item 4) so as not to crush the first bent edge. Then the sheet is turned over again (pos. 5) and the bent edge of the double folded edge is bent with a mallet to the sheet at an angle of about 45° (pos. 6).
In the same way, a double folded edge is prepared on another sheet or on the other edge of a long sheet.
To check whether the double folded edge is crushed somewhere, make a cleaning tool (item 7) and pass it through the folded part of the sheet along its entire length.
To join, the sheets are pushed into each other with their curved edges, hitting the end of the sheet with a mallet (pos. 8), then compacted and the fold is cut (pos. 9 and 10).
c) Preparation of a double fold according to the method of L. A. Lapshov
The method of manufacturing a double fold, proposed by production innovator L.A. Lapshov, differs from that described above in that it eliminates the operations of pushing and turning sheets. This simplifies and speeds up the work. Lapshov's method is as follows (Fig. 95).
Rice. 95. Preparation of a one-and-a-half fold according to the method of L. A. Lapshov
A second sheet is inserted into the folded edge of one sheet (Fig. 95, item 1) and both sheets are moved to the edge of the workbench by the width of the folded part.
Moving the support along the curved edge, using a mallet from below, bend the edge of the sheet to the required fold width upwards until it stops at the support (pos. 2). Then, using a mallet, the bent part is “dumped” onto the sheet and compacted (item 3). After this, with a second blow from the mallet from below, the resulting double edge is bent upward until it stops at the support (pos. 4). Then they bend the top sheet through the fold to the end, compact it and undercut the fold so that both sheets are in the same plane (items 5, 6 and 7).
d) Preparation of a one-and-a-half fold according to the method of L. A. Lapshov
For a one-and-a-half fold, the width of the folded side, including part of the allowance attributable to the thickness of the fold, on one sheet should be equal to one and a half width of the fold, and on the other sheet - 3.5 times wider than the fold. Consequently, the entire allowance for a one-and-a-half fold is equal to five times its width. For example, with a fold 10 mm wide, the allowance is 10x5 = 50 mm.
The fold is prepared as follows (Fig. 96).
Rice. 96. Preparation of a one-and-a-half fold according to the method of L. A. Lapshov
First, using a mallet, bend down a side with a width of 22 mm with a fold width of 8 mm, 27 mm with a width of 10 mm, 36 mm with a width of 12 mm, according to the markings (Fig. 96, item 1).
Then this side is “piled” onto a sheet of steel and compacted (item 2).
After this, a mark is drawn on the folded edge of the sheet at a distance of 6, 8 and 10 mm from the edge with a corresponding fold width of 8, 10 and 12 mm and a second fold is made upward without turning the sheet over. To do this, the sheet is shifted, aligning the drawn mark with the edge of the workbench, and, moving the support along the mark, the double edge of the sheet is bent upward with blows of the mallet from below. The bent part is again “filled” onto the sheet without compaction (items 3 and 4).
On the second sheet, bend a single edge with a width equal to the width of the second upward bend on the first sheet (item 5). Then both sheets are connected by curved edges (item 6) and compacted with blows of a mallet. After this, using a chisel and a hammer, bend the free edge of the one-and-a-half fold (pos. 7) and use a mallet to “fill” it onto the fold. The fold is compacted and undercut so that both sheets are in the same plane (pos. 8).
e) Preparation of corner folds
The preparation of a corner single closing fold is made in the same way as the preparation of a conventional single fold (Fig. 97).
Rice. 97. Preparation of a corner single fold
To assemble the sheets and connect the corner fold, a sheet with a bent standing edge is placed on the edge of the workbench and a second sheet with a bent bent edge is pushed onto it (Fig. 97, item 1). Then, using a mallet and support, the fold is compacted, “filled” (pos. 2) and leveled (pos. 3).
In a corner combined fold (Fig. 98), the width of the folded side of one of the joined sheets is equal to the width of the fold, and of the other - triple the width, therefore, the entire allowance is equal to four times the width of the fold.
Rice. 98. Preparation of a corner combined fold
The sequence of manufacturing a combined corner fold is as follows. First, using a mallet, bend down according to the markings (Fig. 98, item 1) a side 15 mm wide for a fold of 8 mm, 19 mm for a fold 10 mm wide, and 22 mm for a fold 1;2 mm wide. This board is “filled” on the sheet without compacting it with a mallet.
Then, on the bent edge of the sheet, a score is drawn at a distance from the edge of 8, 10 and 12 mm with a corresponding fold width of 8, 10 and 12 mm, the edge of the sheet is moved to the score at the corner of the workbench and the edge is bent downwards with a mallet (item 2). After this, the sheet is turned over and the edge is “filled” onto the sheet (item 3).
On the second sheet, bend an edge at a right angle with a width of 7, 9 and 11 mm with a corresponding fold width of 8, 10 and 12 mm (item 4), insert this edge into the bent edge of the first sheet (item 5) and bend the protruding part of the edge of the first sheet down, as shown in pos. 6. After this, the fold is compacted with a mallet.
f) Preparation of end transverse single and double standing and lying seams
The largest width of the end transverse fold is taken to be 9 mm when using steel weighing up to 5 kg/w 2; 11 mm - with steel weighing up to 6 kg/m2 and 13 mm - with steel weighing up to 8 kg/m2.
The end fold consists of a wide bent edge on one of the parts being joined and a narrow bent edge on the other.
A single fold is prepared as follows (Fig. 99).
Rice. 99. Preparing a single end fold manually
To fold the outer (larger) edge, a mark is made at a distance from the edge of the product of 15 mm with a fold width of 9 mm, 17 mm with a fold width of 11 mm and 20 mm with a fold width of 13 mm. Then the product is laid on a block, aligning the mark with its edge (Fig. 99, item 1), and with light blows of a hammer (narrow striker) begin flanging the edge of the product.
The flanging is carried out evenly along the entire length of the circumference, for which the product is constantly turned and gradually lowered down until the bead is bent at a right angle to the surface of the product (item 2).
After flanging, the bead is leveled with a wide hammer and a narrow edge with a width of 6, 7 and 8 mm is bent on it with a fold width of 9, 11 and 13 mm, respectively (items 3 and 4). This completes the preparation of the first part.
On the other part, the inner (smaller) edge is flanged with a width of 7, 8 and 10 mm, respectively, with a fold width of 9, 11 and 13 mm (item 5). Then insert this part into the first part and use a hammer on a block to connect both parts tightly, making a transverse standing seam (item 6).
To obtain a lying transverse seam, a standing seam is “filled” on a block (pos. 7) and compacted with a mallet. The fall should be dense, even, without gaps or tears. Inner surface connections should be smooth.
A double standing or lying flanged seam (Fig. 100) is prepared in the same way as a single seam.
Rice. 100. Preparing a double end fold manually
To flange the outer (larger) edge, draw a line at a distance from the edge of the part of 22, 26 and 34 mm, respectively, with a fold width of 9, 11 and 13 mm. The narrow edge on this edge is bent with a width of 7, 8 and 10 mm. On another part, the inner (smaller) edge is flanged with a width of 14, 17 and 22 mm, respectively, with a fold width of 9, 11 and 13 mm. Then the two parts are connected with a transverse single wide fold, as before stated above.
After this, using a hammer on the support (Fig. 100, item 1), this fold is bent and “filled up” (item 2), making a double standing seam to obtain a double lying seam; the resulting standing seam is “filled up” and compacted on a block (item 3) .
