When gas welding edge of the pipe is heated to melt the flame.The same flame melted filler half so that its liquid metal fills the gap between the welded pipe ends.The result is a weld bead.
Acetylene - a gas that burns in a stream of oxygen and during its combustion develops temperature 3000 ° C. Oxygen itself does not burn, it only supports combustion.
Acetylene obtained from calcium carbide in special equipment - generators.Oxygen for welding arrives in steel cylinders, where it is under high pressure up to 150 atm.Directly for welding high-pressure oxygen is not required, so the pressure is reduced by the reduction gear, joins the cylinder.
Gas welding tool: a - Burner;b - Cutter;in - kerosinorez K-51
gazosvarshchika main tools - the burner and torch.Burner (Fig. A) has two nipples for accession by the rubber hose from the oxygen tank and the same hose from the gas generator or the acetylene cylinder.
In the body of the burner are two channels on which the oxygen and acetyl
Gas cutting torches made.SUMMARY gas cutting process consists in the fact that the metal is heated to a temperature at which it is combusted in a stream of oxygen supplied from the cylinder.Cutter (Fig. B) is different from the presence of the torch from him 1 additional handset with a crane 2 for oxygen supply to the place of cutting.
When oxygen cutting of metals can be substituted acetylene with kerosene.Apparatus for cutting using kerosene consists of a welded tank capacity of 5 liters in which kerosene is pressurized to 3 atm kerosinoreza hose kerosene and oxygen from the oxygen cylinder.
Fig.kerosinorez shows K-51, designed for straight and shape cutting for steel up to 200 mm.
Electric welding is based on the heat of an electric arc.When electric welding one wire from the welding transformer is connected to the welded object, the other - to the electrode, clamped in a special holder.Approaching the electrode to the welded seam, ignite the arc.The heat of the arc melt the base metal, welding wire and flux, which daubed electrode.Electrode coating performs the following functions: welding arc stabilizes and protects the molten weld metal from exposure to oxygen.Electric welding profitable gas, as it does not require gas.
When gas and electric welding of pipes between them leave for the formation of the joint gap of 23 mm;welded ends purified by rust, scale, oil, paint.At the ends of pipes with a wall thickness greater than 4 mm chamfer.In any method, and a welding should not be formed on the inner surface of pipes sagging.To this end, butt welding of pipes with diameter of 1 / 2-1 inches often used Couplers of larger diameter pipes.
Pipe welding using Couplers
resorting to flexible pipes for smooth turns in the pipeline.
When installing piping bent elbows have a number of advantages over the squares.They all prezh de represent less resistance to the passage of the coolant, which is essential for hot water heating systems with natural circulation.In addition, the outlets can be bent at any angle.Finally, the use of elbows and other curved parts makes it possible to reduce the number of threads.
most common types of bending in the pipes - it bends, duck, braces and rolls (see. Fig.).Pipe bending
1/2 and 3/4 inches is made on manual machine Volnov structure which consists of a hub 1 for attaching the plate 2 on the machine bench, a fixed roller 7 with the yoke 3 and the movable bracket 4 with roller 5 and the handle 6.
and - removal;b - Duck;in - bracket
to bend the pipe at the machine, it is inserted between the rollers so that the end of it went into the bracket.Then, holding the handle, turn bracket with movable roller around a fixed axis of the pipe until the required bending.To increase efforts to handle the bending machine can be extended pipe segment.
for bending large diameter pipes used electromechanical machines.
1 - hub;2 - plate;3 - fixed roller;4 - bracket;5 - movable roller;6 - the handle;7 - a collar
Cutting pipes - one of the basic operations when performing assembly work.Typically, the cutting is performed mechanically by means of a special roller and compound machines or machine tools, general purpose - driven saws, machines with abrasive discs (Bulgarian), and so on. D.
for cutting tubes manually apply hacksaw and cutters.
reciprocating machine is a sliding frame, match in front of a tension screw, having lamb and back - with a tail rod.The reciprocating saws with a screw and rod mounted saw blade.The machine can push at different lengths to the length of the saw blade.For this purpose it is provided with a holder in its frame made cutouts.The mobile part of the frame is fixed in a holder and secured to the front of the frame with screws.
Hand hacksaw machine with a detachable clip
The figure shows the sliding hacksaw another construction, which clip directly connected to the handle of the saw machine.The shape and position of the handle for more convenient operation.
Hand hacksaw machine with a holder attached to the handle of the machine
for fixing the saw blade machine available in the tension screw and a tail rod slots and holes corresponding to the holes in the saw blade.The cloth is inserted into the slot so that the teeth are directed forward, and the end holes aligned with the holes in the tension screw and a tail core.In the matching holes give birth to the pins and pulled tight lamb.Interference should not be excessive, otherwise it may break the web, but should not be weak, since then the web will bend during operation and eventually break.
When cutting pipe Hacksaw tube secured in a vise or prizhime.s condition that the cut line located as close as possible to the sheet clamping.
reciprocating machine keep the left hand on the frame and the right by its handle.Pressure on the web only with a working course, ie. E. When the course ahead.During operation, you must ensure that all involved in the cutting saw blade and it does not overheat.
more productive than when using manual hacksaw, pipe cutting roller pipe cutter.The figure shows three roller pipe cutter for pipes up to 2 inches.It consists of a housing 1, 2 mobile holder, clamping screws 3 and cutting rollers 4.
three roller cutter:
1 - the case;2 - the mobile holder;3 - clamping screw;4 - cutting rollers
Technology of work:
- oiled machine oil cut place on a pipe clamped in the nip, left hand fed cutter to the pipe bottom, right-hand rotating clamp!ensuring that rollers slightly ran into a pipe;
- when this is achieved, producing a pipe cutter rocking motion up and down and at the same time more and more pull together rollers rotation handle clamping screw cutter;
- after a while the pipe is in the intersected in the intended place.Toupee end of the pipe when it is necessary to hold the hand;
- external burrs formed on the section of the pipe when cutting roller pipe cutter, remove a file.
filing called surface treatment of metal parts (pipe) with a file in order to obtain a predetermined shape, size designation and the desired surface finish.
Files - cutting tool.The cutting action produces grooved teeth on its surface, is removed from the treated metal chips in the form of sawdust.There
Files semicircular rectangular, square, triangular, round knurled different sizes.Such a variety of forms of files allows you to successfully file the external and internal surfaces of different configurations.
The magnitude of notches Files are drachёvye, personal and velvet.
Files are made of tool steel and necessarily pass thermal processing.
They come in different lengths.On the tail of a file handle is pushed strongly.
and pipes saw round Details clamped in a vise or nip.
and - types of incisions (I - bastard, II - personal, III - a fine file);b-form of a file (1 - flat 2 - semi-circular 3 - square, 4 - triangular, 5 - round)