Pipes

How to crash into a water pipe under pressure: requirements and basic methods

July 27, 2020

Quite often the existing water supply system requires expansion in order to connect additional plumbing or create a new circuit. When cutting into a water pipe it is necessary to observe safety rules and strict sequence of stages. If there is no possibility of water blockage, then the insertion occurs under pressure.

It is possible to make insertion in a water supply system and without shutdown of the highway, but this requires special connectors and equipment

Approval and permission to carry out works

For, to crash into water pipes as without welding, and with its application, it is necessary to obtain all necessary permits and documents.

pay attention! Illegal insertion into the pipe entails administrative and material liability.

You first need to get a site plan to find out, whether there are any underground communications. This paper together with the title documents to the house, area) submitted to the water utility department. Obtained technical conditions for connection include:

  • place of connection;
  • diameter of the pipeline;
  • other data, depending on the purpose of the insert.

Then the data is submitted to the SES and the development and registration of design and estimate documentation is performed. Self-installation of meters and insertion into the pipe under pressure is strictly prohibited. To perform such work it is necessary to turn to specialists.

You should also remember, that the inset is prohibited bypassing the meters, in the main network of large diameter, which feeds the house, into the pipeline without a connection to the central sewer system, water supply of any diameters, if no permit has been obtained for any type of work.

Project development work, it is better to entrust preparation of materials and carrying out insertion to the corresponding service

The essence of the cutting process

Choice of method, how to crash into a water pipe, depends on its material. Modern systems are built on plastic, metal, metal-plastic and, less often, on cast iron pipes. For insertion it is necessary to receive openings. Of course, that when performing the process under pressure, water will come out of the pipe. Therefore special clamps are used for work, the design of which depends on the material of the pipes.

There are two most general rules, which must be performed when cutting:

  1. Equality of the inner diameter of the cut pipe and the diameter of the drill.
  2. The cut pipe should have a smaller diameter, than that, in which the hole is made.

The process of inserting into the pipeline depends on the type of water supply. The most common technologies are welding and the use of clamps. Clamps are needed in such cases, as cutting under pressure into a water pipe or in the absence of the possibility of cutting the highway. Works on highways with polyethylene pipes exclude the use of gas and electric welding.

When using welding, an additional coupling or thread is welded to the pipe, and on these connecting elements the root crane is put. The water supply must be turned off and the water drained.

Welding works are used only when connected to a metal pipe

Stages of insertion into the pipeline

The main tool, which will be needed for work - the special mechanism for drilling of water pipes under pressure. This method is quite productive and efficient, if you follow the rules of safety and follow all the technological stages.

First, the insulation is removed and the surface of the pipe is cleaned. Further, installation of a flange with output on a giving pipe is carried out and its fixing by means of a collar. To the latch, which joins the flange, the drilling mechanism is mounted.

pay attention! If the water supply is steel, then the installation of the drilling machine is not carried out on the clamp, and for welding the branch pipe.

After the welding process, the seam is checked for defects. If necessary, it can be boiled again.

Next, through the open latch, a cutter of the required diameter is inserted and a hole is cut. At the last stage, the drilling equipment is removed, blocking the water supply from the pipe, and insulation and anti-corrosion coating are restored. This sequence of steps is applicable to cast iron and metal pipes.

Drill a hole through the welded pipe with a special drill

Varieties of clamps

Collars come in different designs and configurations. The most popular are:

  • clip-clip;
  • saddle collar;
  • pre-drilling clamp;
  • electric welding yoke.

The use of a clamp-clamp is possible for insertion into the water main, which is not under pressure. Structurally, it consists of a pair of parts, and one of them has a threaded tap. The collar is clamped with bolts and can be made of plastic or metal.

For insertion under pressure into a metal pipe, asbestos cement or plastic saddle collar is used. It is attached to the pipeline with a bracket. Most often, this clamp is made of metal and has a locking plate or a special mechanism.

Drilling clamp serves for insertion into the pipe, under pressure. In addition to it there can be nozzles, as well as swivel connectors. For installation of a collar on steel, cast iron and plastic pipes require special equipment.

The design of the drilling clamp includes a rotary-shutter mechanism. Subsequently, it is used as a shut-off or control valve.

The clamp for insertion is chosen depending on purpose of assignment and material of a main pipe

The saddle collar is used for cutting into a plastic pipe. The design includes a cutter to obtain holes and a heating coil. The body of this clamp is made of special plastic and requires additional equipment for installation.

Cutting into the main pipeline

Withdrawal from the main pipeline under pressure is realized in 3 stages:

  1. Earthworks.
  2. Insertion process.
  3. Execution of drainage of water supply.

At the stage of earthworks the pit of the sizes is dug 1,5 X 1,5 meters. Its bottom falls half a meter below the pipe. You can dig first with an excavator (to metal or polymer tape, laid over the pipe at a distance 300-500 mm), then - with shovels. If the insertion point is in the well - this stage is excluded.

By means of an aperture in a nurse or a collapsible collar the body of armature is punctured. Such a connecting element is similar to a tee. A shut-off valve is screwed to the side outlet, which after the puncture blocks the flow of water.

For installation on plastic pipes it is possible to use ordinary saddle collars or nurses-clips.

pay attention! The best option for a nurse for polymer pipes - electric collapsible collar. Understanding on 2 parts, it is installed above the cut and soldered to the body of the pipe using a welding machine. This results in a high-strength and airtight connection.

Diversion of the water supply line from the highway is the final stage of the process. The beginning of the new pipeline is at the nurse's valve, and its end - on the water flow meter.

If you need to cut into the underground communications, then you first need to dig a hole in place, where the pipeline is located

Rules of well arrangement

To simplify the operation of the drain over the insertion site is a well (caisson). Its arrangement begins with the deepening of the pit on 50-70 div. Places of the selected soil are filled with a gravel pillow thick 20 div. Roofing material is rolled out on gravel and the concrete plate in thickness is filled in 10 cm, which is strengthened by lattices from armature.

To achieve concrete strength up to 70% necessary 3-4 days. After that, a mine of blocks is built over the slab. At the same time its neck rises to zero. The shape of the mine can be square or round.

A support plate with a round hole for the hatch is placed on the neck of the mine. At the final stage, the vertical insulation of the outer surface of the mine is arranged with the coating composition, and the pit is filled with selected soil.

Building a well requires a lot of time and money. For this reason, it is better to cut into the caisson of the water supply, than to perform diversion from the underground part of the highway.

At the point of connection to the water main, a well is arranged to access the connection

Insert into a metal water pipe

A saddle clamp is used for insertion into the metal pipe. There are several varieties. Before installing the appliance on the pipe, it is thoroughly cleaned of rust and dirt (if any). In addition to the lower part in the form of a semicircle, in the upper part of the clamp has a shut-off valve with a hole, designed for drilling and directly drilling. When placed on the pipe, the parts are fastened together with bolts.

pay attention! There are sealing rubber bands to ensure a tight fit to the surface of the water supply.

After fixing the clamp, the hole is drilled and closed with a cap using a special screw. Such a clamp can be used as a shut-off valve. You can also take a clamp with an already screwed valve. When the holes are ready, the drill is removed and the valve is closed. Then other necessary installation work is performed.

A special machine can be attached to the metal clamp, consisting of a ratchet handle, locking bolt, shaft with a drill bit at its end and a flushing tap. All elements are enclosed in a metal housing, which by means of sealing rubber bands fastens to a collar. Due to the presence of the guide clutch, can be drilled in a certain direction. This is how the insertion into a cast iron or metal pipe is performed.

Before carrying out works on insertion in a metal water supply system it is necessary to clear a pipe of a rust

Cutting into the cast iron pipeline

For, to drill a cast iron pipe under pressure, clamps are used, which have a special design and bimetallic crowns. The following points must be taken into account when performing the work:

  • brittle cast iron, therefore work should be carried out with light pressure;
  • before drilling the surface of the pipe is cleaned of the layer, which is applied to prevent corrosion;
  • unacceptable overheating of the crown;
  • work is carried out at low speeds.

After removing the compacted layer, a collapsible saddle is mounted on the insertion point. The contact point is sealed with rubber pads. The pipe is hardened with a carbide crown, which must be changed at least 3-4 times in the process of cutting.

The procedure for inserting into the cast iron pipe is as follows:

  • dig up the pipe, clean it from rust at the cut;
  • cut the top layer of hot cast iron with a Bulgarian knife;
  • to mount a folding saddle, to seal the joint between the valve and the clamp put a rubber seal;
  • attach the shut-off valve to the flange outlet, through which the crown will be inserted (tool);
  • drill a cast iron pipe, cooling the place of the cut;
  • remove the crown from the valve and block the flow of water.

It is also important to keep in mind the inclination of the nurse's pipe in the direction of the house 2 degrees.

Drills must be used to insert into the cast iron pipe, designed to work with metal

Insert into a plastic pipe

It is possible to crash into the plastic pipeline without pressure reduction on it by means of an electrowelded collar-nurse. It is made of special plastic and has a heating coil with a drilling mechanism. There is a bar code on the body of such a clamp, which allows you to enter the welding parameters with the required accuracy.

This method is used for pipelines with pressures up to 1,6 MPa.

pay attention! The saddle collar is resistant to corrosion and will last a very long time (to 50 years).

The pipe is pre-cleaned and bolted to it with a clamp, which has terminals for connecting a welding machine. The spiral is heated by a welding machine and the branch is welded.

Currently, a nurse with a built-in cutter and valve is often used. A coupling is used for this purpose, to make a plumbing insert by welding. About through 1 an hour after complete cooling the milling hole is made screws and shut-off valve.

Welding installation of a branch pipe to a water supply system from steel should be carried out only by professionals. Installation of pipelines on the pig-iron or polymeric pipeline can be executed independently, but the water supply must be disconnected. Pressure insertion work must be carried out in compliance with all rules and recommendations, otherwise such work may be dangerous.