Laying pipe jacking: technological rules

If underground communications cross a road track or tracks, the dismantling of such objects can be extremely difficult and often even impossible. Will help solve the problem of laying pipe jacking. This method is much easier and cheaper to implement.

Those who wish to learn how to lay pipes in the ground without disturbing the ground cover, demolition of buildings, movement of mobile objects, we reveal the specifics of the technology. Here you will learn what equipment is used in the course of the work, in what way are made punctures.

In addition to the title technique we describe alternatives laying pipes in the ground by trenchless technology, we have made the scheme, photo collections, and video materials.

What is the method of puncture?

The method is called puncture technique in which a hole can be obtained without developing and excavation by its seal.

This method is suitable for the construction of steel structures. Diameter can range 100-500 mm, hole length - 30-50 m Puncture under way -. Is one of the most popular methods for the trenchless laying of communications.

Thus satisfied underground branch water, sewage, is fed to the site from the gas.

Managed puncture is used for laying:

• Communications of metal and plastic;
• casings, which are then placed in a gas and water pipes;
• cases for the power and telephone cables, etc.

Puncture is not only used in cases where you need to safely cross the road or railroad tracks.

The method is suitable for the construction of holes into the well (assuming that the diameter of the well for at least a half meters), basement of the house, to hold wires under some relatively small object, if necessary, etc.

Most often controlled puncture is performed in the thickness of the clay soil under various roads, for example, a highway or railroad tracks. For this purpose the jack-pressure pump unit, for example, such as setting Ditch Witch P80.

Additionally, you will need a set of dilators, rods, heads and other tools, through which drilling is performed.

Required use hydraulic station. The necessary force effect provides a hydraulic cylinder, an acceptable power unit is about 36 tons. The work station should provide an internal combustion engine. To monitor the progress of works in soil column used wireless connections locations.

As an example, consider a radar apparatus operating procedure Eclipse. The drill head is placed a probe that transmits information about the course of drilling operations.

Information supplied to the locator. There the data is analyzed, whereby the determined current location of the drilling tool a lot thicker angle drilling head, its movement matching previously made plan works. At the same time the state is controlled by the probe batteries, which come with information.

The drill head is arranged in such a way that part of its surface is bevelled. This improves performance, but is reflected in the quality of work.

Because of the skew in moving deep in the ground position of the head will be continuously deflected from the vector effects. The operator must constantly adjust the trajectory of movement of the head, checking the results of the location.

That tool is moved in a straight line, it is necessary to rotate at a constant speed. The first step of performing a puncture begin in the starting pit and finish - in the receiver. Here, instead of the drilling head is fixed on the installation tapered dilator.

This device passes horizontal hole formed in the opposite direction, allowing it to expand and seal the walls.

Thereafter, the resulting pipe is inserted into the long hole of the required diameter or case for lining of communications. Depending on the situation can be laid not one but several pipes. Further action is to pave the communication and connect to the overall system.

During the preparatory work is also necessary to consider the storage location of pipes that need to be close to the venue for the drilling.

Usually ground for the pipes include next to the starting excavation. The dimensions of the site for storage depend on the length of the pipe, which can be up to six meters. It is desirable that selected for laying pipes They were stored in a horizontal position. This will simplify the installation and reduce the likelihood of structural damage.

In addition, the need to provide access roads to the starting trench to seamlessly deliver the necessary materials and equipment for work.

First the pre-site survey of the work on the ground. Specialists in this case use the project documentation, based on which, as well as the object of analysis results compiled execution plan puncture.

If you need to puncture a subject experiencing severe traffic loads (tram lines, highway, railway, subway, etc.), the pipe is laid in a special case.

Such a case should have a diameter greater than the pipe dimensions of about 15-20 cm. First lay a case, then it is mounted in the pipe, and the space between these communications is filled with a solution which can be used for inexpensive Cement M-100. Enclosures reduce the load on the underground utilities and reduce the risk of damage.

Hydro, vibroprokol and punching

Distinguish hydro and vibroprokoly. In the first case using a water jet under high pressure which has a special tip of a tool for forcing the soil.

This method is particularly effective in non-cohesive sandy soils, easily eroded under the impact of the jet. It allows to make a hole diameter of about 50 cm in the minimum amount of time. But the maximum length of the borehole at gidroprokole - 30 m.

Vibroprokol, as the name implies, it is performed with the aid of exposure. The device used to perform puncture impact-vibration-pinch installation pathogens longitudinally directed vibrations.

Static indentation combined with the impact on the ground shock pulses vibromolota. The method is applied on saturated and malovlazhnyh sandy soils for laying pipes, and for extracting them. Hole diameter can be 50 cm, and its length - 60 m.

punching method by using jacks as puncture. But in this case, the pipe is sent into the ground an open end. In advancing structure forms a dense plug of soil into the tube, which is then removed.

To perform this type of operation using two to eight thick (200-400 tons) of hydraulic jacks, which are required for assembling with the frame abutment wall and headband.

For change such a device may take up to 10 meters of soil, and the total length of the wellbore is typically less than 80 meters. If you want to build a longer track, it is divided into individual sections of not more than 80 meters.

This method also requires a primary device and a finishing pit, in which is set and necessary hydraulics.

Driving of each portion is performed twice: in the forward and then reverse direction. Control of the mechanisms and the quality of punching is the operator who is in the pit.

Technically, this method is more complicated than a normal piercing, but it can be used on almost any terrain. design diameter can reach 172 cm. The sample core, formed inside the pipe, can be done manually or by mechanized means.

Advantages of puncture

Demand method puncture due to its significant advantages compared to other embodiments of this type of work. For example, a puncture is available at any time of the year, high or low temperature outdoor air and soil a large irrelevant.

installation work does not require the use of bentonite slurry, feeding water into the wellbore or drilling fluid. It is a compact and powerful unit, which is equipped with a reliable electrical system. It is not difficult to deliver to the object and install. In this compact dimensions do not interfere with the device to operate with high power.

Turnaround time is also less than with other methods. Even if the area where the puncture is performed, there is an increased level of groundwater, there is no need to carry out activities on abstraction of water from the site.

During the passage of the expansion cone is made and seal the walls of the trench, so additional work in this regard is required.

Performing puncture on different objects

The complexity and speed of this type depends on the conditions, ie, on location and characteristics of the object under which the puncture. For drilling under rail tracks usually require serious enough clearance. First you need to agree with the drilling of a number of railway services.

In Russia, you need to apply to the EV units CC, SRC NODG, inverter and other services of JSC "Russian Railways". It is mandatory to draw up a contract to conduct technical inspection, as well as the installation of safety net packages. All executive documentation shall be coordinated and provided the railway authorities.

In the distance the way documents transferred at the end of a cycle of works on laying pipes. In the cities, a puncture under the road in great demand during the laying of new communications, especially in places with historical sights.

The method makes it possible not only to maintain normal road traffic, but also to prevent the destruction of the old bridge, when it is necessary to lay pipes under such sites.

The restoration of this object can be difficult, and sometimes impossible. In a cottage village laying communications method of puncture allows you to perform all the work with minimal damage already finished objects: roads, fences, etc.

Evaluation of alternatives

In addition to the method of controlled puncture, there are other options device communications in soil column devices without trenches. Sometimes an alternative may be more acceptable than a puncture, it all depends on the specific situation.

Horizontal Directional Drilling, Also known as directional and used for the construction of pressure and pressure pipelines. Drilling is carried out in this way from the ground. The diameter of the hole should take 30-50% more than the size of the pipes, which are supposed to put into it.

Hole expanding at once, but in several stages. When this solution is used bentonite, which is mixed with the loosened soil and facilitates its removal from the barrel. Additionally, this working fluid is used to cool the drilling tool and further it forms on the walls of the mine layer which protects them from damage.

For pumping waste bentonite slurry used cesspool emptier. After evacuation of waste solution must take in a landfill for disposal. If work is carried out correctly, the result is a clean well with solid walls.

Rigs for performing work of this type have various characteristics such as the torque and pulling force. It depends on this length of pipe to be laid in the soil column, which can be up to 1000 meters.

The allowable diameter of the tubes - 120 cm. By horizontal directional drilling can be stacked and metal and plastic tubes.

Drilling is performed by a pre-calculated trajectory drilling tool movement is controlled by means of locating systems. Collaring angle can vary within 26-34 degrees.

Another important factor when using HDD - flexural rods, which may be 6-12%, depending on their type. Another popular method of trenchless pipe laying - auger drilling. For its implementation using dedicated hydraulic unit acting as a jack.

First make the start and finish pits. The depth of each of them should be one meter deeper than the level of laying the pipeline. The starting pit lowered hydraulic installation, which rotates the screw and pipe jacking. As a result, part of the soil is removed and the obtained well pipe.

Then mounted inside the pipe, cases, etc. Maximum length of the gasket is typically only 100 meters away, but Communications diameter can reach 172 cm, largely depend on the parameters of soil type on which is carried drilling.

To control the conduct of work during auger drilling using a laser that It provides the correct angle drill, and also track the drilling direction with a high accuracy. After the screw reaches the finishing pit, it is withdrawn from the well resulting in reverse order.

microtunnelling - a highly accurate method for trenchless laying of communications, which is executed by a special tunnel shield.

To move the device uses a high power jacking station. It has an impact on a column of w / w of pipes which are attached to the shield. Gradually the length of the borehole is incremented, so the column length is increased by building concrete structures.

This method also requires the preliminary preparation of two pits, the distance between them can vary within 50-500 meters. Jacking installation should be dipped into the starting pit to a depth that corresponds to the lining of communications. If the well is longer than 200 meters, typically use an intermediate jacking station.

Tunneling shield loosens the soil, which is washed with water or bentonite slurry coming from the supply lines. Waste liquid, mixed with particles of soil moved into the sump of the vent lines. After tunneling shield gets to finish the excavation work can be considered completed.

Equipment dismantled and removed. microtunnelling method can be installed not only reinforced concrete, but steel tubes. To control the correctness of the work using a navigation system consisting of a laser, and a target measuring wheel.

For long sections (200 m) is considered to be an efficient electronic laser system equipped with hydrostatic level which gives precise information about the depth of laying the pipe, regardless of the air temperature inside design.

Selecting a suitable method subtleties

Method laying communications via horizontal drilling has selected at the design stage of a particular process. If trenchless pipe-laying will be performed as part of the construction of a facility, such as an apartment house, the work can become part of the overall construction project.

When designing take into account the following information:

• Communications length which is necessary to lay trenchless;
• diameter pipe or sheath;
• the material from which the communication;
• the depth to which the tube must be laid;
• pipeline type (pressure or pressureless);
• possibility to mount the starting and finishing pits suitable depth;
• the access roads to the place of work;
• the availability of sufficiently large areas for the storage of materials, equipment, etc .;
• proleganiya level of groundwater;
• other geological features of the site;
• layout is already available in the communications area.

Under construction is sometimes necessary to change the already compiled project. This can be caused by the desire to reduce costs by using, for example, plastic pipes instead of steel. In addition, the location of underground utilities plan for the site is not always accurate enough.

When carrying out such may show unrecorded pipes or cables. All these factors may require changes to the project, but it can also affect the decision on the drilling method.

If the depth of laying communications is low, there is a risk of the upper layer of soil subsidence, particularly if used in drilling bentonite solution. In such cases it is better to give preference to the horizontal auger drilling.

Very often the drilling method is determined by what kind of equipment is available to the organization, to carry out orders.

For example, if the builders have jacks or of horizontal directional drilling, then he will be given preference over jacking. Most of these changes are dictated by considerations of economic benefits.

Conclusions and useful videos on the topic

Clearly the process of the plant managed to perform puncture presented in the video:

Managed puncture - a highly accurate and relatively inexpensive way to pave the way for communication or other object. At the same time it is important to design all the work and observe the technology accurately.

Do you want to tell about the interesting facts related to the laying of pipes for puncture technology? There were questions in the process of familiarization with the information provided? Please write comments in the text box below the article.