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Trenchless pipelaying

Traditionally, underground communications are laid in a trench way. It’s necessary to dig out the upper fertile soil layer and green space. If the work is passing across the road, it’s also necessary to destroy the asphalt surface, thereby stopping the entire traffic flow until the works will be fully completed.  As a result, the cost of construction work is increased, and the execution time is extended    

Benefits of trenchless method

Trenchless laying of communications allows not only to avoid the destruction of the upper fertile soil layer, but also to reduce the consumption of material resources and the number of staff that is necessary to carry out the work. The nature is not damaged. 

In winter trenching is very difficult due to the freezing ground, while using a trenchless method helps to lay pipes easily. It’s possible to lay pipes below the freezing level of ground.

The work carried out in a small area, does not need the use of special equipment. The pipe is held under the road by a special cylinder. The cylindrical tip is attached to a rod, the length of which can be increased. The ground is removed by hand. A special technique is used on sites with a large amount of work.

Various ways of laying without trenching

Trenchless technology is quite versatile. Communications of any types, diameters, and wall thicknesses can be pull down by closed method.

Experts identify several ways for pipelaying

  • Sanitization.
  • Pipe-jacking or pipe-pushing.
  • Pipe ramming.
  • Horizontal directional drilling

How pipelines are being repaired

Sanitation of communications can be carried out in two ways.

  1. Sliplining
  2. Pipe Bursting.

During sliplining old pipe is keeping intact. After pre-cleaning the pipe hole from rubbish, workers place a new pipe with a smaller diameter inside the existing communications.  It looks like a “layer-cake”. New communication is protected by an old pipe. Even with a high level of wear, an additional layer of metal, concrete or ceramics would not come amiss for protection from damage and destruction.

Pipe Bursting includes the complete destruction of the old communications and laying new pipes on the already existing borehole. The debris is not extracted, but densely packed into the soil and used as a protection cover.

Pipe-jacking or pipe-pushing

Underground laying of pipes can be carried out by pipe-jacking method. Special equipment is used for making a special puncture in clay soils. The work is carrying out with help of special hydraulic jack, pipes movement speed is increasing due to a special vibration.

Pipe-pushing is a variant of the method for loose and pliable soils. A directed flow of water is used for the making a puncture. Special water well is washed with water.

Pipe ramming

It’s possible to use any pipes for ramming.but usually it’s used for laying big steel pipes. Special hydraulic jacks are mount on the cross-section.  You can force the pipe for a limited number of meters. Usually the total length of pipe ramming is not exceed 100 meters.

HDD method

The most effective trenchless method is horizontal directional drilling. It’s necessary to use HDD equipment for drilling. You can order a reliable horizontal directional drilling rigs from FORWARD.

HDD process divided into 3 parts:

  1. Pilot boring
  2. Backreaming
  3. Pipelaying

HDD machine equipped with special directed drill bit, which helps to make a pilot boring.  The navigation sonde is placed inside the drill bit.  

Before the beginning of the next step it’s necessary to exchange the drill bit to special reamer. The boring diameter is big, the backreaming process can be done several times sequentially increasing the size of the reamer.

In order to make pipelaying process more comfortable and easier, the diameter of drilling hole must be bigger than laying pipe. Drilling fluid is used to reduce friction in the horizontal channel.

HDD is a real way to save money

For high-quality drilling operations, it’s necessary to use high-class HDD equipment. You can order a reliable horizontal directional drilling rigs from FORWARD. All HDD machines are divided into 2 types:

  • Self-propelled HDD machines with a crawler.
  • Non-self-propelled HDD rigs. This type of machines are moving by crane.

Steel tracks cause damage to the road surface. In urban conditions it is convenient to use a track made of rubber or with rubber inserts (shoes).

If the HDD rig is purchased for operation in the cold season, then it is necessary to choose an appropriate equipment with the preheating system of engine and hydraulic oil. Then the problems of launching, even in the most severe frosts, can be leveled.


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