You are here: 

Horizontal Directional Drilling Rig HDD Machine Classification and Application

There are many classification methods for horizontal directional drilling rigs. They can be divided according to the main working parameters of the equipment (maximum back-pulling force), the transportation mode of the main engine, and the structural form of the horizontal directional drilling rig.

  1. Classification according to main working parameters

The main construction parameters of horizontal directional drilling rigs(HDD machine)are: propulsion force/back-pull force, propulsion speed/back-pull speed, spindle speed, main Shaft torque, etc.  When classifying horizontal directional drilling rigs, they are mainly divided by back-to-back force, as shown in Table.

Drilling rig main working parameter classification table

HDD Drilling rig classificationMaximum back-pulling force (t) Features
mini HDD drill rig≤10Compact structure, mainly used for laying small municipal pipelines in cities
small HDD drilling rig10~40mainly used for laying short-distance municipal pipelines in cities
Medium HDD drilling rig40~120Used for laying larger diameter and longer distance pipelines in cities
Large HDD drilling rig120~400For main pipeline laying
Extra large HDD drilling rig>400 Used for the laying of national large trunk pipelines


ZLCONN mainly produce great HDD machine from 15T to 140T.  For telecom, our 22ton HDD machine, 28ton HDD machine, 35ton  HDD machine are widely used.

zlconn HDD machine Classification
zlconn HDD machine Classification

if you don’t know which to choose, please advise us some information of your project, we will help recommend.

1) What is OD diameter of the pipe? How many pipe you will pulling at the same time?

2) What is the material of the pipe? For example, HDPE, Steel,

3) What is the max distance from the entrance to the exit?  For example 150m, 200m.

4)  What is the soil condition?  For example almost soft soil or almost hard soil or a lot rocks or almost sandy?

  1. Divided by host transportation mode

According to the transportation mode of the main HDD rigs, it can be divided into crawler-type horizontal directional drilling rigs and tow-type horizontal directional drilling rigs.

  1. Classification by HDD drilling rig structure

Horizontal directional drilling rigs can be divided into integral horizontal directional drilling rigs and split horizontal directional drilling rigs according to different structural forms. Generally speaking, small and medium-sized horizontal directional drilling rigs are integral horizontal directional drilling rigs, and super-large tonnage horizontal directional drilling rigs are generally split-type horizontal directional drilling rigs.

Application scope

  1. Application fields

Horizontal directional drilling technology is currently one of the main technical means in the field of trenchless pipeline crossing construction. It is widely used in pipeline laying projects such as electricity, communications, natural gas, petroleum, and urban water supply and drainage. It is especially suitable for buried pipelines such as pressure pipelines. Projects with relatively low accuracy requirements. For gravity-type pipelines such as sewage pipes, due to the high requirements for pipeline burial accuracy, the applicability of horizontal directional drilling rig construction is low.

  1. Applicable working conditions

The purpose of trenchless construction is to lay pipes directly underground without digging the ground. It is usually a construction technology used when there are obstacles on the surface or underground that make it unsuitable to excavate and lay pipes.  At present, the obstacles that this technology is used to cross during pipeline construction mainly include rivers, highways, mountains, streets, and important or non-demolishable buildings.

  1. Applicable strata

The engineering risks of horizontal directional drilling are relatively high, mainly due to the impact of complex construction strata and unpredictable special underground environments on construction safety.  During construction, the construction stratum must be carefully selected to ensure construction safety.  Horizontal directional drilling is mainly suitable for stable and homogeneous strata such as silt, clay, dense fine sand, etc. It can also be used for stable Rock strata, but it is extremely difficult to construct in unstable strata such as gravel layers and backfill layers. See the sheet for details.

Applicable stratum

 stratigraphic conditionsapplicable Possible but difficult Extremely difficult
Soft soil and soft clay, silt and organic depositsl
Medium to hard clay and siltl
Hard clay and strongly weathered shalel
Very loose to loose sand layer (gravel content <30% by weight)l
Medium-tight sand layer (gravel content <30% weight ratio)l
Loose-dense sand and gravel layer (30%<gravel content<50% weight ratio)l
Loose and dense sand and gravel layer (50%<gravel content<85% weight ratio)l
Loose and dense pebble formationl
 Strata containing a large number of boulders, boulders or obstaclesl
 Weathered rock formation or strongly cemented formationl
 Weakly weathered-unweathered rock formationsl


Note: [Applicable] Directional drilling can be carried out in this formation using conventional construction methods.

[Feasible but difficult] On the basis of conventional construction methods, some necessary technical measures need to be taken to carry out directional drilling construction in this formation.

[Extremely difficult] This formation is not suitable for directional drilling construction.

Note: Refer to the classification of “Technical Regulations for Horizontal Directional Drilling”

Share This Story,Choose Your Platform!