Trenchless Pipe Installation: A Complete Guide for Beginners

Trenchless pipe installation has slowly become the go-to of the construction industry as the BEST METHOD for laying pipes in place, whether residential, commercial, or industrial.

But why is it getting all this traction and credibility?

In this article, we will explore exactly what it is, its different applications, and its many advantages over its traditional counterpart.

If you're keen on checking out this information and looking through some solutions for your current project, keep reading!

What Is Trenchless Pipe Installation?

A pipeline installation using the traditional method requires open trench excavation, pipeline transport, and coverup of the installation. This method is expensive and disruptive to many.

With trenchless technology, you can install pipelines in an ECONOMIC and DISRUPTION-REDUCING way.

There's no need for an open trench. Only a launch pit and receiving pit are typically necessary because many of these techniques can excavate as they install.

This particular project is effective for the installation of sewer lines or utility lines, for example, where the process of digging might be too difficult. You can also use trenchless methods for overall sewer repairs.

The Different Types of Trenchless Pipe Installation

You can use several trenchless methods in pipe installation. Distinct ways are employed depending on the pipe type and size, location, soil type, and other important factors.

Horizontal Directional Drilling (HDD)

Horizontal directional drilling involves using a drill to form a borehole for small to large-diameter pipelines. It typically employs three phases with drilling and the use of a reamer.

In the first stage of horizontal directional drilling (HDD), the drill rod has to be angled correctly. A drilling fluid is used to facilitate the drilling process.

Reaming is done to ENLARGE the hole and back reaming the required pipe. Finally, the pipe is pulled back.

Horizontal directional drilling is a trenchless pipeline installation method for underground applications. A sewer pipe, for example, can be installed without causing traffic.

Pros

• Can bypass obstacles deep underground
• Can cross wetlands

Cons

• Not great for large grain content soil conditions
• Requires highly skilled professionals

Horizontal Auger Boring (HAB)

The horizontal auger boring method needs two pits: a launch and a reception shaft. It also requires a casing pipe system with a cutting head and rotating augers jacked into a pilot hole.

The attached cutting head and rotating auger remove soil as it is excavated. These are to be attached to each new casing.

The casing pipe system it lays down should be continuous. A casing is affixed one after the other horizontally. Sets of the casing should be set until the pipes reach the surface.

This process is typically done for small-diameter pipelines (1.2m). It's also possible to use a steel pipe in this method.

Pros

• Install and excavate at the same time
• Effective for many soil types (except boulders and mixed soils)

Cons

• May need different sizes of casing, cutting heads, and augers

Pipe Bursting

Pipe bursting is a method of replacing existing pipelines with new ones. The process works by FRACTURING the inner diameter of the existing pipeline by pulling the new pipe into its place.

A pipe bursting tool, a cone-shaped head attached to the new HDPE pipe, is pulled or pushed into the host pipe by a machine.

This old pipe then shatters, and the length of a new pipeline is smoothly laid in its previous location into a successful installation.

Pipe bursting works great when an existing pipe is aging and due for a substitute.

Pros

• Quick and efficient trenchless pipe installation method
• It can be used with different pipes and materials

Cons

• If the existing pipe has already burst, this is not an eligible fix

Pipe Jacking

Pipe jacking is one of the MOST USED trenchless methods to install a new pipe. In this process, the pipeline to be installed is divided into shorter lengths pushed by a rig.

At the starting point of the pipeline installation, small excavations are dug into the ground to fit the jacking rig, which pushes these smaller pipes into the pilot hole until it reaches the exit.

With the sequence coming up to the exit, the jacking rig pushes further until the cutter head reaches the pit.

Pipe jacking is often confused or used interchangeably with pipe ramming (which we will discuss below), but these are DIFFERENT pipe installation methods.

Pros

• Compatible with different types of soil
• Avoids traffic and massive excavations

Cons

• Casing orientation can only be straight

Slip-Lining

Slip-lining is an umbrella term for methods in which you: a) install a carrier pipe into the host pipe or b) use continuous pipes in a line. It is mainly used in water and sewer pipelines.

Typically, it is used to refer to the former. The new pipe is either PUSHED or PULLED into the host pipe, and the old one is grouted. This method seals leaks in old pipes (usually straight).

It starts by cleaning out the host pipe. Then, a liner is cut to size. It's coated with thermal epoxy or resin and inserted, and compressed air will form it into the shape of the host pipe.

It will cure and harden, and the lining will be pulled out of the original casing. The cured material essentially grouts the original pipe.

Pros

• Sturdy and long-lasting
• Economical and minimizes destruction

Cons

• Limited to reinforcing straight pipes

Close-Fit

This pipeline rehabilitation method is similar to the one discussed in slip-lining, except the lining itself is attached to the original pipes instead of being a vehicle for another substance.

For this to be properly installed, the inner casing (which is currently "deflated") must be pulled into the older pipe and come out of the other end.

At such a point, it will be inflated to its intended diameter, effectively taking the shape of the original pipe, and it should stay in that form.

This pipe installation is VERSATILE, catering to pipes with diameters ranging from the smallest to the biggest lining.

Pros

• Original pipe capacity is not hugely affected
• Can accommodate various diameter and length needs

Cons

• A pipe with bends is difficult to address

Micro-Tunneling

This installation method uses a remote-guided boring machine that also jacks pipes into a straight line, though it has successfully navigated vertical directions as well.

It's an advanced process that we view as somewhat like combined methods. It has the AUTOMATED EXCAVATION features of HDD/HAB and the installation function of pipe jacking.

Thanks to its guidance system, this method is usually used to install a pipeline very deep underground when digging open soil is impossible.

Still, the project must be studied well, and the operator must be HIGHLY SKILLED. If the cutter head wears out in the middle of the excavation, an emergency shaft needs to be constructed.

Pros

• Least disruptive among other methods
• Technology increased operation efficiency

Cons

• Cutter heads can wear out if the operator is not careful

Pipe Ramming

As mentioned earlier, pipe ramming is often confused with pipe jacking because they both use a pushing motion to complete the installation of a line of new pipe.

However, the process of pipe ramming involves the use of a percussive hammer rather than hydraulics used to jack a pipe in the other methods.

When the hammer causes the pipe to advance, it COLLECTS the spoil inside, which will be cleared when the pipe is fully in its place.

This technique is safe and has been used for years, and is particularly useful for areas where the goal is to minimize causing as much damage as possible.

Pros

• Great for places where you expect ground loss
• Ideal for railroads, landscapes, etc.

Cons

• Installation can lack precision

The Benefits of Trenchless Pipe Installation

All these methods for trenchless construction have a common denominator: they offer a better solution than the old ways of doing trench work.

Here's a full list of their advantages:

#1 Durable

The methods discussed earlier are quite modern and were mostly developed to SUPPLEMENT and IMPROVE the pipe systems from before.

This is a major advantage because these installation techniques are built to last longer and require less maintenance than the older ones.

#2 Convenient

As civil engineering advanced, so did our installation methods. The trenchless technologies enable us to upgrade them to cause the least inconvenience.

You could be driving through traffic and wouldn't even know that a pipe is being installed underneath because the method is quite discreet.

#3 Safer Than Traditional Methods

By not needing to make deep digs through the surface, we're able to AVOID life-threatening incidents both on the workers' end and the civilians'.

Since the excavation sites are isolated and most of the work happens underground, the threats are isolated and minimized.

#4 Less Disruption to Environmentally-Sensitive Areas

Minimal disruption to the environment greatly helps communities stay safe and in place, even through pipe system upgrades or the installation of new establishments.

For areas that are already at risk, a decline can be furthered by open excavations.

#5 Preserves Ground Above

Depending on a place's soil type, a pipe installation method could be suitable or disastrous. Because these techniques are well-researched, the surface can stay safe.

Underground installation also ensures that the aesthetic of the place remains intact.

This is especially useful for areas that tend to get traffic jams. By reducing the amount of space needed for the work, any holdups and delays are also minimized.

#6 More Affordable

An open excavation requires expensive equipment and more labor and time. Going trenchless is COST-EFFECTIVE because it can eliminate or minimize some pricey factors.

Not to mention, it makes other development possibilities an achievable reality! Hence, we suggest going for a trenchless method, may it be for sewers, water lines, ductile iron pipe installation, and other related construction projects.

Frequently Asked Questions (FAQs)

Here are answers to some commonly asked questions about trenchless pipe installation:

What Are the Most Common Trenchless Methods and Operations Used?

The two most common are probably pipe bursting and pipe jacking (not pipe ramming), which are for rehabilitation and initial installment.

Pipe bursting and jacking are less labor intensive, require relatively more affordable equipment, and produce great yields.

Is Trenchless Pipe Installation Worth It?

If you choose the correct trenchless method for your project, it should be more cost-effective and time-efficient than traditional trench work.

These techniques have only been gaining more and more popularity and credibility in professional construction leagues through the years.

Conclusion

Trenchless pipe installation has genuinely been a better alternative to the traditional open excavation of trenches. They offer so many advantages, and there are so many options!

Its approach allows a more ECONOMIC and ENVIRONMENT-FRIENDLY approach, not just for effectively piping new establishments, but for upgrading the aging ones already there.

If you need a refresher on all the techniques and information on why they would or would not be the perfect solution for you, feel free to check back on this article!