What Is In-Situ Machining?

In-situ machining, also known as on-site machining, field machining, or portable machining, is the process of carrying out precision machining operations directly on installed or fixed equipment — without the need to dismantle or transport components to a workshop.

Instead of removing large or critical assets, specialised portable machine tools are brought to site, allowing machining work to be completed accurately, safely, and efficiently in the equipment’s operational location.

In-situ machining is widely used across industries where downtime is costly or component removal is impractical, including marine, oil and gas, power generation, nuclear, steel, and heavy industry.

How Does In-Situ Machining Work?

In-situ machining uses purpose-built, portable equipment that can be mounted directly onto the component being repaired. Common techniques include:

• Flange facing – restoring damaged or corroded flange faces

• Line boring – repairing worn or misaligned bores

• Pipe cutting and pipe preparation – preparing pipework for welding

• Shaft machining – repairing journals, keyways, and bearing areas

These machines are aligned and operated by skilled on-site machinists, achieving tolerances comparable to conventional machine shops.

When Is In-Situ Machining Used?

On-site machining is typically chosen when:

• Components are too large or heavy to remove

• Dismantling would cause extended downtime

• Removal would require major disassembly

• Equipment is located in remote or offshore environments

• Repairs are needed during planned shutdowns or outages

In many cases, in-situ machining can reduce downtime from weeks to days — or even hours.

Benefits of In-Situ Machining

The key advantages of on-site machining include:

• Reduced downtime – no transport or reinstallation delays

• Lower costs – avoids cranes, logistics, and disassembly

• Improved safety – fewer heavy lifts and movements

• Precision repairs – carried out by specialist machinists

• Extended asset life – restores components to specification

For critical assets, these benefits can translate into significant operational and financial savings.

Reekie Machining’s In-Situ Machining Expertise

With roots dating back to 1946, Reekie Machining is one of the pioneers of modern in-situ machining. The company has been developing and delivering on-site machining services for decades, supporting clients across the globe.

Reekie Machining specialises in:

• Flange facing services

• Line boring services

• Pipe cutting and preparation

• Complex on-site machining repairs

By combining specialist equipment with highly experienced machinists, Reekie Machining delivers precision repairs in the most demanding industrial environments.