Shrink fitting is a reliable method for joining two metal components by using extreme temperatures to create a secure interference fit. When a interference fit is needed, this method avoids flame, adhesives, and mechanical fasteners – making it ideal for sensitive or high-performance environments. Whether you work in aerospace, manufacturing, or building services, understanding this process can reduce costs, save time, and eliminate unnecessary system downtime. Discover ‘What is Shrink Fitting’ below:
What is Shrink Fitting? How This Precision Engineering Method Works
This mechanical process changes the size of metal components by altering their temperature.
Engineers typically follow one of two approaches:
- Cold shrink method – Engineers cool the inner component with liquid nitrogen, causing it to contract. They then insert it into the outer part. As the part returns to room temperature, it expands and locks tightly in place.
- Heat shrink method – Technicians heat the outer component to make it expand. They insert the inner part, then allow the outer piece to cool and contract around it, forming a secure seal.
The method chosen depends on material properties, size tolerances, and safety considerations.
Why Cold Shrink Method is More Commonly Used:
- Engineers cool the inner part because it’s smaller and easier to handle
- Cold shrink gives better control over fit
- Heating large outer parts can cause distortion or damage
- Liquid nitrogen cools parts quickly and leaves no mess
- This method avoids oxidation and preserves material strength
- It’s faster, safer, and more precise for tight assemblies
Here’s how the cold shrink method process works in practice:
- The cool components like nozzles or bushings down to cryogenic temperatures
- Then the rapid cooling causes the metal to shrink
- Next the shrunken part is inserted into its corresponding housing or valve
- As the metal warms up, it expands and creates a tight, pressure-resistant fit
Why Use Shrink Fitting Instead of Welding or Adhesives?
This method offers major benefits:
- No heat damage – Ideal for delicate systems and fire-sensitive areas
- Stronger joints – Handles vibration and pressure more effectively
- Clean process – No chemicals, sparks, or open flames
- Removable – Can be reversed without damaging the parts
For example, in our Croydon shrink fitting project, our team used liquid nitrogen to install replacement components in a high-value assembly. The task was completed with zero downtime and no dismantling of the wider system.
Applications of Shrink Fitting in London
This technique supports a wide range of industries – from local commercial systems to high-value transport infrastructure. Typical applications include:
- Aerospace component installation
- HVAC plant assembly and repair
- Valve and pump housing installation
- Transport and rail system maintenance
- Plantroom upgrades and retrofits
In one recent project, shrink fitting was paired with aircraft maintenance to allow a live valve swap at an aircraft maintenance facility. The result? No disruption, and a fast, efficient install.
The Benefits of Liquid Nitrogen Shrink Fitting
Choosing the right partner for shrink fitting in London comes down to skill, safety, and control. At IDWe Pipe Freezers, we use liquid nitrogen to deliver maximum precision with minimum risk. The benefits include:
- Rapid cooling to shrink components in minutes
- No flame or heat, ideal for sensitive environments
- Mobile setup, allowing us to work on-site across London and the South East
- Expert engineers who plan, monitor, and execute with care
We’ve delivered shrink fitting services for critical sites, including commercial buildings, industrial facilities, and transport infrastructure. Every job is risk-assessed and handled by qualified engineers who understand the tolerances and specifications required.
Safety First, Every Time
Shrink fitting with liquid nitrogen must be handled with care. We follow strict protocols for temperature control, PPE, ventilation, and containment. We also work closely with facilities teams to ensure the site remains operational and safe during the procedure.
You can read more about our full range of services, including pipe freezing and shrink fitting, on our services page.
Why Choose Shrink Fitting Over Traditional Methods?
Shrink fitting offers several advantages over conventional joining techniques:
- No heat damage: Ideal for precision components and sensitive environments.
- Permanent and secure: Produces a strong mechanical bond under pressure and temperature variation.
- Minimal downtime: Faster than traditional methods, with no system-wide shutdowns required.
- Clean and safe: No cutting, fire risk, or hot work permits needed.
Our engineers specialise in shrink fitting using precise, controlled liquid nitrogen applications. We ensure accuracy and safety on every job.
Shrink Fitting Company
Can we help you?
For safe, effective shrink fitting and pipe freezing services in London and the South East, trust our experienced professionals to deliver high-performance solutions. Talk to us today!
As a leading Pipe Freezing Company we deliver Shrink Fitting non-intrusive pipe isolation with precision and reliability. The team also provide services across London, Kent, Surrey, Hampshire, Essex, East Sussex, West Sussex and beyond.
Contact us today for:
- Shrink Fitting
- Liquid Nitrogen Pipe Freezing
- Valve Replacement Solutions
- Hot Tapping Services
- Pipe Welding Services
Get a quote:
Talk to us about your project today, please call 020 8302 7644 or email info@idwe.co.uk
We can adapt our services to suit your industrial and commercial needs, learn more about our pipe freezing services.
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