Expander Heads for HVAC Copper & Refrigeration Tubing

Build full-bore, brazed joints without extra fittings. These Imperial and Mastercool expander heads and tube expander kits are designed for soft copper and compatible thin-wall tubing used on HVAC and refrigeration systems across Australia.

What these expander heads are used for

Expander heads are swaging tools that enlarge the end of a tube so another tube can slide inside for a brazed or soldered joint. That means fewer couplings, fewer potential leak points and smoother internal flow through your copper lines.

In HVAC work, you’ll typically use expander heads on refrigeration line sets and heat pump pipework whenever you want a clean, brazed connection instead of adding extra fittings.

Imperial Xpandr™ heads & kits

Imperial 175EX Tube Expander – Xpandr Swaging/Expanding Kit

The Imperial 175EX Xpandr kit is a compact manual expander set for everyday copper line work. It expands tube for brazed or soldered joints in seconds and its floating jaw head design helps keep the tube self-centred for fast, accurate alignment.

• Designed for soft copper and compatible thin-wall tubing.
• Re-rounds slightly deformed tube ends before brazing.
• Includes five main heads: 3/8", 1/2", 5/8", 3/4" and 7/8".
• Compact size makes it ideal for service work and tight spaces.

See full details on the Imperial 175EX Tube Expander – Xpandr Swaging/Expanding Kit .

Imperial replacement expander heads for 175EX

Your Expander Heads collection also includes individual Imperial heads sized to suit the 175EX tool body. These cover common HVAC tube outside diameters such as 3/8", 1/2", 5/8", 3/4", 7/8", 1", 1 1/8", 1 3/8" and 1 5/8". Use them to replace worn or missing heads or to expand the range of tube sizes you can handle with a single kit.

Mastercool Hydra-Swage hydraulic expander kits

For higher volumes or tougher materials, the Mastercool Hydra-Swage hydraulic expander takes the effort out of tube expansion. A compact hydraulic pump drives interchangeable heads to expand copper, aluminium and soft steel tubing.

• Hydraulic power for consistent, low-effort expansion.
• Head set typically covers 3/8" through to 1 1/8" OD tubing.
• Supplied with inner/outer reamer and carry case for service work.

For hydraulic power and a wider size range, see the Mastercool Tube Expander Tool Kit 71600-A and related hydraulic flaring and expanding kits.

How to choose the right expander head

• Tube material: These tools are intended for soft copper and compatible thin-wall tubes. Follow manufacturer guidance if you need to anneal harder tube before expansion.
• Tube size: Heads are sized to the tube’s outside diameter. Always confirm the OD of your copper line and match it to the product title and description before ordering.
• Manual vs hydraulic: Choose the Imperial 175EX manual Xpandr kit for fast, compact everyday work or a Mastercool Hydra-Swage hydraulic kit when you frequently work on larger or thicker-wall tube.
• Future-proofing: Busy teams often keep a full manual kit plus extra heads in common sizes and a hydraulic kit in the workshop for heavier jobs and retrofits.

Good expansion supports energy efficiency & compliance

Well-expanded and properly brazed joints help reduce refrigerant leak points, keep copper runs full-bore for better flow and heat transfer, and support long-term efficiency and reliability. That’s good for your clients, and it aligns with Australian guidance on energy-efficient, leak-tight HVAC installations.

Always follow the relevant refrigerant-handling codes of practice and licensing requirements when modifying systems that contain or will contain controlled refrigerants.

Using expander heads – practical tips

• Cut the tube square with a quality tube cutter and deburr the inside and outside edges.
• Select the expander head that matches the tube’s outside diameter – avoid using “close enough” sizes.
• Expand in several small pulls rather than one big hit to reduce the risk of splitting or over-thinning the wall.
• Inspect the expanded end for cracks or distortion before brazing and remake any joint you are not confident in.
• Pair your expander heads with an HVAC brazing kit and use nitrogen purge where recommended to minimise internal oxide build-up.

Licensing note: Any work on RAC systems that contain or will contain controlled refrigerants should only be carried out by appropriately licensed personnel in line with ARCtick and state WHS requirements.

Pair expander heads with other HVACShop tools

• Tube expanders for complete kits and expander bodies to suit these heads.
• Flaring and swaging kits for flare work and alternative swaging methods on copper tube.
• Tube cutters and deburring tools to prepare tube ends before expansion.
• Portable gas torch and brazing kits to create strong, neat brazed joints once the tube has been expanded.
• Learn more about flaring and swaging in our blog posts Types of Flaring Tools for Plumbing and HVAC Flaring Tool: Essential Equipment Explained.