
Every connection in a fluid system is a potential leak point, making proper installation of tube fittings critical. Mistakes during installation can lead to safety hazards, environmental issues, and higher costs. Here’s a concise guide to avoiding common errors:
1. Overtightening or Under-Tightening
Tightening tube fittings “by feel” often results in over or under-tightening. Over-tightening can damage fittings and tubing, leading to failure and unnecessary repairs. Under-tightening causes leaks and pressure loss.

Stainless Instrumentation Fittings
Solution: Follow the manufacturer’s assembly instructions, typically one and a quarter turns past finger tight, using the recommended tools.
2. Skipping Inspection of Parts
Neglecting to inspect tubes and fittings for scratches, damage, or proper orientation can result in poor seals.
Solution: Before installation:
- Verify nuts and ferrules are the correct size and properly aligned.
- Ensure the tube is fully inserted and positioned against the fitting’s internal shoulder using a depth marking tool.
3. Using Scratched Tubing
Scratched tubing compromises the seal and can lead to over-tightening, damaging the fitting.
Solution:
- Use protective sleeves and padded racks to store and transport tubing.
- Avoid placing tubing on the ground or dragging it.
- Inspect thoroughly and cut off damaged sections before installation.
4. Imprecise Tube Cutting
Uneven or burr-filled cuts can prevent a secure seal.
Solution: Use specialized tools to cut tubing squarely. Deburr and clean the tubing to remove debris and imperfections before installation.
Key Takeaway
Proper installation starts with careful preparation and adherence to guidelines. Inspect materials, use the right tools, and follow manufacturer instructions for reliable, leak-tight connections.
QC Hydraulics provides high-quality twin ferrule instrumentation tube fittings, expert installation services, and training programs to ensure successful integration and long-term system performance. For superior products and support, contact QC Hydraulics today.