Danfoss Waltech LL Series Hydraulic Fittings (Up to 100 bar)

The Waltech LL Series (Extra‑Light Duty) by Danfoss delivers lightweight yet dependable hydraulic compression fittings engineered to support low-pressure applications up to approximately 100 bar. Designed for small-diameter tubes (up to about 8 mm OD), these fittings combine precision engineering with user-friendly and repeatable assembly—making them ideal for compact and delicate hydraulic systems.

• Duty Class: Extra‑Light Duty (LL Series): up to ~100 bar
• Tube Outer Diameter: Typically up to 8 mm OD (e.g. 8 mm equal elbow)
• Material: Mild carbon steel with C6F free surface coating
• Assembly: Bite-type compression with cutting ring and nut, offering efficient and repeatable manual assembly
• Standards: Manufactured to DIN 2353 and compliant with ISO 8434-1

The LL Series is tailored for low-pressure systems requiring precision and compact form factor. Consider highlighting areas such as:

• Instrumentation & Control Systems: e.g., pressure sensors and gauges in industrial automation.
• Laboratory & Analytical Equipment: where leak-tight performance is essential in miniature piping circuits.
• Electronics Cooling Loops: small-diameter tubing in sensitive environments.
• Medical and Fluid Sampling Devices: low-pressure, space-constrained fittings for safe fluid transfer.

• Straight Male Connector: A direct connection between metric tube and a female-threaded port (BSPP, BSPT, or NPT). Commonly used for joining tubing to valves, pumps, and manifolds in low-pressure hydraulic circuits.
• Equal Straight Connector: Connects two lengths of tube with the same outer diameter. Useful for extending existing pipework or replacing damaged sections without altering layout.
• Equal Elbow (90°): Enables a sharp 90° turn between two equal-diameter tubes. Ideal for routing tubing around equipment or structural obstructions in compact systems.
• Male Elbow (90°): Joins a metric tube to a female-threaded port at a right angle. Saves space in tight installations and reduces tube bending requirements.
• Equal Tee: Connects three tubes of the same outer diameter in a “T” shape. Common in branching lines to supply multiple components from one feed.
• Reducing Tee: Connects three tubes of differing outer diameters, enabling step-down or step-up connections within a hydraulic system.
• Bulkhead Connector: Allows tubing to pass securely through a panel or bulkhead. Often used in equipment housings or enclosures to maintain integrity while connecting internal and external circuits.
• Swivel Female Connector: A tube-to-thread connection with a swivel nut, allowing easier assembly without twisting the tube. Useful for maintenance-heavy systems where fittings may need periodic disconnection.
• End Cap / Plug: Seals the end of a tube or port. Useful for system isolation, transport, or pressure testing.
• Reducer: Connects tubes or ports of different diameters, allowing integration of different circuit sizes without additional adaptors.

These fittings use a bite-type cutting ring for a secure, leak-free seal.

This is a brief overview of the installation process. Please consult the manufacturers handbook for full instructions:

1. Cut the Tube
   
   • Use a dedicated tube cutter or fine-tooth saw.
   • Ensure the cut is square, free from burrs, and the tube end is clean.
2. Insert into Fitting
   • Slide the nut and cutting ring onto the tube.
   • Push the tube into the fitting body until it bottoms out on the shoulder.
3. Pre-Assembly
   • Hold the tube firmly against the shoulder.
   • Tighten the nut by hand until snug.
   • Using a spanner, tighten 1 ¼ turns beyond finger-tight (per DIN 2353 guidelines for LL Series).
4. Check Bite
   • Disassemble and confirm the cutting ring has formed a continuous bite into the tube circumference.
   • Reassemble and tighten until resistance is felt—no further rotation is normally required.
5. Final Installation
   • Mount the pre-assembled fitting in the system.
   • Apply final torque according to LL Series specifications to ensure sealing without overtightening.

Tips for Success:

• Always use matching tube material and dimensions per DIN 2391 or EN 10305.
• Avoid reusing tubes where the bite surface is damaged or distorted.
• For stainless-steel tubes, pre-assembly on a dedicated tool or block is recommended to achieve proper bite.