Gas rotary union LHK078-4Q

for airfor compressed air4-passage

Short Description
This LHK078-4Q rotary union features zero cross-leakage PTFE sealing, four independent air passages, a maximum rotation speed of 200 RPM and a maximum working pressure of 2 MPa. Constructed from anodized aluminum housing and hardened steel rotor, it is rated for gas media up to 100°C and is designed for winding and unwinding industrial equipment.

Core Sealing Performance Advantages
The LHK078-4Q uses a spring energy-storage composite PTFE sealing system to achieve zero gas cross leakage and ultra-low rotational friction. An internal elastic spring continuously presses PTFE sealing rings to maintain intimate contact between the static housing and rotating rotor under long-term operation. Four fully separated air passages are isolated by multi-layer composite sealing components to prevent cross-mixing or signal interference.
PTFE offers an extremely low friction coefficient, reducing rotation resistance and lowering drive motor load. The seals resist softening or deformation and maintain sealing elasticity at operating temperatures up to 100°C. Sealing assemblies are pre-assembled and tested in dust-free conditions; each unit undergoes air tightness inspection before shipment to ensure zero-leakage performance.

Premium Material & Precision Manufacturing Craft
All structural components are made from high-strength, wear-resistant metals with controlled surface treatments to extend service life and environmental adaptability.

• Rotor (shaft): 12L14 free-cutting steel, heat treated to 56–62 Rc, finished with black oxide coating for wear and corrosion resistance to reduce shaft surface abrasion and avoid clearance growth under long cyclic rotation.
• Housing: 6061-T6 aviation-grade aluminum alloy, Type 2 Class 2 red hard anodized for enhanced scratch, oxidation and corrosion resistance while keeping the unit compact and lightweight.

Internal flow channels are machined on CNC lathes to yield smooth, burr-free inner walls to minimize gas flow resistance and pressure loss. Components are deburred, ultrasonic cleaned and checked for dimensional tolerances before assembly to ensure accurate fits, stable rotation and low noise.

Complete Standard Technical Parameters
Model: LHK078-4Q. Four independent separated air channels. Standard port thread: 1/4" NPT. Applicable medium: clean compressed gas, non-corrosive industrial air. Max rotation speed: ≤200 RPM. Max working pressure: ≤2 MPa. Permissible operating temperature: ambient to 100°C. Surface treatment: red Type 2 Class 2 anodized aluminum housing, black oxide hardened steel rotor. Mounting: standard flange fixed installation. These parameters suit medium- and low-speed winding lines and mainstream pneumatic tension control systems for roll processing equipment.

Stable Running Performance for Heavy-Duty Continuous Production
Optimized internal bearing and matching structure enable smooth rotation with minimal friction torque and no jamming or abnormal noise under long-term vibration. The compact integrated structure prevents loosening from mechanical vibration, and the internal sealing design withstands frequent alternating rotation of winding and unwinding rollers. The unit is designed for continuous 24-hour cyclic operation; the PTFE composite seals extend service intervals and reduce maintenance downtime.

Wide Application Scope for Winding & Unwinding Machinery
This 4-channel pneumatic rotary union is developed for roll-to-roll equipment across multiple industries:

• Film processing: optical films, protective films, plastic packaging film winding and slitting (independent control of film tension, edge correction, roller clamping, auxiliary pneumatic cylinders).
• Textile: yarn winding machines, fabric unwinding rollers, slitting and coiling equipment for uniform tension control.
• New energy lithium battery: electrode winding machines for lithium-ion batteries supplying air for pole piece clamping, winding tension adjustment and roller pressing.
• Packaging & tape: adhesive tape winding machines, paper roll slitting and rewinding for flexible roll material lines.

Customization & Maintenance
Optional port thread specifications (NPT, G, PT), customized mounting flange dimensions and hole patterns, high-temperature or chemical-resistant sealing materials, and modified channel layouts are available. Standardized replaceable sealing components allow quick seal replacement without changing the entire unit, reducing downtime and improving production efficiency.

Technical Specifications

• Model Number: LHK078-4Q
• Number of Air Channels: 4 independent separated air passages
• Sealing Type: Spring energy-storage composite PTFE sealing system (zero cross-leakage)
• Standard Port Thread: 1/4" NPT
• Applicable Medium: Clean compressed gas, non-corrosive industrial air
• Maximum Rotation Speed: ≤200 RPM
• Maximum Working Pressure: ≤2 MPa
• Operating Temperature: up to 100°C
• Rotor Material & Treatment: 12L14 steel, heat treated 56–62 Rc, black oxide coating
• Housing Material & Treatment: 6061-T6 aluminum, Type 2 Class 2 red hard anodizing
• Internal Processing: CNC precision lathes, deburring, ultrasonic cleaning, dimensional tolerance detection
• Mounting: Standard flange fixed installation