KQ2S Series Straight Push-In Fitting with Inner Hex Hole

KQ2S Series Straight Push-In Fitting with Inner Hex Hole | SOLIH KQ2 Pneumatic One-Touch Connector

Brand: SOLH by Richge Technology | SMC Interchangeable KQ2S One-Touch Fitting, Male Thread Straight Connector With Internal Hexagon Socket

1. Product Overview

     KQ2S is a male-thread straight one-touch push-in fitting with built-in inner hex hole, belonging to SOLIH KQ2 series. One end for quick insertion of PU/PA tubing, the other male thread end with internal hexagon socket. It is specially designed for installation in narrow confined spaces and can be tightened by hex wrench, solving the limitation that standard male thread fittings cannot be operated with spanners. Fully interchangeable with SMC equivalent KQ2S, widely adopted for compact pneumatic circuits.

2. General Technical Specifications

     • Applicable Fluid: Compressed air, also compatible with vacuum, stable working range from -100kPa up to 1MPa

     • Operating Pressure: -0.1 ~ 1.0MPa, dual use for vacuum and positive pressure

     • Ambient Temperature: -5℃ ~ 60℃; For water medium: 0～40℃, freezing is prohibited

     • Compatible Tubing: PU / PA nylon hose, metric outer diameter φ3.2～φ16mm optional

     • Body Material: Nickel-plated brass for anti-corrosion & wear resistance; stainless steel optional for selected models

     • Seal Material: NBR Nitrile Rubber, reliable sealing and low airflow resistance

     • Connection Type: Push-in tube + male thread with inner hex hole. Thread section supports 360° rotational positioning for multi-angle piping layout

3. Model Specification Table (SOLH Standard)

4. Product Features

     • Built-in inner hex hole design: Standard hex socket at thread end. Hex key can be used for tightening in tight spaces, controllable installation torque to prevent thread stripping.

     • One-touch insert & release: Tool-free assembly. Insert tube to lock, press sleeve to release tube. Tube pulling force reduced by 20%, improving assembly efficiency.

     • Optimized straight flow channel: Low air resistance and pressure drop, maintaining stable flow rate for pneumatic circuits.

     • Double sealing construction: Special-shaped sealing components deliver stable leak-free performance over long service life, suitable for full vacuum and positive pressure range.

     • Miniature & lightweight: 23% smaller volume and 57% lighter than traditional fittings, saving installation footprint.

     • Strong interchangeability: Nickel-plated brass body for rust & corrosion resistance, direct drop-in replacement for SMC KQ2S series fittings.

5. Model Code Explanation (Take KQ2S08-02 as example)

     • KQ2: Series code for one-touch fitting, SOLIH KQ2 standard, fully compatible with SMC KQ2 series

     • S: Structure type: male thread straight fitting with inner hex hole (PTFE tape sealing; gasket sealing available)

     • 08: Compatible tube outer diameter: φ8 mm

     • 02: Male thread specification: Rc1/4

6. Installation & Operation Guidelines

     • Cut tubing vertically with flat and burr-free end. Fully insert tubing until seated for secure jaw locking to avoid air leakage.

     • Press release sleeve and pull tubing out smoothly during disassembly. Never yank hard to protect tubing and fitting jaws.

     • Thread mounting: Tighten with matched hex wrench with proper torque (M5:0.8N・m, Rc1/8:1.5N・m, Rc1/4:2.5N・m). Overtightening will cause thread stripping.

     • Wrap PTFE tape on male threads except pre-sealed models to enhance sealing performance.

     • Not applicable for oil, corrosive fluids or other non-air media except dedicated special versions.

     • Avoid radial or axial external force applied on fitting, which may cause fitting deformation and seal failure.

7. Typical Application Scenarios

     • Tube connection for male threaded ports on side of solenoid valves and cylinders with limited space

     • Internal piping for compact pneumatic modules and valve islands

     • High-density pneumatic wiring for automation equipment, machine tools and robotic arms

     • Pneumatic circuits requiring precise torque control

     • Vacuum adsorption circuits and medium-low pressure pneumatic systems

8. Difference Between KQ2S and KQ2H

9. Model Example for Quick Identification

     • KQ2H06-01S: External hex, φ6 tube, R1/8 thread, with thread sealant

     • KQ2S06-01A: Inner hex socket, φ6 tube, R1/8 thread, end face gasket seal

10. Selection Guide

     • Exposed regular installation, sufficient space, cost priority → Choose KQ2H

     • Narrow recessed mounting, frequent disassembly, anti-collision requirement → Choose KQ2S

     • Threads requiring repeated disassembly & reassembly → Choose KQ2S for stable gasket sealing