1. Product Classification
All three models belong to domestic K-series spool-type pneumatic hand pull manual directional valves, actuated manually via a mushroom pull head without electric control. They are widely applied in machine tools, production lines, construction machinery, pneumatic fixtures and equipment safety air circuit start-stop control.
- K23R5-L8 / K23R5-L8-J(103): 2/3-way hand pull valve
- K25R5-L8: 2/5-way hand pull valve
2. Model Code Breakdown (National Standard Pneumatic Naming Convention)
General coding rule: K + Port & Position Code + R5 + L + Nominal Bore + -J(103)
1. K: General code for domestic classic K-series pneumatic directional spool valves
2. 23 = 2 positions 3 ports; 25 = 2 positions 5 ports
3. R5: Actuation type – hand pull with automatic spring return (R stands for pull operation, 5 for spring reset; pull out for locking position, release for automatic rebound)
4. L: Pipe thread connection type
5. 8: Nominal bore 8mm, standard port thread G1/4" (1/4 inch British thread) / Metric thread M12×1.25
6. J: Round mushroom-shaped pull head
7. (103): Factory internal material code / old alternative model number; fully interchangeable with standard K23R5-L8 with identical specifications, only differing in production batch coding
Model Comparison Table
Model Specification Main Application
K23R5-L8-J(103) 2/3-way hand pull valve with mushroom pull head & factory code 103 Single-acting cylinder, air circuit on-off & exhaust control, signal valve
K23R5-L8 Basic 2/3-way hand pull valve Bare valve body without J-type pull head (replaceable pull head available), same parameters as above
K25R5-L8 2/5-way hand pull valve Reciprocating motion control for double-acting cylinders with dual air inlet & return switching
3. Main Technical Specifications (Common for all 8mm bore models)
Item Specification
Working Medium Clean compressed air (lubrication-free or micro-lubricated air acceptable)
Working Pressure 0.2 ~ 0.8 MPa (standard pneumatic system pressure)
Effective Flow Area 10 mm²
Operating Pull Force Approx. 30N
Ambient & Medium Temperature 5℃ ~ 50℃
Air Leakage Rate ≤50 mL/min
Mechanical Service Life ≥2,000,000 reciprocating cycles
Valve Body Material Aluminum alloy with combined sealing rings
Mounting Type Dual-purpose: pipe threaded mounting & base threaded mounting
Port Size G1/4 thread
4. Structure & Working Principle
1. Structure: Equipped with built-in spool stem and O-ring composite seals; pull the mushroom head to shift the spool, release to reset automatically via internal spring. J-type adopts round anti-slip mushroom pull head for easy manual operation.
2. Air Circuit of K23R5 2/3-way Valve: 3 ports marked P (Air Inlet), A (Working Outlet), R (Exhaust Port)
- Normal reset state: P port closed, A port communicates with R port for exhaust
- Hand-pulled state: P port connects to A port for air supply, R port closed
Application: Single-acting spring return cylinders and air circuit switch & pressure relief
3. Air Circuit of K25R5 2/5-way Valve: 5 ports marked P (Air Inlet), A & B (Two Working Ports), R & S (Dual Exhaust Ports)
Air circuit switches between P→A & B→S or P→B & A→R upon pulling or resetting; specially designed for forward/backward control of double-acting cylinders.
5. Product Features
1. Pure mechanical manual operation, controllable even under power or air failure, ideal for emergency operation and workstation safety locking.
2. Lightweight aluminum alloy valve body with reliable sealing, durable in dusty working conditions.
3. Available as main control valve for small cylinders or pilot signal valve to operate large solenoid valves.
4. K23R5-L8-J(103) is a customized factory-coded version, fully replaceable with standard K23R5-L8 for procurement.
6. Application Scenarios
- K23R5 Series: Clamping & releasing of pneumatic fixtures, air blow gun switches, brake air circuit on-off and single-acting cylinder control
- K25R5 Series: Manual commissioning of pusher cylinders, lifting cylinders on assembly lines and offline manual testing of equipment
- Matching Assembly: Installed downstream of air compressor FRL combination unit in pneumatic circuits
7. Concise Version for Foreign Trade Quotation
- Model: K23R5-L8-J(103) 2/3 Way Hand Pull Pneumatic Valve
- K23R5-L8: Standard 2/3 Position Manual Valve (8mm Bore, G1/4 Port)
- K25R5-L8: 2/5 Way Hand Reset Pull Valve for Double-Acting Cylinders
- Structure: Spool Type, Spring Return, Aluminum Body, Knob Manual Actuation
- Working Pressure: 0.2-0.8MPa, Port Thread: G1/4, Nominal Bore: 8mm
