STB / STU Series Compact Inline Flow Control Valve
Product Overview
STB / STU Series Compact Inline Flow Control Valve is a compact thread‑mounted Hydraulic valve. It is installed directly on pipelines of the hydraulic system to regulate hydraulic oil flow and control the movement speed of actuators for the Machine. STB is a bidirectional flow control model, while STU integrates a built‑in check valve to achieve throttling for forward flow and free reverse oil return. Worn or mis‑adjusted Hydraulic valve will cause speed fluctuation, jerky motion and unstable operation of the Machine. Its small‑size inline structure saves installation space, suitable for new‑equipment assembly and field maintenance of the hydraulic system.
Technical Specifications
- Model Series: STB / STU Series Compact Inline Flow Control Valve
- Valve Type: STB‑Bidirectional flow‑control Hydraulic valve; STU‑Flow‑control with built‑in check‑valve Hydraulic valve
- Port Thread: BSP / NPT
- Max Working Pressure: 21 MPa
- Flow Range: 0.5‑60 L/min (depends on model size)
- Working Medium: Anti‑wear mineral hydraulic oil
- Operating Temperature: ‑20℃ ~ +80℃
- Installation: Inline threaded pipe mounting
- Adjustment: Lockable graduated adjustment knob for precise flow setting
- Feature: Compact body, space‑saving pipeline layout
Working Principle
When hydraulic oil circulates inside the hydraulic system, turning the adjustment knob changes the opening area of the throttle orifice to set target flow. For STB version, oil is throttled in both directions to adjust the running speed of the Machine. For STU version: forward‑direction oil pushes the check‑valve element closed, and oil must pass through the throttle orifice for speed regulation. During reverse return stroke, oil pressure opens the internal check valve, allowing unobstructed oil flow without throttling resistance. If the throttle surface is scratched or check‑valve sealing is damaged, internal leakage will appear, reducing the working efficiency of the hydraulic system.
Core Advantages
1. Ultra‑compact inline design, saves pipeline space, flexible layout for the Machine.
2. Lockable graduated knob, easy repeatable flow setting, prevents accidental adjustment on‑site.
3. Two variants for different circuit demands: STB for bidirectional speed control; STU with built‑in check valve for forward throttling and fast reverse return in the hydraulic system.
4. Good sealing performance, stable flow output under medium‑pressure working conditions.
5. Simple installation and disassembly, direct fit to existing pipe circuits without extra machining.
6. Effectively solve faults such as cylinder speed drift, jerky movement and inconsistent actuator speed of the Machine.
Application Scope
This Hydraulic valve is widely applied to various industrial Machine, including automation equipment, hydraulic fixtures, small hydraulic presses, machine tools and light‑duty mobile machinery. As a key flow‑regulating component of the hydraulic system, it precisely controls the travel speed of hydraulic cylinders and rotation speed of hydraulic motors. Ideal for original assembly, circuit retrofitting and spare‑part replacement.