Shijiazhuang Laiye Imort& Export Trading Co., Ltd. is one of the leading manufacturers and suppliers of in-line throttle check valve in China, also supports customized service. If you're going to wholesale high quality in-line throttle check valve made in China, welcome to get pricelist from our factory.
What This Valve Actually Does
You have a cylinder that moves too fast. Or a motor that jerks at startup. You need to slow down one direction but keep the other direction full speed. That is exactly where an in-line throttle check valve fits.
This one is a screw‑in, tube‑type valve. You put it directly into a pipe run – no subplate, no extra hose tails. One port pair (A→B) gives adjustable restriction; the opposite direction (B→A) opens a separate internal check valve, so oil flows freely back.
No electronics. No pilot lines. Just a mechanical solution that has worked in hydraulic systems for decades.
How You Will Use It
Real Installation Examples
Controlling a gravity‑lowered mast
On a small forklift or aerial work platform, lowering speed is often too fast when the load is heavy. Install this valve in the line going to the rod end of the lift cylinder. Adjust the hand knob until the mast descends smoothly – even with an empty platform. Reverse flow (pump raising the mast) goes through the check valve without restriction, so lifting speed stays unchanged.
Metering oil to a clutch pack
Some industrial machines need a slow engagement to avoid shock. Place the valve in the pressure line before the clutch valve. The needle characteristic gives fine control near closed position – about 15 full turns from shut‑off to full open. You can set engagement time from 0.5 to 5 seconds without feeling a step change.
Metering oil to a clutch pack
Bleed and bypass applications
Because the check valve cracks at only 0.05 MPa, you can use this valve as a controlled bypass around a filter or cooler. Forward flow goes through the throttle – you decide how much. Reverse flow is nearly unrestricted.
What You Will Notice During Adjustment
The hand knob has a lock nut. Tighten it after setting – vibration from pumps or engines will not change the flow rate. On jobsites with old machines, this matters.
Each full turn of the knob gives a predictable flow change. The needle is machined with a linear taper, not a sharp cut‑off. You will not go from zero to full flow in half a turn.
The stop screw prevents over‑tightening. You cannot jam the needle into the seat hard enough to damage it.
How We Make Them – So You Know What You Are Buying
Our production is not mysterious. Each in-line throttle check valve goes through:
Forged body (no sand casting cavities). We cut a sample from every batch and check porosity.
CNC thread milling – G, NPT, or Rc threads to ISO 7‑1 / ASME B1.20.1. Thread gauges used on 100% of parts.
Needle grinding – surface finish Ra 0.4 µm. Smoother = less erosion at high velocity.
Assembly and test – each valve is mounted on a test stand. Forward flow curve measured at 5, 10, 20, 30, 40, 50 L/min. Reverse leakage checked at 315 bar – zero visible drip.
Label and pack – with protective plastic caps on both ports.
We started making hydraulic valves in 2008. In 2014 we moved to our own 5,000 m² plant. In 2020 we became an approved supplier for a European agricultural OEM (they test every batch on their own flow bench). Today we produce about 8,000 pieces per month, mostly for industrial and mobile applications.
What You Get When You Order
- One valve, ready to install (ports are clean, no metal chips – we blow them with compressed air).
- A datasheet with flow curves for your specific bore size (6/10/15/20 mm).
- CAD model (STEP file) on request – usually sent within 4 hours.
- 12‑month warranty against manufacturing defects. Seals are consumables but we include one spare set per valve for the first year.
Hot Tags: in-line throttle check valve, China in-line throttle check valve, manufacturers, suppliers, factory
