
Precision Hydraulics™ is Chen Hsong’s proprietary servo-hydraulic control system. Refined over more than 30 years, backed by nearly 70 years as one of the world’s largest injection molding machine manufacturers, it coordinates four layers of engineering into a single integrated system.
Heavy-duty, high-precision linear guide rails reduce friction and keep every axis true.
Balanced dual injection cylinders and balanced clamping cylinders distribute force symmetrically.
High-precision linear transducers on the main motion axes feed exact position data back to the controller.
a responsive servo-hydraulic drive with closed-loop control over position, speed, pressure, and barrel temperature.
These four layers are tuned together using fluid dynamics simulation software and hands-on optimisation by Japanese and European hydraulic specialists. The result is a machine where the motion curve you programme is the motion curve you get.

In a standard hydraulic circuit, fast movement creates pressure drops, overshoots, and oscillation at switchover. At slow speeds these faults are invisible. At production speeds they show up as flash, sink marks, and weight variation. Most servo-hydraulic machines manage these problems at the pump level. Precision Hydraulics™ removes them across the whole circuit.
Japanese hydraulic experts mapped the full circuit in simulation and eliminated unnecessary pressure drops through multiple rounds of optimisation.
A patented pressure-relief method releases pressure quickly without reversing the pump, cutting transient shock and component wear.


Closed-loop control holds position, speed, pressure, and temperature to the programmed profile.
The servo drive responds on demand and rests during cooling, saving up to 80% energy compared with older fixed-pump hydraulic machines.
Three things working together give AIR Buffer™ its sensitivity: high hydraulic precision, optimised mechanical design, and patented control algorithms.
A precision pressure sensor reads through the servo system and detects an obstacle as thin as 0.1 mm during top-speed clamp closing.
Try it.
Put a sheet of normal A4 paper between the mold of a JM168-MK6 running at 100% speed and 100% pressure. The machine detects it, stops, and reopens. The paper comes out flat, not even punctured.
Large machines too.
The same test works on a 3,600-ton two-platen. AIR Buffer™ is available across all Precision Hydraulics™ machines, from 88T toggle to 6,500T two-platen.


Targets the edge cases that test any machine: high-pressure stabilisation at cycle start, precise low-speed control, clean switchover at high injection speeds.
An optional control pack that makes difficult jobs routine and routine jobs smoother.
| Layer | Components | What it does |
|---|---|---|
| Motion Design | Balanced dual injection cylinders, balanced clamping cylinders | Symmetrical force distribution, no off-axis loading |
| Mechanical Structure | Heavy-duty linear guide rails | Low friction, accurate axis guidance, longer component life |
| Feedback | High-precision linear transducers on main axes | Exact position data for closed-loop correction |
| Servo Control | Servo-hydraulic drive, closed-loop over position / speed / pressure / temperature | On-demand power, smooth response, low idle draw |
| Pressure Relief | Patented non-reversing method | Fast pressure drop without pump reversal shock |
| Mold Protection | AIR Buffer™ ( pressure sensor+patented algorithms ) | 0.1 mm obstruction detection at full clamp speed |
| Spec | Value | Notes |
|---|---|---|
| Repeatability | ±0.05% | MK6 main motion axes |
| Mold Protection Sensitivity | 0.1 mm | AIR Buffer™, full speed |
| Energy Saving | Up to 80% | vs older fixed-pump hydraulics |
| Dry Cycle | From 1.5 sec | Model dependent |
| Injection Speed Range | 300 to 1,000 mm/s | Model dependent |
A disposable-cup molder ran parts on a high-end Ferromatik at over 3.5 seconds a cycle. A standard SPEED168 with Precision Hydraulics™ ran the same part, with no exotic add-ons.
What the SPEED168 had:
2.9 sec (vs 3.5+ sec)
300 mm/s
12 g × 2 cavities
±0.05%
>99.8%
Standard servo-hydraulic machines control flow and pressure at the pump. Precision Hydraulics™ optimises the whole hydraulic circuit and coordinates four layers: motion design, mechanical structure, transducer feedback, and closed-loop servo control, refined together over 30+ years by Japanese and European specialists.
Standard protection slows the clamp and watches for a pressure rise to sense contact. AIR Buffer™ reads a precision pressure sensor through the servo system at full clamp speed and catches a 0.1 mm obstruction, then reopens immediately. It works across the full range, from 88T to 6,500T.
Repeatability on the main motion axes of the MK6 series. Other machine families carry their own figures for different axes and metrics.
Up to 80% less than older fixed-displacement (fixed-pump) hydraulic machines. The servo drive draws power on demand and rests during cooling.
Have a question that is not covered in the FAQ? Our AI assistant can help you find answers, products, or the right next step.
Choose Your Region
The Chen Hsong Group has offices and distributors all around the globe.
Select your region from below or search our global list of distributors.
This page is currently in development. Our team is putting it together, please check back shortly or reach out if you need anything in the meantime.
| Service | Cookies | Description |
|---|---|---|
| Google Analytics | _ga _ga_* _gid _gat _gcl_au | Google Analytics is used to collect anonymous statistics about how visitors use our website, such as pages visited, time spent on site, and traffic sources. This helps us understand and improve the user experience. |
| Service | Cookies | Description | |
|---|---|---|---|
| Google Analytics | _ga _ga_* _gid _gat _gcl_au | Google Analytics is used to collect anonymous statistics about how visitors use our website, such as pages visited, time spent on site, and traffic sources. This helps us understand and improve the user experience. |