In the maintenance and procurement of hydraulic supplies for factories, the MK and MG series throttle valves from Rexroth are highly prone to confusion. Although they look 99% identical on the outside, their internal structure and operating principles are completely different.
Mixing them up or intentionally replacing these two valve codes incorrectly poses an immense risk to your factory's machinery system. Let's analyze the differences in detail with QME right below!
1. 90% IDENTICAL APPEARANCE - A VISUAL TRAP WHEN PURCHASING:
For non-technical personnel or those who haven't researched thoroughly, judging purely by external appearance can easily lead to mistakes:
- Uniform design: The housing specifications, threaded port dimensions, and mechanical graduated adjustment knobs of both the MK and MG series are exactly the same.
- Identification feature: The only identifying mark is the letter "K" or "G" engraved very small on the product label/code.
- Practical example:
+ MG series code: MG 8 G1X/… (Code R900422145)
+ MK series code: MK 8 G1X/... (Code R901226940)
2. 100% DIFFERENT IN MECHANICAL STRUCTURE AND OPERATING PRINCIPLE:
The difference in cost and performance lies entirely in the precision mechanical structure hidden inside the valve body.
MG Series – Two-way throttle valve (Streamlined structure):
- Structure: The interior consists only of a simple needle valve mechanism.
- Operating principle: Hydraulic oil passing through the valve in either direction (from A to B or vice versa) will have its flow restricted.
MK Series – One-way throttle valve (Complex structure):
- Structure: Integrated with an additional Bypass check valve assembly (including a Poppet and a return spring).
- Operating principle: This mechanism allows the oil to be throttled in one direction, while in the reverse direction, it pushes the poppet open to allow the oil to return completely unrestricted (Free Flow).
- Cost: Due to high precision machining requirements, the MK series is always 20% - 35% more expensive than the MG series.
3. SERIOUS CONSEQUENCES OF INSTALLING THE WRONG VALVE CODE IN A FACTORY SYSTEM:
In many cases, factories wanting to cut material costs, or purchasing departments mistakenly ordering the MG series to replace the MK series (where the system absolutely requires free oil return). This leads to serious technical failures:
- Circuit blockage and pressure loss: The return oil line is choked, causing a severe pressure drop in the control system.
- Rapid overheating: The lost pressure is converted into heat energy, rapidly heating up the hydraulic oil.
- Seal destruction: Oil temperatures rising beyond the threshold will denature, age, and destroy the entire seal system of adjacent equipment (pumps, cylinders, directional valves).
- Sudden machine shutdown: Disrupts the production line, incurring repair and maintenance costs many times greater than the value of the valve.
4. WHERE TO BUY REPUTABLE GENUINE REXROTH HYDRAULIC VALVES?
To ensure the factory's hydraulic system operates stably and to avoid the "money lost, disaster strikes" risk of buying the wrong code or counterfeit goods, customers need to choose a reputable supplier.
QME - Proud to be a direct authorized dealer for Rexroth in Vietnam, we commit to:
- In-depth technical consultation: A team of experienced engineers ready to help check the catalog and select the exact or correct equivalent code for your system.
- Large-capacity stock availability: Always having a ready source of goods for quick supply from Rexroth.
- 100% Genuine: Full Certificate of Origin (CO) and Certificate of Quality (CQ) from the manufacturer.
- Warranty policy: Strictly following the global standards of Bosch Rexroth.
CONTACT QME NOW TO RECEIVE A QUOTE AND FREE TECHNICAL CONSULTATION!
