In Machinery, What Is a Roller Screw?

The planetary roller screw is a mechanism that converts rotary motion into linear motion. The rolling element between the nut and the screw is a threaded roller. The numerous contact lines make the planetary roller screw have a very strong bearing capacity.

Planetary roller screw

Planetary roller screws are classified into: roller non-circulating (RGT series and RGTB series), roller circulating (RGTR series). Reverse planetary roller screws (RGTI series) are also available. Lead accuracy is divided into two levels: KL5 = ± 0.005mm, KL10 (standard) = ± 0.01mm. (315mm stroke)

Category: RGT series and RGTB series

RGT series and RGTB series planetary roller screws are mainly composed of main screw, nut and roller.

Planetary roller screws are suitable for the following industries:

-CNC machine tools-Robots,

-Aeronautical (aircraft / helicopter) -Aerospace (rocket / satellite),

-Weaponry (tank / cannon / missile / aircraft carrier / nuclear submarine)

-Precision injection molding machine-Mechanical press,

-Medical industry-Measuring instruments

-Special Machine Tool-Laser Equipment

-Petroleum Industry-Chemical Industry

-Optical Instruments-Metallurgical Equipment

-Automotive Industry-Servo Electric Cylinder

Here, the special application of planetary roller screws in the defense / military industry needs special introduction,

High load capacity: Planetary roller screws are in line contact, and the increase in contact surface greatly improves the load capacity and rigidity. Therefore, it has high rigidity and high load carrying capacity, which is more than 3 times (more than 10 times) higher than the ball screw pair of the same specification.
Impact resistance: Ability to withstand impact loads is very strong, and the work is reliable.

Comparison of roller and ball screw

Comparison of movement mechanism and force state ^[1]

Operating temperature

The suitable working temperature of planetary roller screw is between -40 and + 130 . planetary roller screws are suitable for operating temperatures between -40 ° C and + 130 ° C. The highest working temperature is between -50 and + 200 .

About working temperature of oil wiper wipers:

There is a type of oil wiper. The highest working temperature of the material using "POM polyformaldehyde" is 90 ° and the highest working temperature of the material using "PTFE polytetrafluoroethylene" is 140 ° C. We have to kind of wipers. The max. Operation temperature with "POM" is 90 ° and with "PTFE" wipers the max. Temperature is140 °.