Standard Type Double-Sided Sealing Linear Bearings

LMUU Series Linear Bearings | High-Precision, Durable & Cost-Effective Linear Motion Solution

Product Overview

LMUU series linear bearings are general-purpose linear motion components conforming to metric standards, widely used in various industrial scenarios around the world. Their core function is to cooperate with cylindrical guide shafts to realize infinite linear reciprocating motion with low friction and high precision. With the advantages of simple structure, high reliability and outstanding cost performance, this series has become the preferred solution for linear transmission in compact spaces. It is suitable for light to medium-heavy loads and covers many fields such as precision manufacturing, automation equipment, civil equipment and so on.

In the model, “LM” represents adaptation to the common Asian metric dimension system, and “UU” indicates a double-sided contact sealing structure, which can effectively retain lubricating grease, block impurities, extend service life, and adapt to industrial environments with much dust and mild pollution.

Structure and Materials

2.1 Core Structure

LMUU linear bearings adopt a compact modular design, consisting of four core components, taking into account motion accuracy and structural rigidity with strong coordination.

1. Outer cylinder: It adopts a cylindrical structure as the main support of the bearing, which can be stably embedded into the equipment mounting seat to provide reliable load bearing. Some models can be matched with flange mounting to improve axial positioning performance.

2. Ball retainer: Made of resin material equivalent to DURACON M90, with built-in precision steel ball circulation channels, it guides the orderly rolling of steel balls and avoids mutual friction, ensuring stable and continuous motion and reducing energy loss.

3. Precision steel balls: As the core rolling elements, they are in point contact with the guide shaft, greatly reducing motion friction resistance. The uniform arrangement of steel balls can distribute loads, improving the bearing capacity and motion accuracy of the bearing.

4. Double-sided sealing rings: Adopting a contact design and fitting tightly with the guide shaft, they can not only block the intrusion of impurities such as dust and debris to prevent wear of steel balls and raceways, but also retain internal lubricating grease, reduce maintenance frequency, and adapt to complex working conditions.

2.2 Material Selection

Materials are selected to balance the wear resistance, high strength requirements and economic efficiency of industrial transmission. The core material parameters are as follows:

- Outer cylinder and steel balls: Made of high-chromium bearing steel (GCr15 or GCr15SiMn). After precision heat treatment, the hardness of the outer cylinder reaches HRC60-65, and the hardness of steel balls reaches HRC60-66. They have excellent wear resistance, impact resistance and deformation resistance, and can bear reciprocating loads for a long time.

- Retainer: Made of high-strength resin material, with lightweight, wear-resistant and noise-reducing characteristics, suitable for high-speed motion scenarios, avoiding wear and noise caused by metal contact, and reducing overall energy consumption.

- Sealing ring: Made of oil-resistant and wear-resistant rubber material, suitable for various lubricating media with stable sealing performance. It can maintain good sealing effect in the temperature range of -20℃ to 80℃, adapting to most industrial working conditions.

Core Features

3.1 Low Friction and High Precision

Relying on the point-contact rolling structure of steel balls and guide shafts, compared with traditional sliding bushings, the friction resistance is greatly reduced and motion efficiency is significantly improved, which can reduce motion jamming and wear. Stable accuracy can be maintained during long-term operation, suitable for precision positioning and high-speed reciprocating motion scenarios. Some models can meet the strict precision requirements of precision machine tools and semiconductor equipment.

3.2 Double-sided Sealing, Long-term Durability

The “UU” double-sided seal is the core advantage of this series. The sealing rings fit tightly with the guide shaft, effectively isolating impurities such as dust and water vapor, firmly locking lubricating grease, and reducing lubrication maintenance frequency. Combined with high-strength bearing steel and precision heat treatment process, the bearing has excellent wear and fatigue resistance and long service life, suitable for industrial equipment running continuously for a long time, reducing maintenance costs and downtime losses.

3.3 Compact Structure, Wide Adaptability

Adopting a non-flange cylindrical structure (flange type can be customized for some models), it is small in size and can be flexibly embedded into compact equipment structures, saving installation space and adapting to miniaturized and lightweight equipment design. Produced in accordance with standardized metric dimensions, it has strong interchangeability, facilitating equipment design, component replacement and batch assembly, reducing design and production costs.

3.4 Stable Load Bearing, Adaptable to Multiple Working Conditions

Steel balls are arranged in 4-6 rows (adjustable as required), which can evenly distribute radial loads with strong load capacity. Dynamic load ranges from 69N to 7350N, and static load ranges from 105N to 16000N, suitable for light and medium load scenarios. It has a certain eccentricity compensation ability, which can alleviate jamming caused by installation deviation, improve operation stability, and adapt to assembly requirements of different precision levels.

3.5 Outstanding Cost Performance, Suitable for Batch Application

With simple structure and mature production technology, large-scale standardized production can be realized, which has obvious cost advantages compared with high-precision customized linear bearings. Taking into account stable performance and versatility, it can adapt to various general machinery scenarios without additional customization, greatly improving procurement and production efficiency, making it the preferred linear transmission component for industrial mass production equipment.

Application Scenarios

LMUU series linear bearings are highly versatile and widely used in various mechanical equipment requiring linear reciprocating motion. Typical scenarios include:

1. Precision manufacturing equipment: Precision machine tools, CNC machine tools, semiconductor manufacturing equipment, testing instruments, etc., used for high-precision positioning and reciprocating motion of tools, worktables and detection heads to ensure processing and testing accuracy.

2. Industrial automation equipment: Robot arms, automatic conveyor lines, pneumatic/hydraulic actuators, assembly line equipment, etc., suitable for medium and high-speed reciprocating motion to improve equipment operation stability and efficiency, and reduce energy consumption.

3. Civil and light industrial equipment: 3D printers, textile machinery, food machinery, electric tools, fitness equipment, etc., with compact structure and high cost performance, suitable for miniaturized equipment design to meet daily operation and production needs.

4. Other scenarios: Medical equipment, chemical equipment, woodworking machinery, packaging machinery, etc., suitable for mild pollution, medium and low speed, medium and light load scenarios. Customized solutions can be provided according to special working conditions.

Usage Notes

1. Installation and coordination: It must be used with standard metric guide shafts. Ensure the parallelism of the two axes during installation to avoid eccentric installation, so as to prevent jamming and increased wear. The mounting seat shall be flat to ensure uniform stress on the outer cylinder and improve structural rigidity and motion accuracy.

2. Lubrication and maintenance: Only anti-rust oil is applied before delivery. Clean with kerosene before use, fill with suitable lubricating grease (such as lithium-based grease), and replenish regularly according to working conditions to extend service life. Shorten the maintenance cycle in dusty environments to avoid impurity intrusion.

3. Working condition limits: Conventional models are suitable for -20℃ to 80℃. Avoid direct use in high temperature, strong corrosion and unprotected high dust environments. For special working conditions, special sealing, material or lubrication schemes can be customized.

4. Load requirements: Do not use beyond the rated load to prevent deformation and damage of steel balls and raceways that affect accuracy and service life. During high-speed operation, verify the matching of speed and load to avoid excessive wear and heating.