English  |
The LMK12LUU Flanged Linear Bearing is a low-cost, highly efficient linear motion system used in conjunction with a hardened cylindrical optical shaft to provide unlimited travel. The "K" designates a square-shaped mounting flange, while the "L" denotes its extended "Long" body. By housing a double-length ball circuit inside the steel cylinder, the LMK-LUU series provides significantly higher load capacities and better resistance to off-center loads than standard short-body bearings.
Use the dimensional data below to ensure accurate mounting onto your machine framework.
Item | Specification |
Model | LMK12LUU (Long type, Square flange) |
Inner Diameter (d) | 12 mm |
Outer Diameter (D) | 21 mm |
Total Length (L) | 57 mm |
Flange Square Size (K) | 32 mm × 32 mm |
Flange Thickness (H) | 6 mm |
Ball Circuits (Rows) | 4 Rows |
Bearing Material | High carbon chromium bearing steel |
Seal Option | UU (Wiper seals attached on both ends) |
(Note: We also supply LMK8LUU [8x15x45 mm] and LMK10LUU [10x19x55 mm] for smaller shaft requirements.)
Upgrading to a long-flange linear bearing offers several mechanical advantages for equipment manufacturers:
Direct Mounting: The square flange features four pre-drilled holes (PCD 32mm), allowing the bearing to be bolted directly and securely to the machine carriage without needing a separate pillow block.
High Precision & Low Friction: The steel balls rotate with minimal frictional resistance against the shaft, granting high-precision, smooth movement at high speeds.
Dependable Performance: Double seals (UU) keep dirt and debris out while retaining grease, ensuring a long life and resistance to wear in harsh environments.
The LMK12LUU is highly sought after for applications requiring robust linear translation in tight spaces:
CNC routers, laser cutters, and engraving machines.
Industrial and large-format 3D printers.
Automated packaging and processing machinery.
Auto parts, tractors, textile machinery, and water pump mechanisms.
We provide flexible supply chain solutions tailored to original equipment manufacturers (OEMs) and wholesalers.
Brand & Customization: We supply famous domestic brands or can customize the bearings to your specific technical drawings or samples.
Lead Time: Fast manufacturing with normal delivery between 3 to 15 days.
Payment Terms: 100% L/C at sight, 30% T/T deposit (70% against B/L or L/C), Western Union, and PayPal supported.
Q1: What is the difference between LMK12UU and LMK12LUU?
A: The LMK12UU is the standard-length bearing (approx. 30 mm long), while the LMK12LUU is the "Long" version (57 mm long). The long version essentially houses two sets of ball circuits back-to-back, doubling the load capacity and providing much better stability against twisting forces.
Q2: What is the difference between LMK, LMF, and LMH flanged bearings?
A: They function identically but have different flange shapes. LMK is a Square flange, LMF is a Round (circular) flange, and LMH is an Oval (cut-flange) shape for tighter spaces. All use the same internal bearing dimensions.
Q3: Does the LMK12LUU bearing need to be lubricated?
A: Yes. Although the "UU" designation means it has wiper seals to keep dust out, the internal ball bearings must be lubricated with a light machine oil or lithium grease to maintain smooth moving and low friction.
Q4: What type of shaft should I use with this bearing?
A: You must use a hardened, precision-ground linear optical shaft (metric 12 mm, g6 tolerance) to ensure the balls do not wear tracks into the metal. Standard unhardened steel rods will fail quickly.
The LMK12LUU Flanged Linear Bearing is a low-cost, highly efficient linear motion system used in conjunction with a hardened cylindrical optical shaft to provide unlimited travel. The "K" designates a square-shaped mounting flange, while the "L" denotes its extended "Long" body. By housing a double-length ball circuit inside the steel cylinder, the LMK-LUU series provides significantly higher load capacities and better resistance to off-center loads than standard short-body bearings.
Use the dimensional data below to ensure accurate mounting onto your machine framework.
Item | Specification |
Model | LMK12LUU (Long type, Square flange) |
Inner Diameter (d) | 12 mm |
Outer Diameter (D) | 21 mm |
Total Length (L) | 57 mm |
Flange Square Size (K) | 32 mm × 32 mm |
Flange Thickness (H) | 6 mm |
Ball Circuits (Rows) | 4 Rows |
Bearing Material | High carbon chromium bearing steel |
Seal Option | UU (Wiper seals attached on both ends) |
(Note: We also supply LMK8LUU [8x15x45 mm] and LMK10LUU [10x19x55 mm] for smaller shaft requirements.)
Upgrading to a long-flange linear bearing offers several mechanical advantages for equipment manufacturers:
Direct Mounting: The square flange features four pre-drilled holes (PCD 32mm), allowing the bearing to be bolted directly and securely to the machine carriage without needing a separate pillow block.
High Precision & Low Friction: The steel balls rotate with minimal frictional resistance against the shaft, granting high-precision, smooth movement at high speeds.
Dependable Performance: Double seals (UU) keep dirt and debris out while retaining grease, ensuring a long life and resistance to wear in harsh environments.
The LMK12LUU is highly sought after for applications requiring robust linear translation in tight spaces:
CNC routers, laser cutters, and engraving machines.
Industrial and large-format 3D printers.
Automated packaging and processing machinery.
Auto parts, tractors, textile machinery, and water pump mechanisms.
We provide flexible supply chain solutions tailored to original equipment manufacturers (OEMs) and wholesalers.
Brand & Customization: We supply famous domestic brands or can customize the bearings to your specific technical drawings or samples.
Lead Time: Fast manufacturing with normal delivery between 3 to 15 days.
Payment Terms: 100% L/C at sight, 30% T/T deposit (70% against B/L or L/C), Western Union, and PayPal supported.
Q1: What is the difference between LMK12UU and LMK12LUU?
A: The LMK12UU is the standard-length bearing (approx. 30 mm long), while the LMK12LUU is the "Long" version (57 mm long). The long version essentially houses two sets of ball circuits back-to-back, doubling the load capacity and providing much better stability against twisting forces.
Q2: What is the difference between LMK, LMF, and LMH flanged bearings?
A: They function identically but have different flange shapes. LMK is a Square flange, LMF is a Round (circular) flange, and LMH is an Oval (cut-flange) shape for tighter spaces. All use the same internal bearing dimensions.
Q3: Does the LMK12LUU bearing need to be lubricated?
A: Yes. Although the "UU" designation means it has wiper seals to keep dust out, the internal ball bearings must be lubricated with a light machine oil or lithium grease to maintain smooth moving and low friction.
Q4: What type of shaft should I use with this bearing?
A: You must use a hardened, precision-ground linear optical shaft (metric 12 mm, g6 tolerance) to ensure the balls do not wear tracks into the metal. Standard unhardened steel rods will fail quickly.
