Dongfeng Bearing
LM Series Linear Ball Bearing Bush
Chrome steel linear ball bearing bush covering shaft diameters 6–60 mm, available in open and closed types. Recirculating ball retainer design delivers smooth, low-friction linear travel for CNC, automation, and general machinery.
Key Features
- Shaft diameter range 6–60 mm covered under one LM series ordering system
- Outer ring and balls in GCr15 chrome steel, hardened to HRC 60–64
- Closed type (UU) with rubber end seals and open type (OP) share identical outer dimensions
- PA66-GF glass-fiber nylon retainer maintains ball pitch under thermal cycling
- Dimensionally interchangeable with JIS B 1185 and ISO 10285 counterparts
- MOQ 100 pcs per size; H5 precision grade available on request for LM8–LM40
- Individual plastic bag packaging; bulk export carton packing for volume orders
- Used in CNC routers, 3D printer carriages, pick-and-place gantries, and automation slides
Common Sourcing Problems & How We Solve Them
Buyer Pain Points
- Inconsistent dimensional tolerances across batches cause machine downtime and re-work costs
- Suppliers unable to provide material certs, inspection reports or CE documentation for customs clearance
- Long lead times and high MOQ requirements make sample evaluation and first orders difficult
Dongfeng Solution
- ISO 9001:2015 process controls with CMM dimensional inspection on every production batch
- Full documentation package: material cert, SGS test report, CE declaration, packing list on request
- Flexible MOQ from 1 piece for samples; bulk order lead time 15–20 working days
Performance Data
- 10+ years of linear motion component manufacturing — 50+ export markets served
- Hardness tested to HRC 58–62; dimensional tolerance held to JIS / ISO / DIN standard grade
- CE & SGS certified; ISO 9001:2015 quality management system in production
Utility record
| Shaft Diameter Range | 6 mm – 60 mm |
|---|---|
| Outer Ring Material | Chrome Steel GCr15 (52100) |
| Ball Material | Chrome Steel GCr15 |
| Retainer Material | PA66-GF (Glass-Fiber Nylon) |
| Precision Grade | Normal / H5 |
| Types | Closed (UU), Open (OP) |
| Dynamic Load Rating (LM16UU) | 980 N |
| Hardness (Outer Ring) | HRC 60–64 |
| Standard Reference | JIS B 1185 / ISO 10285 |
Application fit notes
User Pain Point + Solution + Data
CNC router builders and automation integrators sourcing linear bearings face a common trade-off: specialty suppliers carry narrow size ranges, forcing multi-vendor procurement for a single machine that uses 6 mm shafts on a 3D printer axis and 40 mm shafts on a heavy-duty slide. The LM series covers 6–60 mm shaft diameters in one product family, with GCr15 chrome steel outer rings hardened to HRC 60–64 and PA66-GF retainers that hold ball pitch under thermal cycling. The LM16UU delivers 980 N dynamic load at a fraction of the cost of profile-rail carriages. Both closed (UU) and open (OP) types share identical envelope dimensions per JIS B 1185, so a housing bored for one type accepts the other without modification.
Complete Specifications
| Parameter | Value |
|---|---|
| Shaft Diameter Range | 6 mm – 60 mm |
| Outer Ring Material | Chrome Steel GCr15 (52100 equiv.) |
| Ball Material | Chrome Steel GCr15 |
| Retainer Material | PA66-GF Glass-Fiber Nylon |
| Precision Grade | Normal / H5 (selectable) |
| Types Available | Closed (UU), Open (OP) |
| Dynamic Load Rating (LM16UU) | 980 N |
| Hardness (Outer Ring) | HRC 60–64 |
| Standard Reference | JIS B 1185 / ISO 10285 |
Product Advantages
Single-Supplier Size Coverage
One LM series spans 6 mm through 60 mm. A machine builder using LM8 on a 3D printer Z-axis and LM40 on a press slide can source both from the same production line, with consistent material spec and QC baseline.
6–60 mm RangeGCr15 Chrome Steel, HRC 60–64
Outer ring and balls are both GCr15 (52100 equivalent), induction-hardened to HRC 60–64. The retainer is PA66-GF glass-fiber nylon, which maintains ball spacing under thermal cycling without warping.
GCr15 / HRC 60–64UU and OP Share Envelope
Closed type (UU) carries double rubber seals for dust resistance; open type (OP) has a longitudinal slot for split-housing installation and angular compensation. Both use the same outer dimensions-no housing redesign when switching types.
UU & OP; OPJIS B 1185 Interchangeable
Dimensions follow JIS B 1185 / ISO 10285. Drop-in replacement for THK, IKO, and MISUMI LM bearings of the same size. Verify shaft tolerance h6 for correct running clearance.
JIS StandardEnterprise Strength
Xiamen Dongfeng Bearing Mechanical & Electrical Co., Ltd.Ltd. - established 2014, 10+ years in linear motion bearing manufacturing. Our 5,000 m² Xiamen facility operates 12 production lines with 200+ employees. The linear bearing cell produces LM/LME/LMF/LMK series at 150,000+ pieces per month.
Certifications: ISO 9001:2015, CE conformity, SGS factory audit. Export markets: 50+ countries including Germany, Italy, USA, Japan, South Korea, and Brazil.
Pre-sales: Application load-life calculation and bearing size selection. After-sales: 18-month warranty, technical travel-life estimation service.
Manufacturing, Exhibition & Quality Controltrol
Production Process & Quality Assuranceance
Process: GCr15 raw tube -> CNC turning (outer ring, raceway groove) -> induction hardening (HRC 60–64) -> precision grinding (raceway) -> ball circuit assembly with PA66-GF retainer -> seal installation (UU type) -> 100% running smoothness test -> packaging.test -> packaging.ng.
Quality testing: Bore and outer diameter verified on air gauges (±2 µm), dynamic load validated on endurance rig, seal effectiveness tested with dust ingress simulation. Exhibitions: Regularly exhibited at PTC Asia (Shanghai), CIMT (Beijing), and Maker Faire Shenzhen.
FAQ
What is the MOQ and typical lead time?
Standard MOQ is 100 pcs per shaft diameter and type. For sizes in stock (LM6–LM30 range most common), lead time is 7–15 business days. Larger or less common sizes (LM40–LM60) are typically 20–30 days. Sample quantities of 10–20 pieces available for qualified buyers.
Are these compatible with standard linear shafts and housings?
Yes. LM series dimensions follow JIS B 1185 / ISO 10285, so they are dimensionally interchangeable with THK, IKO, and Misumi equivalents. Verify shaft tolerance h6 for correct clearance fit.
Can H5 precision grade be supplied for high-accuracy applications?
H5 grade is available on request for shaft diameters LM8 through LM40. Price and lead time differ from normal grade; please inquire with your target size and quantity.
How are LM bearings packaged for export?
Individual anti-corrosion oiled wrapping in plastic bags, then packed in partitioned cartons (50 pieces per carton for LM6–LM16, 25 pieces for LM20–LM30, 10 pieces for LM40–LM60). Wooden pallet packing available for bulk export orders.
What payment methods do you accept?
T/T (30% deposit, 70% before shipment). L/C at sight for orders above USD 15,000. PayPal for sample orders under USD 2,000. Western Union for small orders on request.
Do you offer OEM branding and custom packaging?
Custom logo engraving on outer ring available for 200+ piece orders. OEM branded packaging with buyer design available for 500+ piece orders. Custom seal colors and retainer materials can be discussed for high-volume orders.
Request a Quote for LM Series Bearings
Send your shaft diameter, type (UU or OP), quantity, and any OEM requirements - we reply within one business day with FOB Xiamen pricing and availability.
Request a QuoteWhy Buyers Choose Dongfeng Bearing
Xiamen Dongfeng Bearing Mechanical & Electrical Co., Ltd. — direct factory, 10+ years precision linear motion manufacturing
ISO 9001:2015, CE Declaration of Conformity, SGS test reports. Documentation available for EU and North American import requirements.
12 precision grinding and CNC machining lines; monthly output 500,000+ pieces across linear bearing and guideway series.
Germany, USA, Japan, South Korea, India, Southeast Asia and 40+ other countries. FOB Xiamen with DHL / FedEx / sea freight options.
Technical selection support before order. Dimensional drawing, material cert and inspection report with shipment. 12-month warranty on manufacturing defects.
Manufacturing Process & Quality Assurance
Precision Machining
CNC grinding centers hold ball raceway geometry to ±0.003 mm. Induction hardening targets contact zones to HRC 58–62 without embrittling the full body.
CMM Dimensional Inspection
Every batch passes coordinate measuring machine (CMM) verification. Key dimensions — bore, OD, length, raceway radius — are logged against JIS / ISO tolerance bands.
Certification & QC
ISO 9001:2015 controls govern raw material intake, in-process check, and final inspection. SGS and CE documentation issued on request for each shipment.
Trade Shows & Partnerships
Regular exhibitor at Canton Fair and Hannover Messe. Established supply partnerships with automation integrators and machine tool OEMs across Europe and Asia.
Customer Application Cases
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