1 Model Information & Technical Parameters

Model：BTW 150 CM/SP

Dimensions

Bore d：150 mm

Outer diameter D：225 mm

Height H：90 mm

Contact angle：60°

Number of rows：2 rows of balls

Axial load capacity：Bidirectional

Housing washer type：Two-piece design for double row angular contact thrust ball bearing

Outer ring locating shoulder：None

Re-lubrication facility：Not available

Accuracy class: SP precision grade

Structure series: Standard heavy-duty BTW series

Seal: Open design, no seals

Surface coating: Uncoated

Pre-lubrication: No lubricant supplied from factory

Code Explanation

BTW: Standard heavy-duty double row angular contact thrust ball bearing with two-piece housing washer, 60° contact angle, bidirectional axial load capacity, heavy-duty spindle thrust bearing.

150: Nominal matching shaft diameter 150 mm.

CM: Machined one-piece metal cage, reinforced for heavy load operation.

SP: Precision accuracy grade for heavy-duty precision spindle applications.

Load & Speed Data

Basic dynamic load rating Cr：127 kN

Basic static load rating C0r：440 kN

Permissible speed, grease lubrication：3 000 r/min

Permissible speed, oil-air lubrication：3 600 r/min

Material & Additional Properties

Rolling element material: Bearing steel

Indicative carbon footprint：39.1 kg CO₂e

Net weight：10.6 kg

eClass code：23-05-10-02

UNSPSC code：31171531

Suffix Explanation

BTW: Heavy-duty oriented double row angular contact thrust ball bearing with separated two-piece housing washers and 60° contact angle, capable of bidirectional axial loads. Compared with BTM high-speed series, it features higher axial rigidity and greater load capacity at the cost of lower limiting speed, suitable for heavy cutting conditions.

150: Reference shaft journal dimension 150 mm.

CM: Precision machined metal cage with high structural strength, resistant to impact and deformation under sustained heavy loads.

SP: Precision grade with tight control on dimensional and axial rotational accuracy to reduce axial runout under heavy loads.

Important reminder: BTW series thrust ball bearings are mainly designed for bidirectional axial loads and can only withstand minimal radial load. Complete heavy-duty spindle assemblies must adopt radial bearings (NN series double row cylindrical roller bearings) in combination. No locating shoulder on outer ring; axial restraint relies entirely on bearing housing. Without built-in lubrication channels, continuous on-line re-lubrication during running is impossible, suitable for periodic maintenance lubrication. Open bearing without integral seals; oil seals or labyrinth seals shall be installed on housings to block coolant and dust. No pre-filled grease upon delivery.

Alternative variants:

BTW150 CM (Normal precision for heavy-duty general rotating equipment)

BTW150 CM/P4 (P4 precision grade for heavy-duty spindles)

BTW150 CM/SP (SP precision grade, preferred for heavy-duty precision machining equipment)

2 Structure & Operating Characteristics

BTW 150 CM/SP is SP precision grade standard heavy-duty double row angular contact thrust ball bearing with 60° contact angle, two-piece housing washer construction and machined metal cage for bidirectional axial load support. The large 60° contact angle delivers exceptional axial rigidity and can endure heavy alternating bidirectional axial loads. In comparison with 40° contact angle bearings, load capacity is greatly improved while maximum rotational speed decreases, ideal for heavy cutting and high-feed heavy-duty machine tools. Machined metal cage possesses high rigidity and tolerates impact loads without easy deformation under long-term heavy loads.

Core features: 60° large contact angle + BTW heavy-duty series design + SP precision axial accuracy + high-strength machined metal cage. Classic spindle matching scheme: NN series double row cylindrical roller bearing for radial support paired with BTW thrust bearing for bidirectional axial positioning, standard configuration for heavy gantry machine tools and large CNC lathes.

Selection guide:

BTW150 CM/SP (SP precision grade for heavy machining centers, gantry boring & milling machines, large CNC lathe precision spindles requiring high axial rigidity for heavy cutting)

BTW150 CM/P4 (P4 precision grade for general heavy-duty precision spindles)

BTW150 CM (Normal precision for heavy fixtures and non-precision heavy-duty rotating machinery)

3 Core Performance Advantages

1. Large 60° contact angle provides outstanding axial rigidity and strong bidirectional load capacity to cope with massive axial forces generated during heavy cutting.

2. Exclusive BTW heavy-duty internal geometry optimizes rolling contact performance and delivers excellent static load resistance against cutting impact loads.

3. Double row ball with two-piece housing washer structure accepts axial loads in both directions to realize bidirectional spindle axial limitation.

4. SP precision grade suppresses spindle axial play under heavy loads and stabilizes dimensional accuracy for finishing large workpieces.

5. Machined metal cage features high structural strength, good impact resistance and temperature resistance, resisting deformation and damage during continuous heavy-duty operation.

6. Standardized two-piece housing washer design ensures good interchangeability with existing spindle components for convenient maintenance replacement on heavy equipment.

4 Typical Application Fields

4.1 Spindles of heavy vertical & horizontal machining centers, gantry boring and milling machines

Combined with NN double row cylindrical roller bearings to carry heavy bidirectional axial loads

4.2 Heavy-duty spindles of large CNC lathes and turn-mill machines

Withstand alternating axial loads during heavy cutting

4.3 Precision spindles of large cylindrical grinders and roll grinders

Stable axial positioning and vibration suppression under heavy load

4.4 Heavy-duty precision rotary fixtures and large automatic indexing devices

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

SP precision bearings should be assembled in clean dust-controlled workshops. Remove all contaminants on shaft shoulders, housing bores and spacer mating surfaces. Strictly follow installation orientation of two-piece washers to avoid ball displacement. Direct hammer impact on balls or cage is strictly forbidden. No outer ring locating shoulder; ensure flat full contact of washer surfaces and achieve axial limitation via bearing housing. Load sharing principle: radial loads shall be transferred to matched cylindrical roller bearings, this bearing only undertakes axial force. Without built-in re-lubrication grooves, continuous running oil supply is unavailable; lubricant replenishment shall be arranged during periodic shutdown maintenance. Equip bearing housings with oil seals or labyrinth seals to prevent dust and coolant from entering raceways. Metal cage exhibits superior heat resistance compared with non-metallic cage, yet persistent abnormal high temperature should still be avoided.

5.2 Selection Guidance

Heavy-duty precision spindle matched with NN double row cylindrical roller bearing, bearing heavy bidirectional axial loads, high axial rigidity required → BTW150 CM/SP

General heavy-duty precision spindle with moderate precision demand → BTW150 CM/P4

Heavy-duty rotating equipment without strict precision requirements → BTW150 CM

Important notice: Never use BTW thrust bearing alone to support radial loads; uneven ball loading will trigger premature fatigue spalling. Absence of continuous on-line lubrication structure requires shortened maintenance intervals for long-term continuously operating heavy machinery.

5.3 Lubrication Maintenance Instruction

No lubricant pre-filled at factory. Grease lubrication and oil-air lubrication are both applicable. Without annular lubrication passages, non-stop on-line oil replenishment cannot be realized; lubricant filling must be completed during scheduled machine shutdown. Continuously monitor spindle temperature rise and axial vibration. Moderate temperature increase under heavy cutting is normal; inspect lubrication system immediately when excessive overheating occurs.

5.4 Environmental Application Notes

Open construction without built-in seals; reliable sealing devices must be mounted on bearing housings. Balls and raceways are sensitive to erosion from dust and coolant. Contaminant intrusion easily causes raceway scratches and pitting, leading to rapid accuracy loss. Although metal cage offers good heat resistance, prolonged operation at excessive temperature should be avoided to slow contact fatigue of raceways.

6 Fault Identification

Common failure modes: Continuous dimensional drift of heavy machined workpieces, excessive spindle axial play under heavy load, abnormal temperature rise during operation, periodic abnormal noise, ball indentation, raceway fatigue spalling. Primary causes: Extra radial load leading to one-sided biased loading; insufficient lubrication causing dry friction; uneven stress caused by tilted installation of two-piece washers; seal failure allowing foreign particles into raceways; permanent plastic deformation from overload exceeding basic static load; cage deformation induced by sustained impact loads. Shut down equipment immediately once accuracy degradation, abnormal noise or overheating appears. Bearings with permanent damage on raceways, balls or cage must be replaced as a whole.