Product Introduction

240 Series Spherical Roller Bearings are wide‑section double‑row spherical Roller Bearings for large bore sizes, belonging to large‑bore heavy‑duty widened family together with 241 series. Spherical outer‑ring raceway and double‑row barrel‑shaped rollers offer 1.0‑1.5° self‑aligning compensation for large‑shaft deflection and assembly misalignment. It delivers high radial load capacity, considerable bidirectional axial load and good shock resistance.

Its width is larger than 231 while smaller than 241, with relatively low limiting speed. Straight‑bore and 1:12 tapered‑bore K types are available; most sizes are equipped with W33 grease groove and holes. Precision grades P0 and P6. Mainly used for heavy‑duty machinery with large shaft diameter, high‑load requirement, allowable wide axial mounting dimension and low‑speed demand.

Brief comparison: 231 medium‑width; 232 widened; 240 large‑bore wide‑section; 241 further widened with higher load and lower speed. Suitable for large‑shaft‑diameter applications with sufficient axial space, heavy‑load priority and low‑speed requirement.

Specifications

Bore range:200‑700mm (model range 24040‑240/700). Versus 231 of identical bore, load capacity rises by 20‑32%, width increases significantly and limiting speed drops 12‑22%.

Reference Model:24048CA/W33

‑ Bore d:240mm

‑ Outer diameter D:360mm

‑ Width B:118mm

‑ Basic dynamic load Cr:1060kN

‑ Basic static load Cor:1420kN

‑ Limiting speed(grease):900r/min

‑ Limiting speed(oil):1100r/min

Withdrawal sleeves are preferred for large‑bore tapered‑bore variants. Closely monitor clearance reduction in assembly to avoid over‑preload.

Material, Model & Suffix Explanation

Inner / outer rings and rolling elements adopt vacuum‑degassed or electroslag‑remelted GCr15 bearing steel, quenched‑tempered hardness HRC 58‑62.

Cage:

‑ CA solid brass cage, standard for heavy‑duty large sizes;

‑ CC stamped‑steel cage is seldom used for this series;

‑ E/E1 optimized roller profile for higher load rating.

Suffixes

‑ K:1:12 tapered bore;

‑ W33: outer‑ring grease groove & lubrication holes;

‑ C2/C3/C4 radial clearance; C3 general‑purpose, C4 for shock‑vibration.

Typical model: 24048CAK/W33C3: 240 series, solid brass cage, tapered bore, W33 grease groove, C3 clearance.

Manufacturing Process

1. Ultrasonic raw‑material inspection for inclusion and porosity defects of large forgings;

2. Hot die forging for continuous metal flow‑lines of wide‑section raceway;

3. Staged controlled quenching‑tempering to reduce warpage distortion of wide large rings;

4. Turning with strict geometric‑tolerance control for ribs and raceways;

5. Superfinishing for rollers and raceways to optimize contact profile and reduce stress concentration;

6. High‑precision clearance grouping‑matching and thorough W33‑groove deburring;

7. Finished‑product non‑destructive inspection, dimension‑clearance‑vibration test, multi‑point‑support cleaning and anti‑rust packaging.

Application Scenarios

Heavy‑duty equipment with large shaft diameter, sufficient axial installation space, heavy load, moderate shock and low‑speed requirement.

‑ Metallurgy: large roller tables, rotary mechanisms

‑ Building‑material: large rotary kilns, dryers

‑ Mining: large rotary drums, ball mills

‑ Heavy machinery: low‑speed heavy‑duty gearboxes

W33 for on‑site re‑lubrication maintenance; upgrade to 241 for higher load capacity; switch to 231 / 232 for higher‑speed requirement.

Installation Guidelines

1. Max thermal‑mount heating ≤110 ℃. Ensure uniform temperature for large rings. Open‑flame heating forbidden. Strike only bearing end faces.

2. Tighten withdrawal sleeve step‑by‑step in multiple passes for tapered‑bore bearings, re‑measure clearance after each tightening pass.

3. Appropriately increase mounting interference under shock‑load conditions to prevent slipping damage.

4. Precisely align W33 grease groove with housing lubrication passages.

5. Manually rotate shaft after assembly; perform no‑load running‑in. Full‑load operation is allowed only after normal temperature rise is confirmed.

After‑sales Maintenance

1. Lubrication: heavy‑duty extreme‑pressure lithium grease, fill 1/3‑2/3 of cavity. Periodically re‑grease to expel aged grease. Over‑filling‑caused overheating is prohibited.

2. Inspection: temperature rise ≤+40 ℃ above ambient. Shut‑down immediately upon abnormal noise or sharp temperature rise.

3. Storage: large‑size bearings stored horizontally with multi‑point support. Vertical storage is strictly forbidden. Keep moisture‑proof and rust‑proof.

4. Failure diagnosis: raceway spalling from overload; rib wear due to excessive axial force; abrasive wear caused by seal failure; cage damage induced by improper mounting.

Selection Notes

240 features large‑bore wide‑section for high load capacity. Choose 241 for further higher load; choose 231 / 232 for higher‑speed priority. Add thrust bearings under heavy axial load. Apply reliable sealing under harsh working environment.