What are the differences between single-row and double-row deep groove ball bearings in structure and application

As one of the most commonly used types of rolling bearings, deep groove ball bearings are widely used in various types of mechanical equipment due to their simple structure, low friction and long service life. According to the arrangement of rolling elements, deep groove ball bearings can be divided into two types: single-row deep groove ball bearings and double-row deep groove ball bearings. There are significant differences between the two in terms of structural form, load-bearing capacity, axial space occupation, and applicable scenarios.

Structural differences
Single-row deep groove ball bearings contain only one row of rolling elements, usually consisting of an inner ring, an outer ring, a row of steel balls and a cage. The steel balls run in the deep groove groove and can withstand both radial loads and axial loads to a certain extent.
Double-row deep groove ball bearings are structurally equivalent to combining two single-row deep groove ball bearings side by side into one, containing two rows of rolling elements. The inner and outer rings of double-row bearings are optimized and are generally integral structures to improve installation coaxiality and operating stability.
Due to the addition of a row of steel balls, the overall size of the double-row bearing is slightly larger, especially significantly increased in the width direction. In addition, double-row bearings have higher requirements for manufacturing tolerances and groove symmetry to ensure their dynamic balance performance under high load.

Load capacity comparison
Single-row deep groove ball bearings are suitable for medium load conditions, can withstand high radial loads, and can withstand unidirectional or bidirectional axial loads at medium and low speeds. However, due to only one row of steel balls, their total load capacity is relatively limited, especially under large axial force or impact load conditions, fatigue failure is prone to occur.
Due to the two rows of rolling elements, the rated load capacity of double-row deep groove ball bearings is much higher than that of single-row structures of the same size. Especially under the combined load conditions of radial and axial loads, the double-row structure can better share the load and reduce the deformation of the inner or outer ring, thereby improving the overall life and operating stability.

Space utilization and installation requirements
In the design and selection of bearings, space utilization is a key consideration. Single-row deep groove ball bearings have a compact structure and a small width, which are very suitable for equipment with limited installation space or occasions requiring lightweight design. Its installation method is flexible, and it can be quickly assembled through sleeves, interference fits, etc., and it is easier to achieve quick replacement.
Double-row deep groove ball bearings occupy more axial space due to the increased structural width. This may bring installation restrictions to equipment with compact structure or limited length. In addition, the double-row structure requires higher installation accuracy. Once the installation deviation is large, it may cause uneven force on the two rows of steel balls, thereby shortening the bearing life. Therefore, special attention should be paid to the coaxiality of the bearing seat hole and the matching accuracy of the shaft neck when using it.

Differences in application scenarios
Single-row deep groove ball bearings are widely used in conventional mechanical equipment such as motors, automobiles, household appliances, and industrial gearboxes due to their strong versatility and low cost. They are suitable for working conditions with high speed and medium load. Its excellent low friction performance makes it particularly suitable for occasions requiring low noise and smooth operation, such as fans, power tools, office equipment, etc.
Double-row deep groove ball bearings are more commonly used in equipment with large loads and high load-bearing performance requirements, such as heavy gearboxes, winches, metallurgical equipment, elevator motors, large industrial fans, etc. It is also commonly used in transportation machinery and agricultural machinery. Especially in working conditions where the structural space is sufficient but the load fluctuates violently, double-row bearings can provide higher reliability.