THK BL12BD Link Ball | THK BL12BD Distributor

More about: THK BL12BD Link Ball | THK BL12BD Distributor

Note: Model BL-A is only available in size 4 and 5.
For more detailed specifications, please download the Product Catalog with the link in the Downloads section of this product page.

Model No.	Outer dimensions			Threaded S1 JIS Class 2	Holder dimensions						Ball shank dimensions						Ball diameter Da	Permissible tilt angles 2θ°	Applied static load Cs	Yield point strength Pk	Mass
	Length L	Diameter D	Height M		L1	l	L2	D1	D2	W 0 -0.3	d2 h9	M1	M2 ±0.3	l1	Hexagon B 0 -0.3	d4
																						mm	mm	mm	mm	mm	mm	mm	mm	mm	mm	mm	mm	mm	mm	mm	mm	degree	N	N	g
	BL4DA	24.5	13		20	M4×0.7	18	8	4	7.5	9.5	8	4	15	7	6	7	8.1	7.938	40	4510	1370	7
BL5DA	34.5	15	26.7	M5×0.8	27	15	4	9	12	10	5	21	10	8	8	9.2	9.525	40	6470	2250	12
BL6D	38	16	32.6	M6×1	30	16	5	10	13	11	6	26	11	11	10	11.6	11.112	40	9900	3920	26
BL8D	45.5	19	38.6	M8×1.25	36	19	6	12.5	16	14	8	31	14	12	12	13.8	12.7	40	12500	6570	49
BL10D	55.5	25	46.3	M10×1.25	43	23	7	14.5	19	17	10	37	17	15	14	16.2	15.875	40	18300	11300	87
BL10BD	55.5	25	52.3	M10×1.5	43	23	7	14.5	19	17	10	43	17	21	14	16.2	15.875	40	18300	11300	90
BL12D	64.5	29	52.7	M12×1.25	50	26	8	17.5	22	19	12	42	19	17	17	19.6	19.05	40	26700	16400	143
BL12BD	64.5	29	59.7	M12×1.75	50	26	8	17.5	22	19	12	49	19	24	17	19.6	19.05	40	26700	16400	148
BL14D	74	34	68.4	M14×1.5	57	30	10	20	25	22	14	56	21.5	22	19	21.9	22.225	40	36400	19800	235
BL14BD	74	34	74.4	M14×2	57	30	10	20	25	22	14	62	21.5	28	19	21.9	22.225	40	36400	19800	245
BL16D	83	38	74	M16×1.5	64	34	11	22	27	24	16	60	23.5	23	22	25.4	22.225	30	36400	26900	315
BL16BD	83	38	80	M16×2	64	34	11	22	27	24	16	66	23.5	29	22	25.4	22.225	30	36400	26900	325

Application of THK THK BL12BD

THK BL12BD is a radial-direction Link Ball designed for articulated mechanical connections where angular movement and reliable load transmission are required. It features an M12 × 1.75 male thread, a 19.05 mm ball diameter, and a 40° permissible tilt angle, making it suitable for mechanical linkage systems that require a robust spherical connection.

Machine Tools and Mechanical Linkages

THK BL12BD can be used in mechanical linkage assemblies around machine tools and industrial machinery. The spherical ball structure allows connected components to accommodate angular movement while maintaining a compact mechanical connection.

Typical applications include linkage mechanisms, adjustment systems, actuator connections, lever mechanisms, and other articulated components where alignment between connected parts may change during operation.

Automation and Actuation Systems

In automated machinery, Link Balls can connect actuators, rods, levers, brackets, and other moving components. The spherical joint allows the connected components to move through an angle without requiring rigid alignment throughout the complete operating cycle.

The BL12BD is suitable for applications where an M12 × 1.75 threaded connection is required together with a relatively large spherical ball and high static load capacity.

Mechanical Control and Transmission Mechanisms

The BL12BD can be applied to mechanical control systems where movement must be transmitted between components through an articulated connection.

Possible applications include control linkages, mechanical transmission mechanisms, position-adjustment systems, and lever-operated equipment. Its radial-direction design is appropriate for applications where the main load is applied around the spherical joint.

Automotive and Transportation Equipment

THK Link Balls can be used in automotive-related linkage mechanisms requiring compact articulated connections. They allow connected rods and components to accommodate angular movement while maintaining a compact mechanical structure.

The BL12BD can be considered for applications where the M12 × 1.75 thread size and higher load capacity are suitable for the mechanical design.

Industrial Equipment and Heavy-Duty Linkages

With an applied static load of 26,700 N and a yield point strength of 16,400 N, the THK BL12BD is suitable for mechanical linkage applications requiring a relatively high-strength spherical connection.

It can be used in industrial machinery, actuator linkages, control mechanisms, and other equipment where reliable angular movement and mechanical load transmission are required.

BL12BD Thread Selection

The main difference between the BL12BD and BL12D is the thread specification.

Model Thread Ball Diameter Permissible Tilt Angle Applied Static Load Yield Point Strength Mass
THK  BL12D    M12 × 1.25    19.05 mm   40° 26,700 N    16,400 N   143 g
THK  BL12BD M12 × 1.75    19.05 mm   40° 26,700 N    16,400 N   148 g

When replacing an existing Link Ball, the thread pitch should be checked carefully. Although BL12D and BL12BD have the same ball diameter and load specifications, their thread pitches are different and they should not be treated as directly interchangeable without checking the mating component.

Selection Considerations for THK BL12BD

Before selecting BL12BD, check the following operating conditions:

Required radial load
M12 × 1.75 thread compatibility
Required angular movement
Available installation space
Direction and magnitude of the applied load
Operating frequency and movement conditions
Lubrication requirements
Environmental conditions
Required service life

For applications involving continuous oscillation, impact loads, or significant vibration, the actual operating conditions should be evaluated against the manufacturer’s specifications before final selection.