THK BL12D Link Ball | THK BL12D Distributor

More about: THK BL12D Link Ball | THK BL12D 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 BL12D

THK BL12D is a radial-direction Link Ball designed for articulated mechanical connections where a compact spherical joint is required to accommodate angular movement. With an M12 × 1.25 male thread, 19.05 mm ball diameter, and 40° permissible tilt angle, the BL12D is suitable for mechanisms that require both mechanical strength and smooth angular movement.

Machine Tools and Mechanical Linkages

THK BL12D can be used in mechanical linkage mechanisms of machine tools where components need to transmit movement while allowing angular adjustment. Its spherical ball structure helps accommodate changes in alignment between connected components.

Typical applications include linkage assemblies, adjustment mechanisms, actuator connections, and mechanically articulated components around machine tools.

Automation and Actuation Mechanisms

In automated equipment, Link Balls can be installed between actuators, levers, rods, and other moving components. The spherical joint allows the connected parts to move through an angle without requiring perfect alignment throughout the entire operating cycle.

BL12D is particularly suitable for applications where a larger threaded connection and higher load capacity are required compared with smaller BL models.

Control and Mechanical Transmission Systems

The BL12D can be used in mechanical control and transmission mechanisms where movement from one component must be transferred to another through an articulated connection.

Applications may include control linkages, lever mechanisms, position-adjustment systems, and mechanical transmission assemblies. The radial-direction design is suitable for applications where the primary load is supported around the spherical joint.

Automotive and Transportation Equipment

THK Link Balls are also used in automotive-related linkage mechanisms, including systems requiring compact articulated connections. Link Balls can accommodate angular movement between connected rods and brackets while maintaining a compact mechanical structure.

The BL12D can be considered for applications where the M12 threaded connection and higher load capacity are appropriate for the mechanical design.

Heavy-Duty Mechanical Linkages

With an applied static load of 26,700 N and a yield point strength of 16,400 N, THK BL12D is designed for applications requiring a relatively high-strength Link Ball connection.

It can be used in industrial machinery, mechanical control systems, and other equipment where a robust articulated connection is required.

Selection Considerations for BL12D

When selecting THK BL12D, the following factors should be checked:

Required radial load and operating load
Available installation space
M12 × 1.25 thread compatibility
Required angular movement
Direction of the applied load
Operating speed and movement frequency
Lubrication and environmental conditions
Required service life and maintenance requirements

For applications involving continuous movement, shock loads, or significant vibration, the actual operating conditions should be evaluated against the allowable load and movement requirements before selecting the Link Ball.

THK BL12D Compared with Other BL Series Models
Model Thread Ball Diameter Permissible Tilt Angle Applied Static Load Mass
THK BL10D   M10 × 1.25     15.875 mm   40°   18,300 N    87 g
THK BL12D   M12 × 1.25    19.05 mm     40°   26,700 N   143 g
THK BL12BD   M12 × 1.75  19.05 mm   40°   26,700 N   148 g
THK BL14D   M14 × 1.5    22.225 mm   40°   36,400 N   235 g

The THK BL12D uses an M12 × 1.25 thread and a 19.05 mm spherical ball. Compared with the smaller BL10D, it provides a larger ball size and higher applied static load. The BL12BD has the same ball diameter and load rating as the BL12D but uses an M12 × 1.75 thread.