Permanent Magnetic Lifters | SDM Magnetics Co., Ltd.

Ι What Are Magnetic Lifters?

Magnetic lifters, also called lifting magnets, use magnetic force to safely lift and move ferromagnetic materials such as steel plates, beams, and other heavy parts with flat or round surfaces. They can be powered by permanent magnets or electromagnets and allow handling without clamps, slings, or chains. Because of this, magnetic lifters are widely used in manufacturing, shipyards, warehouses, and construction for fast, efficient material handling.

Permanent magnetic lifters are especially popular because they have a compact structure, are easy to operate, and do not require any external power supply. By contrast, electromagnetic lifters often suffer from high power consumption, heat buildup, hysteresis effects, larger size, and frequent maintenance. These disadvantages make permanent magnetic lifters the preferred option in many industrial applications where efficiency, simplicity, and reliability are important.

Working Principle of Permanent Magnetic Lifters

The working principle of permanent magnetic lifters is based on the continuity and superposition of magnetic flux. Inside the lifter, the magnetic circuit is formed by a static permanent magnet group, a rotating permanent magnet group (rotor), and magnetic conductive parts such as the core and poles. These permanent magnets are usually made from high-energy Neodymium magnets.

By turning the handle, the operator rotates the moving magnet group, either adding its flux to the static group or diverting it inside the circuit to switch the lifter on or off.

In the “ON” position, the rotating and static magnet groups are aligned in the same direction, so their magnetic flux is superimposed and driven through the poles into the ferromagnetic workpiece, generating a strong holding force. In the “OFF” position, the two magnet groups are set in opposite directions, so most of the magnetic flux is closed inside the magnetic circuit and does not pass through the poles. This internal shunting of flux effectively cancels the external attraction and allows the workpiece to be released.

Specifications of Permanent Magnetic Lifters

Permanent magnetic lifters are available in a range of specifications to match different lifting tasks and industrial applications. Key parameters include rated lifting capacity, safety factor for magnetic force, minimum material thickness, and allowable operating temperature, among others.

The correct choice of permanent magnetic lifter depends on factors such as the type of material being handled, surface condition, operating environment, and required safety margin. Below is a detailed specification chart to help you compare options and select the most suitable model for your needs.

Model A

Model	Max. Lifting capacity (kg)		Max. Pull-off strength (kg)	Dimension (mm)				Operating temperature (℃)	Net weight (kg)
Model	Flat	Round	Max. Pull-off strength (kg)	W	L	H	R	Operating temperature (℃)	Net weight (kg)
100A	100	50	350	64	92	67	148	<80	3
300A	300	150	1050	80.6	162	90	226	<80	7.5
500A	500	250	1750	101	199.5	118	220	<80	20
600A	600	300	2100	101	232.5	118	224	<80	23
1000A	1000	500	3500	151	270	164	321	<80	55.5
2000A	2000	1000	7000	190	380	212	445	<80	125
3000A	3000	1500	10500	230.5	497	244	505	<80	220
5000A	5000	2500	17500	430	541	206	816	<80	395
6000A	6000	3000	21000	430	621	206	816	<80	440

Model C

Model	Max. Lifting capacity (kg)		Max. Pull-off strength (kg)	Dimension (mm)				Operating temperature (℃)	Net weight (kg)
Model	Flat	Round	Max. Pull-off strength (kg)	L	B	H	R	Operating temperature (℃)	Net weight (kg)
100C	100	50	350	64	92	67	121	<80	3
150C	150	75	525	64	125	67	110	<80	4.5
200C	200	100	700	80.6	140	90	205	<80	6
300C	300	150	1050	80.6	162	90	205	<80	7.5
500C	500	250	1750	101	199.5	118	226	<80	20
600C	600	300	2100	101	232.5	118	226	<80	23
1000C	1000	500	3500	151	270	164	264	<80	55.5
2000C	2000	1000	7000	190	380	212	370	<80	125
3000C	3000	1500	10500	230.5	497	244	500	<80	220

Model D

Model	Max. Lifting capacity (kg)		Max. Pull-off strength (kg)	Dimension (mm)				Operating temperature (℃)	Net weight (kg)
Model	Flat	Round	Max. Pull-off strength (kg)	W	L	H	R	Operating temperature (℃)	Net weight (kg)
100D	100	50	350	64	92	67	136	<80	3
200D	200	100	700	80.6	140	90	171	<80	7.5
300D	300	150	1050	80.6	162	90	171	<80	7.5
500D	500	250	1750	101	199.5	118	226	<80	23
600D	600	300	2100	101	232.5	118	226	<80	23
1000D	1000	500	3500	151	270	164	264	<80	65
2000D	2000	1000	7000	190	380	212	370	<80	145
3000D	3000	1500	10500	230.5	497	244	500	<80	255

Model E

Model	Max. Lifting capacity (kg)		Max. Pull-off strength (kg)	Dimension (mm)				Operating temperature (℃)	Net weight (kg)
Model	Flat	Round	Max. Pull-off strength (kg)	W	L	H	R	Operating temperature (℃)	Net weight (kg)
100E	100	50	350	60	114	74	136	<80	3.5
125E	125	50	438	60	114	74	136		3.5
150E	150	75	525	60	147	70	136	<80	5
200E	200	100	700	80	146	85	136	<80	6
300E	300	150	1050	80	186	91	136	<80	10
500E	500	250	1750	100	230	110	150	<80	16
1000E	1000	500	3500	176	305	165	285	<80	58
2000E	2000	1000	7000	200	400	210	335	<80	117
3000E	3000	1500	10500	230	525	246	580	<80	220

Model H

Model	Max. Lifting capacity (kg)		Max. Pull-off strength (kg)	Dimension (mm)				Operating temperature (℃)	Net weight (kg)
Model	Flat	Round	Max. Pull-off strength (kg)	W	L	H	R	Operating temperature (℃)	Net weight (kg)
100H	100	50	350	75	90	50	148	<80	4
200H	200	100	700	110	125	55	148	<80	6.5
300H	300	150	1050	132	162	60	180	<80	9.5
600H	600	300	2100	163	233	74	185	<80	23
1000H	1000	500	3500	190	300	85	210	<80	58

Key Considerations for Permanent Magnetic Lifters

When using permanent magnetic lifters, several factors must be considered to ensure safe and efficient operation. The actual lifting capacity depends on the thickness, material type, and surface quality of the load. For best performance, the workpiece should have sufficient thickness; thin plates reduce magnetic flux and weaken the lifting force.

Surface condition is equally important. Rough, rusty, painted, or dirty surfaces can significantly lower the effective lifting capacity. Ideally, the surface roughness (Ra) should be less than 6.3 μm for reliable results. Always follow the rated lifting capacity of the permanent magnetic lifter, which is usually based on ideal test conditions, such as mild steel with a thickness of around 60 mm, and reduce the allowable load if your conditions are less than ideal.

Key Considerations for Permanent Magnetic Lifters

Before lifting, carry out a risk assessment that considers the workpiece’s center of gravity, balance, and environmental factors such as temperature. Regular inspection and maintenance of the lifter are also essential to ensure long-term safety and dependable performance in industrial applications.

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