Cheap round lifting electromagnet

A cheap round lifting electromagnet is not a marketing slogan, but a real solution for workshops, warehouses and construction sites, where every minute of downtime costs money. We saw how crews at the Yekaterinburg plant replaced a hydraulic gripper withcheap round lifting electromagnet— installation took 18 minutes, and the load change increased by 22%. No pipes, no oil pumps, no leaks - just power cable and steel.

Why “round” is not a shape, but the physics of work

The round design is not a tribute to aesthetics. It gives a uniform distribution of magnetic flux over the entire surface. In rectangular or oval models, “weak zones” appear along the edges: when lifting a 6 mm thick sheet, a piece weighing 35 kg can come off in the corner. The round one works like a single magnetic disk. We tested this on samples of LONGI LJM-RC series: at a voltage of 220 V and a temperature of +45 °C, the retention coefficient (F_beat/m) amounted to 12.8 kN/kg - higher than the GOST R standard by 19%.

Important: “cheap round lifting magnet” does not mean a compromise in safety. Models with a diameter of 200–350 mm have double winding insulation (class H), overheat protection by a thermal sensor and emergency shutdown when the voltage drops below 185 V. This is not a “budget option” - it is an optimized engineering choice.

Quick installation - when “quick” means “without extras.” fasteners"

We observed three common installation errors:

• Welding the bracket to the body - leads to deformation of the magnetic circuit and a reduction in holding force by 30–40%
• Using M12 bolts instead of the recommended M16 - due to vibration, the fasteners weaken after just 2 shifts
• Connection without a voltage control relay - winding overload when the network drops to 198 V causes overheating in 7 minutes

The solution is ready-made LONGI mounting kits: a flange with pre-installed holes for M16, a built-in temperature sensor and an IP67 type connector. We connect - we check - we work. At one enterprise in Novosibirsk, 12 units were installed per shift without the involvement of a welder. The connection diagram is on the website ljmagnet.ru, section “Technical documentation”.

Reliable retention is not about “maximum on paper”, but about real conditions

The declared lifting force of 1500 kg is a figure for an ideal case: pure St3 steel, thickness 20 mm, surface without rust or paint, temperature +20 °C. In practice, everything is different. We carried out tests with recycled metal workpieces: rust up to 0.3 mm, traces of oil, surface roughness up to 0.8 mm. Result: LJM-RC300 models held 920 kg - not 1500, but stable, without slipping. Why? Because they have an increased air gap in the magnetic circuit (up to 1.2 mm) and a reinforced Fe-Co-V alloy core.

If your task is to lift scrap, stampings or steel plates from the workshop floor, choose a model with a strength reserve of at least 40%. Don't skimp on this. A cheap round lifting electromagnet should be designed not to “lift something,” but to “lift something every day without failure.”

LONGI Corporation: not a manufacturer, but an operating partner

Shenyang Longji Scientific Electromagnetic Co., Ltd. was founded in 1993. Today there are 1,200 people, more than 60% with higher technical education, our own testing laboratory and 4,000 pieces of equipment per year. But something else is more important for us: we know how an electromagnet breaks down in the Ural cold, how the winding behaves during frequent cycles in a wet workshop, and why the service life decreases when used in conjunction with a low-quality rectifier.

Therefore, all LJM-RC models undergo 72-hour stress testing: 500 on/off cycles, heating to +85 °C, cooling to –30 °C, vibration 5-500 Hz. And only after this they receive a certificate of conformity TR CU 010/2011. Cheap round lifting electromagnet from LONGI is the price you pay once. And not the one that pops up in the form of downtime, repairs and loss of cargo.