Solid Shaft Ferrofluidic Feedthrough Magnetic Fluid Seal

Solid Shaft Magnetic Fluid Seal Flange Mount FerroSeals Double Ended Bearing Type

A ferrofluid has the fluid properties of a liquid and the magnetic properties of a solid. The ferrofluids actually containtiny particles(around 10nm diameter) of a magnetic solid suspended in a liquid medium. To keep them small,magnetic and van der waals interactions must be overcome to prevent the particles from agglomerating. Thermal motion of magnetite particles smaller than 10nm in diameter is suffcient to prevent agglomeration due to magnetic interactions.

The principle of Magnetic sealing

A ferrofluid style rotary seal vacuum feedthrough uses the response of a magnetic fluid with an applied magnetic field. Rotary seal components include a ferrofluid, permanent magnet, two pole pieces and a magnetically permeable shaft. The magnetic circuit employs stationary pole pieces and the rotating shaft to concentrate the magnetic flux in the radial gap under each pole piece. When the ferrofluid is applied to this radial gap, it takes the shape of a liquid O-ring and produces a hermetic vacuum seal. Ferrofluidic vacuum rotary seal feedthroughs use fabricated multiple rings or grooves with ferrofluid locating in stages formed by grooves machined into either the shaft or pole pieces. Typically each single stage or groove can sustain a pressure differential of 0.2 atmospheres (200 mbar). The total vacuum pressure achieved is the sum of all the differential pressures provided by the grooves.

DRACHMA (ZHANGJIAGANG) MATERIAL CO.LTD has two main production plants. Zhangjiagang plant is responsible for the rough forming of workpieces, mainly forging process; While Hangzhou plant is mainly responsible for precision machining, welding and inspection of products. We implement this layout mainly to use the industrial advantages of each region to achieve maximum economic benefits.

Traditional processing enterprises often do not have such ability, the lack of blank forming ability is unable to achieve the optimal use of materials, resulting in excessive processing allowance, long cycle, high cost. Zhangjiagang is located in the southern jiangsu province, which has the strongest forging capacity in China. It has a good supporting industry and can realize the diversified production of forging and pressing blanks. Thanks to this, the product cycle of our company is faster, the cost performance is higher, and the forging products have better mechanical properties than the products directly processed by rod or plate.

In addition, our company has strong welding ability, which can weld and assemble parts to achieve system delivery. We adopt the mode of automatic robot welding and manual precision welding to achieve flexibility and high quality.

Stainless steel :304/1.4307 316/1.4404 321/1.4541 316Ti/1.4571 317L 904L F44 NO6625 UNS718

440A/B/C 431 446 F6a 

Carbon Steel:A105, SA350 LF1, LF2, LF3, LF6, A707, A694, 4130, 4140, 8620, 8630, A182F5, F11, F12, F22, F91, F92

Duplex steel : F51 F60 F53 F55

Alloy Steel:4130, 4140, 4142, 4145, 4150, 4320, 4330, 4340, 4350, 4620, 4820, 6150, 8620, 8630, 8822, 9310, 52100, HY80, HY100, 9315, 300M, Nitralloy 135M, 17-22A

Aluminum : 2014, 2024, 2025, 2219, 2618, 3003, 5083, 6061, 7049, 7050, 7075, 7079, 7149, 7150, and 7175