Three-legged centrifuge structure, working principle, operation method

Machines that use the inertial centrifugal force generated by the rotation of the machine to separate or concentrate suspensions, emulsions, and other heterogeneous systems are called centrifuges.

Centrifuges are divided into filter centrifuges, sedimentation centrifuges, and separation centrifuges according to the operating principle.

The inner wall of the rotating drum of the filter centrifuge is covered with filter media woven from the filter cloth and the wire mesh, and many holes are opened on the rotating wall. The suspended capture liquid in the rotating drum rotates together with the rotating drum. Under the effect of centrifugal force, the liquid passes through the filter medium and the holes in the drum wall and is thrown out of the rotating drum. The solid particles are trapped on the surface of the filter medium to form a filter residue layer. The separation of solid particles and liquid.

Filter centrifuges have a variety of structural types today because of differences in support methods, discharge methods, and operating force methods. Intermittent filter centrifuges include three-legged centrifuges, upper suspension centrifuges, horizontal scraper discharge centrifuges, and bag-turning discharge centrifuges; successive filter centrifuges have piston push centrifuges, centrifugal discharge centrifuges, Spiral discharge centrifuge, precession discharge centrifuge, oscillating discharge centrifuge. The following only introduces the commonly used three-legged centrifuge:

1. Structure

The three-legged centrifuge is a centrifuge widely used in pharmaceutical factories. According to the discharge method, there are manual upper discharge, suction upper discharge, hanging bag upper discharge, manual lower discharge, scraper lower discharge and flip discharge. Commonly used is the upper unloading, whose structure is mainly composed of components such as column foot, chassis, main shaft, casing and rotating drum. The entire chassis is suspended on the spherical supports of the three literature schools by a tension spring, and can swing freely in the direction of horizontal force, which is beneficial to slow down the oscillation caused by the uneven distribution of materials.

2. working principle

In a general situation, when separating the suspension, the material liquid will gradually participate in the rotating drum after the centrifuge is started; when the separating paste-like materials or pieces are dried, the materials should be included in the rotating drum before the centrifuge is started, and Ensure that the materials are evenly distributed around.

The advantages of the three-foot centrifuge are: simple structure, stable operation, filter residue can be washed, and the filter residue is low in liquid. Filtration time can be sensitively controlled according to the liquid content of the filter residue, so it is widely used for separating small batches and various materials. The disadvantage is that the transmission organization and the brake are in the lower part of the fuselage, which is susceptible to corrosion.

3 operations

(1) Before power-on operation, the following items should be checked:

① Loosen the brake handle and roll the drum by hand to see if there is a bite or jam;

② Roll the drum by hand and pull the brake handle to see if the brake is sensitive and firm;

③ Whether the connecting bolts of the motor part are tight, adjust the triangle belt to the proper tightness;

④Check if the anchor bolts are loose.

(2) Only after the inspection is normal, can it be powered on and run empty. The rotation direction of the drum must be in accordance with the direction on the direction sign (from the top to the bottom, it is necessary to rotate clockwise), and it is prohibited to run in the opposite direction.

(3) Put the materials into the drum as evenly as possible, the amount of the loaded materials should not exceed the maximum loading limit of various specifications and ratings.

(4) After the dehydration is completed, the power supply should be blocked first, and the brake handle should be operated slowly to brake slowly, generally within 30 seconds. Do not brake hard to avoid damage to the machine parts. Do not touch the drum with the hand when the drum is fully stopped.