ZnS medium consistency screen is a modern international advanced pulp screening equipment. It is a new generation of pulp medium consistency screening equipment developed by our company by absorbing international advanced technology.It is suitable for heat screening of wood pulp or straw pulp;Coarse or fine screening of chemical pulp and waste paper pulp;Compared with the general low consistency pressure screen, the medium consistency pressure screen has the characteristics of strong adaptability, energy saving, water saving and high production efficiency.

Structure principle of medium consistency screen:

The pressure screen is composed of body, cover, screen drum, rotary cylinder, base and transmission part.Stainless steel materials are used for the parts contacting with the slurry.

The pressure screen is a vertical structure with a cylindrical shell. The top of the shell is equipped with a removable top cover. All necessary connecting pipe flanges are installed on the shell. The screen body and motor frame are fixed on the base by bolts. A round screen drum is installed in the shell. A rotor and bearing are installed in the screen drum. The main shaft of the screen is sealed by mechanical seal.

The pipe end bracket is set at the closest place of the frame.Connect seal water and bearing lubrication with seal and bearing respectively.

1.Shell part

The main body of the machine is welded with stainless steel plate. There is an annular seat inside to install the screen drum and the drive bearing. It is installed on the bottom plate of the shell. There is a slurry inlet pipe in tangent direction at the upper part, a good slurry outlet pipe at the lower part, a slag discharge pipe and a dilution pipe at the bottom. The whole shell is fixed on the base with bolts.

2.cover

The top cover is a stainless steel plate spherical head, which is connected with the shell by bolts, and the central part is equipped with a valve joint to discharge the residual gas and possible light impurities in the machine.

3.Sieve drum

The screen drum has two structural forms: plate wave screen drum and rod wave screen drum.

The sieve plate of plate wave sieve drum is made of stainless steel plate and has two kinds of hole type and seam type.A corrugated groove is arranged on the surface of the sieve plate which is in contact with the pulp. Its function is to make the fiber easy to pass through the sieve hole (seam), and effectively separate the qualified fiber from the impurities and fiber groups, so as to improve the screening efficiency and obtain high-quality pulp.The screen plate is drilled or milled, and the surface is polished. The surface of the screen drum is smooth, and the outer surface of the screen drum is welded with a reinforcing ring, so that the screen drum has enough strength and rigidity;The upper end face is provided with a flange, which is fixed on the cylinder body with bolts, and the lower end is located in the cylinder body, so the combination is firm and the operation is stable.

The structure of the bar wave screen drum is composed of hundreds of special wedge-shaped bars, which are evenly embedded in the groove on the circumference of the multi-layer annular plate along the circumferential direction. The upper end is a flange surface, which is connected with the cylinder, and the lower end is a cone. The surface of the screen drum is wavy. The screen seam can be more refined than the plate milling seam structure, with higher precision, significantly higher opening rate, and greatly improved bar strength than the milling seam screen plate,Especially after the surface hardening treatment, the service life of the screen drum is longer, which is an advanced structure in the world.

4.Gyratory drum

The rotary drum is a cylinder with a number of reasonably arranged bumps on its outer surface.High frequency pulse is generated when rotating at high speed to screen slurry and purify screen hole.

The seal of rotor shaft adopts mechanical seal. In order to prevent slurry leakage or entering the transmission room, the machine is equipped with mechanical seal and seal water pipe interface. The water pressure is required to be about 0.1MPa higher than the slurry inlet pressure.

5.Driving device

The rotor shaft is supported on the bearing pedestal and driven by the motor through a set of narrow V-belts.The lubrication device is installed on the base of the frame to lubricate the bearing regularly.

Advantages of medium consistency sieve:

1.Multi wing block design, no winding, mild pulse, clean screen pulp, high pulse frequency and large capacity.

2.Medium concentration screening (max. 4%) can reduce water consumption in production process, with obvious energy-saving effect, small screen drum area of the same capacity, low investment and maintenance cost.

3.The screening area has less thickening, high screening efficiency and long service life of screening drum.

4.Equipped with automatic oil filling device and mechanical seal water flow monitoring device, reserved DCS interface (bearing temperature rise, vibration detection), high degree of automation.

Technical parameters of medium consistency screen: