SU816665A1 - Unit for removing non-magnetic inclusions from moulding sand - Google Patents

Description

one

The invention relates to foundry, in particular, equipment for the separation of bulk materials, namely the removal of non-magnetic metallic inclusions from the circulating molding mixture in the production of castings.

A known apparatus for removing non-magnetic metallic inclusions from the circulating molding sand, in which the components are separated from each other by air flow.

The installation consists of chambers of separation and sedimentation, separated by a fixed partition of constant height, an air collector, systems for waste disposal and transportation of sand 1.

However, when the humidity of the circulating molding sand changes, the known installation does not provide reliable separation of sand and metallic inclusions. Depending on the conditions of manufacture of the castings, the moisture content of the circulating molding sand is usually not more than 4.5%. When the moisture content of the mixture is 2.5-4.5 / o, the separation of metallic inclusions and sand is difficult, since a significant part of the sand in the form of lumps is removed with metallic inclusions. When the moisture content of the circulating mixture is less than 1.5%, metal inclusions with a size of less than 3 mm are removed from the installation along with the sand.

The purpose of the invention is to increase the efficiency of separation of non-magnetic metallic inclusions from recycled molding sand, which has different humidity and in increasing the safety of work in the manufacture of sand molds.

О The goal is achieved due to the fact that a shield is installed between the separation and sand deposition chambers in the installation to rotate in the direction of the deposition chamber and horizontal edges are aligned on the working surface of the shield from the separation chamber side, and the height of the ribs is 0.25-0.45 their distances from the axis of rotation of the flap.

The drawing shows a diagram of an installation for removing non-magnetic metallic inclusions from circulating molding sand.

The proposed installation consists of a transporting system 1 for feeding circulating molding sand 2 for separating separation chamber 3, air manifold 4 for supplying air flow 5, sand settling chamber 6, chute 7 and waste disposal system 8, sand chilling 9, sand transporting system 10 , swivel sh, itka Pi nozzle 12 to remove the exhaust air. The proposed installation works in the following way. Through the transport system 1, the circulating mixture 2 enters the chamber 3 for separation. .... v. „V..j..c .. ..c., .., m ..,. .. with .., .... Due to the air flow 5 entering from the collector 4, sand is transferred through the flap 11 into the deposition chamber 6, and then through the drain 9 enters the system 10 for transportation to the mixing and preparation compartment. Waste non-magnetic metallic inclusions flow into system 8 to collect and remove recycled molding mixture 2 from the separation section 2. Exhaust air, together with the dust-like fraction, is removed through a pipe 12 by means of a ventilated air, while air is cleaned from dust before discharging in atmosphere. With a backwash of 2.5-4.5% moisture, the flap 11 is placed in a vertical position. However, when the threshold is high (when the shield is installed And to the extreme vertical position) metal particles cannot get into the precipitation chamber 6 together with the sand. Moreover, the ribs on the flap 11 do not allow the metal inclusions to slide along its surface and this delays them in the separation chamber 3. When the moisture content of the working mixture 2 is less than 1.5%, there are no lumps of the mixture, and the mixture itself practically consists of separate grains of sand. In order to separate the metallic inclusions, a large movement of the mixture is not required and the flap 11 is turned to the lowest position. The pressure of the air flow 5 in the manifold 4 is reduced and the path of movement of the sand is reduced (for € th) the height of the threshold is reduced. In this case, metal particles can not be moved through the threshold. When the humidity of the working mixture of 1.5-2.5% of the rotary flap 11 is set to an intermediate position. The advantage of the proposed installation in comparison with the existing ones is that it is equipped with a rotary shield // - installed between the separation chambers 3 and the deposition chamber 6, which adjusts the height of the threshold depending on the humidity change of the mixture 2 entering the installation. In connection with this, the metal particles cannot get into the precipitation chamber 6 with sand, and the lumps of the wet mixture 2 do not enter the waste. The ribs on the flap 11 not only improve the quality of separation of the working mixture, but also reduce the abrasive wear of the working hardness of the flap 11, since movement of the abrasive particles along its surface is precluded. The ribs on the shield have a different height, which is chosen based on the following. The surface of the flap is not uniformly affected by the abrasive air-sand flow. To a greater extent, this effect tests the surface of the shield, the furthest from the axis of rotation, to a lesser extent, the surface located near the axis with a slight deflection of the shield from the vertical position of the edge, which contributes to the deflection of sand between them and leads to self-lining of the shield surface. Due to the uneven effect of the flow on the surface of the flap, the height of the ribs is different and is 0.25 - 0.45 distance from the axis of rotation. When the rib height is more than 0.45, the separation of the molding sand is quite effective, but the installation performance decreases. When the rib height is less than 0.25 the distance from the axis of rotation, the wear of the shield and the ribs themselves are intense, which leads to a significant reduction in the service life of the installation. By improving the quality of separation and simultaneously cooling the circulating molding sand, the quality of castings from austenitic steels such as high-manganese and chromonic improves the formula of the apparatus for removing non-magnetic metallic inclusions from the molding sand containing chambers of separation and sedimentation of sand, heat and air collector the fact that, in order to increase the efficiency of separation, and to improve the safe working conditions, the installation is equipped with a swivel shield installed between measures the separation and deposition of sand pivotable toward the deposition chamber, and the horizontal ribs are formed on the operating panel by the superficial separation chamber, wherein the height of the ribs is equal to 0.25-0.45 of the distance from the axis of rotation of the flap. Sources of information taken into account in the examination 1. Drawings No. 19380000000 and No. 19380700000 of the Rubtsovsk PKTI Traktorostroeni, E ± 3

Claims (1)

Claim Installation for removing non-magnetic metallic inclusions from the molding sand mixture, containing sand separation and sedimentation chambers, estrus and an air collector, characterized in that, in order to increase separation efficiency and improve safe working conditions, the installation is equipped with a rotary shield installed between the separation and deposition chambers of sand with the possibility of rotation towards the deposition chamber, and on the working surface of the shield from the side of the separation chamber horizontal ribs are made, and the height of the ribs is 0.25-0.45 distance Their position from the axis of rotation of the scab.