SE465116B - BLASTING DEVICE FOR STEEL PRODUCTS - Google Patents

Description

465116 2 the walls of the blasting chamber, and the rear end of the tube is also connected from the outside to the blasting chamber space.

The steel sand that may flow out of the blasting chamber ends up in the end chambers, from where it falls into the suction pipe at the bottom of the suction chamber, and is carried further by the suction current into the cyclone for sand circulation and removal of dust. In this way, the steel sand can be utilized in the best possible way, while the area around the device is kept sand-free.

According to a preferred embodiment of the invention, an additional injection pipe is connected to the rear end of the suction pipe arranged on the bottom of the blasting chamber to direct compressed air into the suction pipe. In this way, the sand circulation will be more efficient at the rear end of the blasting chamber, where otherwise it is difficult to set the sand in motion.

Furthermore, it is important to be able to regulate the sand flow from the pressure vessel so that a controlled sand circulation can be ensured. For this purpose, the sand flow pipes are preferably made of an elastic material and provided with mechanical throttling means.

In the following, the invention is described in more detail with reference to a preferred embodiment according to the accompanying drawing.

Figures 1 and 2 show the blasting device in its entirety, seen in two different directions.

Figure 3 is an end view of the blasting chamber.

Figures 4 and 5 show how the sand and air currents combine before blasting.

Figure 6 is a side view of the blasting chamber.

Figures 7, 8 and 9 show more detailed views of the lower part of the blasting chamber, i.e. sugsilon.

Figures 1, 2 and 3 show the blasting device according to the invention intended for steel products, such as profile steel, which device has three main parts, a pressure vessel 1, a blasting chamber 2 and a cyclone 3 for sand circulation and dust removal. The blasting chamber 2 preferably has four blasting nozzles 7, all of which are connected by means of rubber tubes 5 to a point below the pressure vessel 1, where the compressed air stream from a hose 4 and the sand stream under pressure from a rubber tube 10 are joined. The parts of the blasting chamber 2 which are exposed to the blasting are provided with a rubber coating. On the inlet and outlet side of the barracks (figure 3) are further arranged rubber pullers 6, which are driven by means of a V-belt 14 by a cylindrical gear motor 15. A drive motor for the cyclone 3 is denoted by the reference numeral 9. At the ends of the blasting chamber, on its inlet and outlet side, separate end chambers 24 and 25 are formed for collecting the sand which may flow out of the inner space of the blasting chamber.

The end walls of the end chambers are formed by two sealing plates 26 of rubber arranged on each other and split in the middle towards the sides. For setting the position of the blasting chamber in the vertical direction, for example, a combination of a lever 12 and a spindle 13 can be used, as shown in Figure 3. The blasting chamber and the end chambers are described in more detail in connection with Figure 6.

The sand-air mixture under pressure is introduced into the blasting nozzles 7 arranged in combs 3 (not shown in figure 3) to perform a spray cleaning on the surface of profile steel. The profile steel moves continuously through the blasting chamber 2, and if necessary, the speed of this movement can be varied. Cyclone 3 for sand circulation and dust removal is constantly underway; blasting process fi and removes dust from the blasting chamber and lifts the steel sand entering the blasting chamber into a falling chamber of the cyclone 3, which is arranged above the pressure vessel, for reuse of the steel sand.

For this purpose, the cyclone 3 is connected by means of a pipe 8 to a suction pipe 20 at the lower part of the blasting chamber 2. When the profile steel to be blasted or the steel sand runs out, the steel sand present in the drop chamber can be quickly emptied into the pressure vessel 1 arranged below it for reuse.

The sand flow is regulated and the sand and air flows are combined by means shown in Figures 4 and 5. By throttling the rubber pipe 10 with a regulating choke 11, the pressurized sand flow from this pipe, which is connected to the lower part of the pressure vessel 1, is regulated. The rubber tubes 10, each with its own control choke arranged under the pressure vessel 1, are four in number, i.e. one for each blasting nozzle 7. By means of the control chokes 11 it is possible to discharge a suitable amount of steel sand from the lower part of the pressure vessel to mix with the compressed air which comes through the hose 4 from the upper part of the pressure vessel.

Figure 6 shows the blasting chamber 2 from the side. The end chambers 24 and 25 at each end of the blasting chamber are separated from the interior of the blasting chamber by means of a rubber sealing plate 27, which is similar to the rubber sealing plates 26 forming the end walls of the end chambers. Further, inside the blasting chamber, at least in front of the end chamber 24, which is located opposite the blasting nozzles 7, a rubber curtain 28 is arranged, which consists of suspended rubber strips. The lower parts 24a and 25a of the end chambers are tapered downwards and by means of vertical connecting pipes 29 and 30 are connected to the ends of the suction pipe 20, which suction pipe is arranged along the bottom of the suction silo 19, which silo forms the lower part of the blasting chamber. The jacket of the suction pipe 20 has suction gaps 21 for distributing the sand flow. The blasted sand used flows downwards along the edges of the suction silo 19 and enters the suction pipe 20 through the suction slots 21 along the entire length of the blasting chamber. The suction current into the suction tube 20 is provided by the suction action of the cyclone 3 through the tube 8.

Since it is more difficult to set the sand in motion in the rear end of the suction pipe 20, an additional injection pipe 31 has been arranged there, through which compressed air is injected into the suction pipe substantially in the longitudinal direction of the pipe. In this way, the sand can be set in motion in the best possible way along the entire length of the suction pipe.

To streamline the sand flow, the suction pipe 20 can have an additional suction pipe 22, which provides an extra air flow at the rear end of the suction pipe 20 (Figures 7-9). In order to keep the total negative pressure inside the chamber unchanged (important with regard to dust removal), the air entering the extra suction pipe is taken from the chamber 2. The running sand somehow falls into the passing air stream and follows it so that it is removed from the chamber. The suction current in the chamber is provided by means of the cyclone assembly 3 connected to the pipe 8.

The lower of the blasting chamber can be adjusted vertically e.g. by means of a combination of a lever and a spindle 12, 13, as shown in figure 3. The chokes 11 for regulating the sand flow can work with the same principle.

Although the invention has been described herein by reference to the examples in the accompanying figures, it is apparent that the invention is not limited thereto, but those skilled in the art may vary it in several different ways without departing from the spirit of the invention.

Claims (3)

465116 PATENT CLAIMS Blasting device for steel products, which device has a pressure vessel (1), a blasting chamber (2), a cyclone (3) for sand circulation and removal of dust and means for guiding the sand-air mixture under pressure from the pressure vessel to the blasting chamber and sand from the blasting chamber to * x the cyclone (3), wherein a suction pipe (20), the jacket of which is provided with suction openings (21) for distributing the sand flow, is arranged on the bottom of the blasting chamber (2) to make the sand circulation more efficient, characterized in that the suction pipe (20) is connected at its two ends to end chambers (24, 25) formed in the ends of the blasting chamber (2), the product to be blasted being arranged to enter and exit the blasting chamber (2) through said end chambers. . Device according to claim 1, characterized in that the lower parts (24a, 25a) of the end chambers (24, 25) are tapered downwards. Device according to claim 1, characterized in that an additional injection pipe (31) is connected to the rear end of the suction pipe (20) for conducting compressed air into the suction pipe (20). J.