DD286775A5 - ANNEX TO THE PRESSURE AIR RADIATION - Google Patents

Abstract

The invention relates to a system for compressed air blasting with gekoernten solids, especially for the surface treatment of profiles and sheets in the metalworking industry to achieve metallically bright surfaces, for cleaning Gieszereierzeugnissen and for cleaning house facades and stone sculptures. The system should be simple and compact and easy to handle, characterized by a high blasting performance and exclude precipitation. According to the invention, two leads leave one T-piece. The first line is led into the upper area of the pressure vessel, the second line is designed as a mixing tube and leads horizontally through the lower area of the pressure vessel. The mixing tube has in the area located in the pressure vessel on a downwardly facing OEffnung, which is adjustable in their size. Fig. 1 {Appendix; Jets of compressed air; Management; Mixing tube; Pressure vessel; Throttle valve; Pressure difference}

Description

For this 1 page drawing

Field of application of the invention

The invention relates to a system for compressed air blasting with granular solids, in particular for the surface treatment of profiles and sheets in the metalworking industry to achieve metallically bare surfaces, for cleaning foundry products and for cleaning house facades and stone sculptures.

Characteristic of the known technical solutions

Systems for compressed air blasting are already known in a wide variety of variants. Differences arise mainly in the type of metering of the radiation agent in the air flow. With the DDFI device PGEF 80, the radiation, supported by the air cushion in the boiler, falls on a rotatably mounted pan, which is located in a closed mixing chamber. The air flow is passed through the mixing chamber. If the pan is in a vertical position to the radiation medium outlet, it runs full and the stream of abrasive material is interrupted. According to the flip-flop of the pan, the flow of radiation is regulated. In DE-OS 2843209 a solution is described in which the blasting agent falls through a Einstellschiober in the air flow.

In DE-OS 3011344 a pressureless boiler is described. The air is guided along below the Kescels. The blasting agent falls by gravity into the mixing chamber. However, there is no direct connection from the mixing chamber to the blasting agent container, since the blasting agent falls through a system of rotatable perforated discs, which are arranged so that the compressed air can not get into the blasting agent container.

In the solution described in DE-OS 3407710, the blasting agent is passed through an S-shaped piece of pipe in the air jet. This tube runs in places straight, so that the blasting agent can not get into the air line alone by its gravity. Only a pressure difference between the air line and jet boiler allows flow of the blasting agent in the air jet. According to DE-OS 3025895 the blasting agent also falls through an adjusting slide in the air stream. In the outflow line of the container behind the connecting line of the compressed air guided past the container in a bypass line, a pneumatically, hydraulically or electromechanically actuated shut-off valve is installed. This reduces delay times at the beginning and end of the operation.

In addition, the companies Atlas-Copco (Sweden), Clemco (USA) and Orcza (UVR) are offered compressed air blasting systems based on the above principle, but the blasting agent is metered by manually operated shut-off devices.

Disadvantage · -] in the solutions described, except in DE-OS 3407710, is that the respective metering devices are subject to heavy wear by the blasting agent acting on them. All solutions described have the further disadvantage that, especially when using sharp-edged blasting agents during operation or as a result of technologically induced work breaks, blockages in the mixing devices occur. In a further described solution, the blasting agent is already mixed in the Strahlkossel with a portion of the jet air and conveyed against gravity from the blasting pot. The total air flow from the compressed air generator is divided so that the ers'.e share compressed air übet a pressure tube enters the boiler and this can only rely on a centrally located in the pressure tube suction pipe again. In this case, the blasting agent is entrained in the area of the air deflection and combined outside the boiler with the second part of the compressed air, which is conducted past the boiler via an adjustable bypass. With regard to the use of sharp-edged, clogging-prone blasting agents, this operating principle has a high reliability. However, a disadvantage is the relatively high production costs.

Ziol of the invention

The aim of the invention is to provide a system for compressed air blasting, which is simple and compact and easy to handle, is characterized by a high beam power and excludes failures.

Essence of the invention

The object of the invention is to develop a plant ium compressed air jets, which ensures a high Sfahlleistung by an effective mixing process with low pressure losses and in which the blasting agent-air mixture is precisely dosiorbar and easily reproduced.

According to the invention, this object is achieved by dsS. outgoing from a T-piece, a pipe into the upper area of the pressure vessel leads and a mixing pipe is led horizontally through the lower area of the pressure vessel. The mixing tube has in the area located in the pressure vessel on a downwardly facing opening, which is conceivable in size. Due to the resulting different pressure conditions, the blasting medium is sucked against gravity and conveyed into the blasting hose. Through a throttle valve, the beam intensity is precisely adjustable. Clogging and thus failure of the system can not occur.

Auiführungtbeltplel

The invention will be explained below with reference to an embodiment. The accompanying drawing shows

Fig. 1: an overall view of the system for compressed air blasting.

The plant for compressed air blasting consists of a pressure vessel 1, to which two wheels 2 are mounted for movability.

Dioser closes automatically when the pressure vessel 1 is pressurized via the line 4 with compressed air.

The air supply takes place from the compressed air generator via a connecting piece 5 in the T-piece 6. By means of a throttle valve 7, the compressed air is metered for the mixing process. When the throttle valve 7 is closed, the compressed air via the line 4 into the pressure vessel 1. Here, an overpressure builds up. By opening the throttle valve 7, the conveying air flow passes into the mixing tube 8, which extends horizontally through the lower part of the pressure vessel 1. Due to the suction effect of this conveying air flow and the pressure gradient between the inner space of the pressure vessel 1 and the air pressure in the mixing tube 8, the blasting medium 9 is conveyed through an opening 10 provided on the underside of the mixing tube 8 into the mixing tube 8 and transported to the blasting nozzle.

To connect the blasting hose to the mixing tube 8 is a connection piece 11th

Claims (2)

1. plant for compressed air blasting with granular solids, consisting of a compressed air generator, a pressure vessel with blasting agent and a hose with jet nozzle, characterized in that, starting from a tee (6), a line (4) in the upper part of Pressure vessel (1) leads and a mixing tube (8) is guided horizontally through the lower portion of the pressure vessel (1). 2. Plant for compressed air blasting according to claim 1, characterized in that the mixing tube (8) has a downwardly facing opening (10) whose size is adjustable.