| 摘要 |
System for blasting objects by means of a blasting head (1) with a blasting medium (2), the medium contains a blasting fluid comprising a mixture of a transport fluid and an abrasive material. The blasting fluid is supplied to the blasting head through a first conduit (3) connected to the blasting head and air through a second conduit (4). The blasting head is connected through the first conduit and the second conduit to a supply unit (6), controlled by a control element (5) for fluid and air respectively. The blasting fluid and air are combined in the blasting head into the blasting medium, which, under the influence of the supply pressure of the blasting fluid and/or the air, forcibly is sprayed from the blasting head against the object to be blasted. Further is provided a switch (7), for example a dead man's handle on the blasting head, the switch being connected to the control element. In a first state of the switch the supply pressure of the blasting fluid and/or the air has a value by which the blasting medium is forcibly sprayed from the blasting head against the object to be blasted. In the second state of the switch the supply pressure of the blasting fluid and/or the air is changed such that the force of the blasting medium spraying from the blasting head is decreased, however, by applying such control by the control element that in particular is prevented that the first conduit and/or the blasting head are blocked or obstructed by settlement of the abrasive material within the blasting fluid. |
