Dead man control in blasting

The dead man control is a remote command system that controls the abrasive flow from the end of the hose, next to the blast nozzle. It consists of a trigger or lever that the operator activates while working: while held pressed, the equipment projects abrasive; when released, the projection stops immediately. Its name —"dead man"— describes exactly its principle: the system only works while the operator actively holds it.

The foundation of the dead man control is operator safety. In equipment without this system, if the operator drops the hose due to an accident, a stumble or a loss of control, the hose keeps projecting abrasive freely, whipping uncontrollably. At the working speeds of blasting —over 300 km/h— an abrasive burst can cause serious injuries. The dead man control eliminates that risk at the root: the instant the operator stops holding the trigger, the projection stops. That is why it is an essential accessory for any safe and reliable manual blasting process.

Although safety is its main function, the remote control provides concrete operational advantages. It reduces support labor: the operator controls the start and stop without needing a third party to operate the pressurization and depressurization of the tank. In rooms with automatic abrasive recovery, by commanding the depressurization of the pot it allows automatic abrasive reloading. And it minimizes consumption: the operator cuts the projection during the moments of repositioning the part or moving, avoiding wasting abrasive when not blasting.

The dual control adds a second function to the remote control: it allows selecting, from the same end of the hose, between projecting abrasive or projecting only compressed air for blow-off. With a single hose and without changing equipment, the operator alternates between blasting and blowing off the abrasive accumulated on the part or work area. This significantly speeds up the process: cleaning loose abrasive, which normally requires stopping work and switching tools, is done on the spot from the same station.

A standard blasting unit is converted into a remote control system through an easy-to-mount transformation kit, without replacing the pot. There are two types of control depending on the need. The low-voltage electric control offers a practically instantaneous cut-off speed, which makes it suitable for working with long hoses, over 20 meters; it usually incorporates a ball-and-chain actuation that reduces operator fatigue. The pneumatic control is a simpler and lower-cost solution, with a manual selection valve, but due to its longer reaction time it is not recommended for hoses over 20 meters, and it requires the operator to carry somewhat more weight. The choice between one and the other depends on the hose length and the working conditions.

The system selection depends on three factors: the distance between the operator and the pot (which defines the hose length and, with it, whether electric or pneumatic control is preferable), the need to alternate between blasting and blow-off (which points toward the dual system), and the operation frequency (which may justify systems that minimize wear on the cut-off hose). CYM Materiales manufactures its blasting pots in four control variants —manual, remote, dual and pinch— and provides the kits to transform existing equipment. The complete comparative table of the four systems is available on the blasting pots page.

The dead man control is, first and foremost, a safety system that protects the operator from the high-speed projections of blasting. But it also reduces labor, saves abrasive and —in its dual version— speeds up the process by combining blasting and blow-off. And it requires no new equipment: a conversion kit transforms the pot you already own into a remote control system.