Never underestimate the power of a hose under pressure
Pressure is still often underestimated. We mean pressure in terms of operating pressure on a hose. Once, a customer sent us the YouTube video below with the question: “This happens to us so often. Do you have a hose that doesn’t do this?” Our answer was “no,” such a hose does not exist. But we can protect the hose with a simple solution.
The hose is hanging loosely
The video above shows a construction site where concrete is being poured. The concrete hose hangs loosely over the site. When the concrete pump is switched on, a pressure wave moves through the hose. We’ll skip the physics explanation, but according to Newton’s Law, every action has an equal and opposite reaction. At the hose’s end, this results in an uncontrolled swinging motion.
Delivering a powerful blow
Such a hose can deliver a powerful blow, causing serious injury. In this video, you should consider yourself lucky that no one is nearby. The customer who sent the first video asked if there is a hose available that doesn’t whip around like this. But that’s impossible, because a hose is inherently flexible. The solution is to secure the hose at the end, ensuring it is fixed and cannot swing freely.
Literally whipped away
Holding a hose alone or with a few people is life-threatening. What happens then can be seen in the video below. Even the muscular construction worker is literally whipped away when the pump is switched on. In hindsight, it’s laughable, but if the hose had hit his head, the worker wouldn’t have been able to tell the story.
Definitely don’t try to rig it yourself
There are various ways to secure a hose against whipping. Often, the hose is fastened with a steel cable to a fixed point, called a "whip check." There are many other proven methods tailored to the application, type of hose, working pressure, medium, and any relevant environmental factors. These methods can be applied to almost all types of hoses, not just the concrete pump hoses shown here. Definitely don’t try to rig it yourself—consult an expert for advice.
Never leave it lying loose anywhere
One important tip is to never leave the end of a hose lying or hanging loose anywhere while it is connected to a pump. Even if the pump is switched off. Definitely do not leave the hose loose when it is pressurized. This can be life-threatening.
Finally, here is a short video from WorkSafeBC demonstrating a similar situation. It gives a clear picture of exactly what happens to the hose when pressure is applied.