Open water season is already approaching, and many owners of swimming facilities rush to check their vessels before the first launch. Inflatable boat Polyvinyl chloride is a durable material, but only when properly operated. The most common mistake of beginners, which can lead to rupture of the seams or deformation of the bottom, lies in the procedure of pumping cylinders and inflatable floor.
Many people think that the more inflated the cylinders, the better the boat will hold the wave and go faster, a dangerous misconception that ignores the physical properties of gases as temperatures change. PVC materialThe PVC that you're building is not rubber, it doesn't stretch very much, and the pressure inside the closed volume will cause the junctions to break, so the question of how to pump the PVC boat in compliance with all the regulations is critical to safety on the water.
In this article, we will examine not only the sequence of actions, but also the technical nuances that are often overlooked even by experienced anglers. You will learn why you can not pump a boat in a warm garage, if you lower it into the water in the freezing wind, and what kind of boat you can do. range The pressure is optimal for different elements of the structure.
Physics of the process: why the pressure changes in the sun
Before you start pumping, you need to understand the basic laws of physics that directly affect the condition of your vessel. The air inside the cylinders obeys Gay-Lussac's law: at a constant volume, the pressure of the gas is directly proportional to its temperature, which means that if you pump the boat to the end in the shade at +20°C, and then take it out into the open sun, where the surface temperature of the PVC rises to +40-50°C, the pressure inside will rise dramatically.
That's why. pressure-control It's not a one-off action, it's a constant process in the process of getting ready to go, and many owners who ignore this fact are faced with an unpleasant surprise: a boat that is pumped into the eye at home becomes hard as a rock on the shore, and its sides begin to swell dangerously, at worst, it leads to the divergence of seams, which are the most vulnerable site of the structure.
But a boat that's underperformed is also a problem, and soft boats are worse at quenching the waves, and the boat is rolling and less manageable. Strength of construction If you push the side of the boat more than 2-3 centimeters, then the boat needs to be pumped, and the balance between "not burst" and "not soft" is the main task of the owner.
⚠️ Attention: Never leave a fully pumped boat in direct sunlight unattended. If you can't keep it in the shade, be sure to blow some of the air out of the cylinders to compensate for the thermal expansion.
What is the "drummy eardrum effect"?
This is a condition where the sides of the boat are so tight that they start to ring when impacted, and it's a signal of critical pressure exceeding the risk of rupturing the seams at the gluing sites or at the valves.
Selection of equipment: manual or electric pump
The modern market offers many solutions for pumping watercraft, and choosing the right tool can save you a lot of time and effort. The main division is mechanical (manual) and electric pumps, each of which has its own advantages and use cases, which are worth considering when completing your equipment.
Hand pumps, most often in harmonica or foot models, are classics of the genre, and their main advantage is autonomy and reliability. You don't have to look for an outlet or worry about a discharged battery. large-scale (more than 320 cm long) or high bottom (HDND), the pumping process can take considerable time and require physical effort, which is not always pleasant before fishing or cruising.
Electric pumps speed up the process significantly, especially when filling the main volume of air. Modern models often have a built-in pressure gauge and auto-stop function, which eliminates the risk of pumping. But it is worth remembering that most electric pumps are designed for a large volume of air at low pressure (up to 0.5-0.8 atmosphere). It often takes a very long time to achieve pressure to 1.0-1.2 atmospheric workers with electricians, and here again comes to the rescue. hand-pumping.
- 🔋 Electrical pumps: Ideal for quick initial pumping of large volumes, but require a 12V power supply or a charged battery.
- 💪 Foot pumps: Compact and reliable, allow you to use body weight to create pressure, convenient for medium-sized boats.
- 🤲 Hand-held piston: The classic version of the "accordance", often comes with a complete set, is good for the final adjustment of pressure, but time consuming.
The best strategy is to use a combination approach, first you use an electric or powerful foot pump to quickly shape and volume the cylinders, then you switch to manual mode or use the second stage of the pump to achieve the final operating pressure, which saves battery life and your time.
Use adapters and longer hoses when working with an electric pump, which will reduce the load on the engine of the device, as it will be easier to pump air, and reduce the heating of the pump itself.
Preparation for the process: where and how to lay the boat
The place where you will pump is no less important than the pump itself. The boat should be laid on a level, clean surface. Grass, sand or smooth asphalt will do, but avoid places with sharp stones, spines or hot bitumen that can damage. bottom when heated.
If you're on the shore of a body of water, try to position the vessel parallel to the water's edge, nose against the wind, which will make it easier to descent and prevent the boat from blowing away during the pumping process, which is especially true for lightweight models without bottom. pollutation (if any) or the inflatable valves themselves are in an accessible and clean place so that dust or sand does not get there.
Before you start, check the valves, make sure the valve petals are clean, they don't have sand or villi, mud in the valve is the most common cause of etching air, which is difficult to diagnose on water, wipe the valves with a wet wipe and make sure they are tightly closed before you start working.
It's also important to consider the ambient temperature regime. If you take a boat out of a cold trunk or garage, let it lie down straight for 15 to 20 minutes. The material must take the ambient temperature, straighten the folds, and then you can start pumping. Cold PVC is tougher and less elastic, which can lead to microcracks when you straighten.
Step-by-step instruction: the order of pumping elements
Keeping the right sequence of actions is a guarantee that the boat will take the correct geometric shape without distortion. Chaotic pumping of different compartments can lead to the fact that the structure "spins" and insert a rigid floorboard (floor) will be almost impossible.
The side cylinders are always pumped first, and you don't have to push them to the working pressure right away, you just need to pump them up to about 60-70% of the normal level, so they just spread out and take a round shape, and that creates the necessary framework, but it leaves the material elastic for further manipulation.
☑️ The algorithm of proper pumping
Once the sides are straightened, transom cans (seats) are installed and, if the design provides, a transom plate is then laid, the pitting bottom is laid, it is important to straighten all the folds of the floor so that it lies flat, only after that the sides are finally pumped to working pressure and, lastly, the inflatable floor (Kilson or NDND).
The final step is to check all the valves and joints, and walk your hand through the seams, see if there's any characteristic hissing, and pay special attention to the area around the valves, because that's where the high pressure micro-leaks are most common.
⚠️ Attention: It is strictly forbidden to first pump the inflatable floor, and then the sides. The bottom, inflated, can deform already inflated sides or, conversely, do not fit into the allotted space, which will lead to rupture of the partitions.
Pressure table: how many atmospheres need to be pumped
The most important question is how much to pump, measured in atmospheres (atms), bars (bars) or kilopascals (kPascals). For most PVC boats, the standard is pressures ranging from 0.8 to 1.2 atmospheres. However, different design elements require different approaches.
Below is a reference table of recommended pressures for different parts of the boat, remember that the exact values are always listed in the product passport of the specific manufacturer, and should be given priority.
| Element of construction | Recommended pressure (atm/bar) | Features |
|---|---|---|
| Side cylinders | 0.9 - 1.2 atm | The main part requires rigidity |
| inflatable floor (NDB) | 0.8 - 1.0 atm | Do not pump to avoid damaging the stringers |
| Kilson (inflatable keel) | 1.0 - 1.2 atm | Responsible for exchange rate sustainability |
| Inflatable cans | 0.6 - 0.8 atm | Less pressure for seating comfort |
To measure pressure, it is best to use a pressure gauge built into the pump or separate. It is difficult to determine the exact pressure on the eye, but experienced users use the method of pressing: at normal working pressure (about 1 atm), when pressed on board, it should bend no more than 2-3 mm, remaining elastic.
The golden rule is: Pump the boat to a state of hardness, but not to a state of stone drum. The material must be elastic, but not stretched to the limit.
Nuances of operation: cold, heat and storage
Operating a PVC boat in different weather conditions requires adjustments. Winter fishing or just going out in cold weather dictates its rules. In the cold, the air compresses, and the pressure in the cylinders drops. So, if you pump the boat in the warm, in the cold wind, you will see that the sides have become soft. They need to be pumped out already on the spot, but you need to do this carefully so that you do not pump the boat when it warms up in the sun or from the heat of the body.
In hot weather, the situation is reversed. If you pumped the boat in the morning at +15 ° C, and in the afternoon the temperature rose to +30 ° C and the sun is shining, the pressure inside can increase by 10-15%. On these days it is better to under-pump the boat at 0.1-0.2 atmosphere from normal, leaving room for air expansion. Constantly monitor the rigidity of the sides with your hand.
As for storage, thin storage of the boat in a pumped state is not recommended, as this puts a constant strain on the seams and can lead to "fatigue" of the material. However, short-term storage (during the season) in a pumped form in a shady, cool place is permissible and even useful for straightening the folds, if you have such space.
- ❄️ In winter: Pressure drops, regular pumping is required at the site of operation.
- ☀️ Summer: Pressure is increasing, you need to put excess air in the peak of heat.
- 🌧️ In the rain: The water cools the boat, the pressure may temporarily decrease, but after going out in the sun will rise again.
Proper care and understanding of the processes taking place inside your boat will extend its lifespan for many years. Polyvinyl chloride - a material with a large margin of safety, but it does not tolerate neglect of physical laws and careless handling.
Can I pump a boat with a compressor from a car?
You can use a car compressor, but with great care. Car compressors often develop high pressure and have high performance, which creates the risk of instantaneous pumping and rupture of the seams. Also, they are very warm. If you use an auto compressor, do this in short pulses, constantly monitoring the pressure with a pressure gauge, and do not leave the process unattended for a second.
Why does the boat poison the air after pumping?
Main causes: (1) Dirt or sand in the valve (need to be cleaned or blown). (2) Wear of rubber valve pad (replacement required). (3) Microcracks in the material or seam. Use a soap solution to look for leaks - apply it to suspicious places, and bubbles will indicate the source of the problem.
Do I have to completely lower the boat after every fishing trip?
You don't have to descent the boat completely after each exit if you keep it in the right conditions (in the shade, at moderate temperatures), just put a little pressure (by 20-30%) to compensate for the temperature changes during storage, full deflation is only required for transportation or long-term storage.