The PVC inflatable boat is a reliable boat, but it has one critical drawback: the dependence of internal pressure on ambient temperature. When you pump the cylinders on the shore in cool weather and go out in the open sun, the air inside expands, creating excessive stress on the seams and material.
It is to prevent tissue rupture and violation of the tightness of the seams that it is required safety-valveThis small device acts as an emergency pressure relief, releasing excess air when the readings are above the permissible limits.
In this article, we will discuss in detail the process of installing an additional valve, which will become your insurance against expensive repairs or complete loss of the boat.
Principle of work and the need for duplication
The standard valves of the bayonet or petal type often stick or fail to relieve pressure when heated in shallow water. pressure It will not reach the critical point of break.
The design of these valves is simple: inside is a spring tuned to a certain force, and once the air pressure exceeds the compressive force of the spring, the membrane rises and pits the excess.
⚠️ Warning: Installing the valve does not negate the need to monitor pressure with a pressure gauge. The device only works in emergency situations of overheating.
Boat owners often ignore this upgrade until they encounter a balloon popping in the sun, and installing an additional unit is a preventive measure comparable in importance to having an anchor or a life jacket.
In addition, the presence of a backup valve simplifies the process of pumping the boat with powerful compressors, avoiding accidental pumping of cylinders above normal. PSI or bars.
Choosing the right valve and tools
The market offers different models, but for PVC, the most relevant threaded valves with a wide base for gluing are the products that have the same thread diameter as the pump or adapter.
Besides the valve itself, it is critically important. glueUse only two-component polyurethane formulations designed for boats, such as: Tearfix or KlejpurConventional household glue will not withstand the stress on the tear and elasticity of the material.
List of necessary tools and materials:
- 🛠️ The safety valve itself (preferably with the possibility of adjusting the pressure).
- 🧴 Degreasing agent (acetone or special solvent for PVC).
- ✂️ Scissors and a stationery knife to cut patches.
- 📏 Marker and ruler for accurate marking of the center.
You'll also need a dryer to activate the glue and a roller. If you don't have a professional roller, you can use a smooth screwdriver handle wrapped in fabric, but the result will be less predictable.
Surface preparation and installation site marking
The choice of place to install is not just a matter of aesthetics, but a technical necessity. The valve should be located at the top of the cylinder, so that when you peel it out air, not water, if the boat is on the wave.
Carefully inspect the surface, without creases, seams or old repairs, the ideal place is a flat area in the middle of the balloon or closer to the nose, where the sun heats up the most intensely.
Surface preparation process:
- Blow the balloon to a state of light elasticity so that the material spreads, but does not stretch.
- Degrease the installation site with alcohol or special solvent. Do not use gasoline, it can damage the structure of PVC.
- Cut out of pieces of PVC (going in the remplekt) a round or oval patch with a diameter of 10-12 cm.
- Mark the center of the patch and drill or gently cut the hole under the valve thread.
Tightness Any speck of dust or fat spot will be the starting point for detachment under pressure.
It is important that the hole in the fabric of the boat (if you decide to hit the valve directly, rather than the patch) was made smoothly, without shaggy edges. However, professionals recommend gluing the reinforced patch first, and mount the valve into it.
Technology of gluing and installation of valve
The most critical step is to apply the glue. Two-part compounds require precise proportions of mixing the hardener and the base, and a misdose will cause the glue to either not dry or become brittle.
Apply the first thin layer of glue on the skimmed surface of the boat and on the back of the patch. Let it dry to a "stick" state (usually 10-15 minutes). Then apply a second, thicker layer.
While the second layer is still sticky, but does not soil the hands, you need to glue:
- 🔥 Actively warm the glued surfaces with a building hair dryer to 60-70 degrees.
- 🤲 Combine the hole in the patch with the marked center on the balloon.
- 👇 Tightly press the patch and carefully roll from the center to the edges, expelling air bubbles.
- 🔩 Insert the valve into the hole and fix it with a nut on the inside (if the design allows) or simply screw it after full polymerization.
Once the valve is installed, the gluing site needs to be warmed up again and pressed very tightly, and the rolling pressure should be uniform throughout the area.
⚠️ Warning: Don't try to inflate the boat immediately after gluing! full glue polymerization takes 12 to 24 hours depending on air temperature.
Violation of drying technology will lead to the fact that under the pressure of the balloon patch simply "shot" together with a part of the fabric.
Checking tightness and setting pressure
After the adhesive is completely dry, you need to do a test. Pump the balloon to the operating pressure specified by the boat manufacturer (usually about 0.2-0.25 bar).
Use a soap solution to check, apply the foam to the valve installation site and the patch perimeter, and the appearance of bubbles will indicate the place of etching.
Table of typical parameters for setting:
| Valve type | Activation pressure (bar) | Case material | Recommended application |
|---|---|---|---|
| Standard petal | 0.3 - 0.4 | Plastic/Resin | Small boats, calm water |
| Spring-operated | 0.25 - 0.6 | Brass/Aluminum | Tuning boats, hot climate |
| Emergency discharge | 0.5 - 0.8 | Stainless steel | Professional vessels, high loads |
If the valve is adjustable, adjust it to a value 10-15% above the working pressure of your boat.
Check the mechanism by pressing the valve rod lightly, the air should come out freely, and after release, the valve should immediately block the flow.
☑️ Final installation check
Operation and maintenance of the security system
An installed valve requires minimal but regular maintenance. Sand, salt and dirt can clog the mechanism, preventing it from closing or, conversely, causing sticking.
After each trip, especially in salt water or sandy conditions, wash the valve with fresh water. periodically lubricate the threads and moving parts with silicone lubricant, which is safe for rubber and PVC.
Visual examination Check if there's a crack in the valve body or if the patch has started to break.
If you notice that the boat was poisoning the air through the valve even at normal pressure, the sealing gum may have worn out. You can replace it by disassembling the device.
⚠️ Warning: Never paint the valve with solvent-based paints that can corrode the plastic or rubber of seals.
Compliance with these simple rules will prolong the life of your boat and ensure safety on the water.
Frequently Asked Questions (FAQ)
Can I install a valve without removing the boat from the transom?
Technically possible, if you have access to the top of the cylinders, but for quality rolling and degreasing, it is better to dismantle the boat or at least turn the cylinder over to work with a flat surface.
Will the valve knock the pressure settings if I pumped a boat in the garage and went out in the sun?
Yeah, that's what it's designed for. If the garage was 20°C and the sun was 40°C, the pressure inside would grow, and the valve would blow the excess, keeping the seams intact.
Which glue is better: single or two-component?
Only two-piece (hardener) single-component adhesives (like "Moment") remain elastic and do not hold high tear pressure, they are only suitable for minor shoe repairs, but not for power elements of the boat.
Do I need to lubricate the valve thread before screwing?
Yes, use silicone lubricant, which will make it easier to screw in and prevent biting of the thread, and also provide additional tightness of the connection.