When we are in a high-pressure environment, gas will be dissolved in the blood due to the high pressure. If we leave the high-pressure environment in a short time, the gas in the blood will dissolve the blood in the form of bubbles due to the pressure release, which is more dangerous at this time. The only way to avoid this is to decompress for a long time so that no gas is produced in the blood, so whether for leisure or professional diving, proper decompression time is absolutely important, Therefore, a waterproof dive watch is also very important. The waterproof dive watch not only can remind the diving time but also with luminous indicator. Then what are the usual characteristics of a waterproof diving watch?
1. The luminous indicator of waterproof dive watches
In the water with darkness and helplessness, we will strongly feel the yearning for the light. As the basis for underwater time reading, all waterproof dive watches will be equipped with eye-catching luminous hands and scales. Usually, the hands, dial scales or watch case/ bezel of waterproof dive watches are coated with fluorescent materials that usually have night light of Swiss C1, C3, and BGW9; the luminous colors are usually white, green, and blue; and the deliberately enlarged hands and dial scales make it easier for divers to read.
2. The rotating bezel of waterproof dive watches
The rotating bezel of waterproof dive watches serves as a reminder of the diving time. The rotating bezel of waterproof dive watches is marked with scales of 15, 30, and 45, for the general diving oxygen cylinder can only provide oxygen for 45 minutes (some are marked with a 60-minute scale). The first 15 minutes are colored or specially marked because divers will strictly observe a 15-minute safety stop when ascending for diving decompression. Usually, you can know the diving time by turning the bezel to ensure that the 0 scales on the bezel is aligned with the minute hands when diving and looking at the scale on the bezel after the minute hands move. The rotation of the external bezel is mostly designed in a single counterclockwise direction, which is to ensure that the time is calculated more, not less, to prevent delays and dangers.
3. The case of waterproof dive watches
The key component of waterproof dive watches is the case whose overall structural design will have an impact on the waterproof performance. However, when it comes to the improvement of the waterproof performance, the main focus is on the glass, the crown, the bottom cover, as well as the case design. We all know that the waterproof dive watches with stronger waterproof ability have thicker cases. Some waterproof dive watches that can be dived into the deep sea have a thick appearance that looks like a home water meter. With a thick case, the mirror surface is the first line of defense for a waterproof dive watch underwater, which is useless if there is no good defense. Therefore, sapphire glass is mostly used in waterproof dive watches now because it has high hardness and almost no fine gaps.
4. The design of the screw crown of waterproof dive watches
Basically, modern watches are equipped with a sealing rubber ring in the groove on the back of the watch so that dust or water can be prevented from entering the inside of the watch case to a certain extent. The fine internal parts of waterproof diving watches are usually wrapped in a closed and thick case, but there is still a place where water can easily enter, that is, the gap in the crown, which is the only part that connects with the outside and the movement. In order to prevent water from entering the movement through the crown, watchmakers have developed a thing called the screw crown, which is designed to optimize the inherent defects of the crown. After the crown is pressed back, the screw crown is rotated and locked forcefully, which will squeeze and seal the waterproof rubber ring to make it have a good waterproof ability. Some watches that emphasize waterproof performance, in addition to the screw crown, will also add shoulder guards or bridges around the crown to provide a more solid protective effect. When the crown is tightened, the water is tightly isolated from the basic waterproof watch. Many waterproof dive watches have upgraded themselves with both a larger crown and deeper pit pattern processing, making them more slip-resistant and convenient for underwater operation. Deep pit patterns that are easier to grasp on the screw crown together with a double-layer safety gasket improve the dustproof and waterproof effect.
5. The twisting back cover design of waterproof dive watches
The twisting back cover of waterproof dive watches is similar to the screw-in crown. The twisting back cover basically shows the corners or grooves that can be rotated, so that it can be screwed into the case, plus a rubber gasket flexibly seals the gap under pressure around. Compared with the push-in back cover, the screw-in design of waterproof dive watches can provide a tighter and lasting waterproof effect. You don't have to worry about hand-washing or rain, and you can easily cope with it when you wear it for swimming. Basic waterproof watch is good enough in general life situations. The back cover design is important, as is the material. The general waterproof dive watches do not use a glass back cover (a few use sapphire glass), and many waterproof dive watches of deep diving series rarely have a transparent back.
6. The helium exhaust valve of waterproof dive watches
" Helium exhaust valve" is a very professional function that is usually used for professional waterproof dive watches. As it is impossible for a full-time diver to go back and forth to the surface every time when working in the deep sea, which will waste too much time to decompress, they must live in a deep-sea high-pressure diving cabin for a long time, but at this time, a considerable amount of gas will be dissolved in the blood, in that case, the air used in the general diving cabin is a "helium" oxygen mixture. Since helium molecules are smaller than water molecules, when we are under high pressure for a long time, helium molecules will penetrate into the waterproof watch to fill it with high-pressure helium gas. Once back to the surface, if the high-pressure helium gas cannot be discharged in a short time, the waterproof dive watch will explode due to high pressure. For the waterproof dive watch with an automatic helium escape valve, its unique automatic helium escape valve processing can ensure that the watch is still safe and reliable even if it is placed in a deep-sea diving cabin for a long time.
7. The anti-corrosion flexible strap of waterproof dive watches
Whether stroking arms or operating instruments underwater, we need our wrists to move flexibly. At this time, the watch needs to be tightly fixed on the wrist. Although many waterproof dive watches are equipped with a metal strap, the chemical composition in the seawater will cause slight corrosion to them, in that case, it is still recommended to replace them with rubber straps, canvas, or synthetic fiber straps with better water resistance and corrosion resistance during diving.