How to use the compass?

The principle and characteristics of magnetic compass The magnetic compass is a pointing instrument designed according to the principle that the magnetic needle can point to the north (south) pole of the earth's magnetism under the geomagnetic force. As an important navigation instrument, magnetic compass has been installed on ships for a long time. At present, although modern ships have been equipped with advanced navigation instruments such as gyro (gyro compass) and GPS, modern magnetic compass is still installed and used as an essential navigation instrument because of its simple structure, reliable performance and no influence from external conditions. The International Maritime Organization (IMO), classification societies of various countries and ship inspection agencies all clearly stipulate that marine ships should be equipped with magnetic compasses, and their deviations should be corrected correctly, and they should be equipped with deviation tables. 2 magnetic compass classification A According to whether there is liquid in the magnetic compass basin, it can be divided into liquid compass and dry compass. The liquid compass is suspended in a basin filled with liquid. Because of the damping effect of liquid, the stability of compass is better when the ship swings. In addition, due to the buoyancy of the liquid, the friction between the supporting pin and the bearing of the compass can be reduced, thus improving the sensitivity of the compass. Our products are all liquid compasses. B According to the purpose of magnetic compass, there are mainly standard compass and steering compass. The standard compass is usually vertical and installed on the top deck (compass deck) of the cab. Because of its high position, no shelter and little influence by ship magnetism, it is used to observe the course, determine the target position and correct the steering compass, so it is called the standard compass. The steering compass is generally desktop and installed in the cab for observing the course and steering. Our company produces various types of standard compasses and steering compasses. C According to the diameter of the compass, commonly used 190 mm, 165 mm, 130 mm, 100mm 3 magnetic compasses and the magnetization of the geomagnetic field on the steel ship will produce ship magnetism and affect the pointing accuracy of the magnetic compass, which is called "deviation". This deviation can be corrected by a compass. The magnetic compass produced by our company is equipped with an efficient automatic deviation correction device. 4 Installation of magnetic compass A The magnetic compass should be installed on the longitudinal centerline of the ship as far as possible, and the first line of the compass cabinet should coincide with (or be parallel to) the longitudinal centerline of the ship. B the minimum distance between a standard magnetic compass and any ferromagnetic substance is 1 m. 5 Daily maintenance of the magnetic compass A Usually, the magnetic compass should wear a compass cap (the standard compass should wear a compass cover). B keep the liquid in the bowl colorless and transparent, and eliminate bubbles. C, keep the roller shaft and ring shaft lubricated and rotate flexibly. Check the half cycle and sensitivity of the compass regularly, and replenish water to the compass if necessary. E magnetic objects should not be placed near the compass, and the compass should not be placed in high temperature and vibration environment for a long time.