Life Raft Category
Life rafts can be divided into rigid life rafts and inflatable life rafts according to their structure. The former's main structure is made of a rigid material; the latter is made of rubber and nylon cloth as the main material.
(1) rigid life raft
The rigid life raft, also known as the traditional life raft, is constructed by using a galvanized iron sheet, an aluminum alloy sheet, a stainless steel sheet or a hard plastic material around the life raft to form a plurality of joint air boxes as the main buoyancy part of the life raft. The outer layer is then covered or not covered with flame retardant material; the top of the crucible is provided with a fixed rigid canopy and the entrance and exit, and the bottom of the crucible is a wooden grate plate. It is usually stored on the ship's side sloping ramp or on the deck of the bridge. When it is applied, the carriage fixing hook is opened, and the carriage slides off the water by itself or the sling is used to release the water.
The biggest feature of this type of life raft is its simple structure and low cost; but it is bulky, heavy and has few staff members.
(2) Inflatable life raft
Inflatable life rafts are further divided into inflatable life rafts, inflatable lifesaving buoys, and inflatable self-supporting life rafts.
1. inflatable life raft
These life rafts provide buoyancy from upper and lower floating tires made of rubber material, and are made of double-layer waterproof nylon cloth, which is inflated with gas into a small plaque with a tent, such as a circle, an oval or a polygon. After the liferaft body is folded up, it is stored in the FRP storage cylinder together with the attachment. The inflatable life raft is widely used in various civil and military vessels at sea because of its advanced design, compact structure, good safety, convenient movement, simple operation and rapid forming.
There are two types of inflatable liferafts, mechanically suspended and thrown. The mechanical hanging type raft has been inflated before entering the water; the throwing type life raft is inflated on the sea surface, and the life raft may be overturned during the inflation forming process, so that the artificial water supply is required to be used for the personnel to board. .
2. Inflatable rescue float
In addition to the awning, the inflatable life-saving buoys have the same manufacturing materials, main structure, performance requirements, forming process, storage requirements, and attachments, all of which are the same as the inflatable life rafts, but the casting method is only throwing type. . Its characteristics are:
(1) There is no canopy.筏 After the water surface is inflated, the water can be easily and quickly embarked by two people on the two boarding platforms or any one side of the floating device.
(2) The rated occupant has more inflatable life rafts than the tent, and can carry up to 50 people.
(3) The double bottom of the rescue buoy is placed between the upper and lower floating tires. Therefore, no matter what sea conditions are applied, the floating device is in a positive floating state after being inflated and formed on the sea surface (both sides are available), and no artificial righting is required.
(4) Because there is no canopy for such life-saving buoys, the personnel are greatly affected by sea conditions and climate, and are mainly equipped on passenger ships.
3. Inflatable self-supporting life raft
In order to overcome the overturning situation that the inflatable life raft can form during the sea surface forming process, to avoid the difficulty of people getting in and out of the water, to meet the needs of the sea health workers for safety and rapid response, some manufacturers have developed inflatable self-supporting life rafts. Such a life raft is once overturned on the sea surface during the application process. Since the top of the raft is rounded, the contact surface with the water can be reduced. The weight of the corpus callosum and the attachments is at the bottom of the life raft. After inflation molding, you can self-righteously. 
The main requirements of the LSA Rules for life rafts are:
(1) The liferaft shall be structurally capable of withstanding exposure to float for 30 days in all sea conditions.
(2) The life raft and its attachments can be used safely and normally after being put into the water from a height of 18 m.
(3) The liferaft body floats on the water and can withstand repeated pedaling from the bottom of the rafter at least 4.5 m without damage, and does not affect normal use.
(4) The liferaft carries all the occupants and attachments and releases a sea anchor, which can be towed at a speed of 3 kn in still water without damage.
(5) The life raft shall have a canopy that can be automatically propped up when landing on the surface to protect the occupants from exposure.
(6) The life raft shall have a fixed occupant of not less than 6 persons.
(7) The total mass of life-saving carcasses, belongings and containers shall not exceed 1 85 kg. In addition, specific requirements are placed for the installation of the liferaft, the liferaft's deflating facility, the strength of the suspended liferaft, the boarding, the container for the container, and the free floating and lowering. 
(1) Liferafts and their storage devices shall not affect the use of life-saving appliances stored in any other location.
(2) As far as practicable, as close as possible to the surface of the water. Life rafts other than liferafts that need to be thrown out of the way should be in such a position that the life raft at the embarkation position, when fully loaded at 10° at an unfavorable trim, and plunged to any side of the ship up to 20 ° When crossing the angle of the water to the edge of the open deck of the ship (whichever is greater), it should be no less than 2 m from the waterline.
(3) When the hoistable life raft is in the ready-to-use state, the two crew members should be able to complete the boarding and landing preparation work within 5 minutes.
(4) Store in a safe and sheltered place and protect it from fire and explosion. Especially the survival craft on the tanker. It should not be stored above cargo tanks, slop tanks or other cargo compartments containing explosive or dangerous cargo. 
Check maintenance editor
(1) Visually inspect the life raft and its storage and discharge equipment weekly to ensure that it is immediately available and records are made.
(2) Every month, the quick decoupling, fixing rigging, first cable, rope plug, connecting shackle, seal on the liferaft container on the liferaft storage rack shall be inspected once and found to be damaged or not ready for use. It should be repaired immediately, in a good state of technology, and to be well documented.
(3) The time interval for maintenance of life rafts shall not exceed 12 months and may be extended to 17 months with the consent of the competent authority.
(4) The life raft must be inspected at the inspection station approved by the competent authority, or the certified personnel recognized by the competent authority shall inspect the life raft system on board as required. The main items of maintenance include: inspection of the surface quality of the carcass (sticky, damaged, etc.), inspection of the container of the carcass, inspection of the armor of the carcass, inspection of the life preserver, inspection of the product, and inspection of the gas cylinder Check, start the striker, start the drawstring check, perform the inflation test and check. In short, these inspections should not neglect any small parts, any one part, any one of the armor, or any one of them. All bad conditions such as shortage, damage, mildew, etc., must be added, repaired or replaced to keep them in good technical condition.
(5) Under normal storage and use, the life span of the liferaft is 10-15 years, which must be replaced after the service life.
(6) If the hydrostatic pressure release device can be exchanged on board, the ship must have qualified spare parts. After the use expires, it must be replaced in time.
(7) Hydrostatic pressure release device (except for self-replacement), the inspection interval is 12 months; with the approval of the competent authority, it can be extended to 17 months.
(8) The surface of the container of the life raft should never be painted. The signs and technical data marked on the container must be clear and obvious. It is not possible to add a cover on the container. It is not possible to add a fixed rigging.