Sand blasting method

Abstract

According to the sand blasting method, a sand blasting trolley body is a sand blasting pipe, the front end of the sand blasting pipe is connected with a sand blasting nozzle through a sand blasting nozzle fixator, a supporting pipe is arranged below the sand blasting pipe, and multiple sets of walking wheels are arranged at the bottom of the supporting pipe. The rear end of the sand blasting pipe is connected with a sand blasting machine, a pulling rope is installed at the front end of the sand blasting machine, the sand blasting pipe is placed into the pressure stabilizing cavity from one end of the sealing box, the front end forwards controls the speed through the pulling rope, the rear end polishes the interior of the pressure stabilizing cavity through sand sprayed by the sand blasting machine, and the polished sand is directly sprayed out through an underground air spraying hole in the pressure stabilizing cavity. And the sand blasting trolley enters from the sealing box at one end of the pressure stabilizing cavity and exits from the other side. By means of the sand blasting trolley, the problem of sand blasting in the narrow space is solved, the sand blasting trolley is key equipment in an air reservoir reduction system, it is guaranteed that the sand blasting trolley conducts sand blasting in the narrow space, the interior of the pressure stabilizing cavity is polished, the sand blasting period is shortened through the walking wheels, and unmanned sand blasting in the narrow space can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of ship gas drag reduction, and in particular relates to a sandblasting method. Background Art

[0002] Ship gas drag reduction technology is a technology that forms a stable gas lubrication layer by introducing air into the bottom of the ship during the ship's travel, thereby reducing the friction resistance of the ship's surface. The ship's air layer drag reduction system includes an air supply system, a pressure stabilization chamber, and a jet hole. The jet hole is arranged on the bottom plate of the ship and is connected to the pressure stabilization chamber. When the ship is traveling, the air supply system supplies air to the pressure stabilization chamber, and the gas in the pressure stabilization chamber is ejected to the outside of the hull through the jet hole to form a gas lubrication layer on the bottom of the hull that can reduce resistance.

[0003] In order to ensure stable pressure output, a semicircular or square pressure stabilizing chamber is usually welded inside the double bottom on the outer plate of the bottom of the ship. When the ship is moored at the dock or encounters severe sea conditions during navigation, the ship's air layer drag reduction system will be shut down. At this time, seawater will enter the pressure stabilizing chamber from the jet hole and carry marine organisms into the pressure stabilizing chamber. Since seawater is corrosive, it will corrode the hull steel plate and the pressure stabilizing chamber. If it is immersed in the seawater environment for a long time, it will cause corrosion and cracking of the pressure stabilizing chamber and the bottom plate, thereby affecting the structural safety of the ship.

[0004] The pressure stabilizing chamber is a Φ168*20.0 semicircular tube, which is in direct contact with seawater. Although the semicircular tube of the pressure stabilizing chamber is made of a special steel tube containing 1% chromium, in order to further protect the semicircular tube and the thickened outer plate, the inside of the pressure stabilizing chamber still needs to be painted. The space inside the pressure stabilizing chamber is small, and it is welded on the thickened outer plate, so conventional phosphating, galvanizing and other treatment methods cannot be used. Due to the small space, personnel cannot enter, so special sandblasting and painting equipment is required for sandblasting and painting inside the pressure stabilizing chamber. According to the characteristics of the pressure stabilizing chamber, sandblasting and painting equipment is designed for sandblasting and painting. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a sandblasting method, aiming to shorten the overall construction period to the greatest extent and improve the construction quality. The technical solution adopted is: The main body of the sandblasting device is a sandblasting tube, which has two bends, both of which are 90° and opposite in orientation. The front end of the sandblasting tube is connected to a sandblasting nozzle through a sandblasting nozzle holder, and the rear end of the sandblasting tube is connected to a sandblasting machine; the overall height of the sandblasting trolley is less than the radius of the pressure stabilizing chamber; A tube holder is arranged below the sandblasting tube. The tube holder is an arc-shaped groove that is concave downwards. The sandblasting tube is embedded in the arc-shaped groove. A plurality of sets of running wheels are arranged at the bottom of the tube holder. Each set of running wheels has two pulleys, and the two pulleys are symmetrically arranged on both sides of the tube holder.

[0006] The specific sandblasting process is: The rear end of the sandblasting tube is connected to the sandblasting machine, and a traction rope is installed at the front end of the sandblasting machine. The sandblasting tube is placed into the pressure stabilizing chamber from one end of the sealing box. The front end controls the speed forward through the traction rope, and the rear end sprays sand through the sandblasting machine to grind the inside of the pressure stabilizing chamber. The polished sand will be directly ejected through the jet holes under the pressure stabilizing chamber. The sandblasting trolley enters from the sealing box at one end of the pressure stabilizing chamber and exits from the other side.

[0007] In the above-mentioned sandblasting method, further, the sandblasting trolley is supported by two tubes, and two sets of running wheels are arranged at the bottom of the tube, and the distance between the two sets of running wheels and the edge of the tube is greater than 300 mm.

[0008] In the above-mentioned sandblasting method, further, a concave fixing sleeve is arranged above the tube holder, the edge of the ferrule is surrounded by the tube holder, prototype openings are arranged at corresponding positions of the tube holder and the ferrule, and the tube holder, the ferrule and the sandblasting tube are fixed together by fixing screws 7.

[0009] In the above-mentioned sandblasting method, further, the width of the traveling wheel is close to the width of the pressure stabilizing chamber.

[0010] In the above-mentioned sandblasting method, further, the diameter of the sandblasting tube infinitely approaches half of the radius of the pressure stabilizing chamber.

[0011] In the above-mentioned sandblasting method, further, the sandblasting nozzle and the sandblasting nozzle holder are spirally mounted and can be replaced.

[0012] The present invention utilizes a sandblasting trolley to solve the problem of sandblasting in a narrow space. It is a key equipment in the air layer rent reduction system. The walking wheels ensure that the sandblasting trolley can sandblast in a narrow space, polish the inside of the pressure stabilizing chamber, shorten the sandblasting cycle, and realize unmanned sandblasting in a narrow space. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the sandblasting trolley; Figure 2 It is a schematic diagram of the structure of the sealing box; Among them, 1-sandblasting tube, 2-sandblasting nozzle, 3-fixed sleeve, 4-sandblasting nozzle holder, 5-traveling wheel, 6-tube holder, 7-fixing screw. DETAILED DESCRIPTION

[0014] The present invention will be further described in conjunction with the accompanying drawings.

[0015] A sandblasting method such as Figure 1 As shown, the sandblasting trolley has a sandblasting tube 1, a sandblasting nozzle 2 is arranged at the front end of the sandblasting tube, and the rear end is connected to the sandblasting machine. Due to the sandblasting volume requirement, the diameter of the sandblasting tube should be as large as possible, but not more than half of the radius of the pressure stabilizing chamber.

[0016] The sandblasting tube has two bends with a bending angle of 90°. The orientations of the two bends are opposite, and the overall height is not greater than the radius of the pressure stabilizing chamber. The reason for setting the bends is to avoid excessive sandblasting pressure, which may cause the sandblasting tube to fall off.

[0017] A pulley tube 6 is arranged under the sandblasting tube, so that the sandblasting device can move forward in the pressure stabilizing chamber, and two sets of running wheels are arranged on the pulley tube 6.

[0018] The sandblasting nozzle is fixed by a sandblasting fixing sleeve 3, and two sets of fixing screws are installed laterally on the sandblasting fixing sleeve. The maximum width of the walking wheel is not greater than the radius of the pressure stabilizing chamber and should be as close as possible to ensure that the walking direction of the entire trolley is not offset.

[0019] Sandblasting process: The rear end of the sandblasting tube 1 is connected to the sandblasting machine. A traction rope is installed at the front end of the sandblasting machine. The sandblasting tube is placed into the pressure stabilizing chamber from one end of the sealing box. The front end controls the speed forward through the traction rope, and the rear end sprays sand through the sandblasting machine to grind the inside of the pressure stabilizing chamber. Since the pressure inside the pressure stabilizing chamber is very high, the polished sand will be directly sprayed out through the jet holes under the pressure stabilizing chamber. No secondary treatment is required, and only the paint spray holes need to be cleaned. The sandblasting trolley enters the sealed box at one end of the pressure stabilizing chamber and exits from the other side. The sealed box is as shown in the figure. Figure 2 As shown in the figure, the sandblasting head is a consumable part and can be replaced according to the size of the sandblasting.

Claims

1. A sandblasting method, characterized in that: The main body of the sandblasting device is a sandblasting tube (1), which has two bends, both of which are 90 degrees and have opposite orientations. The front end of the sandblasting tube is connected to a sandblasting nozzle (2) through a sandblasting nozzle holder (4), and the rear end of the sandblasting tube is connected to a sandblasting machine; the overall height of the sandblasting trolley is less than the radius of the pressure stabilizing chamber; A trustee (6) is arranged below the sandblasting tube. The trustee is in the form of a downwardly concave arc groove. The sandblasting tube is embedded in the arc groove. A plurality of groups of running wheels (5) are arranged at the bottom of the trustee. Each group of running wheels has two pulleys. The two pulleys are symmetrically arranged on both sides of the trustee. The specific sandblasting process is: The rear end of the sandblasting tube is connected to the sandblasting machine, and a traction rope is installed at the front end of the sandblasting machine. The sandblasting tube is placed into the pressure stabilizing chamber from one end of the sealing box. The front end controls the speed forward through the traction rope, and the rear end sprays sand through the sandblasting machine to grind the inside of the pressure stabilizing chamber. The polished sand will be directly ejected through the jet holes under the pressure stabilizing chamber. The sandblasting trolley enters from the sealing box at one end of the pressure stabilizing chamber and exits from the other side.

2. A sandblasting method according to claim 1, characterized in that: The sandblasting trolley is supported by two tubes, and two sets of running wheels are arranged at the bottom of the tubes. The distance between the two sets of running wheels and the edge of the tubes is more than 300mm.

3. A sandblasting method according to claim 1, characterized in that: A concave fixed sleeve is arranged above the trustee, the edge of the ferrule is surrounded by the trustee, prototype openings are arranged at the positions of the trustee and the ferrule, and the trustee, the ferrule and the sandblasting tube are fixed together by fixing screws 7.

4. A sandblasting method according to claim 1, characterized in that: The width of the traveling wheel is close to the width of the pressure stabilizing chamber.

5. A sandblasting method according to claim 1, characterized in that: The diameter of the sandblasting tube is infinitely close to half of the radius of the pressure stabilizing chamber.

6. A sandblasting method according to claim 1, characterized in that: The sandblasting nozzle is spirally mounted on the sandblasting nozzle holder and can be replaced.

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