Common faults and solutions for three-purpose work ship bulk air compressors Li Zhanjun three-purpose work ship bulk air compressor common faults and solutions Li Zhanjun (China Petroleum Group Marine Engineering Co., Ltd. Marine Division Tianjin 300451) using bulk air compressor The pressure energy of the compressed air is turned into kinetic energy to achieve the purpose of conveying the target and mixing uniformly. Therefore, the reliable operation of the bulk air compressor becomes an important guarantee for the operation of the bulk material conveying system.

1 Introduction to bulk material conveying system and working principle of bulk material air compressor 1.1 Introduction to bulk material conveying system The most important material handling system for ocean engineering ship (AHTS, PSV, etc.) is mainly for the supply of powder materials required for drilling on offshore platforms. Domestically, it is often called the ash conveying system. The system uses a gas-solid two-phase flow technology to realize long-distance, closed and efficient transportation of powdery materials between onshore base stations, offshore engineering vessels and offshore platforms. The state exhibited by this gas-solid two-phase flow system is generally said to be fluidized, and the gas-solid two-phase fluidization theory is the basis of the pneumatic conveying technology of powdery materials.

1.2 Operating principle of bulk material conveying system.

The pneumatic conveying of the powdered material is to change the pressure energy of the compressed air provided by the air compressor into kinetic energy, and carry the powdery material for complex movement, so that the position of the material particles is continuously changed to achieve the intended conveying target and uniform mixing. At present, the technology has been widely used at home and abroad, equipped with nearly a thousand types of marine engineering vessels and cementing bulk cement base stations distributed around the world. The operation mode of bulk material conveying system is divided into loading operation and unloading operation: the loading operation is to directly send the bulk material into the bulk ash tank for storage by the compressed air on the shore base station or offshore platform; the unloading operation is to use the ship's own compression. The machine transports the contents of the tank to the offshore platform. The bulk tank has a specially designed tank bottom and fluidization device, which can fully fluidize the material in the tank and discharge it from the discharge pipe. The onboard compressor not only provides a power source for the entire process, but also a function of assisting the blowing and compressed air sweeping.

The bulk material conveying system is organically combined with each other and is engaged in various ship management tasks.

Different process pipelines, valve components, sensors, meters, etc. are effectively connected to install corresponding electronically controlled pneumatic valves and electronically controlled proportional valves on each pipeline. The remote control system arranged behind the bridge can monitor and control the operation of each equipment. .

1.3 Bulk material conveying medium and application occasions 1) The transport medium is: cement, bentonite, barite powder, limestone, kaolin, fly ash. Its material density: less than or equal to 2.8T/Msup3; its particle size is between 2 2) system applications include: offshore oil three-purpose work boat, platform supply ship, offshore drilling platform, bulk cement ship, land-based bulk ash station .

2 Marine Bulk Air Compressor Introduction 2.1 Basic Structure and Working Principle of Screw Compressor 1) Basic Structure: In the body of the compressor, the parallel arrangement * pairs of helical rotors that mesh with each other. A rotor having a cam outside the pitch circle is generally referred to as a male rotor; a rotor having a concave tooth in the pitch circle is referred to as a female rotor. Generally, the male rotor is connected with the prime mover, and the male rotor drives the female rotor to rotate. The ball bearings on the rotor position the rotor axially and withstand the axial forces in the compressor. Cylindrical roller bearings at both ends of the rotor position the rotor radially and withstand the radial forces in the compressor. At both ends of the compressor body, openings of a certain shape and size, one suction port and one exhaust port are respectively opened; 2) Working principle: the working cycle of the screw compressor can be divided into three parts: suction, compression and exhaust. process. As the rotor rotates, each pair of intermeshing teeth successively complete the same duty cycle. The compression of the gas is achieved by a change in volume, which is achieved by the rotary motion of the rotor in the casing by means of the compressor. As long as the suction and exhaust orifices are properly arranged on the casing, the suction, compression and exhaust processes of the compressor can be realized.

2.2 Characteristics of Screw Compressor The screw air compressor is selected for marine bulk air compressor. Its advantages are: high reliability, convenient operation and maintenance, good dynamic balance, strong adaptability and multi-phase mixed transmission. The disadvantages are: high cost, can not be used in high pressure, can not be made into miniature.

2.3 Atlas brand air compressor model is known as the Zhongyouhai 282 ship, which uses Atlas GA160W-7.5 screw air compressor, G series represents fuel injector, A represents single-stage compression 160 represents a power of 160 kW, W stands for water cooler, and 7.5 stands for maximum working pressure.

3 Common failures and troubleshooting methods of air compressors 3.1GA rotor outlet temperature is too high 1) Fault phenomenon: The unit is not well cooled and the oil supply temperature is high. The cause of the fault and the solution: poor ventilation (need to adjust the installation site or hot air treatment); poor heat exchange of the cooler (cleaning required); oil circuit problem (check thermostatic valve); 2) less oil supply. The cause of the fault and the solution: less oil storage (addition or replacement of oil); oil shut-off valve stuck (requires disassembly); oil filter blocked (replacement filter required); oil flow rate is slow (requires inspection of ambient temperature) ).

3.2 The air compressor does not load after starting operation 1) Fault phenomenon. Solve the problem that the solenoid valve is not working or malfunctioning: check whether the power is available, remove or replace the solenoid valve; 2) the intake valve cannot be opened (may be due to the valve member stuck or the seal leaking). Solution: repair valve parts or replace seals; 3) control air pipe leakage solution: replace control air pipe; 4) minimum pressure valve air leakage solution: repair.

3.3 The air compressor is not unloaded, the safety valve jumps 1) The solenoid valve loses control. Solution: Repair or replace the solenoid valve; 2) The intake valve is not closed. Solution: Disassemble the machine; 3) Computer failure. Solution: You need to replace the computer.

3.4 When the unit is loading and running, there is no condensed water discharge. 1) The drain hose is blocked: Solution: Check and repair the corresponding parts, 2) The water delivery valve loses its function: Solution: Dismantling and repairing; 3) If the electronic water delivery valve fails There may also be a circuit failure. Solution: Check the circuit condition.

3.5 Compressed air does not reach normal pressure failure phenomenon: 1) Air consumption exceeds gas production. Solution: Check air line and gas equipment; 2) Air intake is blocked. Solution: Clean or replace the air filter; 3) The solenoid valve is out of control. Solution: Replace the solenoid valve; 4) Control the leakage of the compressed air tube. Solution: Check or replace; 5) The valve cannot be fully opened. Solution: Maintain the intake valve; 6) The oil separator core is blocked. Solution: Replace the separator heart f 7) The exhaust line system is blocked. Solution: Check each unit on the pipeline, including: valve, filter, dryer; 8) outlet pressure sensor failure. Solution: Replace the sensor; 9) The rotor has failed. Solution: Repair or replacement; 3.6 After the shutdown, there is too much oil coming out of the air filter 1) The check valve leaks. Solution: Replace the damaged parts; 2) The oil stop valve is stuck. Solution: Repair and repair, replace damaged parts; 3) Intake valve is not dead. Solution: Maintain the intake valve.

3.7 The safety valve jumps after the unit is loaded. 1) The exhaust valve does not open. Solution: Open the exhaust valve before starting; 2) Intake valve or minimum pressure valve failure. Solution: Check the intake valve and minimum pressure valve; 3) Block the oil separator core. Solution: Replace the separator heart f 4) The ice dryer is blocked. Solution: Repair the dryer; 5) The safety valve is broken. Solution: Replace the safety valve; 4 routine maintenance 4.1 maintenance purposes The key factors affecting the life of the air compressor are: product design and quality; air compressor installation and commissioning; daily maintenance and regular maintenance.

A unique maintenance system guarantees the most efficient operation and lowest operating costs of air compressors, preventing malfunctions (down to page 46), moistening the surface of the coal, isolating oxygen contact, and preventing the adsorption of oxygen on the coal surface.

3.7 New Gel Foam Type Inhibitor The new gel foam inhibitor has the dual advantages of gel and foam inhibitor. The inhibitor is formed by mechanical foaming of a solution of a surfactant, a crosslinking agent and a polymer. After the foaming, the gelling agent in the foam wall undergoes crosslinking reaction under the action of the crosslinking agent to form a gel. The gel is mainly composed of a network structure and a liquid which is surrounded by the film. The film has good stability and has solid and liquid properties; the liquid in the gel body can flow in the gel body and has the property of liquid material. The foam has a large surface area, is highly stackable, has three-dimensional flow characteristics, and can diffuse and fill larger areas and spaces. However, the simple gel has poor fluidity, small flow and diffusion range, and the foam is easily broken. The advantages of the new gel foam combined with gel and foam make up for the shortcomings of both, and improve the efficiency of fire prevention and fire extinguishing.

Through the analysis of the above commonly used inhibitors, the inhibitors of each inhibitor are shown in Table 1. The resistance mechanism of each inhibitor is the type of resistance mechanism. The moisturizing oxygen-diluting oxygen-covered active center reduces the functional group and reduces the free radical chain reaction chloride salt. The new type of high-polymer foam type gel-like gel of the ammonium-like base type colloids can be seen from the above analysis. Most of the inhibitors can only control the spontaneous combustion of coal from a certain aspect, and have certain certain effects in prevention and extinguishing. Limitations, and some inhibitors can corrode the hull, posing a hidden danger to the safety of the ship. When the inhibitor does not affect the resistance of a certain factor affecting coal spontaneous combustion, the coal will still spontaneously ignite under the influence of other factors.

(Continued from page 28) occurs, keeping the device in optimal operating condition.

4.2 Daily maintenance work 1) Cleaning work: cleaning of the main motor fan blade and heat sink, cleaning of the cooler, cleaning of the steam trap, cleaning of the oil respirator, cleaning of the air filter, electrical control box Cleaning work inside; 2) Timed discharge of condensed water: ZR machine's medium and cold cold trap, GA air cooler water heater, FD steam trap, MD comprehensive comparison, new gel foam resistance Chemical energy can well control the various influencing factors of coal spontaneous combustion, both physical and chemical aspects have achieved resistance, effectively prevent the occurrence of spontaneous combustion of coal, and will not corrode the hull and apply harmful gases, can be very good Suitable for shipping coal to prevent spontaneous combustion requirements.

4 Summary The use of inhibitors is inseparable from water. Water is the carrier of most inhibitors and fire extinguishing. Through the aqueous solution, the inhibitor can be poured or sprayed on the surface of the floating coal. However, the impact of the aqueous solution should be evaluated when the ship is used to avoid fluidization or reduced ship stability. In the selection of inhibitors and fire extinguishing, coal with different spontaneous combustion tends to have different structural characteristics and the number, type and molecular structure of active groups on its surface. There are few studies on how to choose the inhibitory agent and the inhibitor concentration to achieve the best resistance effect for different coal types. It is hoped that through the author's throwing bricks, more research on the use of marine inhibitors and the effects of different coal species inhibitors will be drawn.

Sup Paddle Board

Sup Paddle Board,Inflatable Surfboard,Inflatable Paddle Board,Inflatable Stand Up Paddle Board

Ningbo Haishu Hongkang Outdoor Industry & Trade Co., Ltd , https://www.hktrollingmotors.com