Electric Water Heater Inner Tank Production Line Metal Shot Blasting Machine

01  Main technical specification and requirement:

1. Applicable workpiece size and type: inner tank length: 350-1100mm, inner tank diameter: Ø300- Ø410mm

2. Production capacity: 120 pieces/hour

3. Work room size: L4500*W1500*H3100MM (as real design shall prevail)

4. POWER SOURCE: 380V/50HZ

5. POWER: ≤28kw/set (excluding air compressor power)

6. Using compressed air supply air pressure: 0.5-0.7mpa;Gas supply flow: 36m3/min

7. Except embroidery grade: Sa2.5 (gb8923-88)

8. Diameter and number of nozzles: three nozzles, 4 nozzles/set

9. Applicable steel sand type: steel sand

10. Applicable steel sand particle size: 0.5-1.20mm

11. Steel sand automatic recovery, sorting, recycling use

12. Sandblasting operation: suspension chain automatic operation + manual sand cleaning.

13. Operator: 2 persons/set

02  Safety measures and environmental protection:

1. Personal safety guarantee measures

Sandblast door and sandblast operation interlocking：Sand blasting can be carried out only when the door of the sandblasting box is closed.

2. Safety of equipment operation

2.1 Ventilation and dust removal system and sand blasting operation start button interlock: only after the ventilation and dust removal system works normally, sand blasting operation can be carried out.

2.2 Protective covers shall be set up for each mechanical operation part in accordance with the general specifications

3. Environmental protection:

Environmental protection issues include industrial dust, vibration and noise.

3.1 Industrial dust emission

Set up the ventilation and dust removal system, discharge concentration ≤120mg/m3. discharge rate≤3.5Kg/h

3.2 Vibration

The main equipment for vibration of the whole system is draught fan, and the measures to solve the vibration is as follows: the vibration reduction device, sound insulation room and vibration reduction pipe are prepared for draught fan.

3.3 Noise

There are two types of noise: the first is fan noise, the solution is to choose a low noise fan and silencer; The second kind of noise is the air dynamic noise at the nozzle outlet and the impact of steel sand on the workpiece when sandblasting. The countermeasures is sandblasting process in a closed box to reduce the noise.

03  Working principle and process:

1. Working principle of the system (see the following principle block diagram) : after the workpiece is placed on the working table and positioned through the stepper suspension chain, the door of the sandblasting box is automatically closed, the movement mechanism of the gun and the working mechanism move separately, and the sandblasting machine sandblast steel sand. Ejected steel shot back to sandblasting sand box, by the horizontal screw mechanism sand material to flow into the vertical screw mechanism, the vertical screw mechanism will sand material into sand material upgrade system (sand dust by the physical separation), hoist will increase sand material to store material in the box, the sand valve automatic control into the sand blasting machine, sand material recycling.

2. Technical process

2.1 Workpiece sandblasting process: start the compressor → open hanging chain, →artificial pieces → start the dust removal fan→ when the pressure reaches more than 0.4 Mpa, start sandblasting machine according to the requirement →automatic opening sandblasting door→ artifacts on the workstation by suspension chain → automatically close sandblasting door→ spray gun start automatic lifting, rotating → automatically sandblasting → after sandblasting → the sandblasting door is opened automatically → taking it from hanging chain - artificial soot cleaning operations.

2.2 Technological process of steel sand recovery: the steel sand ejected falls back to the sand bucket (receiver) of the sandblasting box→ the steel sand conveying pipe →the sand (spiral conveying mechanism)→ the storage box→ the pneumatic feeding valve→ the sandblasting machine

2.3 Dust treatment process: dust produced during sandblasting operations → sandblasting box collection bucket (receiving device)→ steel sand transport pipe→ sand (spiral transport mechanism)→ dust pipe→ filter cartridge dust collector→ fan→discharged into the atmosphere

04  Introduction of system functions and equipment composition:

The complete set of equipment consists of sandblasting box, sandblasting machine, steel sand recovery system, dust removal system, air control system, electronic control system and other parts.

1. Sandblasting box

It is an enclosed space, the skeleton is made of section steel , steel plate is used as the wall, 3mm wear-resisting rubber board (imported rubber) is pasted around the inner wall and the top, and the outer wall is decorated with cold plate edges.

A manual door is set on the side of the box body, which is the passage for the workpiece to enter and exit and for maintenance. Only when the door is closed (except when the single machine is debugged) can sand blasting be carried out. A glass (tempered glass) observation window is set on the operating surface of the box body to facilitate workers to observe the operation status of sandblasting box. A high illumination lamp is set at the top of the box body to illuminate the sandblasted box through glass (tempered glass).In order to remove the dust and steel sand generated in time, a sand collecting hopper and a dust and sand suction port are arranged at the bottom of the sandblasting box.

2. Sandblasting machine

It’s made of sandblasting machine, sandblasting pipe, nozzle composition. It is the main equipment to complete sand blasting and rust removal. Sand blasting machine working according to principle is divided into two categories of pressure type and suction type. Because the pressure type is in the same pressure vessel to make steel sand and compressed air fully mixed after injection, so that the compressed air is fully used. Because air flow and steel sand flow are easy to adjust, can get the ideal mixing ratio, so it is high efficiency, low energy consumption, steel sand consumption is also small, especially suitable for large area surface cleaning. This project adopts the pressure type sand blasting machine.

2.1 Equipment configuration

Using Spxx01-2r pneumatic sand blasting machine. This machine is specially designed for direct pressure box type combined sandblasting machine, especially suitable for steel sand occasions.

2.2Its advantages include:

(1) It is easy to adjust the flow rate of compressed air and sand output, and to configure nozzles of different types and diameters to meet different requirements;

(2) Quickly response, easy to open, easy to operate, remote control operation;

(3) Cemented carbide sandblasting valve is adopted, with low failure rate, less vulnerable parts and long service life.

(4) Piston pneumatic air valve is adopted, which has lower failure rate, less vulnerable parts, long service life and more accurate and quick action than the traditional diaphragm air valve;

(5) The nozzle made of hard alloy has a hardness of over 85HRA.

3. Steel sand recovery system

The steel sand conveying device is used to send the rust, oxide scale, impurities and broken steel sand cleaned down from the sandblasting box collecting hopper to the steel sand purification device and the storage box for storage.

This solution adopts pneumatic conveying steel sand recovery method. When working, the steel sand and certain dust ejected from the gun can be absorbed at the same time. It shares a power source and dedusting equipment with the dedusting system.

Equipment supporting: by receiving device, feeding pipe, storage box, feeding valve, storage box bracket and other components. Steel sand conveying pipe adopts wear-resisting corrugated rubber pipe. When the mixture of dusty air and steel sand (steel sand after use and supplementary steel sand) is under the action of the fan, it passes through the steel sand conveying pipe to the cyclone separator. The dusty air and the steel sand are separated by centrifugal separation. After separation, the steel sand enters the material storage box for storage, and the dust enters the dust removal system for treatment.

4. Spray gun movement mechanism

The sandblasting gun is driven by the motor to do vertical linear motion, and the motor frequency conversion speed regulation, it can be stepless speed regulation (0-1.5m/min) under the maximum speed limit to apply to different workpieces. Height: about 0-1100mm (according to drawing)

Equipment: motor, reducer, transmission mechanism, linear guide rail, gun fixed platform, etc.

System design principles:

5.1 Design principles

A. The natural air supply from the upper part and the exhaust from the lower part are adopted, to make the air flow in a reasonable direction, which is conducive to dust transportation.

B. Part of the equipment of steel sand recovery system and dust removal system is Shared.

C. The principle of equipment configuration is reliable application, convenient maintenance, timely supply of vulnerable parts and low operating cost.

D. Considering the foresight and grade of equipment investment.This scheme adopts the high-efficiency submerged flow filter cartridge dust collector which has been used abroad and is popular in China in recent years, so as to ensure that the dust content discharged into the atmosphere under various working conditions conforms to the national environmental protection requirements.

5.2 Form a complete set of equipment

It is composed of air pipe, flow control valve, high pressure centrifugal fan, filter barrel dust collector and so on.

High pressure centrifugal fan is the power source of steel sand and dust transportation. The selection is based on the type of gas transported, system air volume required, air leakage, system pressure loss , working condition, installation mode, noise, energy consumption and other aspects.

The supporting equipment of the dust collector is related to the amount of steel sand conveying, the amount of dust production, the amount of ventilation required by the system and the type of dust. According to the principle of dust collector configuration and theoretical calculation, combined with practice, this dust removal system adopts the first level dust removal mode. The specific equipment is LTC series high efficiency submerged filter cartridge dust collector, which is a new product developed by our company through digest foreign advanced technology .It is characterized by high dust removal efficiency and compact structure. The dust filtration efficiency of 0.5um reaches 99%.Therefore, it is especially suitable for the occasions with extremely high requirements on dust removal efficiency. It has been widely used abroad and has been used and popularized in China. At the same time, in order to use the filter cartridge more effectively and extend the service life of the filter cartridge, the filter cartridge is equipped with pulse back blowing valve and pulse control instrument for regular back blowing.

05  Control system:

Electronic control system: the whole system has two states of normal operation and single machine debugging. When the system is in the single machine debugging state, each device can be controlled independently. When the system is in normal working state, make the equipment act according to the established procedures, and have certain interlocking and protecting functions. Each equipment has good electrical protection, when the equipment failure, can be safe and reliable protection, and automatically stop the lower level of operation and send alarm information, fault discharge and found after the normal instruction, can restart.

The system consists of electric control box, cable and casing. Key electrical components adopt well-known brand products (such as: Schneider, Omron, Shilin, APT, etc.).

Air control system: it is used to control each air control valve and complete automatic operation.

This design scheme is non-standard technical data. In the actual design and production process, the structure size may be slightly different, is a normal technical change, its use effect remains unchanged.