Condenser rubber ball tube cleaning system

Condenser rubber ball tube cleaning system

Introduction to condenser tube cleaning system

Condenser tube cleaning system is a device used to scrub the inner wall of heat transfer tubes of central air-conditioner condenser by physical method.When the central air-conditioner is in refrigeration process,the temperature of the refrigerant rises,so it must be lowered.Cooling water system is the pipeline system used for cooling down the refrigerant and the condenser is the heat-exchange device for cooling refrigerant.Cooling water flows into the condenser through the inner wall of the heat transfer tubes and then flows out.The cooling refrigerant flows through the outer wall of the heat transfer tubes and the condenser exchanges heat by heat transfer tubes,and thus cool down the refrigerant.The cooling water flows into the condenser at a low temperature and flows out at a high temperature after absorbing heat.After operating for a long time,the heat transfer tubes may have incrustation,fouling and stain sediment on inner wall,which may affect the heat transfer efficiency.Small temperature drop of the refrigerant affects the refrigeration effect, increases the load on the host of the central air-conditioner and reduces the life of it,so the inner wall of the condenser heat transfer tubes must be regularly cleaned to extend the life of it.

On-line condenser cleaning system is a kind of equipment used for automatically cleaning the inner wall of the condenser heat transfer tubes on line by physical method when the refrigerating unit is under operation.By injecting and collecting the balls,the system can clean the heat transfer tubes periodically.This system can reduce usage amount of water treatment chemicals,enhance refrigerating efficiency of the unit and save electric energy.

Operating principle of condenser tube cleaning system

To start with the water pump of the condenser tube cleaning system and pump the balls from the ball injector to the water inlet of the condenser with water.The balls enter the end cover of the condenser along with the circulating cooling water and get into the copper tube of the condenser randomly.Driven by the circulating cooling water,the balls move inside the copper tube to scrub the inner wall of the tube.After leaving the tube,the balls get out of the end cover of the condenser with the circulating cooling water and enters the ball collector installed on the outlet pipeline of the condenser.Ball trap in the ball collector then traps the balls,with the water flowing away through the screen.Then the balls return to the ball injector,which means a whole cleaning process is finished.The cleaning frequency and times can be set via microcomputer control program,to realize automatic on-line cleaning. 

Schematic diagram for operating principle of condenser tube cleaning system

Internal schematic diagram for cleaning process

Picture of condenser tube cleaning system

Control mode of condenser tube cleaning system

Automatic control:Set cleaning frequency and times via microcomputer control program,to realize automatic on-line cleaning.

Manual control: Manually start the condenser tube cleaning system.

System composition of condenser tube cleaning system

Ball injector:The container used for storage,injecting and collecting balls.The installation position of the ball injector and the inlet and outlet connecting pipes shall ensure that the balls are even without blockage. 

Ball collector:When the balls leave the condenser,they’ll be caught by the ball collector.The chamber material is carbon steel or stainless steel,the max working pressure is 10-25 bar,the effective open area is greater than 3 times of that of the connecting pipe and the hydraulic resistance loss is less than 5 Kpa.The ball collecting screen shall be designed with good hydraulic characteristics to prevent the screen from vibrating under the impact of water flow.The design of the ball collecting screen shall ensure no blocking or slipping of balls. 

Sponge balls:Used for cleaning inner wall of the condenser heat transfer tubes.The balls shall have uniform density and good recoverability.When the balls work at a water temperature of 5-36 ℃,the diameter of wet balls shall not be larger than 0.5 mm of dry balls.During the operation,the diameter of the balls shall be 1-2 mm larger than the inner diameter of the heat transfer tubes.The balls shall remain stable during the operation to prevent the blocking of cooling water pipe.

Specification for balls and adaptive inner diameters of copper tube to be cleaned

Microcomputer controller:Automatically control and set cleaning frequency and time.It can also be set according to temperature difference of the water getting in and out of the condenser to trigger cleaning.

Problems resulted from scaling in copper tube of condenser

Scaling on tube wall reduces the surface heat transfer efficiency and affects the heat transfer coefficient of tube

After using the condenser tube cleaning system, the heat transfer coefficient of tube can be maintained at the system initial state. 

1 mm thick accumulated scaling in tube of condenser will increase 30% of energy consumption.

After using the condenser tube cleaning system,the host energy consumption can be maintained at a utilization of 100%

Functions of condenser tube cleaning system

Improve operating efficiency 

Since condenser tube cleaning system that enables copper tube of condenser to get rid of scaling and operation of compressor will not exceed the design limit,the central air-conditioner can operate at its optimum efficiency.

Extend service life of central air-conditioner and reduce maintenance

Since operation of compressor will not exceed its design limit, life of equipment is extended, and thus effectiveness and investment return of the central air-conditioner are enhanced. Yet certain maintenance is still necessary.

Reduce overall energy consumption
When the compressor operates at the maximum power,the central air-conditioner can generate the same output by consuming less energy.In a typical case,the energy saving department of a semiconductor manufacturer audited the condition before and after installing the condenser tube cleaning system for a 800 tons central air-conditioner and found that it saved energy amounting to 83,000 USD every year by using condenser tube cleaning system and investment payback period is 4 months.

Reduce the cost of water treatment

Since the condenser tube cleaning system enables the copper tube of the condenser to get rid of scaling,the water treatment just needs some auxiliary equipment to prevent scaling,such as cooling tower and valves,etc.An independent audit of manufacturer found that,after installing the condenser tube cleaning system,the cost of the chemicals used for treating water had reduced by 51%.In another audit of a commercial building with two 300 tons central air-conditioners,the total hardness and total dissolved solids had reduced by 51% and 53% respectively.

Prevent corrosion of condenser tube

Microbiological corrosion and centralized cell corrosion results from scaling on tube wall.Since the condenser tube cleaning system can prevent tube scaling,these corrosion mechanisms will be eliminated,thus extending the service life of the tube. 

Comparison between condenser tube cleaning system and traditional descaling methods

Benefit analysis of condenser tube cleaning system
For instance,there is a central air-conditioner with 3 chillers,each of which has a compressor power of 429KW and operates throughout the years.In summer,all three chillers will be under operation,with a total compressor power of 1287 KW and an operation time of 4 months.In other seasons,two chillers will be under operation,with a total compressor power of 858 KW and an operation time of 6 months.Since water quality varies in different regions,the energy saving effect is various between 15%-35%.Assume the energy saving rate is 0%,the average load is 80%,the chillers operates for 24 hours per day and 30 days per month and the electric charge is RMB 1.0 per kw/h,
Then: The electric charge saved per month in summer is:
1287 kW×80%×1 h×1.0 RMB/ kw/h×20%×24 h×30 days= RMB 148262.4.
And the electric charge saved per month in other seasons is:
858 kW×80%×1 h×1.0 RMB/ kw/h×20%×24 h×30 days= RMB 98841.6.
The electric charge saved in the whole year is:
RMB 148262.4×4 months +RMB 98841.6×6 months=RMB 1186099.2
In addition,the total economic benefit reaches as much as 1.2 million yuan per year,including the expenses on chemical cleaning,labor and equipment maintenance,and calculated at an available machine year of 10 months per year.As it turns out,the user can recover the investment cost of the equipment in a short time.

Features of condenser tube cleaning system

1. The host of condenser tube cleaning system integrates the water pump and ball injector,saving space and covering less area.

2. It’s easy to operate.The cleaning can be finished by controlling the start and stop of the water pump by time,and the cleaning time,interval and frequency can be set.

3. The ball collector is equipped with a water flow switch.When the circulating cooling water stays still,the water pump of the cleaning device cannot rotate,which prevents the water pump from operating without water.

4. The ball collecting screen applies stainless steel screen with large mesh size,which only traps the balls and has low water resistance.

5. The balls only circulate in the pipeline and do not go through water pump,which can prevent the pump impellers from hitting the balls and extend the service life of the balls. 

6. The operating cost is low and the sponge balls are the only consumables.

Comparison before and after using the condenser tube cleaning system