TopChiller Screw Compressor Chiller Manufacturer and Supplier China

Screw Compressor Chiller-an Ultimate Buying Guide by TopChiller.

The Screw Compressor Chiller is used for both industrial and commercial applications where a high amount of cooling capacity is required.

In HVAC, all the high-rise buildings whether industrial, residential, or commercial always go for a screw-type chiller with greater reliability, energy-saving, and cooling efficiency.

The Screw Compressor Chiller is an excellent cooling system to install where a high amount of cooling source is required.

In this guide, we are going to present all the necessary information about it.

Let’s start it.

What is a Screw Compressor Chiller?

A Screw Compressor Chiller is an industrial chiller equipped with a screw-type compressor.

Similar to other refrigeration systems, a Screw Compressor Chiller is also composed of a screw compressor, an evaporator, a condenser, and an expansion valve.

A Screw Compressor Chiller is unique because of its compression technique. Its screw compressor uses double-helical rotors that are responsible for propelling and compressing the refrigerant vapor.

Its compressor has few moving parts that’s why it is quiet, lightweight, and durable.

A Screw Compressor Chiller is widely used in a variety of applications that need efficient and durable cooling services. It performs very well during harsh weather conditions.

It has large refrigeration power, stable and simple operation, a wide application range, and a compact design and structure. Screw Compressor Chiller can be a water-based or an air-based refrigeration system.

Screw Compressor Chiller Designed by TopChiller

What are the Main Features of a Screw Compressor Chiller?

Following are the features of the Screw Compressor Chiller:

1. The microcomputer controls the fully automatic function and precise temperature.
2. The PLC system is used to control the system of Screw Compressor Chiller, a larger touch screen display that is easy to adjust various settings.
3. Low space is required to install it.
4. Less energy is consumed because of its screw-type compressor.
5. It runs very efficiently and has lesser spare parts.
6. The Screw Compressor Chiller can be cooled by injection because it is not sensitive to the liquid inlet.
7. The discharge temperature of the Screw Compressor Chiller is very low as compared to another chiller at the same pressure.
8. There is no clearance volume in Screw Compressor Chiller. This further increases its efficiency and efficacy.
9. Smaller vibration of the machine base while operating is another salient feature of it.
10. The Screw Compressor Chiller never over-cools and efficiently perform according to the capacity of the building.

Screw Compressor Chiller PLC System

What are the Main Components of Screw Compressor Chiller?

The followings are the main components of a Screw Compressor Chiller;

1. Screw Compressor

Screw Type Compressor plays a very important role in Screw Compressor Chiller.

It is a prime mover, creates pressures difference to circulate the refrigerant all around the system. It is placed between the evaporator and the condenser.

2. Condenser

It is used to remove the heat carried by the refrigerant in the evaporator. A condenser may be water-cooled or air-cooled.

It is found after the compressor and before the expansion valve of the system.

3. Evaporator

An evaporator is used to collect the heat from your application ad move it into the refrigerant.

It further sends it to the cooling tower to dissipate into the air. It is located between the compressor and the expansion valve.

4. Expansion Valve

This component is responsible for expanding the refrigerant by reducing its pressure to allow the unwanted heat to pick up in the evaporator.

It is placed between the condenser and the evaporator of the Screw Compressor Chiller.

5. Power Panel

This unit is responsible for controlling the flow of electric current through different components.

It includes circuit breakers, starters, and speed controller devices.

6. Control Unit

This unit inspects the performance of the whole system and controls adjustments as required.

The control unit is capable of generating alarms if any irregular activity is found.

Screw Compressor Chiller Compressor

How does Screw Compressor Chiller work?

A Screw Compressor Chiller functions as follows.

Step 1:

First of all, the gas refrigerant from the evaporator of the Screw Compressor Chiller is compressed by a screw compressor.

Step 2:

After that, in the screw compressor, it attains the state of high-pressure gas with extremely high temperatures.

Step 3:

The condenser then cools the compressed refrigerant gas without disturbing its pressure.

The condenser can be an air-cooled type or water-cooled type.

Step 4:

After the condensation of this gas, it changes its state into liquid. This liquid is further expanded to low pressure with the help of an expansion valve.

Step 5:

This gas-liquid mixture is found, the low pressure and low-temperature liquid refrigerant absorb the heat from your application.

Step 6:

It becomes the gaseous refrigerant again to circulate again by entering the compressor.

What are Single Stage and Double Stage Compressions in a Screw Compressor Chiller?

The air is compressed many times between the inlet valve and the tool nozzle is the main point that distinguishes between single-stage and two-stage compressors.

In a single-stage compressor, as the name suggests, the air undergoes compression once whereas, in double stage compressor, the compression of air occurs twice.

Single-stage compressors are also called piston compressors. The procedure that is followed inside the single-stage compressor:

• The cylinder sucks in the air.
• This air is then compressed in a single stroke at around 120 psi.
• The compressed air is then pushed and sent to the storage tank.
• In the storage tank, this air is used as energy for the tool assortment that a single-stage compressor is built to accommodate.
• The single-stage compressor resembles a two-stage compressor in many aspects but there exist some differences between them and that is:
• Instead of sending a storage tank, the compressed air is sent to a piston smaller in size at roughly 175psi for a second stroke.
• This compressed air is then cooled and sent back to a storage tank.
• Here, it is used as energy for high-powered equipment.

Single-stage air compressors can be easily transferred from one room to another due to their smaller size.

On contrary, multi-stage compressors are typically heavier and larger.

In a single-stage compressor, all of the cylinders are relatively small and have their inlet valves.

On the other hand, in a double-staged compressor, there is only one inlet.

How is Screw Compressor Chiller Different from other Chillers?

Screw Compressor Chiller is composed of an evaporator, compressor, condenser, expansion valve just like all other chillers.

Compressor Type:

A Screw Compressor Chiller uses two rotating helical screws that provide adequate pressure required for driving the vapor-compression refrigeration process.

Increased Durability:

It is more durable and quieter because of a smaller number of moving parts.

Compact Size:

Screw Compressor Chiller is the popular choice of consumers because of its lighter weight and small size.

Heavy-Duty Performance:

Screw Compressor Chiller is very reliable and can be used in harsh conditions.

Mostly used air compressors are either reciprocating piston type or rotary screw type.

Reciprocating (Piston Type) Chiller

A reciprocating compressor has a piston that moves downward and creates a vacuum by reducing pressure in its cylinder.

The reliability of reciprocating chiller is low and they are more susceptible to breakdown. They are composed of the piston, piston ring, crankshaft, connecting rod, valves, etc.

When the pistons operate, the internal temperature is around 150 to 200C.

There is a lot of space is required by the piston compressor. To overcome its noise and vibration, there is a need for a separate compressor component.

Large machines from 30HP and greater are only water-cooled but small compressors are air-cooled.

Screw Compressor Chiller

On the other hand, screws are used in Screw compressors.

With one side always touching the wall they sit slightly off-center in a shaft.

They achieve a similar goal as reciprocating compressors, as they move at high speed.

There is a male and a female rotor in the Screw Compressor Chiller. The male rotor executes the female rotor.

The basic principle of a Screw Compressor Chiller is based upon the rotation of male and female rotors. As they rotate in an opposite direction, the air is drawn between them.

The volume space between the rotor decreases as the air progresses along with the rotors and the air is compressed, hence creating compressed air that is displaced to the outlet.

Reciprocating (Piston Type) Compressor

What are the Benefits of Screw Compressor Chiller for your Applications?

Convenient Even at the Harshest of Conditions:

Screw Compressor Chiller is appropriate to run as they continuously run air for a required purpose and are also safe to use.

Even in extreme weather conditions, a rotary Screw Compressor Chiller will continue to run. This means that whether there are high temperatures or low conditions, the air compressor will run.

The continuous duty function of a Screw Compressor Chiller means crucial components of the compressor will not deteriorate no matter the condition.

Generate Less Heat Compared to Other Air Compressors:

Screw Compressor Chiller is an energy-efficient option as they generate less heat compared to normal air compressors.

Less heat means less water is created during air compression and water that could get into compressor, tools, and final application is reduced.

The water will then also be easier to remove, as there is less of it.

Enhance Benefits:

To prevent parts from deteriorating, Screw Compressor Chiller has been designed so the compressor oil seals internal rotors.

The design of the Screw Compressor Chiller ensures efficiency for years to come with no or little capacity reduction.

Noise-dampening technology makes it generally quiet despite massive air flows.

Quality components in the Screw Compressor Chiller help to enhance overall productivity.

Simple Maintenance:           

Screw Compressor Chiller is easier to maintain as some of these machines have up to 70% fewer parts which can result in lower maintenance costs.

Maintenance is simple as they feature a rotary-type positive-displacement mechanism that uses fewer materials.

By keeping up with regular maintenance, however, we can keep the compressor running for many years while receiving optimal performance.

What is the Difference between Single Screw Compressor and Double-Screw Compressor Chiller?

• Structure

Single Screw Compressor:

A screw rotor and two symmetrically star wheels.

The screw groove and the inner wall of the casing comprise a closed elementary volume. So that gas can reach the required pressure.

Simple structure and small volume are their characteristics.

Double-Screw Compressor:

The double screw compressor is a double-shaft compressor with a positive displacement. The main pair of male and female rotors cooperate to form a connecting pair.

The tooth profile of the main rotor and auxiliary rotor produces a closed elementary volume with the inner wall of the casing.

• Working Principle

Single Screw compressor:

The motor transmits power to the screw shaft through a coupling. The screw drives the star wheel to start rotation.

The gas begins to enter the screw groove from its suction chamber. The exhaust port and the exhaust chamber compress the gas, and it is discharged.

The role of the star wheel is similar to the piston of a reciprocating piston compressor. When it moves parallel to each other, the enclosed volume is gradually reduced.

Then the gas is compressed.

Double-Screw Compressor:

The motor powers the main rotor through a coupling, belt, or speed-increasing gear.

Under the action of comparative negative pressure, the air is sucked in. The gas is passed and compressed under the anastomosis of the tooth crest and groove.

When the rotor meshing surface turns to communicate with the exhaust port of the casing, the refrigerant that has been compressed is discharged.

• Manufacturing Cost

Single Screw Compressor:

Ordinary bearings can be applied for screw and star wheel bearings. The manufacturing cost is lower.

Double-Screw Compressor:

Due to the relatively large load of the two-screw rotors, bearings with higher accuracy are required. The manufacturing cost is higher.

How to Choose Right Screw Compressor Chiller for your Industry?

Important points that should be kept in mind while selecting the right Screw Compressor Chiller:

1. The important specifications of the Screw Compressor Chiller are the refrigeration performance coefficient, input power, the cooling capacity of the chiller, and the refrigerant type of the compressor.
2. According to the use and cooling load, the Screw Compression chiller should be selected.
3. A refrigeration system with long periods of low load operation, a Screw Compressor unit, or a multi-head piston compressor unit should only be used for saving energy and for easy adjustment.
4. While choosing Screw Compression Chiller, preference should be given to units with a higher coefficient of performance value.

According to statistics, under 100% load, the average operating time of the Chiller is about 1/4 of the total running time.

The ratios of operating time 100%, 75%, 50%, and 25% of the total operating time were approximately 2.3%, 41.5%, 46.1%, and 10.1%.

Therefore, preference should be given to models that have a flatter efficiency curve in the selection of a Screw Compressor Chiller.

Load should be considered when sketching and selecting the adjustment range of the Screw Compression Chiller at the same time.

The Screw Compression Chiller with a multi-head can be selected according to actual conditions as it has an excellent partial load performance.

5. Concentrate on the nominal working condition when selecting a Screw Compression Chiller.

The cooling capacity of a Screw Compressor Chiller depends on the following conditions;

1. Flow rate as well as the effluent temperature of the chilled water.
2. The temperature of inlet water, flow rate, and cooling water’s fouling coefficient.

6. While selecting a Screw Compression Chiller, focus on the normal working range of the unit.
7. The temperature of the cold water of the outlet should not be allowed to exceed 15°C in the selection of design under normal operating conditions.
8. In an air-cooled screw chiller, the temperature of an outdoor dry bulb should not be allowed to exceed 43 °C.

Air Cooled Screw Chiller

How to Increase the Working Efficiency of your Screw Compressor Chiller?

Treatment of condenser water:

Untreated water is the result of damage to tubes, piping, and other materials.

Maintain refrigerant charge:

The cooling capacity of a Screw Compressor Chiller depends on the amount of refrigerant moving through the compressor at a particular time.

The proper level of refrigerant should be kept in mind.

Check Wiring:

Consult the guidelines of the manufacturer for efficient starter and motor operation. Also, keep track of the safety as well as sensor calibrations on microprocessor controls.

Also, don’t forget to check the electrical connections of the chiller, wiring, and switchgear for hot spots and worn contacts.

Prevention of insulation faults is necessary by checking and protecting electrical connections.

It is important to check the shaft seal on open drive motors to prevent refrigerant leakage and clean the motor cooling air vents. This maximizes cooling.

Screw Compressor Chiller Inspection

What are the Limitations of using a Screw Compressor Chiller?

1. The maximum pressure of water of the condenser is 225 PSIG. This decreases the flexibility of the Screw Compressor Chiller.
2. The maximum allowable water pressure of the evaporator is 150 PSIG (1034 kPa).
3. The upper limit of the discharge temperature is 155°F (68°C).
4. The maximum allowable water temperature of an evaporator of a Screw Compressor Chiller when it’s turned off is 100°F.
5. The highest possible temperature for an operating cycle is 90°F/32.2-degree Celsius.
6. The allowable temperature of the water leaving from the evaporator is 40°F (4.4°C).
7. Minimum condenser water entering temperature per the chart above.

What are the Installation Guidelines for a Screw Compressor Chiller?

The perfect installation of the Screw Compressor Chiller is necessary to ensure normal operation, prolong the service life, and save energy for the Screw Compressor Chiller.

For this purpose, professionals should participate in the installation.

1. Filled the Refrigerant

Before being dispatched for delivery, the Screw Compressor Chiller is filled with refrigerant.

After the on-site installation, the relevant valve can be opened directly in case of no accidental damage.

If there is leakage of the refrigerant then you need to check the point of leakage. After doing so, you need to add an appropriate grade of the refrigerant as stated in the manual.

The charge of the refrigerant should be according to the technical requirements

2. The refrigerant charge and refrigerant grade must be under regulations. If the refrigerant charge is insufficient. This will result in not proper cooling.

An inappropriate charge (either too high or too low) increases the cost of the system as well as harms the system operating energy requirements.

3. Prepare an adequate amount of refrigerant before charging the refrigerant. The refrigerant can also be directly charged from the special filling valve.

As there is a vacuum in the system, the pressure difference between the refrigerant and the system in the cylinder is significantly large.

4. The refrigerant is immediately replaced by the cylinder when the valve is opened.

In the flow system, after closing the liquid filling valve, the connecting pipe should be removed.

Screw Compressor Chiller Installation

How to Maintain your Screw Chiller Compressor?

Like all the other cooling appliances including standard chiller, it is very important to adequately and appropriately maintain the Screw Compressor Chiller. Adequate maintenance increases the life span of the system.

Maintenance of Major Parts

A Screw Compressor Chiller has four major parts oil components, suction valve, air-end, and electric motor.

Vibration can also be a problem

There is special equipment that is used to control vibration. For a Screw Compressor Chiller, vibration is not too much high, so this cost is avoided.

All fasteners must be tightened to control vibration. Regularly check the bolt, nuts, and screws and tighten them if they are loose.

To prevent the failure of equipment, check the noise of oil leaks and also the bearings, and call an engineer if you find any problem.

Main Points

• To check water and refrigerant
• Checks oil conditions once a week.
• Inspection and cleaning of filters once a week.
• Remove the debris and dirt on the unit exterior.

How to Troubleshoot your Screw Compressor Chiller?

1. Probable Cause

The Screw Compressor Chiller anchor bolts may tighten or lose the anchor bolts.

Treatment

Monitor the anchor bolts and tighten or lose them as required.

2. Probable Cause

The actual shaft of the Screw Compressor and the Compressor’s motor shaft may not align.

Treatment

Check and align the motor’s shaft.

3. Probable Cause

The increase in the vibration of the pipelines also increases the vibration of the units.

Treatment

Change the points of support or add support points.

Extra Cooling Capacity Troubleshooting:

1. The position of the spool valve may not be suitable for other faults, check the indicator position, check the spool valve, and also the angular displacement.
2. In case of insufficient refrigerant, check the oil filter to increase the injection amount of the fuel.

Troubleshooting the clamoring sound of the Screw Compressor Chiller during the start of the operation and completion of operation:

1. The rotor and the suction need to be examined carefully in case of any waste in the rotor tooth groove.
2. If the thrust bearing is damaged or harmed in one way or the other, put back the bearing.
3. In case the main bearing is worn, the rotor needs to be rubbed against the body.

Drop-in Temperature Troubleshooting

1. If there is the inhalation of the wet flow, the amount of the liquid that is supplied to the evaporation system needs to be brought down.
2. If the exhaust pressure has fallen abnormally, it should be treated by decreasing the water supply.

Troubleshooting High Temperature of the Body of the Screw Compressor Chiller:

1. If the moving parts of the Screw Compressor are abnormally worn then the damaged parts need to be either repaired or replaced.
2. Overheating of the body can be corrected by decreasing the consumption of superheat.

Screw Compressor Chiller Troubleshooting

FAQs of a Screw Compressor Chiller

What is the Purpose of Slide Valve Adjustment in a Screw Compressor Chiller?

By using the slide valve adjustment you can easily accomplish energy stepless adjustments.

What does an Oil Pressure in a Screw Compressor Chiller do?

The oil pressure in a piston-cylinder of a Screw Compressor Chiller pushes the piston and spool to be in backward/forward motion in the compression chamber.

What to Do if there is Insufficient Oil Return in the System of Screw Compressor Chiller?

It is suggested to install another oil separator between the compressor venting condensers to lessen the oil entering the system.

What Type of Evaporator a Screw Compressor Chiller Use?

You can use three types of evaporators for a Screw Compressor Chiller, mentioned below.

• Dry shell and tube evaporator.
• Flooded evaporator.
• Falling film evaporator.
• What is meant by the Chilled Water Flow Rate in a Screw Compressor Chiller?

The chilled water flow rate depends on the material, density, and heat transfer ratio of the application to be cooled. It can be calculated by using simple formulas.

What is the Cooling Medium in a Screw Compressor Chiller?

The cooling medium may include tap water, ethylene glycol solution, seawater, etc.

What Type of Mechanical failures you can Face While Using a Screw Compressor Chiller?

Some mechanical failures are given below.

• Compressor oil filter failure.
• Oil stop valve failure.
• Abnormal oil regulator.
• Air filter failure.

What is the Cause of Abnormal Vibrations of a Screw Compressor Chiller?

Untightened anchor bolts, misaligned motor shaft, and high vacuum in the suction chamber can cause abnormal vibrations.

What is the Cause of Extremely High Temperature of the Body of a Screw Compressor Chiller?

Moving parts are not worn properly, inspiratory swear overheating, bypass line leakage and the very large compression ratio can cause high body temperature.

100% Quality Tested Screw Compressor Chiller