Both air-cooled screw chillers and water-cooled screw chillers use semi-hermetic screw compressors, and screw compressors have a high energy efficiency ratio. At present, the compressors of screw-type industrial chillers mostly use compressor brands such as Hanbell Bitzer, Fusheng, and Refcomp and other compressor brands. The main difference between the air-cooled screw chiller and the water-cooled screw chiller is the form of heat dissipation. The air-cooled screw chiller uses a fan to dissipate heat, uses air as the cooling medium, and dissipates heat through the air through a fin condenser and a low-noise fan. To cool the refrigerant, the water-cooled chiller uses water as the cooling medium, and then the cooling water cools the refrigerant.

Secondly, the installation of the air-cooled screw chiller is simple and does not require a cooling tower. Because the screw chiller machine is relatively large, an external water tank is used. The air-cooled screw chiller is greatly affected by the ambient temperature, especially in some areas with high ambient temperature, which will cause poor cooling effect and may cause a high-pressure alarm due to excessive temperature. As the air-cooled screw chiller’s water quality requirements are small, so we recommend installing an air-cooled screw chiller where the water quality is not good. The water-cooled screw chiller is not affected by the environment, and the cooling effect is better than the air-cooled screw chiller. In the case of the same cooling capacity, due to the lower condensing temperature of the water-cooled screw chiller, higher cooling effect, lower power and lower power consumption, the operating cost of the water-cooled screw chiller is lower than that of the air-cooled screw chiller machine.

Therefore, when purchasing a screw chiller, whether to choose an air-cooled screw chiller or a water-cooled screw chiller requires us to consider the environment, installation, and cost. If you are still hesitating about how to choose a chiller, contact us and a professional refrigeration engineer will give you advice. Email: oumal@oumal.com.

In the process of using the chiller, have you encountered the problem that the chilled water of the chiller does not circulate? How to solve the problem of the chilled water not circulating?

We all know that under normal circumstances, small industrial chillers have been equipped with chilled water circulation pumps, such as Packaged air-cooled chillers, box-type water-cooled chillers, and large capacity chillers such as screw chillers and open-type water chillers. The chiller does not contain a chilled water circulating pump. At this time, when installing the cooling water system, an external chilled water circulation pump must be installed, so that the cooling water returns to the chiller for cooling after absorbing the heat of the cooling equipment, so that the cooling water supply pipe forms a circulation system.

It should be noted that no matter whether the chilled water pump is inside the built-in chiller case or outside the chiller, it is recommended that the location of the chilled water pump should be lower than the water level of the water tank. In this way, the circulating water pump can absorb cooling water well. However, in some cases, due to the needs or limitations of the installation environment, the chilled water pump may be higher than the water level of the water tank, so that the cooling water system cannot absorb water during operation, resulting in the chiller. In the case of insufficient chilled water flow, it cannot be started and a fault is reported. So what should we do when the chiller fault code shows insufficient chilled water flow?

1. Use a rubber tube (open its small valve) to send back the water supply pipe reserved on the large pipe on the water tank, and use a wrench to unscrew the vent plug of the cold water circulation pump (if there is water before tightening), until the water is removed. Return to the large tube in the tank and pull the hose out to see if any air bubbles come out. If it does, keep pouring water into the tank until the return water returns to the large pipe in the tank, then unplug the hose and see if any air bubbles come out. If yes, keep pouring water. Close the small valve until there are no air bubbles.

2. At this point, turn on the chiller for 1 minute. If the big pipe has a lot of water back into the pool, that's fine.

3. If the return water is not enough or there is no return water, repeat the above irrigation operation.

When you purchase and install the Oumal industrial chiller, if the chilled water flow is insufficient during the installation test, please contact our sales in time, we will arrange a professional engineer to guide you to solve the problem. Tel: +86 15112554736.

Sand mill, also known as laboratory bead mill, or nano sand mill, is mainly used for wet grinding of chemical liquid products. It is mainly composed of body, grinding cylinder, sand grinding disc (lever), grinding medium, motor and feeding pump. The speed of feeding is controlled by the feeding pump. The grinding media of this equipment are generally divided into zirconia beads, glass beads, zirconium silicate beads, etc.

 

Since the sand mill (bead mill) is working, the material and the grinding medium will have strong collision and friction, which will generate a lot of heat energy, and the grinding inside of the sand mill should generally not exceed 65 degrees. The machine protection temperature will cause the temperature switch to act, and the sand mill will automatically stop for protection, thus affecting the production efficiency. Inversely, if the internal temperature of the grinding is too low, the viscosity of the grinding slurry will be too high, the action motor cannot be driven, and the grinding motor may be burned. It can be seen that the sand mill must match the cooling system.

The functions of the Oumal sand mill chiller system in the sand grinding process are as follows:

 

1. Effective control of slurry dehydration. Most of the energy consumed by grinding is converted into heat energy, which increases the temperature of the air and material. For ball mills, the high temperature inside the grinding chamber will lead to dehydration of the slurry, which will adversely affect the setting time and strength of the slurry. Oumal sand grinding cooling system can avoid this phenomenon.

 

2. During the sanding process, the surface of the slurry absorbs a part of the air to form an air film, which hinders the electrostatic interaction between the particles and avoids the adsorption and condensation on the surface of the particles. However, when the temperature exceeds 100 °C, the air film adsorbed on the surface of the particles is destroyed, and adsorption and coalescence are formed between the particles and the particles, and between the particles and the lining plate of the grinding body under the electrostatic action, which plays a buffering role in the grinding. Reduced grinding efficiency. This effect increases with the increase of the specific surface area of the product and the increase of the temperature in the mill. Therefore, water cooling system can improve the grinding efficiency.

 

3. When grinding cement, the material entering the grinding temperature is generally higher than the material entering the grinding temperature when grinding raw meal, and the product fineness is also relatively fine. Therefore, the temperature inside the mill is higher. If it is not cooled, the temperature of the cylinder body is too high, on the one hand, the gap between the lining plates will become smaller due to thermal expansion. In severe cases, the lining plate will be squeezed together to bulge and the lining plate screws will be broken. On the other hand, the temperature of the cylinder body will also be conducted. To the hollow shaft, the temperature of the hollow shaft is too high and equipment accidents are caused. Therefore, water chiller systems will improve the safe operation of the equipment.

 

Oumal Chiller specializes in the production and processing of various specifications and models of industrial chillers, which can be used for cooling and cooling of grinding equipment such as sand mills, bead mills, and grinders. downtime. The chiller is compact in structure, easy to move, high efficiency, low noise, power saving and durable. It can effectively control the temperature of the sand mill to ensure that the material temperature and material do not deteriorate. It is a kind of matching refrigeration equipment that can prevent high temperature during the operation of the sand mill equipment and keep the equipment within a certain cooling temperature range through continuous water circulation. normal operation of the sand mill.

Spot welding machine is a kind of mechanical equipment. It adopts the principle of double-sided double-point overcurrent welding. When working, two electrodes pressurize the workpiece so that the two layers of metal form a certain contact resistance under the pressure of the two electrodes, and the welding current changes from one When the electrode flows through the other electrode, the two contact resistance points form an instant thermal fusion, and the welding current flows from the other electrode to the electrode along the two workpieces to form a loop instantly, and will not damage the internal structure of the welded workpiece. Because the resistance welding machine is in the working process, the resistance head is prone to high temperature, which affects the accuracy of the processed product, so a chiller is needed to cool it next to ensure the accuracy of the processed product. The spot welding machine is equipped with a chiller, which can improve the safety and stability of the welding work and extend the life of the welding machine.

Industrial chillers used for spot welding operate like recirculating coolers as they use the same closed-loop setups. However, process chillers can be modified to handle industrial cooling on a larger scale. Industrial chillers also have condensers, evaporators, and automated temperature controls that make them more efficient. Air cooled chiller is a good choice for spot welding machine, It’s easy to installation and move.

A general rule for sizing a chiller is that, for every 100KVA of welder, you should have about a 1-ton chiller. For example, if you want to cool 4 welders that are 100KVA each, you will need a 4-ton chiller. If you want to cool a 300KVA machine, you will need a 3-ton chiller. See below for further sizing details.

To calculate for resistance welding:

BTU/hr = (welder KVA) x (duty cycle) x (0.85) x (0.6) x 3415 BTU/hr

To calculate for resistance welding:

BTU/hr = (welder KVA) x (duty cycle) x (Eff power supply) x (Eff heat collection) x 3415

Eff. power supply = the percentage of output to input power

Eff. heat collection = the percentage of heat absorbed by chilling water (varies by approximately 50-70%)

Duty cycle = weld time on/ time elapsed

As a leading industrial chiller manufacturer, OUMAL CHILLER is dedicated to supplying high-quality process chillers for a wide range of industries. Our knowledgeable staff will help you find the industrial chiller best suited to your unique process application. Contact us to choose the spot welding cooling system for your spot welding machines. The air cooled chiller is your good choice for Industrial welding chillers.

We all know that according to different heat dissipation methods, chillers can be divided into air-cooled chillers and water-cooled chillers. What is the difference between air-cooled chillers and water-cooled chillers?

1. The air-cooled chiller uses copper tubes and aluminum fins to dissipate heat from the condenser. A fan is required to blow the outdoor air through the heat exchange fins and take away the heat of the condenser, so the air-cooled chiller does not need to be connected to the cooling tower. But compared with water-cooled chillers, under the same power, air-cooled chillers have larger equipment size and higher noise. The condenser of water-cooled chillers exchanges heat with the cooling water from the cooling tower through the heat exchanger. The excess waste heat will be transported to the cooling tower through the cooling water loop and released into the atmosphere, or enter the water-water heat exchanger or soil heat exchange coil for storage. Therefore, water-cooled chillers do not need fans to dissipate heat, but need cooling towers or water (ground) source heat exchange pipelines. Water-cooled chillers have one more cooling water system than air-cooled chillers. The size of the unit of the same power is smaller than that of the air-cooled chiller, it does not take up space, and the noise is lower, but it needs a cooling tower and the equipment needs a computer room.

2. In terms of refrigeration and heat exchange switching, the air-cooled chiller-type refrigerant loop switches the flow direction through a four-way valve to exchange the condenser and the evaporator. In summer, heat is transferred from indoor to outdoor, and in winter, it absorbs heat from outdoor. indoor. The water-cooled chiller does not have the ability of evaporator and condenser interchangeability, so the unit connected to the cooling tower does not have the heating function (requires an external boiler). The heat pump unit needs to switch the chilled water and cooling water loops, and 8 water circuit switching valves are added in the machine room. In summer, cold water enters the house, hot water enters the external coil, and winter hot water enters the house, and cold water enters the external coil. (Some small water source heat pump units also have refrigerant four-way valves)

3. In the case of the same cooling capacity, the model of water-cooled chiller is smaller, because the energy efficiency ratio of water-cooled chiller is higher than that of air-cooled chiller, and the compressor of air-cooled chiller is better than water-cooled chiller. Great horsepower.

4. In terms of installation, the air-cooled chiller is easy to install, while the installation pipeline of the water-cooled chiller is more complicated.

 

If you don’t know whether to choose an air-cooled chiller or a water-cooled chiller when choosing a chiller, you can contact us. We will recommend to you a suitable chiller based on your on-site installation, the budget of the chiller, and the size of the model. Email: oumal@oumal.com

 

The high-pressure failure of the chiller means that the compressor discharge pressure is too high, which causes the high-pressure protection relay to operate. The compressor discharge pressure reflects the condensing pressure, the normal value should be 1.4~1.8MPa, and the protection value setting is recommended not to exceed 2.0MPa. Because the long-term pressure is too high, it will cause the compressor to run too much current, easily burn the motor, and cause damage to the compressor. So what is the main cause of high pressure failure? How to solve it?

1. Excessive refrigerant charge. This situation generally occurs after maintenance, and it is manifested as high suction and discharge pressure and balance pressure, and the compressor operating current is also high.

Solution: The refrigerant should be discharged according to the suction and discharge pressure and the balance pressure and the operating current under the rated conditions until it is normal.

2. The cooling water temperature is too high and the condensing effect is poor. The rated working conditions of the cooling water required by the chiller are between 30 and 35. High water temperature and poor heat dissipation will inevitably lead to high condensing pressure. This phenomenon often occurs in high temperature seasons.

Solution: The reason for the high water temperature may be the failure of the cooling tower, such as the fan is not turned on or even reversed, the water distributor does not turn, it is manifested as the cooling water temperature is very high, and it rises rapidly; the outside temperature is high, the water path is short, and it can be circulated In this case, the cooling water temperature is generally maintained at a relatively high level, which can be solved by increasing the storage tank.

3. The cooling water flow is insufficient, and the rated water flow cannot be reached. The main performance is that the pressure difference between the inlet and outlet water of the unit becomes smaller (compared with the pressure difference at the beginning of the system's operation), and the temperature difference becomes larger.

Solution: The pipeline filter is clogged or the selection is too fine, and the water permeability is limited. Choose a suitable filter and clean the filter regularly; or the water pump is small and does not match the system.

4. The condenser is fouled or blocked. Condensate water generally uses tap water, it is easy to scale when it is above 30, and because the cooling tower is open, it is directly exposed to the air, dust and foreign matter can easily enter the cooling water system, causing the condenser to be dirty and blocking, and the heat exchange area is small. The efficiency is low, and it also affects the water flow. The performance is that the pressure difference and temperature difference between the inlet and outlet water of the unit become larger, the upper and lower temperatures of the condenser are very high when the condenser is touched by hand, and the condenser outlet copper pipe is hot.

Solution: The unit should be backwashed regularly, and chemical cleaning and descaling should be carried out if necessary.

5. False alarms caused by electrical faults. Because the high-voltage protection relay is damp, poorly contacted or damaged, the unit electronic board is damp or damaged, and the communication failure causes a false alarm.

Solution: For this kind of false fault, the HP fault indicator on the electronic board is often off or slightly bright, and the manual reset of the high-pressure protection relay is invalid. The running current of the compressor is normal, and the suction and exhaust pressures are also normal.

6. The refrigerant is mixed with non-condensable gases such as air and nitrogen. There is air in the refrigeration system. In many cases, the pointer of the high-pressure meter will vibrate severely when there is a lot of air.

Solution: This situation generally occurs after maintenance, and the vacuum is not complete. It can be evacuated at the highest point of the condenser after shutdown or re-evacuated to add refrigerant.

If your water chiller machine has a high-pressure alarm, you can check according to the article. Or you can contact the water chiller factory to help you solve it. Need to know the details of our water chiller machine, please visit the products page.

What is Blow Molding Machine?

Blow molding machine is a kind of equipment that makes plastic particles into hollow containers through a blow molding process. At present, the more common models include: a hollow extrusion blow molding machine that uses PP and PE for one-time molding, and uses PET, PC or PP for two moldings. The injection-stretch-blowing blow molding machine and the newly developed multi-layer hollow extrusion blow and stretch blow molding. At present, most of the blow molding machines are also two-step blow molding machines, that is, the plastic needs to be made into preforms and then blown. Nowadays, environmentally friendly plastics made of PET are commonly used.

Production process of Blow molding machine

The working process of the bottle blowing machine is generally to place the preform in the preform container, automatically enter the preform positioning device through the conveying device, and then load the preform mouth upwards onto the preform holder, and then send it to the drying tunnel for heating After that, the preform is sent to the blowing platform, and then the mold is locked, followed by low-pressure blowing and high-pressure blowing. After cooling and forming, the high-pressure gas in the bottle is discharged, and finally the mold is opened. The finished bottle is taken from the blowing platform by the automatic demoulding system Come down. In the cooling molding process, the chilled water provided by the chiller is used to cool the bottle wall and prevent the mold from overheating and damage.

What is a blow molding chiller ?

Blow molding chiller is the cooling system which provide cooling water for the blow molding machine. Because the bottle blowing machine generates a lot of heat during the production process, and the ambient temperature is getting higher and higher, tap water or cooling towers can no longer cool the bottle blowing machine, resulting in a decline in product refrigeration. Therefore, the bottle blowing machine chiller Used, it can effectively improve the surface finish of plastic products, reduce the surface marks and internal stress of plastic products, make the products do not shrink or deform, reduce defective products, is suitable for demoulding of plastic products, accelerate product shaping, and shorten the injection molding cycle. Greatly improve the production efficiency of the bottle blowing machine.

How to choose a suitable chiller for the bottle blowing machine.

First determine the control temperature and cooling capacity required by yourself, such as how much water you need per minute to finalize. Generally, the water chiller is selected according to the requirements for cooling water provided by the blowing machine manufacturer. Generally, the temperature of the outlet water is 10℃, and the cooling water flow requirements of different models. Some manufacturers will directly mark the horsepower of the chiller in the parameters.

If you are looking for the industrial chiller for your bottle blow machine, You are welcomed to contact us to get the blow molding chiller price.

In many special use environments, companies need to apply water-cooled chillers. Since water-cooled chillers need the help of cooling towers during operation, they need to follow the instructions introduced by the chiller manufacturer after purchasing water-cooled chillers. Relevant experience, complete the normal operation of water-cooled chillers, and ensure high performance of water-cooled chillers.

 

How to choose to buy a cooling tower?

In the actual use environment, there are different types of cooling water towers. Simply distinguished from the shape, domestic cooling water towers are divided into two types: rectangular and circular. As for the specific functions, rectangular and circular cooling towers have similar functions, and there is no According to the introduction of the refrigerating machine factory manufacturer, the circular cooling tower can adapt to more use environments and achieve the purpose of improving the working efficiency of water-cooled chillers.

 

Determine the model and specific specifications of the cooling tower

 

Different water-cooled chillers need to be matched with different specifications of cooling towers. In the selection process, it is necessary to select suitable cooling tower equipment according to the specific data of the cooling water flow, and at the same time ensure that the water flow is in a more suitable state to ensure water cooling. According to the requirements of the refrigeration plant, the water flow rate of the cooling tower should not be higher than 20%. As long as it meets the specific value range, it can meet the needs of water-cooled chillers.

 

Specifications of cooling tower

 

In the process of purchasing a cooling tower, as to which specifications to choose, you need to complete the entire selection process according to actual needs, such as the specific operating power of the water-cooled chiller, and the amount of water inflow and discharge, combined with specific data to select the appropriate cooling tower product. At the same time, it should be noted that normal water-cooled chillers need to be equipped with a cooling water tower. The number of cooling water towers to be purchased needs to be determined according to the actual number of water-cooled chillers, and the principle of one-to-one purchase is realized, so as to meet the normal conditions of water-cooled chillers. Operational requirements.

 

For the introduction of cooling water tower selection techniques, users can realize that water-cooled chillers can meet daily production needs only when they cooperate with cooling water towers. The lack of any equipment has a great impact on cooling water towers. Therefore, choosing high-quality cooling water towers will improve The specific performance of water-cooled chillers plays a vital role.

Generally, when we choose a cooling tower, there is a commonly used formula:

Cooling water flow = host refrigeration capacity (KW) * 1.2 * 1.25 * 861/5000 (m3/h)

Cooling water volume = host condenser load (kcal/h) * 1.2/5000 (m3/h)

Cooling water volume = host condenser heat load (m3/h) * 1.2 (m3/h)

Cooling water volume = host cooling capacity (RT) * 0.8 (m3/h)

Cooling water volume = heat load of main engine evaporator (kcal/h) * 1.5 * 1.25/5000 (m3/h)

Cooling water volume = heat load of main engine evaporator (m3/h) * 1.2 * 1.25 (m3/h)

Cooling water volume = host evaporator heat load (RT) * 1.2 * 1.25 * 3024/5000 (m3/h)

Note: 1.2 above is the selection margin, 1.25 is the condenser load factor

 

Oumal Refrigeration has a professional technical team. We will select suitable cooling towers for customers' water-cooled chillers. If customers purchase by themselves, we will also recommend suitable cooling tower models to customers. If you need to know the price of the cooling tower, please contact our sales staff.

In a chiller cooling water system, the water pump is an indispensable component. The water pump can be installed in the chiller or outside the chiller. Generally, we install the water pump in the chiller unit for air-cooled chillers. , So that the chiller is easy to install. For a water-cooled chiller, a system requires at least two water pumps. One pump is installed in the chiller to provide chilled water for the chilled water pump and equipment that needs to be cooled, and the other is installed outside the chiller and connected to the cooling water tower to provide the condenser. Cooling water. Screw-type chillers generally do not install the water pump inside the chiller, but directly install it outside together with the external water tank. The role of the water pump is so important in the chiller, how do we choose the right water pump?

The water pump of the chiller generally adopts centrifugal type, so when choosing a water pump for the chiller, you must first determine the flow and head of the pump.

Determination of pump flow:

We can calculate the energy balance of the chiller as a system. The heat entering the system includes: the cooling capacity plus the motor power, the heat removed from the system, the heat carried by the cooling water and the heat dissipated in the environment, and the heat transferred to the environment is omitted. According to the process requirements (inlet water temperature and outlet water temperature), the flow of circulating water can be obtained. For example, the total maximum cooling capacity of a centrifugal chiller and a screw chiller is 2637+1231=3947KW, The motor power is: 467+256=723KW, and the total heat (cold) generated by 4670KW needs to be removed. If the cooling water passes through the cooling tower to change from 37°C to 32°C according to the design requirements, the amount of heat it brings out is The water volume should be: 4670÷1.163×1000÷(37-32)=803.1m3/h, (1.163 is the conversion coefficient between kilowatts and KCal). The flow rate of the pump that should be determined in this way can generally be considered for two pumps to operate, and one for standby. In order to facilitate the operation in the high temperature period.

The second is the pump head. It should calculate the resistance loss based on the flow rate of the water in the pipeline (determined by the size of the pipeline), the length of the pipeline, the local resistance (the condenser in the chiller (can be found in the manual), and the control parts. Cooling water is a circulating system, you don’t need to consider the height difference, just add the height difference of the cooling tower. The pipe flow rate is generally about 1m/s, you can press: (pressure drop per meter of pipe MPa/m) i= The formula is 0.0000107×V×V÷d^1.3, where V is the average flow velocity (m/s), so the pump head is also determined.

Omar’s professional industrial chillers have been produced for many years. We have professional engineers who will select professional chillers and appropriate pumps for you, customize your cooling water system according to your needs, and improve your production efficiency and products. quality.

The application of chillers is very wide, including plastic industry, chemical industry, packaging industry, printing industry, food industry, etc. Today we will talk about how to choose chillers in the food industry. The water chiller used in the food industry needs to be used for rapid cooling of all kinds of food after heating, so that it can be suitable for canning and bottling requirements. In addition, various fermented foods require different cooling temperatures to stabilize fermentation needs and improve fermented products. To ensure the quality of fermentation, it is also used in the pharmaceutical, chemical industry, and refrigeration equipment.

When choosing a chiller in the food industry, first consider the temperature of the chilled water required in the process, whether to use a medium-temperature chiller or a low-temperature chiller, and secondly, consider whether the cooling water needs to be in direct contact with the food? If it is to directly cool food, the place where the material of the chiller contacts water must be stainless steel or PVC. If it is to cool food indirectly, use an ordinary industrial chiller. In addition, add a detachable plate heat exchanger. If the temperature is lower than 5 degrees, the chiller is a low-temperature chiller, and ethylene glycol needs to be added to the cooling water. The chiller must indirectly cool the food. Another factor to consider in the chiller industry is the shell sheet metal of the chiller. Customers will require stainless steel sheet metal to make the chiller's chassis for easy cleaning. Therefore, when we select food chillers for customers, we must first understand the process flow, temperature and material requirements. The price of stainless steel chillers is slightly higher than that of ordinary chillers. So you can choose the appropriate chiller according to your needs and budget.

If you need a food processing chiller cooling system, please contact us. OUMAL Refrigeration has a professional technical team to customize your own industry chiller for your cooling water system. The price of OUMAL chiller is favorable, welcome to inquire.