What is a Split-Case Pump?
A split-case pump is a type of centrifugal pump that has two separate casing halves, that are bolted together. This design allows for easy access to the internal parts and maintenance without disassembling the entire pump. The impeller is located in the center and rotates inside the casing, which creates a fluid flow by centrifugal force. Split-case pumps are commonly used in commercial and industrial applications, such as HVAC systems, municipal water systems, and oil refineries. They are designed to handle high-flow volumes at low to medium head pressures.
A Split-Case centrifugal pump is a type of machine used to pump liquid at a variety of rates. The device consists of two halves, which are separated by the diameter of the shaft running through the center. This allows for efficient pumping and reduces wear and tear on the machine’s moving parts. Split-Case Pumps can be configured to provide variable speeds or constant speed, depending on the application’s needs.
Types of Split-Case Pumps
There are several types of split-case pumps:
1. Single-stage, horizontally split-case pump: This is the most common type of split-case pump. It has a single impeller and a horizontally split casing.
2. Multistage, horizontally split-case pump: This type of split-case pump has multiple impellers in series and a horizontally split casing.
3. Vertical split-case pump: A vertical split-case pump has a vertically split casing and can be single or multi-stage.
4. Axially split-case pump: An axially split-case pump has a casing that is split axially (along the shaft axis) and can be single or multi-stage.
Advantages and Disadvantages.
Advantages of split-case pumps:
2. Easy maintenance: The split-case centrifugal pump design of these pumps allows for easy access to the impeller and other internal components, making maintenance easier and less time-consuming.
3. Reduced noise and vibration: Since the impeller is mounted on a shaft that is supported by bearings on both ends, split-case pumps generate less noise and vibration than other types of pumps, reducing unwanted noise pollution.
4. Versatility: Split-case centrifugal pump can be used for a wide range of applications, including water supply systems, HVAC systems, industrial processes, and firefighting.
Disadvantages of split-case pumps:
1. Size and weight: Split-case pumps tend to be larger and heavier than other pump types, making installation and transport more difficult and costly.
2. Limited pressure capacity: Despite their high flow rate capabilities, split-case pumps have limited pressure capacity compared to other pump types, making them unsuitable for high-pressure applications.
3. Higher initial cost: These pumps are more expensive than other types of pumps due to their complex construction, which may not be cost-effective for some smaller projects.
4. Water leakage: Split-case pumps are susceptible to water leakage around their seal areas, which can result in increased maintenance costs over time.
Common Applications of Split-Case Pumps
Split-Case pumps are mainly used in the industrial sphere, particularly for applications involving higher pressures or longer operating times.
1. HVAC Systems: Split-case pumps are commonly used in heating, ventilation, and air conditioning systems for circulating water and other fluids.
2. Municipal Water Treatment Plants: These pumps are often used in municipal water treatment plants for distributing drinking water, fire protection, irrigation and water circulation.
3. Industrial Manufacturing: Split-case pumps are also used in industrial manufacturing applications such as chemical processing, mining, power generation, and paper mills.
4. Agriculture: These pumps are extensively used in the agricultural sector for irrigation and water distribution, ensuring proper crop growth and yield.
5. Oil and Gas Industry: Split-case pumps are widely used in the oil and gas industry to circulate and transport fluids such as crude oil, natural gas, and refined petroleum products.
6. Wastewater Treatment: In wastewater treatment plants, these pumps move sludge and other wastewater materials from one treatment unit to another.
7. Mining: In mining applications, split-case pumps are used for dewatering operations, transporting slurries, and pumping water from mining pits.
8. Fire Protection: Split-case pumps are used in fire protection systems to provide reliable and continuous water supply for firefighting.
Base Materials Used for Split-Case Pumps.
Top manufacturers of split-case pumps include Grundfos, Flowserve, Sulzer, KSB, and Ebara.
Base materials used for split-case pumps include:
1. Cast iron: This material is commonly used for split-case pump casings as it is durable, cost-effective, and can withstand high pressures.
2. Bronze: Bronze is often used for the impellers of split-case pumps as it has good corrosion resistance and is well suited for handling seawater, acidic liquids, and other corrosive fluids.
3. Stainless steel: Stainless steel is frequently used for the shaft and other components of split-case pumps that are exposed to corrosive or abrasive fluids as it is highly resistant to both corrosion and wear.
4. Carbon steel: Carbon steel is used for certain parts of split-case pumps, such as the frame, as it is strong and robust, making it an excellent choice for heavy-duty applications.
5. High-temperature alloys: In some cases, split-case pumps may need to handle high-temperature liquids, in which case high-temperature alloys such as Inconel or Hastelloy may be used for their superior heat resistance.
Split case horizontal pump
A split case horizontal pump is a type of centrifugal pump where the casing is split into two halves along the horizontal plane. This allows for easy access to the internal components of the pump, such as impellers and shafts, without the need to dismantle the entire unit.
The split case centrifugal pump design also typically results in a more balanced hydraulic design, which improves pump efficiency and reduces wear on the components. These pumps are commonly used in industrial and municipal applications, such as water supply and irrigation, HVAC systems, and chemical processing.
Split case horizontal pumps can handle a wide range of flow rates and pressures, and are known for their reliability and long service life. They are available in various materials, including cast iron, bronze, and stainless steel, to suit different applications and fluid types.
Horizontal split case pump parts
1. Pump casing – houses the impeller and other components
2. Impeller – rotates and creates a flow of fluid
3. Shaft – transmits power from the motor to the impeller
4. Bearings – support and guide the rotating shaft
5. Mechanical seal – prevents leakage between the pump casing and the shaft
6. Seal housing – houses the mechanical seal
7. Stuffing box gland – seals the shaft where it exits the pump casing
8. Motor frame – supports the electric motor
9. Coupling – connects the pump shaft to the motor shaft
10. Baseplate – supports the pump and motor
11. Suction nozzle – connects to the piping system and draws in fluid
12. Discharge nozzle – connects to the piping system and expels fluid
13. Bolts – secure the pump casing to the baseplate
14. Gaskets – provide a seal between pump components
15. Wear rings – reduce metal-to-metal contact and prevent damage to the impeller and casing
16. Spacer coupling – allows for easy maintenance and replacement of mechanical seals
17. Relief valve – protects the pump from over-pressurization
18. Pressure gauge – measures the pressure at the pump discharge
19. Flow meter – measures the flow rate of the fluid
20. Drain plug – allows for draining of the pump and piping system during maintenance.
Uses:
Agriculture, Irrigation, Water supply systems, HVAC, Fire protection, Industrial processes, Power generation, Oil and Gas, Mining, Chemical processing, and many others.
Split case centrifugal pump
The impeller of a split-case centrifugal pump is mounted on a shaft that is supported by bearings located outside the pump casing. When the pump is in operation, the impeller spins and creates a centrifugal force that moves the fluid through the pump’s volute or casing.
Split-case centrifugal pumps are commonly used in applications where high flow rates and high pressures are required, such as in water supply and distribution systems, irrigation systems, and industrial applications. They are generally more efficient than end-suction centrifugal pumps and can handle larger volumes of fluid.
Casing in centrifugal pump
The casing in a centrifugal pump is the outer shell that encloses the impeller and other internal components of the pump. Its main function is to convert the kinetic energy generated by the impeller into pressure energy, which is then used to move fluid through the system.
The casing of a centrifugal pump is typically made of metal, such as cast iron or stainless steel, and can be of different shapes and sizes depending on the specific application. It usually has an inlet and an outlet port that allow fluid to enter and exit the pump.
There are several types of casings used in centrifugal pumps, including volute casings, vortex casings, and diffuser casings. Volute casings are the most common and consist of a spiral-shaped chamber that gradually increases in size as it extends away from the impeller. This design helps to convert the kinetic energy of the fluid into pressure energy and reduces the amount of turbulence in the fluid flow.
Vortex casings are used in pumps that handle fluids with high levels of solids or entrained gases. They have a unique design that creates a swirling motion in the fluid, which helps to separate solids and gas from the fluid flow.
Diffuser casings are used in high-pressure applications and consist of a series of vanes that help to convert the kinetic energy of the fluid into pressure energy. They are typically used in multi-stage pumps, where several impellers and diffusers are arranged in a series to increase the pump’s overall pressure.
The type of casing used in a centrifugal pump depends on the specific requirements of the application, such as the flow rate, pressure, and type of fluid being pumped.
horizontal end suction vs horizontal split case pump
Horizontal end-suction and horizontal split-case pumps are two common types of centrifugal pumps that are widely used in industrial and commercial applications. Here are some of the main differences between the two types:
- Design: As the name suggests, the casing of a horizontal end-suction pump is designed with a single suction inlet on one end and a single discharge outlet on the other end. On the other hand, the casing of a horizontal split-case pump is divided along a horizontal plane, with the suction and discharge ports located on either side of the casing.
- Size and Capacity: Horizontal split-case pumps are generally larger and can handle higher flow rates and pressures than horizontal end-suction pumps. This is because the split-case design allows for a larger impeller and volute, which can generate more force to move the fluid.
- Maintenance: Horizontal split-case pumps are easier to maintain than horizontal end-suction pumps, as the casing can be opened without having to disconnect the piping or disassemble the entire pump. This allows for easier access to the internal components, such as the impeller, bearings, and shaft, for inspection, repair, or replacement.
- Efficiency: Horizontal end-suction pumps are generally more efficient than horizontal split-case pumps at lower flow rates and pressures. However, as the flow rate and pressure increases, the efficiency of a horizontal split-case pump may be higher due to its larger impeller and volute.
- Cost: Horizontal end-suction pumps are generally less expensive than horizontal split-case pumps, as they are smaller and have a simpler design. However, the cost difference may vary depending on the specific application requirements.
In summary, the choice between a horizontal end-suction and horizontal split-case pump depends on the specific requirements of the application, such as the flow rate, pressure, fluid type, and maintenance considerations.
Split case pump design | calculation and selection
The design, calculation, and selection of a split-case pump depends on several factors, including the application requirements, such as the flow rate, head, and fluid properties, as well as the pump efficiency, reliability, and cost. Here are some general steps to follow when selecting a split-case pump:
- Determine the required flow rate and head: This is the first step in selecting a pump, as it determines the pump size and power requirements. The flow rate is typically measured in liters per second (L/s) or gallons per minute (GPM), while the head is measured in meters or feet.
- Calculate the system resistance: This includes the frictional losses in the pipes, valves, and fittings, as well as any other pressure drops in the system. The system resistance is typically expressed in terms of a pressure loss or head loss, which is subtracted from the total head to determine the pump head.
- Select the pump impeller size and speed: The impeller is the rotating component of the pump that generates the fluid flow and pressure. The impeller size and speed are determined based on the required flow rate and head, as well as the pump efficiency and reliability.
- Calculate the pump power and motor size: Once the impeller size and speed are determined, the pump power and motor size can be calculated based on the pump efficiency and specific speed.
- Select the pump and motor: Based on the calculated pump size, power, and motor size, a suitable pump and motor can be selected from the manufacturer’s catalog.
Example: Suppose you need to select a split-case pump for a water supply system that requires a flow rate of 2000 L/s and a head of 50 meters. The system resistance is calculated to be 5 meters, and the pump efficiency is assumed to be 80%.
Using the above steps, the impeller size and speed can be calculated based on the required flow rate and head, and the pump power and motor size can be determined based on the pump efficiency and specific speed. Based on these calculations, a suitable pump and motor can be selected from the manufacturer’s catalog that meets the required specifications.
It’s important to note that the selection of a split-case pump should be done in consultation with a qualified pump engineer or manufacturer to ensure that the pump is properly sized and selected for the specific application requirements.
Split case pump calculation with example
Split-case pumps are used in a wide variety of applications, from water supply and irrigation to chemical processing and HVAC systems. Here’s an example of how to calculate the performance of a split-case pump:
Example: Suppose you need to select a split-case pump for a water supply system that requires a flow rate of 1000 liters per second (L/s) and a head of 50 meters (m). The specific gravity of water is assumed to be 1.0, and the pump efficiency is assumed to be 80%.
Step 1: Determine the pump head The pump head is the total dynamic head required by the system, which includes the frictional losses in the pipes, fittings, and valves, as well as any other pressure losses. For this example, assume the system head loss is 5 m. Therefore, the pump head is:
Pump head = System head + Static head Pump head = 50 m + 5 m = 55 m
Step 2: Calculate the required pump power The pump power is calculated based on the pump head and flow rate, using the following equation:
Pump power (kW) = (Q x H x SG) / (3.6 x η) where: Q = flow rate (m3/s) H = pump head (m) SG = specific gravity of fluid η = pump efficiency
Converting the flow rate from L/s to m3/s gives: Q = 1000 L/s ÷ 1000 = 1 m3/s
Substituting the values into the equation gives: Pump power = (1 x 55 x 1) / (3.6 x 0.8) Pump power = 21.53 kW
Step 3: Determine the pump size The pump size is determined based on the flow rate and pump head, and the manufacturer’s performance curve. Split-case pumps are typically selected based on the impeller diameter, which affects the pump’s flow rate and head. For this example, assume a pump with an impeller diameter of 400 mm is selected. Using the manufacturer’s performance curve, the pump’s flow rate and head can be determined:
Flow rate (Q) = 1050 L/s Head (H) = 58 m
The selected pump satisfies the required flow rate and head, and has a pump efficiency of 80%.
In conclusion, the example above demonstrates the basic calculation steps for selecting a split-case pump for a water supply system. However, it’s important to note that the actual selection process may involve more complex calculations, and should be performed by a qualified pump engineer or manufacturer to ensure the pump is properly sized and selected for the specific application requirements.
Rout causes and Troubleshooting of split casing pump
Here are the top 10 root causes and troubleshooting methods for split casing pumps:
- Low flow rate or no flow: This can be caused by a clogged impeller or suction strainer, a closed or partially closed discharge valve, or a damaged impeller or casing. Troubleshooting methods include inspecting and cleaning the impeller and suction strainer, checking the discharge valve position, and inspecting the impeller and casing for damage.
- Low pump head: This can be caused by a worn or damaged impeller, a low suction pressure or vacuum, or a clogged suction strainer. Troubleshooting methods include inspecting the impeller for wear or damage, checking the suction pressure or vacuum, and cleaning or replacing the suction strainer.
- Excessive vibration: This can be caused by misalignment of the pump and motor, loose or damaged pump components, or cavitation. Troubleshooting methods include checking and correcting the alignment of the pump and motor, inspecting and tightening all pump components, and adjusting the pump speed or impeller diameter to prevent cavitation.
- Bearing failure: This can be caused by improper lubrication, excessive vibration, or a worn or damaged bearing. Troubleshooting methods include checking and adjusting the lubrication system, checking and correcting any sources of excessive vibration, and inspecting and replacing worn or damaged bearings.
- Leakage at the pump seal: This can be caused by worn or damaged seals, improper installation or adjustment of the seal, or excessive pressure or temperature. Troubleshooting methods include inspecting and replacing worn or damaged seals, checking and adjusting the seal installation and adjustment, and reducing the pressure or temperature if necessary.
- Excessive noise: This can be caused by cavitation, improper installation or alignment, or worn or damaged pump components. Troubleshooting methods include adjusting the pump speed or impeller diameter to prevent cavitation, checking and correcting the installation or alignment, and inspecting and replacing worn or damaged pump components.
- Overheating: This can be caused by a blocked or restricted cooling system, excessive pump speed or power, or improper lubrication. Troubleshooting methods include inspecting and cleaning the cooling system, reducing the pump speed or power, and checking and adjusting the lubrication system.
- Corrosion or erosion of pump components: This can be caused by exposure to corrosive or abrasive fluids, improper material selection, or poor maintenance practices. Troubleshooting methods include selecting the appropriate materials for the fluid being pumped, improving maintenance practices, and inspecting and replacing corroded or eroded pump components.
- Electrical problems: This can be caused by faulty or damaged electrical components, improper wiring, or improper electrical grounding. Troubleshooting methods include inspecting and replacing faulty or damaged electrical components, checking and correcting the wiring, and ensuring proper electrical grounding.
-
Impeller damage: This can be caused by solids or debris in the fluid, excessive vibration, or improper handling or installation. Troubleshooting methods include inspecting and cleaning the fluid for solids or debris, checking and correcting any sources of excessive vibration, and handling and installing the impeller properly.
- What is Gear Pump it’s Works and Applications
- Centrifugal Pump
- Cavitation in centrifugal pump
- Basics of reciprocating pump
- Types of Pumps: A Comprehensive Guide
- Centrifugal pump characteristic curves
- Troubleshooting of centrifugal pump New 1
- Characteristics of positive displacement pump
- Basic use of wearing rings in centrifugal pump
