What is an OH6 Centrifugal Pump? Explained in One Article

If you work in industries like chemical, petrochemical, power, or water treatment, you’ve probably heard of the OH6 centrifugal pump. It’s not a new device, but a classic industrial pump designed in accordance with API 610 standards—featuring reliable structure and easy maintenance, it’s particularly suitable for continuous transfer tasks involving medium-high pressure and medium flow.

Below, we’ll use plain language to quickly explain what it is, its advantages, and its applications from five aspects.

1. What Does OH6 Stand For?

• "OH" = Overhung Horizontal pump
• "6" = The 6th structural type specified in API 610 standards

Simply put: The motor is on one side, the impeller is overhung on the shaft with no intermediate bearings, resulting in a compact structure that’s easy to disassemble and assemble. The pump casing is volute-type, mostly equipped with mechanical seals, and the material can be cast iron, stainless steel, or even duplex stainless steel—handling corrosion and high temperatures with ease.

2. How Does It Work?

It operates on a proven, stable principle:The motor drives the impeller to rotate at high speed → The liquid is thrown outward → Velocity is converted into pressure in the volute → High-pressure liquid is discharged from the outlet, while new liquid is sucked into the center of the impeller → The cycle continues.

Both flow rate and pressure can be adjusted via valves or frequency conversion, flexibly adapting to different working conditions.

3. Why Is OH6 So Popular?

• High efficiency: Saves 5% to 10% more electricity than ordinary pumps, resulting in significant long-term energy cost savings.
• Long service life: Simple structure and low vibration allow continuous operation for over 8,000 hours without issues.
• Strong adaptability: Capable of transferring clean water, oil, acid-alkaline solutions, etc., with a temperature range of -40℃ to 200℃ and pressure resistance up to several megapascals.
• Easy maintenance: Horizontal installation means no need to modify pipelines during repairs; replacing seals and bearings is straightforward.

4. How Does It Differ from Other Pumps?

• More pressure-resistant than OH1/OH2: OH1 and OH2 are mostly used for low pressure and small flow, while OH6 is specifically designed for medium-high pressure with a more robust structure.
• Easier to repair than vertical pumps: Vertical pumps save space but require pipeline disassembly when faulty; OH6’s horizontal design provides ample space for quick maintenance.
• More standardized than ordinary chemical pumps: OH6 complies with API 610 international standards, featuring universal spare parts and controllable quality—ideal for industries like petrochemicals with strict equipment requirements.

5. Where Is It Actually Used?

• Petrochemical plants: Transferring crude oil or chemical materials at 120℃, stainless steel OH6 pumps operate continuously for a year without failure while saving energy.
• Water treatment plants: Need 120m head for reverse osmosis systems? OH6 provides stable pressure with consistent flow and low vibration, protecting reverse osmosis membranes from damage.
• Power plants: Boiler feed water at 180℃ and 2.0MPa? High-temperature OH6 pumps with forced lubrication have operated continuously for two years.
• Chemical plants: Transferring chlorine-containing corrosive liquids? Duplex stainless steel OH6 pumps with enhanced seals only require maintenance every six months.

In a Nutshell:

The OH6 centrifugal pump isn’t the most fancy, but it excels in durability, efficiency, easy maintenance, and uniform standardization. If your working conditions involve medium-high pressure, continuous operation, and reliability, it’s likely a solid choice.

For more industry-related information, please visit www.teffiko.com