KSB's RPH series is a classic API OH2 pump. This article introduces its structure and industry applications.

KSB's RPH series is indeed a globally recognized exemplary process pump conforming to the API 610 OH2 standard. It is designed for continuous, safe, and efficient operation under harsh conditions in heavy industries such as petroleum and chemical processing, and is renowned for its robustness, high reliability, and ease of maintenance.

Below, I will provide a detailed introduction from three aspects: structural features, core parameters, and industry applications.

🛠️ Structural Features: How to Define the "Heavy-Duty" Benchmark?

The RPH series is designed strictly according to API 610/ISO 13709 standards. Every detail of its structure is designed to meet the challenges of high temperature, high pressure, and continuous operation.

Compliant with API 610 OH2 Standard: This is its fundamental positioning. The RPH is a horizontal, radially split, single-stage, single-suction, cantilever centrifugal pump. Compliance with this standard means that it adheres to strict specifications throughout its entire lifecycle, including design, materials, manufacturing, and testing, and is specifically designed for heavy-duty applications.

Centerline Support Design: The pump body employs centerline support, with the pump feet located on the horizontal plane of the shaft centerline. This design ensures that when conveying high-temperature media, the pump body expands evenly along the centerline, preventing shaft misalignment or alignment failure, thus guaranteeing operational stability and sealing reliability.

Back Pull-Out Design: This is another core design feature of RPH pumps and a typical characteristic of API pumps. During maintenance, the pump body and inlet/outlet pipes can be removed without disassembling the pump body; simply removing the coupling allows the entire bearing housing, along with the impeller, shaft, and mechanical seal, to be pulled out from the rear. This greatly simplifies maintenance and reduces downtime.

Double Volcanic Chamber Design (from DN80): Starting with certain diameters (DN80/3 inches), RPH pump bodies utilize a double volcanic chamber structure. This design effectively balances the radial forces generated by the impeller during operation, significantly reducing shaft deflection and thus extending the service life of bearings and mechanical seals, ensuring long-term stable operation.

Heavy-duty bearings and sealing chamber: The bearing support features integrated cooling fins, aiding in heat dissipation at high temperatures and reducing bearing temperature. The sealing chamber strictly complies with API 610 standards, accommodating various API-compliant mechanical seal solutions, and can be equipped with a heated pump cover for high-temperature applications.

Optional inducer: For applications with stringent NPSH requirements, the RPH can be equipped with an inducer to effectively improve pump suction performance and prevent cavitation.

📊 Key Parameters: The RPH series offers a wide range of specifications, and also includes the RPH-LF model specifically designed for low-flow/high-head applications. Here is an overview of its core parameters:

Parameter Dimensions: RPH (Standard Type) RPH-LF (Low Flow Type)
Maximum Flow Rate: 4800 m³/h 49 m³/h
Maximum Head: 270 m 488 m
Maximum Working Pressure: 110 bar 110 bar
Medium Temperature Range: -70°C to +450°C -70°C to +200°C
Main Materials: Various metal materials are available depending on the corrosiveness of the medium, such as ASTM A216 WCB, CF8M, etc. (Same as above)
Explosion-proof Rating: ATEX explosion-proof certified version available. (ATEX explosion-proof certified version available)

🌍 Industry Applications
The RPH series is used throughout multiple stages of the oil, gas, and chemical industry chain, playing a crucial role, especially in the upstream and midstream sectors.

Application Areas | Specific Stages/Scenarios | Typical Media/Uses

Oil and Gas Industry (Core Area): Upstream production, midstream transportation and storage, various refinery process units | Crude oil, hydrocarbons, brine, liquefied petroleum gas, gasoline, diesel, fuel oil, etc.

Chemical and Petrochemical Industry: Basic chemical and fine chemical units | Acids, alkalis, solvents, ammonia, urea, and other chemicals

Power Industry: Power plant auxiliary systems | Boiler feedwater, hot water circulation, etc.

Specific Industrial Processes: Airport refueling facilities, sulfur production units, catalytic reforming and cracking, iron and steel and non-ferrous metal smelting | Aviation fuel, high-temperature hot water (such as RPH-HW model), process fluids

💡 Summary
The KSB RPH series is a heavy-duty single-stage cantilever centrifugal pump built strictly according to API 610 standards. Its key designs, such as centerline support, pull-back structure, and double vortex chamber, give it excellent long-term, stable, and safe operation capabilities under harsh conditions such as high temperature, high pressure, and corrosiveness. Whether in core refining and chemical plants, or in upstream mining and midstream transportation, RPH has become the trusted first choice for many engineers in critical process flows thanks to its extremely high reliability and global service network.

Are you currently selecting a pump for a specific refining and chemical project, or looking for a replacement pump for an existing plant? Tell me the specific operating parameters such as the medium, flow rate, and head, and I can help you further analyze whether the RPH series is the most suitable choice.