Depamu Injection Pumps for the Exploration and Production (E&P) Sector

Introduction

The exploration and production (E&P) sector of the oil and gas industry operates under some of the most demanding conditions imaginable. From the extreme cold of Arctic gas fields to the corrosive, high-humidity environments of offshore platforms in the South China Sea, the equipment deployed in these settings must perform reliably under constant pressure. Among the most critical pieces of equipment in any E&P operation are injection pumps—devices responsible for precisely dosing chemicals that prevent corrosion, inhibit hydrate formation, enhance oil recovery, and maintain the integrity of production infrastructure. Depamu, a Chinese pump manufacturer headquartered in Hangzhou, has emerged as a significant player in this space, supplying Metering Pumps, high-pressure Reciprocating Pumps, and complete chemical Injection Packages to oil and gas projects across the globe.

Company Background and Manufacturing Capabilities

Depamu (Hangzhou) Pumps Technology Co., Ltd. was established in 2003 and is located in a national-level economic and technological development zone. The company occupies a 35,000-square-meter facility with registered capital of 54 million yuan and employs over 200 people. Its core product portfolio includes metering pumps, High-Pressure Reciprocating Pumps (plunger, diaphragm, and hose types), electric Diaphragm Pumps, pneumatic diaphragm pumps, Screw Pumps (single, double, and triple), lobe pumps, as well as complete chemical dosing systems and water treatment equipment.

Depamu has positioned itself as a technology-driven enterprise, investing no less than 6% of annual sales revenue into research and development. To date, the company has obtained 126 patents, including 38 invention patents, and has been recognized as a national-level "little giant" enterprise specializing in niche sectors. Its products are exported to more than 20 countries, including Russia, the Middle East, and South America. According to industry association statistics, Depamu holds a 47% share of the domestic Chinese market for metering pumps and ranks among the top three globally in the metering pump and reciprocating pump sectors.

Product Portfolio for E&P Applications

Depamu's product line for the E&P sector is built around two primary categories: Chemical Injection Packages and high-pressure reciprocating pumps.

Chemical Injection Packages

Chemical additive injection packages are modular systems designed to deliver precise quantities of chemicals into oil and gas production streams. Depamu's injection packages are categorized according to the type of chemical being injected and include demulsifier injection packages, corrosion inhibitor injection packages, deoxidant injection packages, germicide injection packages, and methanol (CH₃OH) or ethylene glycol (CH₂OH)₂ injection packages, among others.

Each package is composed of a solution tank, mixer, metering pump, level gauge, safety valve, pressure gauge, pulsation damper, various valves, support base, stairway with handrail, circuit control components, and a complete piping system. The systems can be controlled locally and manually or automatically, with automatic control regulating the injection pump's output flow based on the injection volume indicated by a flowmeter at the injection port. All signals related to pump and mixer status and faults can be transmitted to a DCS or host computer for remote monitoring and control.

The solution tanks can be fabricated from 316 or 304 stainless steel, carbon steel, carbon steel with rubber or plastic lining, FRP, or PE, depending on the corrosiveness of the chemicals being handled. Tank volumes for oil and gas field applications range from 0.5 to 20 cubic meters, with metering pump capacities spanning 10 to 500 liters per hour and discharge pressures reaching up to 4.0 MPa for standard configurations.

High-Pressure Reciprocating Pumps

For applications requiring higher pressures and larger flow rates, Depamu offers a range of high-pressure reciprocating pumps designed in accordance with American Petroleum Institute standard API 674. These pumps are available in plunger, diaphragm, and hose configurations and are engineered to handle the most severe working conditions.

The HD series pumps, for instance, feature flow ranges from 3.37 to 78.99 cubic meters per hour and pressure ranges from 3.0 to 83.5 MPa, making them suitable for water injection, polymer injection, alcohol injection, and a range of chemical and fertilizer process applications. These pumps are particularly valued for their leak-free operation when handling toxic, flammable, or abrasive media—a critical requirement in oil and gas production where chemical leakage poses both environmental and safety risks.

Depamu's diaphragm reciprocating pump technology is notable for replacing traditional plunger reciprocating pumps in many applications. The company claims to be the only manufacturer in the world producing this particular type of diaphragm pump, which it says leads the global market in diaphragm reciprocating pump technology.

Applications Across the E&P Value Chain

Injection pumps serve distinct functions at different stages of the E&P process, from drilling through primary, secondary, and tertiary recovery.

Drilling and Exploration

During the exploration and drilling phase, injection pumps are used to deliver drilling fluid additives that enhance drill cutting removal and protect formations. While Depamu's primary focus is on production-phase injection, the company's metering pump technology is applicable to drilling fluid conditioning and wellbore treatment.

Primary Recovery: Flow Assurance and Asset Integrity

In primary recovery, the most critical injection applications involve flow assurance and infrastructure protection. Methanol and monoethylene glycol (MEG) injection is essential for hydrate prevention in both production tubing and flowlines, particularly in deepwater and cold-climate operations. Corrosion inhibitor injection protects production tubing and flowlines from the corrosive effects of produced fluids, while scale inhibitor dosing prevents mineral deposition in downhole and topside equipment. Demulsifier injection aids in the separation of oil-water emulsions, and H₂S scavenger injection is required in sour service environments.

Depamu's chemical injection packages are designed precisely for these applications. The company's injection packages for petroleum and natural gas exploitation, gathering and transportation, and oily sewage treatment cover demulsifier, corrosion inhibitor, deoxidant, reverse demulsifier, germicide, methanol, and ethylene glycol injection, with solution tank volumes ranging from 0.5 to 20 cubic meters.

Secondary and Tertiary Recovery: Enhanced Oil Recovery

In secondary and tertiary recovery, water injection and polymer injection become the primary mechanisms for maintaining reservoir pressure and mobilizing additional oil. Depamu's high-pressure reciprocating pumps are explicitly designed for these applications, serving as oilfield Water Injection Pumps and polymer injection pumps. The company signed the world's largest Indian oilfield polymer high-pressure reciprocating pump project in 2018, a contract that broke the monopoly previously held by European and American manufacturers in this high-end equipment segment.

Case Studies: Depamu in Action

Arctic LNG 2 Project, Russia

One of Depamu's most significant international references is the Arctic LNG 2 project in Russia, operated on the Utrenneye field on the Gydan Peninsula. The field holds proven reserves of nearly 1.4 trillion cubic meters of natural gas and 90 million tons of liquid hydrocarbons. The project is located in an extreme cold zone, imposing exceptionally high requirements on media transportation.

Depamu supplied high-pressure process diaphragm pumps and Hydraulic Diaphragm Metering Pumps designed specifically for the project's extreme cold conditions and special medium transportation requirements. The equipment was required to simultaneously satisfy performance criteria for flow rate, pump efficiency, stability, and temperature. The Russian owner and third-party inspection agencies gave unanimous positive feedback on the delivered equipment.

Notably, the previous Arctic LNG 1 project had sourced its fluid equipment from an American supplier. Depamu's selection for Arctic LNG 2 signaled that Chinese pump technology had reached a level competitive with established Western manufacturers.

CNOOC FPSO Water Injection Project, South China Sea

For CNOOC's floating production, storage, and offloading (FPSO) vessel operating in the South China Sea, Depamu delivered a super-large flow, ultra-high-pressure water injection pump system driven by an 800 kW motor. The system achieves a maximum working pressure of 30 MPa and a single-unit daily water injection capacity of 2,000 cubic meters, meeting the secondary oil recovery requirements of offshore oilfields.

The system incorporates a PLC-based control system enabling real-time closed-loop regulation of pressure, flow rate, and temperature, with a fault warning accuracy of no less than 99%. The equipment has been certified to API 674 and DNV-GL standards, with salt-spray corrosion-resistant design ensuring stable operation in the high-temperature, high-humidity environment of the South China Sea.

Offshore Platform Chemical Injection Skids

Depamu has also successfully delivered multiple sets of offshore platform chemical injection skid equipment and high-pressure reciprocating pumps to CNOOC for deployment in the South China Sea and Bohai Sea. Faced with the severe space constraints of offshore platforms, Depamu's engineering team adopted an innovative three-tier skid structure that arranges ton tanks, storage tanks, and pump groups in a vertical configuration, reducing the footprint by 40% to 50% compared to traditional designs.

This "space-saving" design not only addresses the platform's spatial limitations but also leverages height differences to reduce pump cavitation risk and extend equipment service life. To withstand the highly corrosive marine environment, the team optimized welding processes, applied full-penetration welds to critical steel structure components, and upgraded to corrosion-resistant materials including duplex stainless steel and titanium.