Product Definition and Core Structure

Foam metal sand control screen is a new type of sand control completion tool for oil and gas production. It adopts three-dimensionally interconnected porous foam metal (nickel foam, alloy foam) as the core sand retaining filter layer, replacing traditional wire-wrapped screens, slotted liners and metal mesh screens. It is suitable for sand control scenarios of unconsolidated sandstone, heavy oil and offshore oil & gas wells.

Standard Multi-Layer Composite Structure (From Inside to Outside)

● Base pipe: Perforated carbon steel/stainless steel tubing, which bears the overall structure and serves as fluid flow channels;

● Inner foam metal: Large pore size (loose pores), used for fluid buffering and fine sand storage to reduce plugging risk;

● Outer foam metal: Small pore size (dense pores), the core sand retaining layer for accurate formation sand interception;

● Outer protective casing: Perforated protective pipe, which prevents scratching and damage to the foam metal filter layer during downhole running.

Main Substrate Options

● Nickel foam (industry mainstream): Resists corrosion from hydrogen sulfide and high-mineralization formation water, features high temperature resistance with porosity ranging from 60% to 90%, applicable to heavy oil and highly corrosive oil & gas wells;

● Alloy foam: Superior resistance to severe corrosion and high tensile strength, specially used for deep-sea and high-sulfur wells.

Sand Retention & Filtration Mechanism

● Large-sized formation sand is trapped on the surface by dense outer pores;

● Fine silt enters the internal 3D pore channels without fully blocking flow paths;

● Fluid can continuously flow through surrounding interconnected pores, delivering drastically improved anti-plugging performance and self-cleaning capacity compared with conventional screens.

Laboratory tests verify that the double-layer foam metal structure with dense outer pores and loose inner pores reduces displacement pressure differential by 40% under the same flow rate, avoiding production decline during long-term operation.

Core Performance Advantages

(vs. Stainless Steel Wire-Wrapped Screens & Metal Mesh Screens)

① Higher flow capacity

With porosity above 80%, its effective seepage area far exceeds that of slotted liners and wire-wrapped screens, boosting single-well liquid production by 20%~50%. Field test in heavy oil wells of Shengli Oilfield shows that after deployment, dynamic fluid level recovered by 130 m with daily liquid output reaching 54 m³.

② Anti-plugging capability for long-term stable production

No fixed narrow slits exist in the 3D pore structure, so clay and fine silt are unlikely to get stuck. Its maintenance-free service cycle is 2 to 3 times longer than conventional screens.

③ Erosion and wear resistance

Supported by a 3D metal skeleton, it resists perforation and damage under high-speed sand-laden fluid scouring, ideal for unconsolidated sandstone formations with severe sand production.

④ Wide corrosion compatibility

Nickel foam resists corrosion induced by H₂S and Cl⁻ ions, suitable for offshore wells and wells with high-mineralization and sulfur-bearing formation fluids; ordinary stainless steel screens are prone to pitting corrosion.

⑤ Customizable sand retention precision

Pore size can be customized from 0.05 mm to 10 mm, covering reservoirs with fine silt, medium and coarse sand. A single material adapts to formations with various sand grain sizes.

⑥ Simplified construction

Efficient sand control can be realized with a single screen pipe, eliminating gravel packing procedures for most working conditions and cutting completion costs.

Applicable Scenarios

① Onshore heavy oil unconsolidated sandstone oil wells: Large-scale field application in Shengli and Liaohe Oilfields;

② Offshore oil & gas fields: Deepwater, horizontal and extended-reach wells, solving the problems of easy plugging and high running friction of traditional screens;

③ Highly corrosive oil & gas wells: Wells with hydrogen sulfide and high-mineralization formation water (nickel foam is the preferred material);

④ Managed sand production wells: Allows trace fine sand passage while blocking coarse sand that damages pumps;

⑤ Geothermal wells and groundwater sand control exploitation.

Key Technical Parameters (Mainstream Nickel Foam Specifications)

● Porosity: 65%~85%

● Controllable filtration pore size: 0.08 mm~5 mm

● Single filter layer thickness: 3~8 mm; total thickness of double-layer composite: 6~12 mm

● Temperature resistance: -40℃ ~ 350℃

● Resistant media: Saturated brine, H₂S, CO₂ bearing formation fluids

● Tensile strength: ≥12 MPa (nickel-based foam alloy)

Disadvantages and Optimization Solutions

① Higher cost than ordinary stainless steel screens

Optimization: Adopt layered structural design combining thin large-pore nickel foam outer layer and small-pore nickel foam inner layer to balance anti-corrosion performance and manufacturing cost.

② Surface metal skeleton loss under long-term high-flow erosion

Optimization: Electroplate wear-resistant anti-corrosion alloy on the surface, or increase the thickness of outer foam metal layer.

③ High requirements for welding processing

Adopt TIG welding with Inconel nickel-based welding wire to ensure welds resist downhole corrosion and cracking.

Industrial Application Status

● Domestic: CNOOC, PetroChina, and Sinopec have completed multiple rounds of field tests; at a certain oilfield’s heavy-oil well, a cumulative total of 8,713 m³ of fluid was extracted without any significant blockages or failures;

● Technical trend: Gradient pore-size nickel alloy foam screens are gradually replacing metal wool and wire-wrapped screens, becoming the mainstream new technology for medium-to-high difficulty sand control completion.

● Supporting industrial chain: Screen deep-processing manufacturers provide integrated supply, supporting customized mass production for oilfields.