Standard inner barrels

Reservoir Group offers a range of standard inner barrels for all of our core barrel platforms. Unlike our Thin Sleeve System (TSS), which has reusable components, these inner barrels are disposable, which reduces the amount of handling and disturbance to the core itself when recovered on surface.

Features and Benefits

• Ease of core entry due to lower friction than conventional steel inner barrels
• Reduction in core jamming and longer core runs due to lower friction co-efficient
• Improved recovery rates
• Enhanced recovery of friable and unconsolidated formations
• Recovery of undisturbed cores of improved quality
• Reduction of on-site core processing


Aluminium is now our most widely used standard disposable inner barrel. It is available with either a smooth or fluted ID, which aids in the gas release during tripping.
Features and Benefits

• Aluminium withstands high downhole temperatures and will operate with high compressive loads.
• Aluminium is less likely to suffer from structural damage.
• Can be fitted with pressure relief plugs to enable evacuation of unwanted gas.
• Excellent Value for money.

Glassfibre Reinforced Plastic (GRP)

The GRP inner tube is made from fibrous strand rovings, which are impregnated with epoxy resin and helically wound, under tension, onto a polished mandrill. This material and the method of manufacture gives the GRP tube a polished internal wall.

Features and Benefits

• Low co-efficient of friction due to polished internal wall, which allows smooth transfer of core into the inner tubes.
• Reduction in the risk of core jamming and consequently higher core recovery is attained.
• Resistant to the corrosive effects of acids, salts and other chemicals often used in drilling fluids.
• Due to the non-toxic properties, core samples can be safely stored in GRP sections. 
• GRP tube is strong and lightweight, allowing easy handling on the rig site.