Influence of ocean load on the axial force of coiled tubing under different buckling states

•An indoor experimental platform was built which can be used to study the influence of ocean load on axial force transmission characteristics of Coiled Tubing.•When the CT’s buckling state is the same, the greater the ocean load, the greater the axial force fluctuation.•When the ocean load is the same, the greater the CT’s buckling degree, the greater the axial force fluctuation.•The ocean load has little effect on the transmission efficiency but increasing the CT’s buckling degree significantly improves the transfer efficiency.