Steel pipe with sharp end and perforated threading

Steel flower pipe is a construction method used in tunneling and slope support treatment projects during excavation, primarily employed for pre-supporting in soft and broken zones, shallow burial sections, bias-loaded tunnel mouth sections, sand layers, sand cobblestone layers, and fault broken zones during the self-stabilizing period.

Steel flower pipe is a highly effective auxiliary construction method for stable excavation work. In the construction of soft and broken rock strata, the advanced small diameter pipe plays a reinforcing role in loose rock formations. After grouting, it enhances the stability of loose and soft surrounding rocks, benefiting the stability of the surrounding rocks after excavation and during the initial support period, preventing instability, damage, and collapse of the surrounding rocks.

The steel flower pipe grouting is suitable for soft surrounding rock in tunnel arches, loose, unbound soil layers, poorly self-stabilizing sand layers, and broken rock layers composed of sand and gravel (cobble) stones.

Ensure the processing of steel flower pipes is meticulous. Typically, construction involves using straight seam or seamless steel pipes, with a diameter of 108mm. The wall thickness of the steel flower pipes is 6mm. Upon manufacturing, the standard length of the pipes is usually between 6 to 8 meters. During construction, welding is required. The total length of the steel pipes needed can be determined based on measurement results and CNC calculations, and then proceed with the processing once the data is confirmed.

Due to the need for the steel flower pipe to withstand shear forces in the slope rock mass during construction, this reduces damage during grouting. To prevent the steel flower pipe from directly contacting the residual debris at the bottom of the borehole during bracket welding, a bracket must be welded at the bottom. Double-sided welding should be used during the welding process, and watering should be avoided; natural cooling is sufficient.

Steel flower pipe manufacturing generally follows customer specifications for customization. The standard production involves one end being pointed, with the point extending several centimeters, while the other end is either plain or threaded. The standard drilling requirements are divided into two types: one involves drilling three rows of holes, with the spacing between rows being several centimeters and the hole diameter specified. The other type is drilling four rows of holes, with the spacing within the same row being several centimeters and the hole diameter specified.