Rental of Rotary Drilling Rig: Key Points in the Whole Process of Pile Foundation Construction

Rotary drilling rig rental: pile foundation construction preparation should be based on the characteristics of the construction site, the site is flattened and compacted as a construction platform. Determine pile location and ground elevation. When setting out the pile position, the deviation of the pile position shall be within the scope allowed by the specification, and the pile protection shall be set at 2m away from the pile center to check the pile center and elevation at any time. Each rig is equipped with a test line to check the borehole depth at any time. The casing is made of 6mm thick steel plate, and the inner diameter is 20cm larger than the pile diameter. The top of the casing shall be 30cm higher than the ground, and the length of the casing shall not be less than 1.2m. Check whether the pile center position is correct after the pile casing is set out and the pile is embedded.

Rotary drilling rig rental: what are the technical requirements for pile foundation construction concrete?

The first is the slump: requirements of concrete into the pump slump 180 ㎜ ~ 220 ㎜, slump is too large, the concrete may shrink, the structure is easy to crack; too small, affect the concrete construction performance, it is difficult to ensure the quality of concrete construction.

The second is workability: the concrete has good workability, good water retention, no segregation, no bleeding, which is conducive to the construction to ensure the quality of concrete.

Rental of rotary drilling rig: finally, setting time: in order to ensure continuous concrete pouring and avoid cold joints during construction, the initial setting time of commercial concrete is required to be more than 6 hours.

Pore formation process in pile foundation construction. Pile foundation positioning measurement: guide the measurement of pile foundation coordinates and elevation according to the measurement anchor points handed over on site, and mark and number them after verification. Excavation and burying of protection cylinder: before drilling, in order to ensure the stability of facilities and the hole is not skewed, round steel protection cylinder shall be buried underground with a burial depth of not less than 1.00m, and the deviation between the center of protection cylinder and the center of pile position shall not be less than 5cm. The steel casing is made of a steel plate with a thickness of more than 8mm, and an overflow hole is arranged on the upper part.

Rotary drilling rig rental: after the impact drilling is in place, the center of the punch should be aligned with the center of the casing. Within the stroke range of 0.4~0.8m, the compaction should be low, and stone and mud wall protectors should be added in time. When the protection cylinder is submerged 3~4m, the stroke can be increased to 1.5~2.0m, and the normal impact can be transferred at any time to measure and control the relative density of the mud. During the construction process, always check the damage of the wire rope, the tightness of the clamping machine and the flexibility of the steering device to avoid falling out of the drill bit.

Rental of rotary drilling rig: the pile foundation construction mud circulation system consists of mud tank, settling tank, circulation tank, non-mud tank, mud conveying pipeline and drilling slag separation device, and shall have drainage, waste mud discharge and external conveying channels. Mud tanks should be built in a place that is convenient for cleaning and does not affect the construction site. The volume should be greater than 1.5 times of the borehole volume. There should be more than two mud tanks to ensure that slag can be removed and used in turn under the condition of continuous drilling. The volume of each sedimentation tank is not less than 6m ³; The size of the waste slurry tank depends on the field of view and is generally not less than the volume of the borehole. Clay shall be used to prepare mud, and the drilling slag shall be removed frequently during use, and the viscosity, specific gravity, sand and colloid rate of the mud shall be measured so as to adjust the performance of the mud at any time.