The difference between positive circulation and reverse circulation drilling rigs

The difference between forward and reverse circulation drilling rigs

1. The positive circulation means that the flushing fluid is sent to the bottom of the hole by the mud pump through the drill pipe, and then returns to the ground from the bottom of the hole; the flushing fluid of the reverse circulation is just the opposite of the route of the positive circulation.

Positive circulation rotary drilling: The mud is fed into the inner cavity of the drill pipe from the mud pool by the mud pump at high pressure, and is ejected through the mud outlet of the drill bit. When the drill bit at the bottom rotates, the soil layer is loosened to become drilling slag, which is suspended by the mud, overflows with the mud rising, and is purified by sedimentation in the sedimentation tank, and the mud is recycled.

Reverse circulation rotary drilling: The mud flows into the drilling hole from the mud pool and mixes with the drilling slag. Under the suction force of the vacuum pump, the mixture enters the slag inlet of the drill bit, passes through the inner cavity of the drill pipe, the debris pump and the slurry discharge control raft, and is discharged into the sedimentation tank for purification before being used. Reverse circulation drilling drills in soft plastic soil, loose sand, gravel, eggs, and cushion soil containing long wooden sticks, tree roots and other debris. When the mud performance is poor and the circulation flow (flow rate) is not good, it is easy to drill. A collapse occurred.

2. The mud circulation mode is different, and the rotary drilling machine is divided into positive circulation drilling and reverse circulation drilling. For positive circulation drilling rigs, the mud is pumped out from the supply pool by the mud pump, and the input hose is sent to the upper inlet of the faucet, and then injected into the head of the rotating hollow drill pipe, and then flows through the hollow drilling rig until it is discharged from the bottom of the drill bit. The rotating drill bit lubricates the mud, Spread the mud to the bottom of the hole, float to the top of the hole with the drill ballast, and overflow the mud groove on the ground from the top of the hole. The difference between the reverse circulation drilling rig and the positive circulation drilling rig is that when drilling, the mud is directly injected around the drill hole without a tap, the mud is lowered to the bottom of the hole, and the drill bit is mixed to make the slurry inside the hole evenly reach the expansion wall, lubricate the drill bit, and float the drill ballast. Compressed air is continuously sent into the faucet, through the fixed pipe to the top of the drill bit, and according to the principle of air suction mud, the drilling slag is discharged from the hollow drill pipe into the faucet hose to overflow.

The above is the difference between positive circulation and reverse circulation drilling rigs summarized for you

I hope it will be helpful to you, if you have any questions, please feel free to contact us,

Shandong Yikuang Drilling Technology Co., Ltd. is a large-scale professional manufacturer of high, medium and low wind pressure down-the-hole drilling rigs and water well drilling rigs in Shandong Province. The leading products include: water well drilling rigs, environmental sampling drilling rigs, core drilling rigs, pneumatic water well drilling rigs, geological Exploration drilling rigs and drill pipes, bits and accessories. The company has been committed to the professional production of water well drilling rigs and down-the-hole drilling rigs, and the sales and maintenance of drilling tools and air compressors for more than 20 years.

We welcome customers from all over the world to visit our factory for guidance. Follow the official website of Shandong Yikuang Drilling Technology Co., Ltd., and take you to learn more about down-the-hole water well drilling rigs.