SU91593A2 - The method of protection of drill pipes from twisting with two motor drive of the drilling machine - Google Patents

Description

BASIC Auth. St. No. 80613 describes a method for protecting drill pipes from twisting when a drilling machine is driven by a multi-speed asynchronous motor by switching the engine when the bit is jammed in the generator mode by switching the winding to a lower number of turns (i.e., more poles).

The described invention relates to the case when the machine is driven by two asynchronous motors. According to the invention, with such a drive, the protection of the pipes from twisting is carried out by switching on induction motors in the cascade generator mode.

The drawing shows an engine control circuit for the proposed method.

To start the motors} and the 2 handwheels of the control PLC controllers, mechanically interconnected, are set to the neutral position. In this position, the contacts / C / and KJ are closed, and the PH coils of the relay become energized. The voltage relay of the PH closes its normally open block contacts PHJ and opens its normally closed block contacts PH2 in the supply circuit of the contactor 1 and the drifter 2.

When the controllers' control dials rotate, contacts K. and / C / i open, and contacts K2 close.

When the contacts K2 are closed, the contactor / U is turned on, which, with its normally open auxiliary contacts, 1U1 closes the power supply circuit of the acceleration relay 1RU. The power supply circuit of the forward coil and the reverse path of the second control station is open.

No. 91593-2 -

Simultaneously with the inclusion of the contactor 1U, the power supply circuit of the contactors controlling the motor auxiliary resistances / opens with the help of the block contacts U / 2. The engines are thus prepared for the transition to the first starting stage. Upon further rotation of the controls of the controllers, contacts K.4 in the control circuit of the first engine are closed, and the engines are switched on to the first starting stage in a cascade with an additional resistance R, and the rotor of the engine 2.

With the transition to the second stage, the contacts K2 are opened and de-energize the contactor IV and the acceleration relay 1RU. When the contactor IV is disconnected, its block contacts U12 in the supply circuit of the contactors of the additional resistances of the first control station are closed. When the acceleration relay 1RU triggers, its block contacts 1RU1 in the supply circuit of the forward and reverse contact contactors (B and H) of the second control station are closed with a time delay determined by the acceleration relay 1RU setting and prepare the circuit for the transition to the second start level.

In the second stage, contacts / C5i and K4 of the second control station and contacts / C5 of the first control station are closed.

When the contacts of L5 are closed, the contactor 2U is triggered without time delay, since the block contacts 2RU1 of the acceleration relay 2RU in the power supply circuit were previously turned on (when the acceleration relay 2RU was activated at the first starting stage).

The presence of the time delay of the accelerator relay 1RU and the block contacts 1RU1 in the supply circuit of the forward and reverse contactors of the second control station provides the necessary blocking them with the contactor / U and closing the zero point of the additional resistances of the first motor before the motors are connected in parallel to the network. Thus, the motor rotor circuit (during the entire start-up period) is closed either to the stator of the motor 2, or to additional resistances.

Further transition to 3, 4, and 5 start stages (relay switchgear and 4RU relays occur at simultaneous closure of contacts K, 5 and K.6; K6i and K7; L71 and K8.

If during the drilling of a well, the bit was jammed and the drilling motors started to twist the drill pipes, then when the load reaches above the installation of the current relay RK. U, the latter will work and the LV voltage relay will open with its block contacts. After some time, determined by setting the time delay, the voltage relay will operate. Its blocking contact PH1 is open and the blocking contact PH2 is closed in the supply circuit of contactors 1U and 2U of the second control station. In this case, the stator power supply circuit of the engine 1 is not interrupted due to the presence of a jumper of the PH contact terminals in the power supply value of the forward contactors or the reverse direction of the first control stage.

After opening the forward or backward contacts and closing the B or I contacts in the contactor / V supply circuit, the latter will turn on and switch motor 2 into a motor stage. Opening the forward or backward contactors of the motor 2 will open the power supply circuit of the contactors of the charger and 4U. The power supply circuit of contactor 2U also opens, but is immediately switched back on by the PH2 contact.

When the engine 2 is turned on in a cascade with a motor / contactor / V, it simultaneously breaks the supply circuit of contactors 1U, 2U, charger and 4U in the rotor circuit of engine 1 with its normally closed contact contacts U1, and the motors are in the cascade generator mode with the required amount of additional resistance motor rotor chains 2.

Non-automatic transfer to the cascade generator mode during jamming of the bit can be accomplished by simply turning the controls of the controllers and setting them in the first stage of the starting circuit of the engines.

Switching the motors to normal operation is also performed by simply turning the controls.

The number of revolutions of the engine during drilling at low bit rates can be reduced by half without loss of energy in incremental resistances by switching the engines into a cascade. To do this, you need to transfer the controller wheel to the first stage and by pressing the auxiliary button / (remove the additional resistance from the rotor circuit of the second engine using the contactors and 4U contactors. As you know, the total power of two identical motors included in the cascade will be equal to power of one engine.

Subject invention

The method of protecting drill pipes from twisting with a twin-engine drive of a drilling machine according to the author. St. No. 80613, characterized in that when the bit is jammed, asynchronous motors are switched on in a cascade generator mode.

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