High-pressure bit nozzle

FIELD: mining.

SUBSTANCE: high-pressure bit nozzle is made in the form of confuser with straight-line channel section. Nozzle diametre do is chosen depending on density of flushing fluid, supply of drilling pump, nozzle resistance coefficient, nozzle opening degree, flow coefficient of supply channels, flow coefficient of nozzle, number of nozzles in the bit, the pressure created with the drilling bit, and length of straight-line nozzle section is determined by the formula ℓ=Kd0, where ℓ - length of straight-line channel section; K - trial coefficient (K=0.51÷0.53). Wear resistance of the material of the working nozzle part is higher than wear resistance of the material of its rest part.

EFFECT: increasing the drilling efficiency and reducing the cost of the drilling process.

 

The technical solution relates to the mining industry, and is intended for flushing the drill bit.

Known nozzle jetting bits made in the form of confusor (see USSR author's certificate, M CL EW No. 1609937). The disadvantage of this nozzle is that it lacks a clear straight section of the channel of the nozzle, and the diameter of the nozzle is selected irrational, which reduces jetting effect and efficiency of rock breaking and removal of sludge from the bottom.

The closest analogue is the jetting nozzle of the drill bit in the form of a confuser with a straight section of the channel (see Macovei N. Hydraulics drilling. TRANS. with the ROM. - M.: Nedra, 1986 - 536 S.).

The disadvantage of this nozzle is the lack of a rational choice of the diameter of the nozzle and the length of the straight part of the channel of the nozzle.

Technical solution aimed at improving jetting effect and efficiency of rock breaking and removal of sludge from the bottom by a rational choice of the diameter of the nozzles of the bit and the length of the straight part of the channel of the nozzle.

The solution of this problem is provided by the fact that the jetting nozzle of the drill bit in the form of a confuser with a straight section of the channel diameter of the nozzle is determined by dependencies

where do- the diameter of the nozzles of the bit;

ρ W- the density of the drilling fluid;

Q - flow mud pump;

eabout- coefficient of resistance of the nozzle (eabout=1,1-1,4);

m is the degree of expansion of the nozzle (m=0,30-0,55);

µKthe coefficient of discharge of the inlet channels (µK=0,85-0,90);

µothe coefficient of discharge nozzles (µo=0,85-0,95);

Z is the number of bit nozzles;

Pδthe pressure created by the drilling pump,

and the length of the straight part of the channel is determined by the formula

l=do,

where l is the length of the straight part of the channel;

dabout- the diameter of the nozzles of the bit;

to - pilot ratio (or=0.51-0,53),

thus the wear resistance of the material of the working part of the nozzle is higher than the wear resistance of the material to its rest.

Due to the fact that dependence for determining the diameter of a nozzle is

,

where do- the diameter of the nozzles of the bit;

ρW- the density of the drilling fluid;

Q - flow mud pump;

eabout- coefficient of resistance of the nozzle (eabout=1,1-1,4);

m is the degree of expansion of the nozzle (m=0,30-0,55);

µKthe coefficient of discharge of the inlet channels (µK=0,85-0,90);

µothe coefficient of discharge nozzles (µo=0,85-0,95);

Z is the number of bit nozzles;

Pδthe pressure created by the drilling pump.

There is the possibility of using the AMB rational value of the diameter of the nozzle depending on the supply mud pump and pressure develop them.

Due to the fact that the length of the straight part of the channel is determined by the formula l=do,

where l is the length of the straight part of the channel;

do- the diameter of the nozzles of the bit;

to - pilot ratio (or=0.51-0,53),

during drilling with the passage of drilling fluid along the straight section of the channel of the nozzle is formed of a compact jet of liquid, which is at the end of the nozzle effectively destroys the rock. This helps to improve the mechanical drilling speed.

When the value of K equal 0,51-0,53, formed the maximum coefficient of discharge nozzles, thereby increasing the rate of fluid outflow from the nozzle and the mechanical drilling speed.

When the value of K less 0.51 to increase the speed of fluid outflow does not occur, and when it is more 0,53 there is increased wear of the nozzle.

Due to the fact that the wear resistance of the material of the working part of the nozzle is higher than the wear resistance of the material of the remaining part, significantly reduces abrasive wear of the nozzle on its working parts. This increases the service life of drill bits and drilling rate them.

Increased wear of the working parts of the nozzle is achieved by a coated wear-resistant composition.

The drawing shows a longitudinal section of the nozzle gidravlicheskogo the bit, which is the working part 1, the area of increasing the wear resistance of the working part of the nozzle 2, the diameter of the inlet channel to the nozzle DTothe diameter of the nozzle daboutthe length of the straight part of the channel of the nozzle l, the length of the nozzle L.

The nozzle operates as follows.

During the drilling of the flushing fluid from the input channels bit with diameter DKenters the working part of the nozzle 1 (confuser channel) and due to rational values of the degree of disclosure of the nozzle and gradual narrowing of the channel gains haste and enters the straight portion of the channel, where the rational length of this part of the channel and increased wear resistance of the working part is formed of a compact jet, which runs from the nozzle with diameter dowith high reserve of kinetic energy. Hitting the bottom with a high speed liquid jet erodes rock bottom and improves cleaned of sludge, thereby increasing the mechanical drilling speed.

This solution can be implemented by means described in the application of funds. It was implemented in the construction of injection wells on .XXVII mining and chemical combine Zheleznogorsk.

Technical and economic efficiency of the proposed utility model is to improve the performance of drilling and reducing the cost of drilling 1 p. is. 200 rubles

The jetting nozzle of the drill bit in the form of a confuser with a straight section of the channel, characterized in that the diameter of the nozzle is determined by the dependence of

where d0- the diameter of the nozzles of the bit;
ρW- the density of the drilling fluid;
Q - flow mud pump;
e0- coefficient of resistance of the nozzle (e0=1,1÷1,4);
m is the degree of expansion of the nozzle (m=0,30÷0,55);
µKthe coefficient of discharge of the inlet channels (µK=0,85÷0,90);
µ0the coefficient of discharge nozzles (µ0=0,85÷0,95);
Z is the number of bit nozzles;
Pδthe pressure created by the drilling pump
and the length of the straight part of the channel is determined by the formula
l=d0,
where l is the length of the straight part of the channel;
d0- the diameter of the nozzles of the bit;
to - pilot ratio (K=0,51÷0,53),
thus the wear resistance of the material of the working part of the nozzle is higher than the wear resistance of the material of the remaining part.



 

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5 cl, 2 dwg

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