Substantiation of rational repair technology of NBT-600 drilling pump

Contents

CONTENTS

Introduction

Purpose, arrangement and description of the specified equipment operation

Types and periodicity of equipment maintenance and repair

Description of possible defects

Drilling pump disassembly diagram

Choosing a Rational Part Recovery Technology

Calculation of lubricant quantity per year. Lubrication card

Instructions for safety measures

Conclusion

List of literature

Introduction

To clean the bottom of the well from the drilled rock, the drilling rig is equipped with a hydraulic system, which consists of drilling pumps, an injection pipeline, equipment for cleaning and collecting drilling fluid. In this system, drilling pumps are converters of mechanical operation of drive motors into hydraulic energy of drilling fluid flow, which is necessary for removal to the surface of drilled rock.

Currently, drive piston pumps of various designs are widely used. Steam direct pumps were replaced by double-piston pumps of double-sided action and three-piston single-sided action. Despite the more complex design than direct-acting steam pumps and the greater unevenness of supply, these pumps are more economical and widespread in drilling rigs. Also, compared to centrifugal, piston pumps have large dimensions, while they are able to provide large heads. Their supply does not depend on the head, which allows them to be used as dosing pumps. The efficiency of piston pumps is also higher than that of centrifugal pumps.

The costs of hydraulic energy during drilling are very large and with an increase in the depths of wells there is a tendency to increase them. Drilling pumps are the main energy consumers in the drilling industry and currently their driving capacity is 190-1250 kW.

Drilling technology does not allow the drilling fluid to stop circulating, so two pumps are provided in the drilling rig, one of which is redundant, to ensure the reliability of the process. For deep drilling by downhole motors, two pumps operate on a parallel switch-on. In this case, a third standby pump is usually installed.

Drilling pumps are operated under very difficult conditions. They pump viscous solutions, usually prepared on the basis of clay-aqueous mixtures and weighed with additives of hematite or barite. The solutions contain up to 2% abrasive particles of the rock and are pumped

pumps at a temperature of 40-70 ° С.

Aqueous solutions at this temperature are most corrosive. In addition, they often contain active chemicals: lime, caustic soda, tannic acids, salts and other substances.

Drilling pumps shall ensure sufficient uniformity of supply, be safe in operation, easy to maintain and repair in the field. A drilling pump is usually the heaviest unit of a drilling rig. The mass of modern most powerful pumps reaches 50 tons, so its design should allow transportation both by vehicles and by fibre within the field.

Even under normal operating conditions, the service life of quick-wear parts is limited to one hour:

pistons 100-200; rods 150 - 200; cylinder bushings 200-300; valves 300-400. Sometimes the service life of these parts is reduced to several tens of hours. Therefore, the speed and convenience of their replacement, as well as the low labor intensity of operations, are of great importance.

When designing drilling pumps, the metal flow rate per 1 kW of hydraulic (useful) power is of the utmost importance. This figure for modern double-acting double-cylinder pumps is 35-55 kg/kW. Usually, no powerful foundations are built under drilling pumps, so the total weight of the pump also increases to prevent large vibrations with increasing power. Among other advantages of three-cylinder single-acting pumps (triplexes), this figure is significantly reduced and amounts to 22-35 kg per 1 kW of hydraulic power. Moreover, with an increase in drive power from 600 to 1180 kW, the relative metal consumption decreased from 35 to 22 kg/kW.

Purpose, arrangement and description of the specified equipment operation

Three-piston drilling pump NBT750 is designed for injection of flushing fluid under pressure into the well during exploration and production drilling, as well as for pumping of drilling and other solutions for household needs and other purposes (for example, pumping of mortar to cementing units during cementation).

The pump is produced by the plant in several versions. Basic model (Fig.1) consists of hydraulic part 4, frame 3, drive part 2 and lubrication system 1.

The main difference between this pump and the most common double-cylinder pumps is the presence of three cylinders with one-way pistons.

The main feature of this pump is the speed of the pistons and therefore it is mandatory to install a centrifugal retaining pump with a supply of at least 50 DmZ/s in the suction pipeline.

The pump supplies flushing fluid through the drill string to the bottom of the well to cool the bit and carry the rock broken by the bit, as well as transfer the energy of the flushing fluid flow to the bottom-hole motor and the associated bit.

Water or clay solution with presence of oil, alkali, soda and other components is used as washing liquid.

Optimum drilling modes are provided by installation of cylinder bushings and pistons of one of sizes from 120 to 180 mm and control of number of drilling pump moves.

The drive part (Fig. 3) is designed to convert the rotation energy of the transmission shaft into the reciprocating energy of the pistons of the hydraulic part of the pump.

Housing of drive part is made detachable and consists of frame 1 and load-bearing cover processed together. The mutual position of the roof and the bed is fixed by special bushings. Drive part consists of transmission shaft 6 and shaft with connecting rods 9.

Transmission shaft is installed in cover of housing on spherical roller bearings. Bearings are enclosed in sleeves and closed from outside with covers.

Choosing a Rational Part Recovery Technology

The overhaul process is a set of measures to restore the operability of the equipment, carried out in a certain sequence and including:

Equipment acceptance for repair

Washing and cleaning operations

Disassembly of equipment into units, assemblies and parts

Inspection, sorting and repair of parts

Assembly of assemblies, assemblies and equipment in general

Run-in and test of equipment after assembly

Painting and delivery of equipment from repair

Washing and cleaning works.

Washing operations precede the stages of equipment development, defect and repair. The organization and technology of washing and cleaning works depend on the type of enterprise, the volume of production, the range of products to be repaired, the type of pollution. According to the conditions of production, universal or special washing areas are organized; external washing can be carried out in rooms or on a rack, washing is carried out manually or mechanically. Vortex and plunger pumps are used to obtain high pressure of washing jet.

Contaminants of the equipment are oil contaminants, lubricant residues, precipitates, abrasive and metal particles, paint residues, lacquer films resulting from the thermal oxidation of oil layers, rust.

Oil equipment operating in the open air is cleaned of sand, clay, drilling mud, oil, metal brushes and scrapers.

When preparing equipment for repair, cooling, power supply systems, oil tanks (crankcase, housings) are drained of cooling liquid, fuel, oil, washed with soda ash solutions, 5% hydrochloric acid or kerosene with addition of soda ash or sodium hydroxide. After washing, the systems in question are treated with steam.

As detergents for cleaning of the equipment of dirt, oil, oil, the remains of coverings use cold and hot (7090 °C) water, cold and hot alkaline solutions, solvents (gasoline, kerosene, acetone).

Preparing Part for Repair

The process of part repair by welding or surfacing consists of the following operations: preparation of parts by cleaning the surface from scale, rust and oil; preparation of part edges for welding seam; heating of the part to the required temperature during welding of satisfactorily and limited welded steels, and if the heat-treated part is welded, it should be tempered; welding or surfacing of a part; heat treatment of the built-up layer of the whole part; machining the part.

Recovery of worn parts by pressure is based on the principle of ductility of heated metal. Under the influence of a hammer or press, the part changes its geometric shape with an unchanged volume. There are several methods of pressure recovery:

squeezing under a press by means of a die and a punch; Note here that inner diameter of sleeve is reduced by wear and allowance for subsequent treatment. Note here that outer diameter is increased by welding or metallization;

distributing steel balls by pressing on the press through the inner hole of the bushing, which allows restoring the outer diameter of cylindrical hollow parts with an external working surface (for example, piston pins, bushings, etc.);

settling under the press when the height of the sleeve decreases but the wall thickness increases;

drawing (as opposed to planting) restores the length of the part by reducing its outer diameter.

When repairing shafts and axles, first:

welding and locksmithing works, since during their implementation deformations of the part are possible and purely treated surfaces can be damaged.

shafts and axles are straightened and pre-machined. Finishing of shaft working surfaces shall be performed last.

To ensure unchanged shape of the shaft and relieve internal stresses after straightening, thermal treatment is carried out, which consists in holding the shaft at a temperature of 400-500 ° C for 0.5-1 h. Significant deflections of the shafts are eliminated by hot straightening under a press, for which the bending point of the shaft is heated to 600 ° C in a burner or a gas burner flame.

Re-check the shaft for run-out and, if the bend is not completely eliminated, repeat the edit operation.

It should be remembered that the higher the degree of cleaning of the washing liquid from the broken rock particles, the more durable and reliable the operation of the pump units and parts.

Conclusion

In this course design, I considered the issues of maintenance and repair of the NBT600 drilling pump. Recommendations on the operation of the drilling pump, design information, occupational safety and safety during operation with the pump were also presented.

The repair of the transmission shaft of the drilling pump using the vibration surfacing method was considered. This method has a number of advantages: it allows you to restore the part in a short time, restoring the worn out part to the original state costs 2070% of the cost of the new part, reduces the cost of spare parts. The downside is the need for special equipment, which will lead to additional costs.

Questions were also considered to increase the overhaul period. The proposed methods are very effective and extend the period between repairs by several times.

List of used literature

1. Nikolich A.S. Piston drilling pumps, -M.: Nedra, 1973.

2. Verzilin O.I. Modern drilling pumps, -M.: Engineering, 1971.

3. Ilsky A.L., Mironov Yu. V., Chernobyl A.G. Calculations and design of drilling equipment. M.: Nedra 1985 g 457 s.

4. Bagramov R. A. Drilling machines and complexes. M.: Nedra 1988 g 432 s.

5. Composite - a catalog of oil and gas equipment and services. 1st edition in 3 volumes. M.: Energy. 274 pages.

6. Volkov A. S. Rig driver. VIEMS, MPR of Russia 2003

7. Severenchik N. A. Machines and equipment for drilling wells. M.: Nedra 1986 g 362 s.