Heating cables
Description
Heating cables KGn.
Load carrying heating cables (KGn) designed for electric heating of oil wells equipped with electric centrifugal pump, injection wells and water wells, by lowering directly to the production tube, to the flow of produced fluid to prevent formation of solid components –paraffin hydrates.
Specifications
The cables KGn designed according GOST R 51978-2002 «Load carrying geophysical armoured cables» and TU 3585-002-24118545-2004, certified and qualified for use by Federal Authority for ecological, technological and nuclear control and protected by patent of Russian Federation ¹35823.
At the moment, the cables KGn are the most required cables.
Maincharacteristics of heating cables KGn are indicated in tables.
Mechanical characteristics of heating cables KGn
Type of cable |
Breaking load, not less |
Recommended length |
Maximal operating temperature |
Outer diameter of cable |
Weight 1 km in air |
Weight 1km in water |
|
55 |
1100-1300 |
100 |
27 |
1220 |
713 |
|
50 |
900-1100 |
100 |
25 |
1056 |
525 |
|
50 |
700-900 |
90 |
27 |
856 |
325 |
|
50 |
800-1000 |
90 |
27 |
865 |
334 |
Electric characteristics of heating cables KGn
Type |
Number and section of conductors, n x mm2 |
Number of groups |
Resistance of single conductor, Ohm/km |
Resistance of insulation, MÎhm*km |
Maximal operating current (dc/ac), À |
Type of supply voltage |
|
14 x 1,5 |
7+7 |
9,57 |
20 000 |
140/- |
direct |
|
12 x 1,5 |
6+6 |
12,4 |
20 000 |
130/- |
direct |
|
12 x 2,0 |
4+2+2+4 |
15,8 |
20 000 |
110/73 |
direct |
|
14 x 2,0 |
7+7 |
15,8 |
20 000 |
120/- |
direct |
Heating cables KnP
Since 2004, ÎÎÎ «Pskovgeokabel» producedheating cablesforwellsequipped with rod or depth pumps. Heating cables, flat shaped, installed outside production tube similar to the power cable for oil submersible pumps.
Despite less effective heat transfer of the cable installed this way, available operational parameters showed that these systems are fully suitable for prevention of paraffin formation in wells with rod or depth pumps. Experience of operation of the installations in a periodical mode is available, i.e. heating is on during 24 hours, then several days is pause, this complies to cyclic washing of wells with hot oil but use of hot oil can be excluded.
In general, periodical mode is the most favorable from economical point of view and for the reason to decrease of power consumption. However, despite the fact that supplied equipment allows to choose this mode, possibility and parameters of periodical heating are selected by a technical service of oil productive companies because in this case the most important factor is a composition of well fluid, a percentage of paraffin content, and rate of its formation etc.
Mechanical characteristics of heating cables KnP
¹ |
Type |
Minimal length of supply, m |
Dimensions, mm |
Weight 1 km, kg |
Number of groups of conductors |
Nominal power density, W/m |
1 |
|
850 |
10,5õ26 |
1041 |
2 |
50 |
2 |
|
1000 |
10,5õ34 |
1070 |
2 |
60 |
3 |
|
1000 |
10,5õ34 |
1084 |
2 |
55 |
Electrical characteristics of heating cables ÊnP
¹ |
Type |
Number and section of heating elements, Nõmm |
Voltage |
Resistance of single conductor of heating element, Îhm/km |
Resistance of insulation, ÌÎhì*km |
Maximal current, À |
1 |
|
6õ2,0 |
Direct |
8,7 |
10 000 |
95 |
2 |
|
8õ2,0 |
Direct |
8,7 |
10 000 |
120 |
3 |
|
8õ3,1 |
Direct |
9,1 |
10 000 |
120 |
HeatingcablestypeKn
Atthepresentmoment, specialistsofÎÎÎ “Pskovgeokabel” have designed and now preparing production of a heating cable for hollow steel rods of well pumps. The cable has round shape and diameter 14-16 mm and installed inside of these steel rods. The design includes segmental heating conductors with double insulating sheath, central load carrying core made of glass plastic bar, armouring tape, and outer polymer sheath.
Main parameters of cable Kn
Electrical: Resistance of current conductor, not more Resistance of insulation, not less Mechanical: Breaking load, not less Calculated weight of cable Maximal operating temperature |
2,5 Îhm/km 20000 ÌÎhm*km 10 N 293 kg/km 100 îÑ |
Descriptionofthetechnologyandwaysofheatingwouldbenotcomplete without examining economic aspects of using the proposed equipment. The most difficult problems of the potential customers are connected with two main concerns:
1. Who will perform lowering and rising operations and how?
2. Where obtain so much power?
Concerning consumed electric power and consequently the main part of costs for operation of electric heating, indicated power figures look big only for the first sight. For example, for a well with flow rate 20 t/day of oil and heating installation 50 kW, additional cost for power per ton consists 60 kW or 2-3 dollars and it would be around 1% of cost of product (i.e. oil). Performing further economic calculations on this stage has no sense because each of our customers has special departments for this purpose, and a result of use of electric heating will appear after some time of operation of the installations. However, on first stage of analyzing of economics it is necessary to account the following factors:
- Indicated figures of costs for unit of products (around 1%) significantly lower than average in the industry.
- Increase in power consumption will definitely cause decrease of costs for repairs including mechanical scrapers, processing with hot oil, increase of time between repairs, etc.
- Use of electric heating always followed by increase of flow rate (in average 10-15%, in some cases up to 200%) and decrease of watering.
As the last argument in favor of installation of electrical heating is possible to state that all our customers have a payback period for the equipment (control station, cable, auxiliaries) not over 8 month with account that the warranty period is 12 month and average life time till breakdown 2,5 years.