• Contacts
• Products
• About

• cables and wires
• welding equipment
• precision molding
• logging cables and equipment
• • Gispribor-M
  • A new product
  • Pskovgeokabel Ltd.
• Certificates

This comparatively new group is reproduced by armored items containing cored (hollow) liquid or pressure-operated channel - polymeric or metal tube or small-diameter tube. Standard view and physical form of tube are given in picture 4.6.1.

Picture 4.6.1. Logging Tube

Basic elements of construction:

1. - cover of inner shell of tube.
2. - steel tape
3, 4 - armor and logging elements out of high-carbon steel wire.
5. - outer shell.

Constructional modification of tube reminds of widely applied hydraulic hoses of high pressure, though the tube offered possesses unlimited factory length and has logging properties.

Inner tube or small-diameter tube is manufactured from polymeric material using extrusion technique. Wires of armor put onto polymeric tube have two differently directed layers, and space between two adjacent wires comprises from 1 to 1,4 diameters of wire (The Coefficient of Filling the Layer look in p.2.5.3.) that is 0,35 - 0,5. Wires have preformation which means they are given the form of helix at the process of laying. Parameters of concertina wire of each layer (lead, height) and appropriate diameter and lead of their laying into an end item are connected thus that wires could provide mechanical resistance of tube and breaking strength.

Construction of tubes is covered by the patent of the RF #44782 "Flexural expanded tube".

By the moment tests are completed at the enterprise and such types of items are produced with inner diameter from 5 (capillary or permeation small-diameter tube) to 20 mm (3/4"). Basic parameters of armored tubes are given in Table 4.6.1.

Main Properties of Logging Tubes

Table 4.6.1

*Weight in air for two cases:

• cored (hollow) tube
• tube filled with water.

** Weight in water is given for tube filled with water.

Application of tubes offered here is possible as an alternative to a column of flexural steel tubes or NKT for underground repairs of wells with use of the so-called coil tubing technology. It is clear of course that armored polymeric cable can not replace completely columns of flexural tubes which are applied at the moment for instance for hydraulic fracturing of formation but that is not the goal of the manufacturer. However, there are plenty of operations which do not necessarily demand complicated coil-tubing devices.

The variants of tubes offered here are rather mini coil-tubing which can be applied in following operations: flushing of bottomhole, bottomhole acidizing, swabbing with the help of gas-lift unit, liquidation of paraffine, hydrated or sand plug, feeding of well with chemicals (rust inhibitors, dissolvants, etc.), technologies of well stimulation with the use of liquid flammable oxidating, etc.

The main advantage of these tubes is the fact that technologies offered here can be implemented with the use of less expensive devices, for instance with the help of geophysical lifter, while round-trip operations will be similar to the work with standard geophysical device.

Experience of applying the armored cables of similar construction makes it possible to assume the possibility of using polymeric tubes for works in the bottomhole through annulus with settled lift equipment.

At the moment the enterprise is working at creation of polymeric logging tube with electrical conductors - that is the so-called flexible drill string. Construction of such flexible drill string is given in picture 4.6.2.

Additional conductors are put lengthwise on outer jacket of tube 5, united in a joint jacket.

The advantage of such construction is the fact that together with hydraulic channel there are also isolated conductors which can be applied for power supply of hole equipment or transferring signals.

Picture 4.6.2. Construction of flexible drill string.