Duct Fitting and Accessories in Optical Network

Duct Fitting and Accessories in Optical Network: It seems to me that duct fitting and accessories play an important role in optical network construction. During optical network construction, if there is a slight mistake in duct fittings or accessories, then a lot of problems are encountered. So during optical network construction, site engineers need to take care of duct fittings and accessories in particular.

I will try to give complete information about duct fittings and accessories in this article. This article will covers the minimum standards and requirements for the construction, properties, testing and packing of PVC duct fittings and accessories. Tools and accessories are important in optical network construction because using tools and accessories is the right and the only way to work in the field.

Duct tools and accessories

Duct Fitting and Accessories in Optical Network

Duct fittings and accessories specification

The PVC duct fittings and accessories described in this specification are as follows: 

➥Bend ( 90 ° - 2000 mm radius )
➥Bend ( 45 ° - 2000 mm radius )
➥Bend ( 90 ° - 1000 mm radius )
➥Bend ( 45 ° - 1000 mm radius )
➥Double Bell Coupling (0°)
➥Double Bell Coupling (5°)
➥Sleeve

➤The Bend ( 90 ° - 2000 mm radius ) and Bend ( 90 ° - 1000 mm radius ) is used to provide a 90 degree directional change to the duct run. 

➤The Bend (45 ° - 2000 mm radius) and (45 ° - 1000 mm radius) is used to provide a 45 ° directional change to the duct run.

➤The bends shall be provided with bell and spigot ends; and they shall have a 150 mm straight extension on the ends, the spigot end shall be chamfered to produce a l5° beveled edge along the outer circumference. The length of the straight part of the bell shall be at least 80 mm.

➤The 90° bends shall bear a mark where they can be cut into two equivalent 45 ° bends.

➤The Double Bell Coupling (0°) is used to connect two spigot ended ducts straight through.

➤The Double Bell Coupling (5 °) is used to connect two spigot ended ducts and also to provide a 5 ° directional change to the duct run.

➤The Double Bell Couplings shall be at least 200 mm total length with an inner ridge in the middle to act as a stopper for the duct.

➤The joining of two ducts with these couplings shall provide a water tight joint.

➤The Sleeve is used to provide a repair sleeve over a PVC duct. It can also be used to provide a strong straight coupling between two straight (spigot) ends of ducts.

➤The Sleeve is a straight PVC tube at least 3000 mm of length with an inner diameter to fit over the outer diameter of the PVC duct.

➤All PVC duct fittings shall be produced to fit the PVC duct.

Duct Accessories Design

Duct Accessories

Duct Plug

Duct Plug: The duct plug shall be a mechanical device used to seal the duct from the entry of water. It shall be able to be installed and removed by simple hand tools.The duct plugs shall be designed so as to accommodate the tolerances of manufacture of the PVC duct types into which they will be installed, The dimensions are used according to size of duct details.

The method of installation shall not be hazardous to either personnel or adjacent cables. It shall be possible to remove any plug without damage to either duct or cable. An 'eye' shall be provided on the inner side of the plug, to which a draw cord can be attached.

Sub-Duct Anchorage : The sub-duct anchorage shall anchor sub-ducts in the ends of the PVC ducts. It shall be possible to secure four sub-ducts in the anchorage.

The anchorage shall form an effective water tight seal to sub-ducts and the PVC duct in which the anchorage shall be installed.The anchorage shall be removable without major effort to permit the sub-duct to be reinstalled.The anchorage shall be easily installed using standard tools.

Duct Sealant : The duct sealant is used to seal ducts which have cables installed. The duct sealant shall be capable of sealing more than one cable per duct. The installation shall require the minimum of preparation of duct and cable to produce the sealing requirement.

The sealant shall be a suitable putty and be easily removable to allow the installation of additional cables.The installed sealant shall effectively seal the duct from the entry of water.

Material Properties of Duct fittings and accessories

All materials used in the PVC duct fitting shall be non-toxic and dermatological safe. The test results are intended to assure the Telecom industry that products have been designed to provide fault free service for the required life of the PVC duct fitting.

Tenderers are required to ensure that supplied PVC duct fitting complies fully with the type approval requirements as per Telecom industry.

Duct Couplers 

Duct couplers used to connect and repair the duct.Duct coupler seal off moisture, dust, air, water, dirt etc.If the duct coupling is not fitted properly, it may cause leakage in the duct which will make failure the DIT process. Duct coupler generally made-up of plastic or polymer. Duct coupler is economical, reusable, fast and easy to install. 

There are five types of duct couplers that can be used to fit two ducts together.

1.Simple Coupler

2.Push-fit Coupler

3.End Coupler

4.Reducer Coupler

5.Coupler for Special Ducts.

Now I will tell you about all these couplers here only through the picture, which will help you to understand.

Duct Fitting Accessories

Duct Couplers

Split Bush

Duct Sealing

Split Bush

To seal entry port of main duct having one main Optical fiber cable and one microduct or as required.

Simple operation: Easy to install and easy to remove.
Option to have 1, 2 or 3 entry ports of dia upto 15 mm.

Duct Tools

Some tools are also used during duct installation in optical networks, such as De-coilers, Pulling devices, Cutters, C-Spanner, Chamfering tool/ Deburring tool, whose picture I am applying which will facilitate you to understand.

Duct tools used during installation

Duct tools

You Can also READ-

1. What is the use of FRE Duct in Optical Network
2. Laying the optical drop cable in FTTH
3. Duct and optical fiber laying technique