Tubing Design

Confidential © 2009 Infotech Enterprises Limited

Contents

Introduction to Tubing design

Definition of Pipe & Tube

Tube, connectors & Fittings

Preparation of tube

Machine for mounting cutting ring

Fittings

Tube bending machine & tools

Clamps

Std. Tube diameters and its bendradius

Design considerations

Creation of Tube

Confidential © 2009 Infotech Enterprises Limited 3


Definition of Pipe & Tube

Pipe and tube are hollow cylinders

Pipe:

Where ID is constant. Normally used to convey gases

or fluids so the internal cross-sectional area is

important .

Tube:

Where OD is constant. Frequently used in

structures. A tube is often made to custom sizes

and may often have more specific sizes and

tolerances than pipe


Std. Tube diameter and bend radius

Standard diameter of tubes and Bend Radius used in LOC.

Tube Diameter

(mm) Bend Radius

10 20

12 24

18 36

20 40

28 56

35 70

Tube Diameter (inches) Bend Radius

1½ 76

1¼ 80

3/4 45

1/2 40

3/8 20


Tubes, Connectors & Clamps

24° cone connectors

37° flared connectors

If the tubing is inch-based, JIC/37 degree flare types, or O-ring face seal types. If the tubing is metric, 24 degree compression-type.


Preparation of Tube-1

Cross sectional view

Method-1

Method-2

1. Connector2. Nut3. Compression Ring / Cutting Ring4. Tube

Before After


Preperation of Tube-2


Preperation of Tube-3


Machine for mounting cutting ring


Fittings-1

Parts in “T” fitting

Parts in Bulk Head

Assembled Bulkhead


Fittings-2


Fittings-3

Swivel Elbow Bulkhead Straight

Tee


Fittings-4

Bulkhead Elbow


Fittings-5


Tube bending machine & tools-1


Tooll for Tube bendngeg: 18 OD Tube tool Bending Tool in position Guide for bending Tube

Tube bending machine & tools-2


Clamps- DIN 3015

Quick Release Swivel Bolt Clamp

HRL, HRS, HRZ, HREL, & HRES Series

more info


Design considerations-1

Contd…


Design consideration-2

Check the maximum available lengths of a tube in the market before starting design (std. 6-9 meters)

As for as possible, the pipe lines are laid straight and narrow bends are eliminated and smooth bends are given wherever possible to enable un-interrupted free flow of air.

While designing tube, see that there are no water backs.

Try to avoid Z / S - type of layout for the tubes

Wherever a joint is provided, the supports are given on both sides, near to the joint to avoid the loosening of the joint by vibration and thereby leakage.

Always additional 30 mm per side to the tube. So, that this will give enough support length for the bending machine.

As far as possible, the main equipments and pipes are connected with adapters fitted on the equipment . This will ease the removal of the equipment for maintenance as well life of threads on the equipments can be increased.

While modelling tube see that first point is at bigger side of length.

Flexible hoses are used to connect between fixed and moveable devices e.g. Between Air compressed cubicles and Under frame connections

Minimum distance between bends can be defined as the straight length along the CL (centre line) between

the tangents of the adjacent radii.

Minimum distance to the first bend along the CL is required to provide clearance for the machine used to

swage the Stainless Steel pipe fitting bite ring to the pipe

Confidential © 2009 Infotech Enterprises Limited 21

1. Minimum Length of the Straight Tube H= 2 x Nut Length (L)

2. Minimum Length L3 of the Straight Tube ends before bend.

H

LL3

Design consideration-3

1

2


Thank you

Documents

Tubing Design