Annflex Expansion Bellows are Designed based on Various Engineering Codes. EJMA – latest,  Ad-Merc Blatt,  ASME section VIII appendix B, TEMA, IBR coded.  Fully Computerised CAD/CAM programme puts each design to adequacy check.


Product & Range

Convoluted thin sheet multiply metallic bellows circular – 2″ (50NB) up to 300″ (7500 NB) & No size and shape bar for other profiles.

Design temperature (-) 196°C to 2500°C .

Design Pressure – From  Full vacuum to 150 Kg/cm^2 (g).

Annflex Bellows are made on…

  • The technique is a hydraulically operated expanding mandrill process with utmost care in minimizing the bellow’s thinning as low as 3%.
  • Electronically controlled TIG welding ensures smooth weldments at each joints.

Simple axial expansion bellow

Guided or un guided with weldable pipe niples for axial deflections on a straight run of piping.

Double universal expansion bellow

A pair of simple axial bellows at a specified distance functions as a universal movement absorber. This bellow is generally supplied with limit rods as guides. Another type is Tied lateral where tie rods at both ends are bolted using spherical nut and washer arrangement. This assembly is rigid axially but deflects in any lateral plane.

Hinged expansion bellows

A single axial bellow is restricted using hinges & pins arrangement for a change in direction of piping at an angle.

Gimbal expansion bellows

A single axial bellow is put to multi directional angular movement using a gimbal ring around the bellows.

Pressure balanced expansion bellow with elbow

A pair of single axial bellows tied and blind flanged at one end and an elbow to change the pipe direction. This design is for a constant volume arrangement and eliminates flow turbulence and pressure thrust.

Inline pressure balanced expansion bellows

A constant volume arrangement in a high pressure turbulent piping system to avoid pressure thrust and flow turbulence. This is obtained by two balancing bellows whose total cross sectional area is equal to that of In-line bellow. This bellow is widely used in viscous liquid systems having turbulence.


Product:Metallic Expansion Bellows, Joints, Kompensators, Corrugated hoses, PTFE Bellows
Type:Circular, Rectangular & Oval
Sizes:i) Circular – 2″ (50 NB) To 300″ (7500 NB)
ii) Rectangular & Oval; No Limit for Shape and Size
Pressure Rating:From vaccum 1×10^-6 CC/Sec to high pressure upto 100 KG/CM^2(g)
Temperature:From – 196 Deg.C To 2000 Deg.C
Average Fatigue:3000 Cycles (Approx 6 Year Life)
Movement Range:Appx. *50% Expansion / Compn. & Appx. 5% Lateral (*reference of convoluted length)
Material Handled:ASTM A 240 TP 304, 316, 321, 309S, 310, 310S and its Low Carbon Derivatives, ASTM SB-Inconel 600, 625, Incoloy 800HT, 825, Ni 201, Avesta-253Ma, Copper etc.