Types of Metal expansion joints.

Axial expansion joint with weld ends is the simplest type of the expansion
joints, it consists of a single bellow element and weld ends on both sides.
Universal expansion joint with weld ends is the second simplest type of the
expansion joints, it consists of an universal bellow element , weld ends
on both sides and a center spool pipe. In the application of axial movement
and angular movement, the universal structure type will provide more flexibility.
Axial expansion joint with flanges is a type of expansion joint that the bellow
element is fitted with flanges on both sides. Flanges can be fabricated
according to DIN standard, ANSI standard, JIS standard and GB standard.
Special standards can be customized made as per customer’s requirement.
Universal expansion joint with flanges compared with Universal weld end
type Expansion Joint, the Universal flanged type are fitted with flanges on both sides and the connection of two bellow elements also a center spool pipe
which provides more flexibility with respect to the application of axial, and
angular movement.
Tied single expansion joints with flangesa combination of the single bellow
element with tie rods, the tie rods are designed to absorb pressure loads and other extraneous force like dead weight. The tie rods are attached to the pipe
or flange with lugs that carry the pressure thrust of the system, eliminating the need for main anchors.
Tied universal expansion joints with flanges are similar with Universal flange type expansion joints, the pressure thrust which caused by lateral offset and
angular movement will be compensated by utilizing the tie rods.
Single externally pressurized expansion joints it consist a single bellow
element only. Line pressure will act externally on the bellow element by use of
the pressure chamber. This allows more convolutions to be used to control
axial movement, and alleviate concerns of bellows instability.
Double externally pressurized expansion joints compared with Externally
Pressurized Single, it consist dual bellow elements. If continuing medium
exists, the dual and added convolutions will effective.
Hinged expansion joint with flanges angular movement is limited to one
plane. In high pressure piping systems, two or three Hinged Bellows
Assemblies may be used to absorb large amounts of expansion.
Double hinged expansion joint with weld ends are formed of two bellows
connected with central pipe. Each bellows is designed to allow angular
displacement in one plane only what is result of tie elements (hinge plates
and pins) and as set expansion joint compensates lateral movement.
Gimbal expansion joint with flanges allow angular movement in any plane,
while absorbing pressure thrust and torsional twist. In complex piping system,
such as “L” or ”Z” type piping, gimbal bellows assemblies always be used in
pairs with a single hinged unit, has the advantage of absorbing movements in multi-planer piping systems.