Single Arch Rubber Bellow

What is Rubber Bellow ?

Rubber Expansion Bellows are designed to take care of misalignment, neutralize movement factor and minimize noise and vibration in pipelines and Ducts. They reasonably neutralize the sound and vibration generated from other equipment/machinery in the plant items in the same service building. This Rubber bellows can also be used for many other applications like water, oils, chemicals, gases and in the food industry depending upon the grade of rubber employed. Rubber bellows are available from 25mm to 1200 mm n.b.(1″ to 48”n.b.) and generally supplied complete with electro-plated carbon steel or Mild Steel.

Rubber expansion joints are known for its superior performance. These rubber expansion joints is used in a variety of curing system and superior overall performance. Compared with the conventional curing system, this expansion joint is the best in no reversion phenomenon, curing uniformity, good heat resistance, low compression deformation.

Composition and Reinforcement of Rubber Bellows

RUBBER BELLOWS

A rubber bellow is manufactured from independent rubber layers and reinforcements that are vulcanized together after being moulded or formed. With over 35 rubber elastomers available and the ability to further modify properties by compounding it can be challenging for non-specialists to select the most appropriate rubber polymer for their requirements. Our experts may assist our customers with material selection for a proper performance and to reduce the risk of failure.

FABRIC REINFORCEMENTS

Standard constructions normally utilize high quality synthetic fabric like Nylon, Polyester. Fabric plies are impregnated with rubber or synthetic compounds to permit flexibility between the fabric plies.

METAL REINFORCEMENTS

Wire or solid steel strings are imbedded in the carcass and are used as strengthening members of the joint.

FLANGES

Mild steel as standard. Also available in zinc plated or hot dip galvanized carbon steel, stainless steel, duplex, etc. Flanges drilled to

EN, ANSI, JIS, AWWA standards or any specific dimension.

TIE RODS

Rubber expansion joints under pressure (operating or test conditions) develop an axial reaction force across the effective bellows cross section area which acts on adjacent plain and ﬁxed bearings. This bearing stress in the pipe system is drastically reduced by using lateral and/or angular expansion joints with tie rods. Only the adjustment forces and moments from the lateral or angular movement are introduced into the pipe system and absorbed by lightweight ﬁxed points.

TENSION RODS

This type of tensioning is used for lateral expansion joints or can be used to limit the element length on universal expansion joints. Threaded rods are placed symmetrically around the circumference and supported either with rubber bushes or with spherical washers, conical washers and nuts. Using rubber bushes creates a noise absorbing connection to the ﬂange; this is done up to a Nominal diameter of maximum DN 300. For absorbing excess pressure (internal pressure), only external tensioning is required and additional internal tensioning for negative pressure (vacuum). All metal components such as threaded rod, nut, spherical washer and conical washer are galvanized as a standard. Versions mode from corrosion resistant materials or with hot galvanizing are available on customers request.

VACCUM SUPPORT RINGS

Rubber bellows resist small to medium levels of negative pressure, depending on Nominal diameter, design and application. For higher levels of negative pressure or full vacuum it is usually necessary to install vacuum support rings. These support the inner surface of the bellows curve and are made of stainless steel as a standard. Different designs are available, from a single open support ring and support rings with lock to a ring which is vulcanized into the bellows during production. The latter design is only available for type 2 rubber expansion joints. As a rule, the permitted movement absorption is reduced by approx. 50 % Precise data for vacuum stability can be found in the tables or supplied on request.