Sewn Bellows are the most popular, most cost effective and are manufactured from a series of stamped annular square, rectangular, or pear shaped pieces sewn together. Specific 'split' Bellows are available with a zipper closure to eliminate machine disassembly and downtime. Sewn Bellows are offered in a variety of materials and material thickness with superior abrasive resistance to accommodate most applications. The choice of materials is influenced by the operating conditions, application and the type of construction.
Moulded Bellows are used where the most arduous applications are required. They can be manufactured in all types of Rubber Polymers and Polyurethanes. These Bellows are Air Tight and Water Tight and can be manufactured cost effectively even for low volume production. These Bellows are ideal for accommodating lateral movement or misalignment between fixing points. They are also ideally suited where aesthetics are a major factor in your equipment as they can be manufactured in any colour.
Vulcanised & Welded Bellows are manufactured specifically for demanding applications where seams inherent to a sewn bellow are not acceptable. Similar to the standard Sewn Bellow, sections are cut separately and then joined to form the completed cover; the Sealed Sections are joined by vulcanizing rather than sewing, resulting in a seamless cover. This technique results in many advantages including a neater appearance, longer life in abrasive environments, and a complete seal to withstand moderate internal or external pressures.
Full length zippers can be incorporated into the bellow, in cases where it will be difficult or too time consuming to dismantle the equipment for placement of the bellow. Zippers can be provided in metallic or poly-plastic type.
These type of inserts are used where the shape of the bellow needs to be maintained in working conditions. They consist of, internal steel rings or plastic disc inserts.
Often it is a prerequisite for the bellows not to build up an positive or negative pressure, in such cases air vents can be used. Sometimes moisture can also be an issue and therefore an air vent will allow for the moisture to evaporate from within the bellow.
For long working length bellows it is advisable to use tie straps, this allows the bellow to stretch evenly along the working length.
Can be used to eliminate other fastening methods for the cuff ends. In cases where the bellow is not likely to be over stretched, tie wires can be an effective method of securing the bellow and eliminate the use of hose clamps.
For long working length bellows, where the application is over an ACME or ball screw application, sagging of the bellow can sometimes cause some operational difficulties, where the bellow or even the ball screw may become damaged. For these instances we suggest the use of internal shaft guides or bush supports.
These supports are used externally and consist of small tabs with an eyelet, placed at the outer perimeter of the bellow.