| Even if you are a professional researching | | | | according to the specifications of the job in |
| information on metal bellows for technical | | | | hand. Often, a custom-made alloy can be |
| solutions and for installation of industrial | | | | designed to meet a job's requirements. |
| processes, it can sometimes be helpful (even | | | | |
| to the professional) to gain an overview of | | | | What specific applications are there for this |
| the product, what it can do, and just what | | | | technology? |
| situations it has been developed for. | | | | |
| | | | The central purpose for metal bellows is in |
| This guide will give you a few general | | | | fluid management. This, however, finds use in |
| pointers, and hopefully answer some of the | | | | a great many things. Expansion joint |
| questions you have. Of course, it is a guide | | | | solutions have been employed in industries |
| only; for detailed answers to any specific | | | | and technologies such as altitude sensors, |
| questions you have about projects you may | | | | piping for industrial coolant, the |
| have in mind, we recommend contacting an | | | | petrochemical industry, applications |
| expert in the field. | | | | involving steam, the nuclear power industry, |
| | | | medical technology, waste management, and |
| What does a metal bellows actually do? | | | | some automotive engines and pump systems. |
| | | | |
| A metal bellows is the term for an attachment | | | | What kind of tolerances can be built into it? |
| on piping typically designed to absorb and | | | | |
| mitigate the effects of directional change | | | | A metal bellows can be designed to cope with |
| and to minimize any issues arising from this | | | | a wide variety of different stresses and |
| such as clogging, pressure points on the | | | | pressures. The three main types of movement |
| bend, or expansion of the joint. | | | | are referred to as lateral, axial and |
| | | | angular. |
| It is a development of the basic expansion | | | | |
| joint idea used on installations like rail | | | | Lateral is a movement of the two ends of the |
| tracks to deal with the expansion and | | | | joint where those ends stay parallel to each |
| contraction of metal. The central concept to | | | | other. Axial is either the stretching or |
| keep in mind is that when subjected to force, | | | | flattening of the expansion joint along its |
| either heat or pressure, the metal bellows | | | | length. Angular movement is simply the |
| allows the expansion joint to bend rather | | | | curving round of the joint along its axis. At |
| than break. | | | | present, expansion joints can be designed to |
| | | | cope with any of these three specific stress |
| Why metal? | | | | types. |
| | | | |
| Metal expansion joints are, simply put, | | | | The one type of movement they cannot deal |
| stronger than the alternatives (plastic, | | | | with, however, is torsion, namely twisting |
| ceramics, etc). They are also easier to shape | | | | along the piece's length. This is best |
| (although metal bellows are relatively | | | | avoided by keeping the joint fastened in |
| intensive to create). | | | | place by external attachments, and taking |
| | | | care with the fastening when attaching it in |
| They are also more capable of coping with | | | | the first place. |
| extremes of temperature, as they themselves | | | | |
| can expand and contract without sustaining | | | | How much heat can a metal bellows withstand? |
| the weathering damage that hard plastic | | | | |
| would. There are rubber versions available, | | | | This varies greatly depending upon a variety |
| but their use is strictly limited, and in any | | | | of factors; the alloy chosen, whether or not |
| situations involving heat, for example, they | | | | any anti-corrosives are added, the design of |
| are impractical. | | | | the bellows itself, and whether it was welded |
| | | | or shaped. There are certain practical |
| Heat-tolerant bellows and expansion joints | | | | solutions and physical limits, but as long as |
| can be made from a variety of metal alloys, | | | | the heat is foreseen, joint solutions can |
| such as steel, titanium, and many others | | | | usually be found. |