09/03/2019

Bobbins & Sandwiches

Let’s get back to basics and take a look at the most common mount

We’ve mentioned previously that the heart of what we do at AVMR comes down to the intimate understanding and deployment of 21 different product types. We’ll tailor the latest cutting-edge products to create the perfect anti-vibration solution for you. In the coming blogs we’d like to get back to basics and explain a few more of these 21 core elements.

Take the simple bobbin mount for example – a true staple of the anti-vibration art. It’s a round hunk of rubber (or composite material) bound on either side by a metal cap giving it a classic bobbin of thread in appearance. These caps may have male screw thread extensions. Alternatively they may be one male pin and one female thread, or simple two female threads and no pins. Wherever the mount is going there’s a mounting option for you.

Without the pins (and therefore looking less like a ‘bobbin’) you’ve essentially got a sandwich mount. The sandwich mount has a plate on opposing sides and each plate allows it to be bolted in place. It’s easy to see how the tools at our disposal can quickly be specced and deployed.

All of the mounts above work in one of two ways. The body of the mount will resist pressure and push back. So, when ‘sandwiched’ in a mount (be it bobbin shaped or otherwise) it will first bear the weight/pressure of what’s placed upon it, compressing a known amount with gravity playing its part and then coming to a point of resistance in a resting state. When vibration begins – the machine above is turned on, say – the mount compresses between its plates and quickly returns to this resting point. So one side of the mount moves with the machine, while the other – if we’ve got it right – will barely move at all. It can be argued that vibration can never really be completely removed, but our solutions can make it next to impossible to perceive.

And bobbin mounts can also work in ’shear’ as well as compression. That is to say it’s possible to design mounts that won’t just support and dampen on a vertical axis but will dampen a lateral, side-to-side moving object too. Machinery with large spinning parts hidden inside often generate significant surprising sideways motion that needs a versatile and clever mount. Accurately deployed bobbins effectively hold wayward machinery in a velvet grip as it tries to cause trouble – not so tight as vibration passes through to the ground or frame and not so loose as to allow the frequency of movement to build into danger levels. Get the balance right with the right products in the right places and you’ll ensure smooth and safe running.

And that’s at the core of what we do, though bobbins and sandwiches are just a small part of our war against vibration. To find out more, and how we can eliminate vibration for you, don’t hesitate to get in touch.