Mechanical seal identification

Comments 0 by in standard
September 10, 2014

Here at Industrial Pumps & Motors Ltd ( IPM ), we are quite often asked the question, do we supply pump seals ? ( also more commonly known as mechanical seals ), and the simple answer to this question is “yes we do”. We are then asked for a price and availability for either a 12mm seal, or an 18mm seal, or a 50mm seal, or whatever the shaft size may be. Wouldn’t that be easy. Unfortunately this is not enough information. There are many different types, sizes and material variants fitted to pumps, and it is most important to get this right before we do anything.

Most times if our customer has a pump make and model, we are able to cross reference the seal type by using our huge online data base and seal catalogues. Other times, through experience, we just know which seal fits in which pump. However, over time pump data plates can either corrode away, become difficult to read or just go missing completely. When this happens, all it not lost, as there are ways of identifying exactly which seal you have, and then determine if it’s the right seal for the job.

With the advent of the internet, digital photography and email, the job becomes much easier than it used to be.

Firstly, if the seal has not been removed from the pump, then take one or two photographs of pump and email it over to us. If we recognise the pump make and type, we may then ask for a few simple measurements just to enable us to establish the model size. Also, most importantly we will ask what media is being pumped and at what temperature, just in case the standard seal has been changed for one more suited.

If the seal has been removed, then a photograph of the pump will still be useful, but a photograph of the seal will be more helpful.

mechanical seal from a mixer or stirrer gearbox

mechanical seal from a mixer or stirrer gearbox

Above we have a photograph of a seal taken from a very old imperial gearbox on a stirrer. The customer is based in Gloucestershire and has branches in Oxfordshire, Cambridgeshire and Staffordshire, and each branch has the same type of stirrer on site.

Please click on the picture and you will clearly see where I have written information about the dimensions and materials. This is tells us everything we need to know about the seal.

This particular seal is fitted with a locking collar which is grub screwed on to the shaft and sets the spring tension, so it is most important that the collar diameter is known so that we can make sure the spring will push over giving a nice tight fit.

So, after cross referencing the dimensions, we established the seal type to be either a Vulcan type 97 or a Roten type ROF, and the picture below shows the old seal on the left next to the brand new one we supplied on the right.

2014-09-09 16.18.18

If you look at the new seal on the right, you can see that the spring thickness is greater than the old one, and the new spring length is also shorter than the old one. Arguably the seal we have supplied is of a better quality than the original, hence the more heavy duty overall appearance, but if you were to compress both seals they would both go down to the correct working length.

Please do not hesitate to contact us should you require a seal identification or any other queries regarding pumps, seals or electric motors. Either email us directly, call us, or use the contact form if you prefer, and hopefully we will be able to help.