We sell DuPont Uniseals in the UK through our Uniseal Shop site, a fantastic product that speaks for itself and takes the place of bulkhead tank connectors. The Uniseal Shop sells only two products, the DuPont Alcryn Uniseal and Flexseal EPDM rubber pipe connectors. The Uniseal is a pipe to tank seal, and by importing in bulk are able to keep the cost of Uniseals down to an affordable level in the UK and the EU. Stock sizes and quantities of Uniseals have been improved again and for 2022 every size up to 6" is available. So if you are looking for cheap Uniseals then you have come to the right place.
If you have a question you would like to ask about Uniseal pipe grommets then please do not hesitate to contact The Uniseal Shop. We have a Uniseal FAQ's page here which would probably answer your question.
Uniseal® Installation Tips
Some larger diameter pipes may require more force to insert them through a Uniseal®.
Ensure those pipes have a good chamfer on the end to be inserted.
Silicon pipe lubricant spray will also create less friction between the pipe and the Uniseal®.
Rocking the pipe gently from side to side when applying pressure will also aid insertion.
Use a block of wood to push the pipe through the Uniseal®.
Just prior to inserting the Uniseal® heat it by immersing in hot water for a minute.
For particularly stubborn installations use a ratchet strap around the vessel and the end of the pipe you would like to insert. Slowly ratchet the pipe through the Uniseal, tap the free end of the pipe with a dead blow hammer on a piece of wood.
There are a few hints and tips on the following videos which some people use to insert their Uniseals®.
YouTube Uniseal® Installation Videos
AEM Easy Drum 22 - Uniseal Mod 1
AEM Easy Drum 22 Uniseal Mod 2
When to use a Uniseal Vs a Bulkhead
How to Install a Uniseal Fitting
How to use Uniseals with thin walled pipe in the Aquaponic build
Aquaponic Uniseal installation How-to
UniSeal 1.5 inch hole in 5 Gallon Bucket
Uniseal® Holesaw sizes
Uniseal® Pipe and Holesaw Size Table
*1 Note 1 - Many websites show the required hole size for the 3/16 inch Uniseal as 10mm - it isn't and this would be realised by anybody who has fitted them. The actual Uniseal hole size for a 3/16" Uniseal required is 8 mm and can be created using a (sharp) drill bit.
*2 Note 2 - Uniseals U025 and U0312, Uniseals U050 and U075, Uniseals U275 and U300, Uniseals U400 and U400-SDR35 require the same sizes of holes. The difference is made up in the thickness of the Alcryn rubber. Uniseals with the same hole size are interchangeable, handy if you have the smaller size and want to increase the flow.
*3 Note 3 - Always measure the Outside Diameter (O.D.) of your pipe. This is the most important size to match into the Pipe O.D. hole size of the Uniseal to create your seal.
Water Flow Per Minute through associated pipework is a rough calculation and assumes gravity feed and low pressure systems.
Pipe I.D. - the Inside Diameter or bore of a pipe and how larger pipe size is denoted e.g. a 3 inch pipe has an inside diameter of 3 inches. Smaller pipes and tubes e.g. 6mm flexible PVC tube are denoted by their outside diameter (just to confuse things a little).
Pipe O.D. - The Outside Diameter of a pipe. This can vary dependant upon pipe type, construction, and manufacturer. An example of this is PVC/ABS pressure pipe which can have a thicker wall construction when the class number (pressure rating) increases. Makes sense when you think about it - higher pressure rating so a thicker wall in the pipe.
How do you determine what size of pipe you have and if it is suitable - Original Uniseals are ONLY made in Imperial sizes in the U.S.A. to suit their Schedule 40 pipe standards. The simplest thing to do is to measure accurately across the end of the pipe including the pipe wall thickness and match your Pipe O.D. to the table above. Uniseals will work perfectly on any pipe of the right O.D. size. Larger Uniseals have a tolerance of up to 2mm, however if your vessel is not pressurised you will get away with a little more. Some Uniseals fit into the same holesize and so are interchangeable e.g. U275 Uniseals can be directly replaced with U300 Uniseals.
Uniseals for Metric Pipe Sizes - Metric pipe sizes are denoted by the outside diameter (O.D.) of the pipe. An example of this is is a 75mm metric pipe (O.D.) which has an internal diameter (bore) of around 67.8mm. Some metric pipes have a near equivalence in size to the Imperial sized Uniseals so the 75mm metric pipe would fit into a Uniseal U275 for example. To check other metric sized pipes use the Pipe O.D. from the table above.
If you are using standard metric sized household pipes (popular in Hydroponics) the walls are thinner than pressure pipe. The sizes below will fit but check the Outside Diameter of your pipe. Do not assume that the name of the pipe is the O.D. size of the pipe.
The table below indicates which Uniseals work well with metric sized pipe O.D's.
Metric Uniseal® Pipe and Holesaw Size Table
*1 Note 1 - Many websites show the required hole size for the 3/16 inch Uniseal as 10mm - it isn't and this would be realised by anybody who has fitted them. The actual Uniseal hole size for a 3/16" Uniseal required is 8 mm and can be created using a (sharp) drill bit.
*2 Note 2 - Although our full range is not shown here Uniseals U025 and U0312, Uniseals U050 and U075, Uniseals U275 and U300, Uniseals U400 and U400-SDR35 require the same sizes of holes. The difference is made up in the thickness of the Alcryn rubber. Uniseals with the same hole size are interchangeable, handy if you have the smaller size and want to increase the flow.
Uniseals suited to Metric pipe sizes - Metric Uniseals
Standard Pipe Sizes
Pipes come in different sizes. The outside diameter of your pipe can be checked out from this website
www.pipestock.com/ who sell different classes (pressure rating) of pipe in different materials.
Don't get overly hung up on your pipe size unless you intend to pressurise your tank or vessel, Uniseals® have a little tolerance of around 2mm
on larger diameter pipes. The main criteria is that your pipe fits tightly through the Uniseal®.
Some Uniseals in situ. This is from a DIY blue barrel filter system on a fish pond.
Uniseals Image Gallery
Uniseals Holesaw Image Gallery
EU Uniseals Image Gallery
