Slip-On Flanges

Slip-On flanges or SO flanges are commonly lower in price than weld-neck flanges, and to this effect are a popular choice for our customers.


It is welded both inside and out to provide suffcient strength and prevent leakage.

Slip-On Pipe Flanges. As made obvious by their name, these pipe flanges slip over the pipe. They're manufactured with an inside diameter that is slightly bigger than the pipe's outside diameter. These attachments are connected to the pipe via fillet weld at the top and bottom of the flange.

However, customers should bear in mind that this initial cost saving may be diminished by the additional cost of the two fillet welds required for proper installation. Moreover, weld-neck flanges have a higher life expentancy than slip-on flanges under duress.

Slip-on flanges are all bored slightly larger than the O.D. of the pipe. They are preferred over welding neck flanges bu many users due to their lower intial cost, but final intallation cost is probably not much less than that of the welding neck flange because of the additional welding involved.

Weldneck and Slip-On Orifice Runs

Advantages of slip on flanges:

A combination of flange and elbow or flange and tee is not possible, because named fittings have not a straight end, that complete slid in the Slip On flange.



Standards, Dimensions & Weight of Slip on flanges

The Slip-on flange has a low hub because the pipe slips into the flange prior to welding.


1. Slip On flange 2. Filled weld outside 3. Filled weld inside 4. Pipe
Material of Slip-on flange:

Slip on pipe flanges in stock include AWWA slip on pipe flanges, ANSI slip on pipe flanges, Pressure Vessel slip on pipe flanges and slip on pipe flanges that match the OD and drilling of ASME flanges.

Packing: plywood case and plywood pallet

").css({position:o.cssfixedsupport?"fixed":"absolute",bottom:o.controlattrs.offsety,right:o.controlattrs.offsetx,opacity:0,cursor:"pointer"}).attr({title:"Scroll to Top"}).click(function(){return o.scrollup(),!1}).appendTo("body"),document.all&&!window.XMLHttpRequest&&""!=o.$control.text()&&o.$control.css({width:o.$control.width()}),o.togglecontrol(),t('a[href="'+o.anchorkeyword+'"]').click(function(){return o.scrollup(),!1}),t(window).bind("scroll resize",function(t){o.togglecontrol()})})}};scrolltotop.init();