Branch Fittings

Branch connection fittings, commonly referred to as O'lets allow a smaller "branch" pipe to be extended from a larger (or same sized) pipe run.   Branch fittings are preferred whenever a non-reinforced miter-branch is satisfactory to withstand the internal pressure requirements.

There are three common styles of O-lets: weldolet, threadolet, and sockolet.  They are given their name by the manner in which they connect to the branch pipe.  The weldolet has a buttweld connection, the threadolet has a threaded connection, and the sockolet has a socket weld connection.  In addition to these three common styles, there are also elbolets, nippolets, laterolets, and MSI can offer these as well. The most important branch connections are:


Branch Fittings

WELDOLET is the most general branch connection type manufactured and supplied all over the world. Weldolet branch is made by soldering the item to the opening of the run pipe. The ends of a weldolet are bevelled to ease the welding procedure, and thus weldolets are appropriate to the family of butt weld fittings. Weldolets curtail the stress absorption on the branched connection and offer an essential reinforcement. Weldolets are offered in multiple material grades and dimensions.


Branch Fittings

SOCKOLET are quite comparable to weldolets, with the difference the weldolet and the sockolet both have a run end and a branch end. The run end connects to the larger diameter pipe, and the branch end connects to the smaller diameter pipe. The connection to the run pipe is a fillet weld for both the weldolet and the sockolet. They differ, however, at the connection to the branch pipe. The weldolet has a bevelled end to butt weld to the branch pipe (which will also have a bevelled end), whereas the sockolet has a socket into which a plain end branch pipe is inserted, then fillet welded together


Branch Fittings

THREDOLET are parallel to weldolets, but the branched pipe is bolted inside the olet (which is normally NPT threaded) and no welding action is consequently essential. The bore of a sockolet matches the bore of the branched pipe. Thredolets are categorized as threaded fittings, and are manufactured and available in 2 different classes as mentioned below.

  • THRADOLETS (3000 #): Avail best quality Threadolets (3000 #), which have pressure grade of 3000LBSCH40, SCH80, STD, XS, 6000LBSCH160, XXS etc. The material used are carbon steel of A182 A105 and stainless steel of A182 F304, A182 F304L, A182 F316, A182 F316L, A182 F321 etc. The sizes of Threadolets (3000 #) we offer are from 1/8" to 20", thus meeting diverse needs. We also cater to custom configuration needs of clients.
  • THREADOLETS (6000 #): We supply and export Threadolets (6000 #) in carbon steel of A182 A105 and in stainless steel of A182 F304, A182 F304L, A182 F316, A182 F316L, A182 F321 etc. These are available in sizes ranging from 1/8" ~ 20". The wide variety offered fulfills the different industrial demand and offers superb performance for long span of time. Durable in quality, our threadolets are preferred by many global buyers for quality & cost efficiency.

About Us

MSI Supply is a Houston, TX based full-line distributor of pipe, valves, fittings, flanges, stud bolts, gaskets, and fasteners, serving price-conscious customers who desire quick deliveries and consolidation of their material needs. With a large inventory of carbon and stainless pipe, cast and forged steel valves, tubing, and the thousands of fittings and fasteners required to put it all together, MSI can meet the needs of virtually any piping, fastener, or instrumentation project.