Filtration Abbreviations Explained: L to X

Understanding all the terminology and abbreviations used in the filtration industry is no easy task. WE get asked to explain them all the time so we decided to create this blog series. Here is our second part – you can see Filtration Terminology A to I in the first part.

Today we follow on from before and help you understand the abbreviated terms form L to X.


LBS – Pounds
LR – Long Radius


M&F – Male and Female
MFG – Manufacturer
MI – Malleable Iron
MIN – Minimum


NC – Normally Closed
NO – Normally Open


OD – Outside Diameter


PE – Plain End
PSIA – Pounds per Square Inch Absolute
PSIG – Pounds per Square Inch Gauge


RB – Return Bend
RED – Reducer
RF – Raised Face
RTJ – Ring Type Joint (Also RJ)


SCH – Schedule
SCRD – Screwed
SF – Smooth Finish
SMLS – Seamless
SO – Slip-On
SOL – Sock-O-Let
SPEC – Specification
SR – Short Radius
SS – Stainless Steel
STD – Standard
STL – Steel
STM – Steam
SW – Socket-Weld
SWG – Swage


TE – Threaded End
TEMP – Temperature
TOC – Top of Concrete
TOG – Top of Grade
TOL – Thread -O-Let
TOS – Top of Steel
TYP – Typical


VERT – Vertical


W/ – With
WE – Weld End
WN – Weld Neck
WOL – Weld-O-Let
WT – Weight


XH – Extra Heavy (Also XS)
XXH – Double Extra Heavy (Also XXS)

That takes us up to X. If you know of any we have missed then please add them in the comments. You could even challenge us on one and see if we know it.

As a filter manufacturer we hope this has been some service to you. If you have any further question or have any filter problem then do not hesitate to  contact us by calling +44 (0)1634 724224 or send us an email to [email protected]


Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *