Emerson TESCOM - Page 18

18
TESCOM™ Safety, Installation, Operations & Service Manual
Content
December 2020
Installation Manual
TR000238ENUS-01_12-20
The following steps outline the disassembly of back pressure regulators for maintenance
and repair:
1. Clamptheregulatorinavisebytheatsonthebottomand/orsideoftheregulator
body.
2. Turn control knob and/or spring adjustment mechanism counterclockwise to insure
removal of all spring force on the piston.
NOTE: (Dome loaded regulators): All pressurized gas or liquid must be vented from
dome before disassembly.
3. Remove upper portion of regulator (bonnet and/or dome). Some models require the
handknoband/ormountingbrackettoberemovedrst.
NOTE: Upper portion of regulator may also include spring button, load spring, back-up
plate, and piston sensor, etc. Review correct drawing to ensure that all parts have been
disassembled.
4. The seat parts can now be removed from the regulator body by turning the seat
retainer counter clockwise until it is free of the regulator body.
5. To disassemble sensor and valve assembly and/or valve, clamp the spring plate in a
smoothedjawviseorholdwithpliers.Clampingshouldbedoneonats.
CAUTION
Care must be used to not damage valve surfaces.
Reassembly
The regulator is reassembled in the reverse order of disassembly, observing the following
precautions. Please reference the Bill of Material and Assembly Drawing for the correct
locationofreplacementpartsandcorrecttorquespecications.
1. Inspect all parts and replace those worn or damaged with TESCOM replacement
parts.
2. All parts should be cleaned to the cleanliness level required for safe operation with
themediaandsystemtheywillbeusedin.Allpartsintheowstreammustbefreeof
particles which could prevent proper seating of the main valve.
3. Applyathinuniformcoatingofuorocarbongreasetoanyorallofthefollowing
parts: Indentation of spring button, threaded portion of adjusting screw, entire
threaded area of the bonnet, all O-rings, all threaded parts internal to regulator.
NOTE: Do NOT apply any type of grease to the inlet or outlet connections.
4. Valve seats must be installed with the chamfered side towards the main valve.
5. Standard regulator with control knobs - The body and bonnet are best joined by
holding the bonnet assembly open end up and lowering all required items into place
one at a time. The last item to be placed in the body of the majority of TESCOM
regulators, is the piston sensor. Place all O-rings and back-up rings that are external
to the piston sensor in the body before placing the sensor in place. O-rings should
always be installed before back-up rings. The bonnet and body may now be attached.
This is best done by holding the body in one hand and the bonnet in the other. Tilt the
bodyata45°angleandthenattachthebonnetbyscrewingitintothebodyrmly,
hand tight. Regulator should then be placed in vise and bonnet re-torqued to correct
specications.SeeAssemblyDrawing.
6. Dome/Spring combination and Dome Loaded regulators are more easily reassembled
byholdingregulatorrmlyinviseandreinstallingdome.
3.4.5