Temperature Instruments

DOE-HDBK-1132-99

Pulsation dampers should be used on all pulsating services, such as

reciprocating pumps and compressors or other applications where severe

service from pulsating pressure is anticipated.

Diaphragm seals should be provided where

corrosive material is being measured and suitable element

material is not available;

material with a freezing temperature higher than the minimum

ambient temperature is being measured; and

material contains solid matter that could plug the instrument.

Gauges should not be installed adjacent to sources of heat that could

potentially raise their temperature to above 200 EF.

Gauges on gas and vapor services should be installed above the process

tap. If it is necessary to install gauges on gas or vapor services below the

process tap, they may need to be heat traced and insulated to prevent

A pair of differential pressure sensing lines may need an equalizing valve

to prevent over-pressurization of the instrument and a drain valve on one

line.

Temperature Instruments . Temperature instruments should be installed in a

4.9.4

thermowell to allow removal without process disturbance. Adequate space

should be provided to allow removal of thermocouples, resistance temperature

detectors, thermal bulbs, or indicators.

II-51