Selecting the Correct Diaphragm Seal

Choosing the Correct Diaphragm Seal
Mansfield & Green diaphragm seals come in a variety of designs ranging from low cost gauge protectors and welded metal diaphragm units, to seals with removable metal, TEFLON, or elastomer diaphragms ideal for field replacement. Available standard ranges are from 29" Hg vacuum (736mm Hg at 0°C) to pressures up to 2500 psig (176 bar). Optional ranges are available up to 5000 psig (690 bar).

Seal Mounting Criteria 

The type of seal mounting used is particular to the type of application where the seal element will be used.

  • Thread attached seal elements are used when the seal may be easily installed on a threaded process pipe.
  • Flange attached are required in piping system with flange connections per ANSI B16.5. These seals are limited to the pressure rating equal to the flange class pressure rating.
  • In-Line Flow Thru is used in applications where process pressure measurement is required in flowing pipeline. AMETEK offers several styles to choose from.

  • Mansfield & Green diaphragm seals are constructed of materials suitable for all types of applications and process media. Utmost care should be exercised when specifying to insure material compatibility with your specific requirement.

    Seals for Every Application

    Type C Series

    These quick-couple, one-piece seals are designed to meet 3A standard requirements for sanitary piping in food, beverage, pharmaceuticals, and other industries.

    Type E Series

    One of AMETEK’s most economical seal designs, these units feature a unique construction that is free of bolts.

    Type EW seals protect against leakage and fugitive emissions as defined by the EPA Clean Air Act of 1990. Available with ranges up to 5000 psig (Type ES up to 2000 psig), they can be supplied with male threads for direct connection to the process without the need for additional fittings.

    Type L Series

    For demanding low-pressure applications, the Type L Series elements provide users with a cost-effective solution. These seals feature a removable elastomer diaphragm for pressure ranges from 29" Hg vacuum to 1250 psig at 100°F (88 bar at 38°C).

    Type XR Series

    The XR Series was designed for applications where safety is a top priority. It has a 4:1 safety ratio and is welded to a USG process or liquid filled gauge. Welding the seal to the gauge reduces leak paths, as well as possible tampering after the unit is in service. The XR Series is available in 316L SST with cooling fins or in the welded style in Hastelloy C, MONEL or Tantalum.

    Type R Series

    Used in general purpose applications, this seal element has a removable metal diaphragm. Ideal for applications from 15 to 2500 psig at 100°F (1 to 176 bar at 38°C), these elements feature a diaphragm that is easily replaced by the user. These seals are available in a variety of diaphragm materials.

    Type S Series

    Economical seal incorporates a diaphragm welded permanently to the top housing. Welded metal seals are ideal for general purpose applications with ranges from 15 to 2500 psig at 100°F (1 to 176 bar at 38°C). Optional ranges are available up to 5000 psig (690 bar).

    Type SCE Series

    This particular type of seal is ideal for applications where piping or insulation requires extension of the diaphragm into the flow-stream of the process media. They are also suitable for tank level applications.

    Type SCW Series

    Designed for applications requiring control of fugitive emissions, toxic and explosive media, these all-welded seals are available with ranges from 10 psig to Class 300.

    Type SMJ and SNJ Series

    These seal elements are used in applications where there is a jacketed pipeline and where heated or cooled processes are involved. The Type SMJ conforms to Schedule 40 process pipe rating (other schedules available). Type SNJ seals meet ANSI flange pressure/temperature ratings.

    Type ST Series

    Type ST Series is specifically designed to protect electronic transmitters, DP transmitters, transducers, and low pressure gauges against process media damage in a wide variety of process control and pipeline applications. Ideal for transmitter applications where closed systems require high sensitivity, this series provides superior accuracy where greater volumetric displacement is required.

    Type T Series

    The T Series is ideal for pressure ranges from 10 psi to 2500 psi. These seal elements feature a TEFLON diaphragm that is field replaceable. They are ideal for corrosive applications with ranges from 10 to 2500 psig at 100°F (0.8 to 176 bar at 38°C). These seals are suitable for applications with a temperature range of -40 to 400°F (-40 to 204°C).