Flanged Connection, Upper Metal, Lower Plastic

Diaphragm Seal

SJ Gauge offers a wide range of diaphragm seal solutions for pressure gauges and pressure transmitters, including single flange, double flange, sanitary type, threaded type, and special diaphragm seals, which can be selected based on different media characteristics and installation requirements.

When the measured media is viscous, paste-like, crystallizing, particle-containing, or highly corrosive, diaphragm seals help protect pressure instruments by reducing the risk of clogging, corrosion, and damage, while improving measurement stability. Common applications include chemical processing, food and beverage, pharmaceutical, wastewater treatment, petrochemical, and various process industries. If you have special operating conditions or customization requirements, please feel free to contact SJ Gauge.

  • Flanged Connection, Upper Metal, Lower Plastic
    Model: DIF-USLP

    Flanged Connection, Upper Metal, Lower Plastic

    • A metal upper body that connects to the instrument is tight and durable
    • Plastic lower body can protect pressure instruments from corrosive, contaminated or viscous media
    • Suitable for paint, electroplating, sewage treatment and the paper industry
  • Flanged Connection with Dual Diaphragm
    Model: DIF-S

    Flanged Connection with Dual Diaphragm

    • Lower pressure ranges can be measured to meet pipeline connection needs and accuracy
    • An alternative when flange diaphragm seal – “I” section type cannot be used due to lack of space
    • Applicable for strict working environments including biogas, oil, gas fracking and biodiesel, etc
  • Flanged Connection with Flush Diaphragm
    Model: DIF-F

    Flanged Connection with Flush Diaphragm

    • One-piece seal design bolts directly to process flange
    • Flush-mounted diaphragm prevents clogging of process media
    • Used in applications with difficult media such as machine building and automation
  • Flanged Connection with Extended Diaphragm
    Model: DIF-E

    Flanged Connection with Extended Diaphragm

    • Upper body of the diaphragm seal, the extended diaphragm and the wetted parts can be made of identical or different materials
    • As an alternative, the diaphragm and the extended diaphragm can be coated
    • Used for contaminated, solidifying, hot or highly viscous media such as thick walled or isolated tanks and pipelines
  • Flanged Connection, Cell (Pancake) Diaphragm
    Model: DIF-C

    Flanged Connection, Cell (Pancake) Diaphragm

    • Instruments are connected via a side capillary connection and it is an ideal seal for transmitters or DP transmitters
    • Be mounted between an open process flange and an optional cover flange
    • Used for contaminated, solidifying, hot, or highly viscous media
    • An alternative with high compatibility and corresponding specifications to the WIKA 990.28
  • Flanged Connection with Stub Pipe, Screwed Diaphragm
    Model: DIFF-S

    Flanged Connection with Stub Pipe, Screwed Diaphragm

    • By using diaphragm seals, the measuring instruments can be used at extreme temperatures up to +300 °C
    • The double flange diaphragm can increase the size of the upper body and diaphragm to match the piping connection, requirements, and improve accuracy
    • Applicable to special working environments and corrosive fluids, such as high pressure, high vibration, and concrete
  • Flanged Connection with Stub Pipe, Welded Diaphragm
    Model: DIFF-W

    Flanged Connection with Stub Pipe, Welded Diaphragm

    • Optimizable through the adjustment of the upper seat and diaphragm sizes for precision and to meet the criteria for pipeline connections
    • The short pipe length on the lower body can be manufactured to match the piping’s thermal-insulation requirements.
    • Durability for working environments using liquids that are high temperature, corrosive, sewage, or prone to crystallization
  • Flanged Connection with Stub Pipe, Corrosion-resistant Plastic
    Model: DIFF-P

    Flanged Connection with Stub Pipe, Corrosion-resistant Plastic

    • Upper seat and diaphragm can be enlarged to ensure precision and compliance with pipeline connection standards
    • Applicable for media that are corrosive, viscous, powdery, harmful or toxic to the environment
    • Ideal for industries such as petrochemical, chemical equipment construction, sewage treatment, paper, etc.
  • Flanged Connection with Stub Pipe, Upper Metal, Lower Plastic
    Model: DIFF-USLP

    Flanged Connection with Stub Pipe, Upper Metal, Lower Plastic

    • Enlarged upper seat and diaphragm to enhance accuracy and meet the requirements for pipeline connections
    • The material of diaphragm or dual diaphragm can be different from the main body
    • Ideal for industries such as electroplating, chemical and petrochemical processing, etc.
  • Diaphragm Seal for Pulp and Paper Industry
    Model: DIPI

    Diaphragm Seal for Pulp and Paper Industry

    • External chemical seal with welded diaphragm, designed to suit connections in the pulp and paper industries
    • Suitable for attaching to pressure gauges, pressure switches, and pressure instruments
    • Designed to be used for highly viscous process media such as pulp and plastic, and chemicals
  • Diaphragm Seal for Homogenizer Machine
    Model: DIHO

    Diaphragm Seal for Homogenizer Machine

    • Available with process connections in various designs, fitting with all common measuring points
    • Designed to prevent aggressive or contaminating medium from entering a conventional pressure gauge
    • Widely used on homogenizers such as those found in sanitary applications, production of cosmetics and creams, dairies, and the pharmaceutical industry
  • Diaphragm Seal for Melting High Temperature
    Model: DIHI

    Diaphragm Seal for Melting High Temperature

    • Used to measure molten state process media
    • A capillary can be selected, suitable for remote observation
    • Widely used in the synthetic chemical, synthetic fiber, and plastic industries
  • Welding Tri-Clamp Diaphragm Seal for Small-size Pipeline Connections
    Model: DIT-CS

    Welding Tri-Clamp Diaphragm Seal for Small-size Pipeline Connections

    • Special design for small-size pipeline connections
    • Enlarging the upper seat and diaphragm can ensure precision and fit different pipeline connections
    • Ideal for industries such as petrochemical, chemical equipment construction, sewage treatment, paper, etc.