- 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
Pressure Instruments
SJ Gauge specializes in a wide range of professional pressure measurement instruments, including digital pressure gauges, differential pressure gauges, stainless steel mechanical gauges, and pressure transmitters. Our products are manufactured under strict quality control standards and are designed to meet diverse industrial and scientific applications. With a comprehensive product portfolio and reliable after-sales service, we ensure long-term performance and peace of mind for our customers.
We offer flexible customization services tailored to your specific requirements. From pressure gauges to transmitters, each product can be engineered to match your exact application needs. Whether for large-scale industrial procurement or low-volume customized orders without minimum quantity limitations, SJ Gauge provides fast response and efficient solutions. We understand the complexity of different operating environments and are committed to transforming your requirements into precise and reliable measurement solutions. For any customization inquiries, please feel free to contact us.
Pressure Instruments FAQ
Selection questions for pressure gauges, transmitters, switches, diaphragm seals, and pressure accessories.
How should I choose between a pressure gauge, pressure transmitter, and pressure switch?
Use a pressure gauge when local visual indication is enough, a pressure transmitter when the pressure signal must be sent to a PLC or monitoring system, and a pressure switch when equipment must start, stop, or trigger an alarm at a preset pressure. Many systems combine more than one instrument for local reading, remote monitoring, and control protection.
When is a diaphragm seal needed for pressure instruments?
A diaphragm seal is recommended when the process media is corrosive, viscous, high-temperature, crystallizing, contaminated, or sanitary. It isolates the measuring instrument from direct media contact and helps extend instrument life in chemical, food, pharmaceutical, semiconductor, petrochemical, and wastewater applications.
Which accessories help protect pressure instruments?
Siphon tubes reduce heat from steam service, snubbers damp pressure pulsation, overpressure protectors help prevent overload damage, and manifolds or gauge cocks allow isolation, venting, and maintenance. Accessory selection depends on temperature, vibration, pressure spikes, and maintenance requirements.
Can SJ Gauge customize pressure instruments?
Yes. SJ Gauge can customize pressure range, connection type, wetted material, mounting direction, electrical output, alarm contact, dial size, diaphragm seal, capillary, and accessory combinations based on the application environment.
Showing 33–48 of 91 results
Model: DIPIDiaphragm Seal for Pulp and Paper Industry
Model: DIHODiaphragm 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
Model: DIHIDiaphragm 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
Model: PRDCDifferential Pressure Gauge, All-metal Media Chamber
- Feature a highly corrosion-resistant all-metal construction and measuring cell protected against tampering
- Used for pump monitoring and control, filter monitoring and level measurement
- For gaseous and liquid aggressive media that are not highly viscous or crystallizing, also in aggressive environments
Model: PRMDDifferential Pressure Gauge, Low Differential Pressure
- Measures the small pressure difference between two pressure sources
- Only suitable for measuring gases, can not measure liquid
- Used in hospitals, laboratories, factories, gas stations and storage tanks
- Same specifications as Series 2000 magnehelic®
Model: PRHDDifferential Pressure Gauge, Double Diaphragm
- High working pressure (static pressure) and high overload safety, selectable ranges up to 30 MPa
- The use of high-quality stainless steel materials and the robust design are geared to applications in the chemical and process engineering industries
- Suitable for liquid and gaseous media in aggressive environments
- Equivalent specifications that closely match the WIKA 732.14
Model: PRLDDifferential Pressure Gauge, Cryogenic Tanks
- Supports cryotechnology; applicable for measuring low-temperature mediums
- Oil-free is available for measuring special gases such as flammable and explosive gases
- Commonly used to measure closed tank truck liquid levels for oil, liquid nitrogen, and other materials; also useful for filter monitoring
◼️ Fig.1: Differential pressure gauge model PRLD
◼️ Fig.2: With Option valve manifold with working pressure indication
Model: PRE4.HMagnetic Snap-Action Electric Contact Pressure Gauge
- Stainless steel bezel and instrument glass for durability and clear readability
- Multiple switch contact configurations available
- Suitable for chemical processing, oil and gas, steel, and machinery applications
- Specifications comparable to WIKA PGS23
Model: PRE3Electric Contact Gauge, 3 inches
- Suitable for observation and automatic control
- Adjustable magnetic strength to avoid frequent, accidental collision of contacts due to vibration
- A variety of contact types to choose from
Model: PRE-IDTElectric Contact Gauge, inductive contact
- Spark-free operation and low-energy signals, ensuring safety in explosive environments.
- A Various contact types available
- Used in chemical, petroleum, metallurgy, machinery and other industries
- Same specifications as WIKA 831
- Switch Contact Pressure Gauge, Euro Warning/Alarm Contact
Model: PRE-XSElectric Contact Gauge, explosion-proof
- Suitable for observation and automatic control
- Adjustable magnetic strength to avoid frequent, accidental collision of contacts due to vibration
- A variety of contact types to choose from
Model: PRSMDDifferential Pressure Switch
- Easy installation and no power supply needed
- Easily set the differential pressure switch values on the site
- Limited to non-flammable and non-corrosive gases
- Usually used in filter, fan, and duct pressure monitoring in building automation systems in the HVAC
Model: PRMDSDifferential Pressure Gauge, Mini
- Small size with simple construction
- Removable lens and rear-housing
- Used in air conditioners, medical respiratory equipment and filters
Model: PRDDDifferential Pressure Gauge, Duplex
- The pressure gauges are equipped with two independently working bourdon tube measuring systems
- LED lighting for operating voltages of DC24V or AC110V
- Typically used in filters and rail braking systems
Model: MPSMechanical Pressure Switch, Compact
- Automatically resetting switch design
- Wide pressure range, apply to multi work situation
- Application to air、water pressure control, Indoor air conditioner system or more…
Model: MSFZ20~50Valve Manifold for Pressure Instrument
- Divided into 2-valve manifolds, 3-valve manifolds, and 5-valve manifolds based on the applications
- Shut-off, pressure compensating, purge and vent valves for differential pressure measuring instruments
- Widely used in industries of petroleum, chemical, metallurgical, power, liquid, natural gas, and various conveying pipelines
◼️ Figure 1, 2: MSFZ20, 2-valve manifold
◼️ Figure 3, 4: MSFZ30, 3-valve manifold
◼️ Figure 5, 6: MSFZ50, 5-valve manifold