Type
5All Non-Metallic Non-Replaceable Diaphragm Seal (160 psi max)
Product page
NOSHOK
Type 5 All Non-Metallic Non-Replaceable Diaphragm Seals
NOSHOK Type 5 All Non-Metallic Non-Replaceable Diaphragm Seals provide complete metallic isolation for pressure measurement instruments on ultra-pure, demineralized, or highly aggressive chemical lines. Built with 100% non-metallic wetted surfaces, they protect dial pressure gauges (2-1/2" to 6"), electronic pressure transducers, transmitters, and pressure switches from aggressive acids (such as sulfuric, hydrochloric, and nitric acids), caustics, chlorine solutions, and deionized water. The upper housing is molded from durable fiberglass-reinforced Polypropylene (PP), while the process-wetted lower housing is available in PVC, PP, or PVDF (Kynar). A heavy-duty EPDM diaphragm with a bonded virgin PTFE process-side barrier provides superior chemical inertness and an exceptional volumetric displacement of 8.9 ml, ensuring high measurement sensitivity and low temperature error even on low-pressure spans up to 160 psig (11 bar).
100% non-metallic wetted construction guarantees total chemical immunity and eliminates metallic contamination
Protects pressure gauges (2-1/2" to 6"), transducers, transmitters, and switches on aggressive and ultra-pure lines
PTFE-coated EPDM diaphragm standard across all assemblies for maximum acid, caustic, and solvent resistance
Extra-large volumetric displacement of 8.9 ml delivers outstanding sensitivity and minimal thermal drift
Ready for quotationShare your range, connection and case requirement.
Talk to ATHSeal typeThreaded, all non-metallic non-replaceable diaphragm seal
Working pressure limit0 psig to 160 psig (11 bar) maximum; minimum range 0 psig to 30 psig
Instrument compatibilityGauges (2-1/2" to 6"), pressure transducers/transmitters, and switches
Diaphragm & Displacement1.77" (45 mm) diameter; EPDM with PTFE coating on process side; 8.9 ml displacement
Upper housingPolypropylene (PP), fiberglass reinforced; non-continuous duty
Lower housingPVC (Polyvinyl chloride), PP (Polypropylene), or PVDF (Polyvinylidene fluoride)
Instrument connections1/4" NPT female (code 02) or 1/2" NPT female (code 04)
Process connections1/4" NPT female (code 02, 1/4" inst only) or 1/2" NPT female (code 04)
DimensionsOuter diameter: 3.15" (80 mm); Height: 3.39" (86 mm)
Wetted surfaces100% non-metallic (PTFE-faced EPDM diaphragm and PVC/PP/PVDF body)
Part number example5 - 04 PP - E - 04 PV
Technical data
Selection and ordering reference
Configure instrument connection size, lower housing thermoplastic material (PVC, PP, or PVDF), and process connection size for NOSHOK Type 5 Diaphragm Seals.
Max pressure160 psig (11 bar)
Wetted parts100% Non-Metallic
Displacement8.9 ml (Ultra-High)
DiaphragmPTFE-Coated EPDM
Body plasticsPVC, PP, or PVDF
Outer diameter3.15" (80 mm)
Instrument Connection & Upper Housing
02 PP1/4" NPT female, Fiberglass-reinforced Polypropylene upper housing
04 PP1/2" NPT female, Fiberglass-reinforced Polypropylene upper housing
Diaphragm Material
EEPDM diaphragm with virgin PTFE coating on process side (standard)
Process Connection & Lower Housing
02 PV1/4" NPT female, PVC lower housing (*1/4" inst only)
04 PV1/2" NPT female, PVC lower housing
04 PP1/2" NPT female, Polypropylene (PP) lower housing
04 KN1/2" NPT female, PVDF (Kynar) lower housing
Part number example
5 - 04 PP - E - 04 PV
5TypeNon-metallic diaphragm seal
04 PPInstrument1/2" NPT PP upper
EDiaphragmPTFE-coated EPDM
04 PVProcess1/2" NPT PVC lower
Technical specifications
Working pressure0 psig to 160 psig (11 bar)
Housing diameter3.15" (80 mm)
Displacement8.9 ml
Upper materialPP, fiberglass reinforced
Lower materialsPVC, PP, or PVDF (Kynar)
Diaphragm barrierPTFE on process side
Operating notes
100% non-metallic wetted design prevents chemical corrosion and eliminates metallic ions.
Extra-large 8.9 ml volumetric displacement provides high sensitivity for low-pressure ranges.
Thermoplastic housings allow seamless solvent weld or threaded integration into plastic piping.
Product Description
NOSHOK Type 5 Diaphragm Seals are engineered specifically for chemical feed, water treatment, and high-purity fluid handling where metallic wetted materials cannot be tolerated due to rapid chemical attack or metal ion contamination. Utilizing a solid polymer construction, these seals isolate gauges and electronic transmitters from hostile reagents including sodium hypochlorite, sulfuric acid, hydrochloric acid, ferric chloride, and demineralized water.
The diaphragm features an elastomer EPDM core bonded with a virgin PTFE barrier on the process side, providing the flexibility required for rapid pressure transfer alongside the universal chemical resistance of fluoropolymers. With an industry-leading 8.9 ml displacement, Type 5 seals effortlessly drive large 4-1/2" and 6" dial gauges without sluggishness or thermal span distortion.
100% metal-free process contact prevents corrosion in aggressive acids, bleach, and caustics
High displacement of 8.9 ml ensures instantaneous pressure response and high accuracy
PVDF, PP, and PVC lower housing choices allow direct compatibility with plastic piping systems
Protects delicate electronic sensors from plugging, crystallization, and chemical permeation
Robust fiberglass-reinforced polypropylene bonnet provides high mechanical rigidity
Ordering Information
Type5 (All non-metallic, non-replaceable diaphragm seal)
Instrument connection sizes02 = 1/4" NPT female; 04 = 1/2" NPT female
Upper housing materialPP = Polypropylene, fiberglass reinforced
Diaphragm materialE = EPDM with PTFE coating on process side
Process connection sizes02 = 1/4" NPT female (only with 1/4" NPT inst); 04 = 1/2" NPT female
Lower housing materialsPV = PVC (Polyvinyl chloride); PP = Polypropylene; KN = PVDF (Polyvinylidene fluoride / Kynar)
Part Number Example
Standard example5 - 04 PP - E - 04 PV
Type5 = All non-metallic diaphragm seal
Instrument connection & upper04 PP = 1/2" NPT instrument connection, Polypropylene upper housing
Diaphragm materialE = EPDM diaphragm with PTFE coated process side
Process connection & lower04 PV = 1/2" NPT process connection, PVC lower housing
Product Specifications
Pressure limit0 psig to 160 psig (11 bar) maximum operating pressure
Volumetric displacement8.9 ml (ultra-high displacement for exceptional sensitivity)
Diaphragm diameter1.77" (45 mm) active diameter
Housing diameter3.15" (80 mm) flanged outer diameter
Height3.39" (86 mm) total assembled height
Wetted materialsPTFE coated EPDM diaphragm; PVC, PP, or PVDF lower housing
Operating temperaturePVC: up to 140 °F (60 °C); PP: up to 180 °F (82 °C); PVDF: up to 212 °F (100 °C)
Operating & Selection Notes
Material Compatibility: Select PVC for economical water and mild chemical service, Polypropylene (PP) for broad acid/alkali handling, and PVDF (Kynar) for severe oxidizing acids, hot caustics, and ultra-pure deionized water.
Pressure-Temperature Derating: Maximum working pressure of thermoplastic housings decreases at elevated operating temperatures. Always verify the process pressure against the temperature limit of the chosen plastic material.
Fill Fluid Compatibility: Ensure the hydraulic fill fluid (typically Glycerin or Silicone oil) is compatible with the process in the event of unforeseen diaphragm rupture.
Do not over-torque threaded plastic connections during field installation; use PTFE thread sealant tape.
Extra-large 8.9 ml displacement easily drives 2-1/2", 4", 4-1/2", and 6" gauges as well as pressure transmitters.
100% non-metallic design prevents metallic leaching in high-purity semiconductor and RO water systems.