TEMBO / TGDEU - TGDEF series
Dielectric Unions & Flanges
Separate steel from brass and copper at the joint so the connection does not turn into a galvanic cell — threaded unions to 2", flanged unions to 8", each with a nylon insulator and an elastomer gasket breaking the metal-to-metal path.
Threaded rating25 bar362 psi, 1/2"-2"
Max temperature82°C180°F
Size range1/2"-8"Threaded and flanged
Overview
Break the galvanic path, keep the joint serviceable.
Where steel pipework meets brass or copper in a wet system, the two metals and the water form a galvanic cell and the less noble metal corrodes at the joint. A dielectric union interrupts that path: the steel half and the brass half never touch, separated by a nylon insulator and an elastomer gasket, so the connection is electrically broken while staying pressure-tight.
The threaded range covers six connection patterns across 1/2", 3/4", 1", 1-1/4", 1-1/2", and 2" — female or male NPT iron pipe thread against female, male, or solder-end brass. All share the same build: zinc-coated steel IPS connection and nut, nitrile gasket, nylon insert, and a brass connection, rated 25 bar (362 psi) at up to 82°C (180°F).
Above 2" the range moves to flanged unions in 2-1/2", 3", 4", 5", 6", and 8", built from a galvanized cast iron flange, an EPDM gasket, a bronze flange, a nylon insulator, and zinc-coated bolts. Welded-to-steel patterns are rated 12.1 bar (175 psi); the female x BPT pattern is rated 16 bar (232 psi) in 2-1/2" to 4", with 6" and 8" available on request.
Combined Cooperation supplies the TEMBO dielectric range in Kuwait for FCU and AHU header connections, plantroom tie-ins, and any point where a copper or brass service meets steel distribution pipework.
Nylon insulator
Breaks for service
Ten connection patterns
Up to 25 bar
Technical specifications
Threaded patternsFPT x FPT, FPT x MPT, FPT x brass weld, MPT x brass weld, MPT x brass MPT, MPT x brass FPT
Threaded sizes1/2", 3/4", 1", 1-1/4", 1-1/2", 2"
Threaded rating25 bar (362 psi) at 82°C (180°F)
Threaded materialsZinc-coated steel IPS connection and nut, brass connection, nitrile gasket, nylon insert
Flanged sizes2-1/2", 3", 4", 5", 6", 8"
Flanged rating12.1 bar (175 psi) welded patterns; 16 bar (232 psi) female x BPT
Flanged materialsGalvanized cast iron flange, bronze flange, EPDM gasket, nylon insulator, zinc-coated steel bolts
Max temperature82°C (180°F) across both ranges
Sizes & specifications
Dielectric union — threaded range (25 bar, 82°C)
| Pattern | Product code | Connection | Sizes |
|---|---|---|---|
| FPT x FPT | TGDEUFF000022-060 | Female NPT iron to female brass | 1/2" - 2" |
| FPT x MPT | TGDEUFM000022-060 | Female NPT iron to male brass | 1/2" - 2" |
| FPT x brass weld | TGDEUFW000022-060 | Female NPT iron to brass solder end | 1/2" - 2" |
| MPT x brass weld | TGDEUMW000022-060 | Male NPT iron to brass tube end | 1/2" - 2" |
| MPT x brass MPT | TGDEUMM000022-060 | Male NPT iron to male brass | 1/2" - 2" |
| MPT x brass FPT | TGDEUMF000022-060 | Male NPT iron to female brass | 1/2" - 2" |
Size codes run 022 (1/2"), 027 (3/4"), 034 (1"), 042 (1-1/4"), 048 (1-1/2"), 060 (2"). Flanged unions above 2" use the TGDEF and TGFF series in 2-1/2" to 8" — send the size and connection type and we will confirm the pattern.
Questions & answers
Common questions about dielectric unions & flanges.
01When does a project actually need a dielectric union?
Wherever a copper or brass service connects to steel pipework in a wet system — FCU and AHU coil hook-ups, header take-offs, water heater connections, and plantroom tie-ins. Without the break, the joint becomes a galvanic cell and the steel side corrodes first, usually out of sight inside the fitting.
02What is the difference between the threaded and flanged patterns?
Size and rating. Threaded unions cover 1/2" to 2" and are rated 25 bar (362 psi); flanged unions cover 2-1/2" to 8" and are rated 12.1 bar (175 psi) for the welded-to-steel patterns or 16 bar (232 psi) for the female x BPT pattern. Both are limited to 82°C (180°F).
03Which connection combinations are available?
Six on the threaded range: female or male NPT iron pipe thread against female brass, male brass, or a brass solder end. The flanged range adds welded-to-steel-pipe patterns against FPT brass, MPT brass, or a brazed copper end, plus a steel FPT x MPT brass pattern and a female x BPT pattern.
04Can you quote from an HVAC accessory schedule?
Yes. Send the schedule or BOQ with the size, the two pipe materials being joined, and the connection type at each end, and we will return the matching TEMBO product codes and indicative pricing.
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Request a quote for dielectric unions & flanges.
Send the BOQ, support schedule, or consultant specification and our technical team will come back with selections, compliance notes, and indicative pricing.
Supplied onKNPC Mina Abdullah RefineryJaber Al Ahmad HospitalShuwaikh Power PlantAll 11 Kuwait references
Get in touch
Quotes are returned within 24–48 hours.
Phone +965 2475 6717Email info@combinedcooperation.comOffice Office No. 8, 4th Floor, Mubarak Al Tijari Building, Farwaniya, Kuwait