Brass Compression FI Straight Coupler Fitting
A professional-grade WRAS approved brass compression fitting designed to provide a secure connection between copper pipework and female threaded components. Manufactured from high-quality brass, this compression female straight connector offers excellent durability, corrosion resistance and long-term performance in plumbing and heating systems.
Brass Compression FI Straight Coupler Fitting
A professional-grade WRAS approved brass compression fitting designed to provide a secure connection between copper pipework and female threaded components. Manufactured from high-quality brass, this compression female straight connector offers excellent durability, corrosion resistance and long-term performance in plumbing and heating systems.
Product Options
| SKU | SIZE / OPTION | AVAILABILITY | PRICE | QTY | ACTION |
|---|---|---|---|---|---|
| A - 65 | IN STOCK | £0.53 Ex. VAT | |||
| A - 66 | IN STOCK | £0.65 Ex. VAT | |||
| A - 67 | IN STOCK | £0.63 Ex. VAT | |||
| A - 68 | IN STOCK | £0.78 Ex. VAT | |||
| A - 69 | IN STOCK | £0.88 Ex. VAT | |||
| A - 70 | IN STOCK | £0.96 Ex. VAT | |||
| A - 71 | IN STOCK | £0.89 Ex. VAT | |||
| A - 72 | IN STOCK | £0.91 Ex. VAT | |||
| A - 73 | IN STOCK | £0.79 Ex. VAT | |||
| A - 74 | IN STOCK | £1.17 Ex. VAT | |||
| A - 75 | IN STOCK | £1.64 Ex. VAT | |||
| A - 76 | IN STOCK | £1.30 Ex. VAT | |||
| A - 77 | IN STOCK | £1.76 Ex. VAT | |||
| A - 78 | IN STOCK | £2.16 Ex. VAT | |||
| A - 78-A | OUT OF STOCK | £3.26 Ex. VAT | |||
| A - 79 | IN STOCK | £4.79 Ex. VAT | |||
| A - 80 | IN STOCK | £5.92 Ex. VAT | |||
| A - 81 | IN STOCK | £10.63 Ex. VAT |
Quick Trade Summary: Brass Compression FI Straight Coupler
MEP Stock supplies heavy-duty forged brass compression female iron (FI) straight coupler fittings designed to transition smooth copper tube into threaded male iron BSP pipework, pump valves, gauges, or boiler tails. Precision manufactured to BS EN 1254-2 with machined internal parallel BSP threads.
Direct Copper-to-Threaded Iron Transitions for HVAC & Plant Rooms
Connecting copper domestic hot and cold pipework or central heating circuits into male-threaded pump unions, heating controls, strainers, and pressure vessels requires dependable female BSP interfaces. Our compression FI straight couplers feature reinforced hexagonal brass walls to prevent body swelling under spanner torque while maintaining certified BS EN 1254-2 olive compression.
Engineering Specifications
| Body Material | Hot Forged CW617N Brass (BS EN 1254-2) |
| Inlet Connection | Compression Nut & Brass Olive for Copper Tube (BS EN 1057) |
| Outlet Thread | Parallel Female BSP Thread (BS EN 10226 / ISO 7-1) |
| Operating Pressure | 16 bar at 30°C / 10 bar at 65°C / 6 bar at 110°C |
| Temperature Range | -10°C to +110°C |
| Compatibility | BS EN 1057 Copper, Chrome Tube, PEX/PB with Pipe Inserts |
BS EN Installation Protocol
- Step 1: Prepare Threaded Joint First — Wrap 4 to 6 turns of PTFE tape clockwise around the male mating thread.
- Step 2: Engage Female Coupler — Thread female coupler onto male thread hand-tight, then tighten securely with open-ended spanner.
- Step 3: Prepare Copper Tube — Cut copper tube square at 90°, deburr internally and externally, and slide nut and olive onto pipe.
- Step 4: Bottom Tube in Socket — Push copper tube completely into the compression socket until firmly seated.
- Step 5: Torque Compression Nut — Hand-tighten nut, then tighten 3/4 to 1 full turn beyond hand-tight using holding spanner on fitting body.
Frequently Asked Questions
What does 'Female Iron' (FI) mean on this compression coupler?
Female Iron refers to internal female BSP parallel pipe threads.
Female Iron (FI) is the traditional UK trade term for female British Standard Pipe (BSP) parallel threads, designed to accept male threaded steel, brass, or iron fittings.
Should I tighten the threaded side or compression side first?
Always tighten the threaded FI joint first before making the copper compression connection.
Always tighten the threaded FI joint first before making the copper compression connection. This prevents twisting or placing rotational stress on the copper tube and seated brass olive.
Do I need PTFE tape on the female compression side?
No. The compression side seals metal-to-metal on the olive ring.
No. The compression side seals metal-to-metal on the olive ring. Apply PTFE tape or thread sealant only to the male iron pipe entering the female BSP threaded end.
Is this FI coupler suitable for drinking water?
Yes, manufactured from high-purity brass compliant with UK Water Supply Regulations.
Yes, manufactured from high-purity brass compliant with UK Water Supply Regulations for wholesome potable drinking water.
Can this fitting be used with plastic barrier pipe?
Yes, provided manufacturer-approved rigid copper/brass pipe inserts are fitted.
Yes, provided manufacturer-approved rigid copper/brass pipe inserts are fitted inside the plastic pipe before tightening the olive.
What size combinations are available?
Available from 15mm x 1/2" up to 28mm x 1" FI BSP in single pieces and trade packs.
Available from 15mm x 1/2" up to 28mm x 1" FI BSP in single pieces and trade packs.
Order Trade Brass Compression FI Straight Couplers Online
Wide range of copper-to-female BSP thread sizes available at wholesale trade prices.
Browse Full Compression Range →Quick Trade Summary: Brass Compression FI Straight Coupler
MEP Stock supplies heavy-duty forged brass compression female iron (FI) straight coupler fittings designed to transition smooth copper tube into threaded male iron BSP pipework, pump valves, gauges, or boiler tails. Precision manufactured to BS EN 1254-2 with machined internal parallel BSP threads.
Direct Copper-to-Threaded Iron Transitions for HVAC & Plant Rooms
Connecting copper domestic hot and cold pipework or central heating circuits into male-threaded pump unions, heating controls, strainers, and pressure vessels requires dependable female BSP interfaces. Our compression FI straight couplers feature reinforced hexagonal brass walls to prevent body swelling under spanner torque while maintaining certified BS EN 1254-2 olive compression.
Engineering Specifications
| Body Material | Hot Forged CW617N Brass (BS EN 1254-2) |
| Inlet Connection | Compression Nut & Brass Olive for Copper Tube (BS EN 1057) |
| Outlet Thread | Parallel Female BSP Thread (BS EN 10226 / ISO 7-1) |
| Operating Pressure | 16 bar at 30°C / 10 bar at 65°C / 6 bar at 110°C |
| Temperature Range | -10°C to +110°C |
| Compatibility | BS EN 1057 Copper, Chrome Tube, PEX/PB with Pipe Inserts |
BS EN Installation Protocol
- Step 1: Prepare Threaded Joint First — Wrap 4 to 6 turns of PTFE tape clockwise around the male mating thread.
- Step 2: Engage Female Coupler — Thread female coupler onto male thread hand-tight, then tighten securely with open-ended spanner.
- Step 3: Prepare Copper Tube — Cut copper tube square at 90°, deburr internally and externally, and slide nut and olive onto pipe.
- Step 4: Bottom Tube in Socket — Push copper tube completely into the compression socket until firmly seated.
- Step 5: Torque Compression Nut — Hand-tighten nut, then tighten 3/4 to 1 full turn beyond hand-tight using holding spanner on fitting body.
Frequently Asked Questions
What does 'Female Iron' (FI) mean on this compression coupler?
Female Iron refers to internal female BSP parallel pipe threads.
Female Iron (FI) is the traditional UK trade term for female British Standard Pipe (BSP) parallel threads, designed to accept male threaded steel, brass, or iron fittings.
Should I tighten the threaded side or compression side first?
Always tighten the threaded FI joint first before making the copper compression connection.
Always tighten the threaded FI joint first before making the copper compression connection. This prevents twisting or placing rotational stress on the copper tube and seated brass olive.
Do I need PTFE tape on the female compression side?
No. The compression side seals metal-to-metal on the olive ring.
No. The compression side seals metal-to-metal on the olive ring. Apply PTFE tape or thread sealant only to the male iron pipe entering the female BSP threaded end.
Is this FI coupler suitable for drinking water?
Yes, manufactured from high-purity brass compliant with UK Water Supply Regulations.
Yes, manufactured from high-purity brass compliant with UK Water Supply Regulations for wholesome potable drinking water.
Can this fitting be used with plastic barrier pipe?
Yes, provided manufacturer-approved rigid copper/brass pipe inserts are fitted.
Yes, provided manufacturer-approved rigid copper/brass pipe inserts are fitted inside the plastic pipe before tightening the olive.
What size combinations are available?
Available from 15mm x 1/2" up to 28mm x 1" FI BSP in single pieces and trade packs.
Available from 15mm x 1/2" up to 28mm x 1" FI BSP in single pieces and trade packs.
Order Trade Brass Compression FI Straight Couplers Online
Wide range of copper-to-female BSP thread sizes available at wholesale trade prices.
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