What is a Multiseal Tapping Tee Underclamp?
A PE100 electrofusion Multiseal tapping tee underclamp provides a direct service connection from a live or dead PE main — the underclamp wraps around the main pipe, the fusion mat is welded to the pipe wall, and the outlet creates a branch for service lines from DN40 to DN225mm mains with 20-32mm outlets.
It delivers security, safety, simplicity and speed at the point of installation. The tamper-proof LockCap guarantees correct installation — it cannot be over-tightened and won't vibrate loose — while two O-ring seals protect against leakage. An optional cutter tube locks into the integral cutter for a leak-free cut-through of the main pipe.
Manufactured from virgin PE100 black polyethylene, rated PN16 for water and 10 bar for gas. For UK gas applications: 5.5 bar Class B / 7 bar Class C (size and outlet dependent). Operating temperature range: -10°C to +40°C.
Typical Applications
- Live-main service connections without interrupting flow
- Gas network branch connections to district networks
- Water utility service tappings from distribution mains
- Irrigation lateral connections from trunk lines
- Mining process water service branches
- Rapid repair and retrofit of existing PE networks
Key Features & Benefits
- Manufactured using virgin PE100 black polyethylene for long-term durability
- Water PN16 / Gas 10 Bar rating (dependent on PE pipe welded)
- Live or dead main connection — no need to shut down the pipeline
- Tamper-proof LockCap — cannot be over-tightened, won't vibrate loose
- Two O-ring seals protect against leakage at the clamp interface
- Optional cutter tube locks into the integral cutter for leak-free cut-through of the main pipe
- Double spigot outlet — sufficient spigot length to cut off the coupler and fuse a second fitting
- Optimised saddle and fusion mat minimize joint cycle times
- 4mm automatic pin — auto-detects welding parameters, prevents operator error
- SDR range 11–17.6, covering common PE pipe wall thicknesses
- Rising pin fusion indicators allow easy visual monitoring of the fusion process
- Welding parameters moulded directly into the fitting body
- Individually numbered for precise batch tracking and quality control
- Permanent batch number clearly marked for traceability
- Barcode and QR code enables full traceability back to raw materials
- Welding barcode compliant with ISO 13950; traceability barcode compliant with ISO 12176-4
- Fully welded joint — no gaskets, no flanges, no future maintenance
Reference Numbers & Dimensions
| Ref. No. |
Size (mm) |
L10 (mm) |
H (mm) |
H1 (mm) |
W10 (mm) |
SDR |
Fusion (s) |
Cooling (min) |
Weight (kg) |
Notes |
| MTBKHFA40X20U |
40×20 |
105 |
110 |
50 |
120 |
11 |
40 |
3 |
0.360 |
Underpart with single screw |
| MTBKHFA40X25U |
40×25 |
105 |
110 |
50 |
120 |
11 |
40 |
3 |
0.367 |
Underpart with single screw |
| MTBKHFA40X32U |
40×32 |
105 |
110 |
50 |
120 |
11 |
40 |
3 |
0.366 |
Underpart with single screw |
| MTBKHFA50X20U |
50×20 |
105 |
110 |
50 |
120 |
11 |
40 |
3 |
0.380 |
Underpart with single screw |
| MTBKHFA50X25U |
50×25 |
105 |
110 |
50 |
120 |
11 |
40 |
3 |
0.380 |
Underpart with single screw |
| MTBKHFA50X32U |
50×32 |
105 |
110 |
50 |
120 |
11 |
40 |
3 |
0.390 |
Underpart with single screw |
| MTBKHFA63X20U |
63×20 |
105 |
119 |
62 |
120 |
11–17.6 |
80 |
10 |
0.524 |
|
| MTBKHFA63X25U |
63×25 |
105 |
119 |
62 |
120 |
11–17.6 |
80 |
10 |
0.537 |
|
| MTBKHFA63X32U |
63×32 |
105 |
119 |
62 |
120 |
11–17.6 |
80 |
10 |
0.530 |
|
| MTBKHFA75X20U |
75×20 |
105 |
110 |
77 |
120 |
11–17.6 |
90 |
10 |
0.658 |
|
| MTBKHFA75X25U |
75×25 |
105 |
110 |
77 |
120 |
11–17.6 |
90 |
10 |
0.676 |
|
| MTBKHFA75X32U |
75×32 |
105 |
110 |
77 |
120 |
11–17.6 |
90 |
10 |
0.675 |
|
| MTBKHFA90X20U |
90×20 |
105 |
110 |
77 |
120 |
11–17.6 |
90 |
10 |
0.600 |
|
| MTBKHFA90X25U |
90×25 |
105 |
110 |
77 |
120 |
11–17.6 |
90 |
10 |
0.600 |
|
| MTBKHFA90X32U |
90×32 |
105 |
110 |
77 |
120 |
11–17.6 |
90 |
10 |
0.617 |
|
| MTBKHFA110X20U |
110×20 |
105 |
117 |
87 |
120 |
11–17.6 |
80 |
10 |
0.644 |
|
| MTBKHFA110X25U |
110×25 |
105 |
117 |
87 |
120 |
11–17.6 |
80 |
10 |
0.647 |
|
| MTBKHFA110X32U |
110×32 |
105 |
117 |
87 |
120 |
11–17.6 |
80 |
10 |
0.650 |
|
| MTBKHFA125X20U |
125×20 |
105 |
117 |
95 |
120 |
11–17.6 |
80 |
10 |
0.650 |
|
| MTBKHFA125X25U |
125×25 |
105 |
117 |
95 |
120 |
11–17.6 |
80 |
10 |
0.660 |
|
| MTBKHFA125X32U |
125×32 |
105 |
117 |
95 |
120 |
11–17.6 |
80 |
10 |
0.666 |
|
| MTBKHFA160X20U |
160×20 |
105 |
122 |
112 |
120 |
11–17.6 |
100 |
10 |
0.730 |
|
| MTBKHFA160X25U |
160×25 |
105 |
122 |
112 |
120 |
11–17.6 |
100 |
10 |
0.726 |
|
| MTBKHFA160X32U |
160×32 |
105 |
122 |
112 |
120 |
11–17.6 |
100 |
10 |
0.713 |
|
| MTBKHFA180X20U |
180×20 |
105 |
122 |
122 |
120 |
11–17.6 |
100 |
10 |
0.740 |
|
| MTBKHFA180X25U |
180×25 |
105 |
122 |
122 |
120 |
11–17.6 |
100 |
10 |
0.745 |
|
| MTBKHFA180X32U |
180×32 |
105 |
122 |
122 |
120 |
11–17.6 |
100 |
10 |
0.731 |
|
| MTBKHFA200X20U |
200×20 |
105 |
122 |
132 |
120 |
11–17.6 |
100 |
10 |
0.730 |
|
| MTBKHFA200X25U |
200×25 |
105 |
122 |
132 |
120 |
11–17.6 |
100 |
10 |
0.730 |
|
| MTBKHFA200X32U |
200×32 |
105 |
122 |
132 |
120 |
11–17.6 |
100 |
10 |
0.730 |
|
| MTBKHFA225X20U |
225×20 |
105 |
122 |
145 |
120 |
11–17.6 |
100 |
10 |
0.760 |
|
| MTBKHFA225X25U |
225×25 |
105 |
122 |
145 |
120 |
11–17.6 |
100 |
10 |
0.784 |
|
| MTBKHFA225X32U |
225×32 |
105 |
122 |
145 |
120 |
11–17.6 |
100 |
10 |
0.776 |
|
Note: Sizes DN40-50 use an underpart with a single screw clamp. All stated technical specifications depend on the PE pipe welded to and local pipeline pressure regulations. SDR 11 applies to DN40-50; SDR 11-17.6 applies to DN63-225. Please contact us for detailed CAD drawings.
Product Standards & Certifications
Our electrofusion tapping tees are designed and manufactured to meet international product standards, backed by ISO 9001 and ISO 29001 quality management system certifications. The Fusamatic range is third-party certified against the standards below.
- EN ISO 15494 — Plastics piping systems — Polyethylene (PE) for industrial applications (3rd party approved)
- EN 12201-3 — Plastics piping systems for water supply — Polyethylene (PE) — Part 3: Fittings (3rd party approved)
- EN 1555-3 — Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — Part 3: Fittings (3rd party approved)
- ISO 4437-3 — Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — Part 3: Fittings (3rd party approved)
- ISO 4427-3 — Plastics piping systems for water supply — Polyethylene (PE) — Part 3: Fittings (3rd party approved)
- Welding barcode compliant with ISO 13950
- Traceability barcode compliant with ISO 12176-4
Note: Regional variations may apply. Other product certificates available upon request.
Shipping & Delivery Information
We export PE electrofusion tapping tees worldwide. Small sizes are packed in cartons on pallets; larger sizes are individually polybagged and crated for safe sea freight.
After-Sales Service & Warranty
We stand behind the quality of our electrofusion fittings. Our commitment doesn't end at delivery — we provide comprehensive technical support for your PE pipeline project.
Frequently Asked Questions
Common questions about our Multiseal tapping tee underclamp
What is an electrofusion tapping tee underclamp used for?+
An underclamp tapping tee provides a direct service connection from a live or dead PE main, allowing branch lines to be added to DN40-DN225mm mains with 20-32mm outlets — without interrupting the main line.
What is the Multiseal LockCap?+
The tamper-proof LockCap ensures correct installation — it cannot be over-tightened and won't vibrate loose, guaranteeing a secure seal during operation. Two O-ring seals provide additional leak protection.
What pressure ratings are supported?+
This tapping tee is rated PN16 for water applications and 10 bar for gas applications. For UK gas applications it supports 5.5 bar (Class B) and 7 bar (Class C), size and outlet dependent.
What outlet sizes are available?+
33 combinations from DN40x20 to DN225x32mm are available, with 20mm, 25mm and 32mm outlets on mains from DN40 to DN225mm. All use a 4mm automatic pin.
What is the minimum order quantity?+
The standard MOQ is 100 pieces per size, but we are flexible for trial orders. Smaller sample quantities are available for evaluation. Contact us with your required sizes and quantity for a tailored quote.
Your message must be between 20-3,000 characters!
