Heat Shrink Busbar Sleeve (BUSTUBE)
BUSTUBE is a heat-shrinkable, non-tracking cross-linked polyolefin sleeve that insulates busbar systems up to 36 kV and guards against accidental flashover — Thin Wall (to 3.3 kV), Medium Wall (to 24 kV) and Heavy Wall (to 36 kV) grades.
- ANSI C37.20.2
- IEC 71-2
- IEC 216
Choose a size
Selection Charts
- D (min.)
- Minimum inside diameter as supplied
- d (max.)
- Maximum inside diameter after recovery
- T
- Wall thickness after recovery (+5% / −2%)
- Reel length
- Supplied length in metres
- W+B
- Width plus thickness of a rectangular busbar the size fits
- Ø
- Diameter of a round busbar the size fits
| Gala size | D(min.) | d(max.) | T(+5% / −2%) | Reel length(m) | Rect. bar W+B min. | Rect. bar W+B max. | Round bar Ø min. | Round bar Ø max. |
|---|---|---|---|---|---|---|---|---|
| GMB 16/6 | 16 | 6 | 1.70 | 25 | 11 | 18 | 7 | 12 |
| GMB 25/10 | 25 | 10 | 2.50 | 25 | 16 | 30 | 12 | 20 |
| GMB 30/12 | 30 | 12 | 2.10 | 25 | 25 | 38 | 16 | 25 |
| GMB 40/16 | 40 | 16 | 2.10 | 25 | 33 | 50 | 21 | 32 |
| GMB 50/20 | 50 | 20 | 2.10 | 25 | 38 | 63 | 24 | 40 |
| GMB 65/25 | 65 | 25 | 2.20 | 25 | 53 | 82 | 34 | 52 |
| GMB 75/28 | 75 | 28 | 2.50 | 25 | 63 | 94 | 40 | 60 |
| GMB 85/32 | 85 | 32 | 2.50 | 25 | 69 | 107 | 44 | 68 |
| GMB 100/38 | 100 | 38 | 3.00 | 25 | 83 | 126 | 53 | 80 |
| GMB 120/45 | 120 | 45 | 3.00 | 25 | 104 | 150 | 66 | 96 |
| GMB 150/60 | 150 | 60 | 3.30 | 20 | 132 | 200 | 84 | 127 |
| GMB 180/72 | 180 | 72 | 3.00 | 20 | 151 | 226 | 96 | 144 |
| GMB 205/85 | 205 | 85 | 3.10 | 1.5 | 239 | 257 | 152 | 164 |
| GMB 250/100 | 250 | 100 | 3.10 | 1.5 | 264 | 314 | 168 | 200 |
Source: GALA BUSSLEEVE Heat Shrink Busbar Sleeve catalogue, Issue 2, August 2026.
Heavy wall BUSSLEEVE (GHB), up to 36 kV
| Gala size | D(min.) | d(max.) | T(+5% / −2%) | Reel length(m) | Rect. bar W+B min. | Rect. bar W+B max. | Round bar Ø min. | Round bar Ø max. |
|---|---|---|---|---|---|---|---|---|
| GHB 25/8 | 25 | 8 | 3.20 | 25 | 20 | 28 | 13 | 20 |
| GHB 30/12 | 30 | 12 | 3.50 | 25 | 28 | 33 | 18 | 25 |
| GHB 40/16 | 40 | 16 | 3.50 | 25 | 35 | 45 | 22 | 32 |
| GHB 50/20 | 50 | 20 | 3.50 | 25 | 45 | 54 | 29 | 40 |
| GHB 65/25 | 65 | 25 | 3.50 | 25 | 50 | 62 | 32 | 43 |
| GHB 75/28 | 75 | 28 | 3.50 | 20 | 53 | 69 | 34 | 47 |
| GHB 85/32 | 85 | 32 | 3.50 | 20 | 69 | 100 | 44 | 68 |
| GHB 100/38 | 100 | 38 | 3.70 | 20 | 83 | 102 | 53 | 72 |
| GHB 120/45 | 120 | 45 | 3.70 | 20 | 94 | 125 | 60 | 85 |
| GHB 150/60 | 150 | 60 | 3.70 | 15 | 122 | 168 | 78 | 105 |
| GHB 180/70 | 180 | 70 | 3.70 | 15 | 160 | 196 | 102 | 125 |
| GHB 205/85 | 205 | 85 | 3.70 | 1.5 | 239 | 250 | 152 | 164 |
| GHB 250/120 | 250 | 120 | 3.80 | 1.5 | 264 | 314 | 168 | 200 |
Source: GALA BUSSLEEVE Heat Shrink Busbar Sleeve catalogue, Issue 2, August 2026.
Thin wall BUSSLEEVE (GSC), up to 3.3 kV
| Gala size | D(min.) | d(max.) | T(+5% / −2%) | Reel length(m) | Rect. bar W+B min. | Rect. bar W+B max. | Round bar Ø min. | Round bar Ø max. |
|---|---|---|---|---|---|---|---|---|
| GSC 16/8 | 16 | 8 | 0.69 | 100 | 16 | 18 | 12 | 12 |
| GSC 20/10 | 20 | 10 | 0.78 | 100 | 22 | 25 | 14 | 16 |
| GSC 30/15 | 30 | 15 | 0.86 | 50 | 33 | 38 | 21 | 24 |
| GSC 40/20 | 40 | 20 | 0.96 | 50 | 44 | 52 | 28 | 33 |
| GSC 50/25 | 50 | 25 | 0.96 | 25 | 53 | 65 | 34 | 41 |
| GSC 60/30 | 60 | 30 | 0.96 | 25 | 64 | 75 | 41 | 48 |
| GSC 70/35 | 70 | 35 | 1.10 | 25 | 72 | 90 | 46 | 57 |
| GSC 80/40 | 80 | 40 | 1.27 | 25 | 86 | 100 | 55 | 64 |
| GSC 100/50 | 100 | 50 | 1.40 | 25 | 104 | 125 | 66 | 80 |
| GSC 120/60 | 120 | 60 | 1.40 | 25 | 110 | 150 | 70 | 96 |
| GSC 150/75 | 150 | 75 | 1.40 | 25 | 151 | 190 | 96 | 121 |
| GSC 180/90 | 180 | 90 | 1.50 | 25 | 179 | 236 | 114 | 150 |
Source: GALA BUSSLEEVE Heat Shrink Busbar Sleeve catalogue, Issue 2, August 2026.
Dimensional data
Technical Specification
| CLEARANCE WITH INSULATION | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| VOLTAGE | MEDIUM WALL TUBE(GMB) | HEAVY WALL TUBE(GHB) | UN-INSULATED BUSBARS (mm) AS PER IEC 71-2 | ||||||
| PH to PH (mm) | PH to GR (mm) | PH to PH (mm) | PH to GR (mm) | ||||||
| Rectangular | Round | Rectangular | Round | Rectangular | Round | Rectangular | Round | ||
| 12 kV | 65 | 55 | 75 | 65 | 35 | 30 | 45 | 40 | 120 |
| 17.5 kV | 85 | 70 | 105 | 85 | 55 | 50 | 65 | 60 | 160 |
| 24 kV | 115 | 95 | 150 | 125 | 70 | 60 | 100 | 90 | 220 |
| 36 kV | 200 | 150 | 285 | 205 | 140 | 130 | 190 | 180 | 320 |
Dimensions & Drawings
BUSTUBE shrinks onto the bar with heat, cutting the phase-to-phase and phase-to-earth clearance a busbar needs against the uninsulated figures in IEC 71-2 — at 36 kV, 140 mm phase-to-phase on Heavy Wall against 320 mm bare.
GSC, GMB and GHB series sizes cover both rectangular (width + breadth) and round busbars — see the selection chart below.
Covered on this page
- Heat Shrinkable Tubes/Heat Shrink Sleeves
- Thin Wall Tube [Up to 3.3KV]
- Medium Wall Tube [Upto 24KV]
- Heavy Wall Tube [upto 36KV]
Features & Benefits
- Meets ANSI C37.20.2 for MV switchgear application up to 36 kV
- Three wall grades: Thin Wall (GSC, to 3.3 kV), Medium Wall (GMB, to 24 kV), Heavy Wall (GHB, to 36 kV)
- Non-tracking, cross-linked polyolefin — halogen free, flame retardant
- Dielectric strength 22 kV/mm (min., ASTM D149); volume resistivity 1 × 10¹³ Ohm·cm (min., ASTM D257)
- Continuous temperature limit −40°C to +115°C; shrink temperature 125°C (IEC 216)
- Highly flexible for straight or angled bars without creasing
Applications
- Insulating busbar systems in switchgear and bus ducts up to 36 kV
- Reducing busbar-to-busbar and busbar-to-earth clearance
- Protecting busbars from chemical corrosion (strong acid, alkali, salt)
- Guarding against accidental flashover on straight or angled bars
Standards & Compliance
- ANSI C37.20.2
- IEC 71-2
- IEC 216
- IEC 60684-2
- ESI 09-11
- ASTM D149
- ASTM D150
- ASTM D257
- ASTM D570
- ASTM D638
- ASTM D792
- ASTM D2240
- ASTM D2671
FAQs
Frequently Asked Questions
What is the Heat Shrink Busbar Sleeve used for?
It is used for:
- Insulating busbar systems in switchgear and bus ducts up to 36 kV
- Reducing busbar-to-busbar and busbar-to-earth clearance
- Protecting busbars from chemical corrosion (strong acid, alkali, salt)
- Guarding against accidental flashover on straight or angled bars
How do I choose the right size?
A heat-shrink part is chosen by two diameters. As supplied (D (min.)) it must open wider than the largest thing it has to slide over; after shrinking (d (max.)) it must close smaller than the smallest thing it has to grip. Measure both on your cable or busbar and pick the first code in the selection chart that satisfies both.
How is it installed?
Clean and degrease the surface, position the part, then shrink it with a gas torch or a hot-air gun: keep the heat moving round it with a smooth, brushing motion so it recovers evenly without scorching. Start at one end and work steadily along to the other.
Which standards and test methods are quoted for it?
These, with the values in the Technical Specification on this page:
- ANSI C37.20.2
- IEC 71-2
- IEC 216
- IEC 60684-2
- ESI 09-11
- ASTM D149
- ASTM D150
- ASTM D257
- ASTM D570
- ASTM D638
Where can I download the datasheet?
From the "Download datasheet" button at the top of this page, or here:
Can I get a quote, a sample or a size that is not listed?
Send your cable details, quantity and application with the "Request a Quote or Sample" form at the foot of this page. For a size or variant that is not in the chart, describe what you need there, or use Technical support at the top of the page, and the technical team will confirm what can be supplied.
47+
Years manufacturing
100+
Countries served
140
Products in range
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