Heat Shrink Busbar Sleeve - Medium Wall up to 24 kV (GMB)

About Heat Shrink Busbar Sleeve - Medium Wall up to 24 kV (GMB)

Gala's medium-wall busbar sleeve (GMB series, BUSSLEEVE range) insulates busbars in medium-voltage switchgear and bus ducts up to 24 kV. It is a cross-linked polyolefin tube supplied expanded; heated on the bar, it shrinks into a tight, continuous insulating cover that follows straight and bent bars without creasing.

Insulating the bars guards against accidental flash-over, helps switchgear designers work with reduced phase-to-phase and phase-to-earth clearances, solves insulation problems between closely spaced bars in bus ducts, and protects copper or aluminium from corrosion by acid, alkali and salt.

Fourteen sizes cover rectangular bars from 11 to 314 mm (width plus thickness) and round bars from 7 to 200 mm. Most sizes are supplied on 25 m or 20 m reels; the two largest come in 1.5 m lengths. To choose a size, add the bar's width and thickness and pick the size whose W+B range contains it.

Installation is by torch or oven. With a torch, preheat the bar, slide the sleeve into position and shrink it from one end. In an air-circulating oven, 120 to 150 deg C for an average of 10 to 15 minutes is typical, never less than 5. For bent bars a thin film of approved lubricant helps the sleeve slide on. Trim ends and punch holes after the bar has cooled.

Gala holds a POWERGRID manufacturer approval covering insulation sleeves and tapes, valid to February 2028.

Manufactured by Gala in India. Datasheet and size selection on request.

Specifications

• Brand: Gala
• Product type: Medium wall heat shrink busbar sleeve
• Material: Cross-linked polyolefin
• Colour: Brick red
• Voltage rating: Up to 24 kV
• Operating temperature: -40 deg C to +115 deg C continuous (Aug 2026 catalogue)
• Size range: GMB 16/6 to GMB 250/100; rectangular bar W+B 11 to 314 mm; round bar 7 to 200 mm
• Wall type / thickness: Medium wall, 1.70 mm to 3.30 mm after recovery (+5% / -2%)
• Standards tested to: Test methods quoted on GSF's catalogue - ASTM D638, ASTM D570, ASTM D792, ASTM D2240, ASTM D2671, ASTM D257, ASTM D150
• Application: Insulation of busbars in MV switchgear, panels and bus ducts
• Installation: Torch (preheat bar, shrink from one end) or air-circulating oven at 120 to 150 deg C for 10 to 15 minutes
• Country of origin: India
• Shrink temperature: 125 deg C
• Tensile strength: 9 N/mm2 min
• Elongation at break: 350% min
• Density: 1.20 +/- 0.2 g/cm3
• Hardness: 45 +/- 10 Shore D
• Water absorption: 0.5% max
• Heat shock: 250 deg C for 30 min, no cracking or flowing
• Low temperature flexibility: -40 deg C for 4 h, no cracking
• Volume resistivity: 1 x 1013 ohm.cm min (ASTM D257)
• Dielectric constant: 5 max
• Approval: POWERGRID manufacturer approval for insulation sleeves and tapes, valid to 17 Feb 2028
• Packing: Reels of 25 m or 20 m; 1.5 m lengths for GMB 205/85 and GMB 250/100

Sizes

• GMB 16/6 | D 16 / d 6 | T 1.70 | 25 m | rect W+B 11-18 | round 7-12
• GMB 25/10 | D 25 / d 10 | T 2.50 | 25 m | rect 16-30 | round 12-20
• GMB 30/12 | D 30 / d 12 | T 2.10 | 25 m | rect 25-38 | round 16-25
• GMB 40/16 | D 40 / d 16 | T 2.10 | 25 m | rect 33-50 | round 21-32
• GMB 50/20 | D 50 / d 20 | T 2.10 | 25 m | rect 38-63 | round 24-40
• GMB 65/25 | D 65 / d 25 | T 2.20 | 25 m | rect 53-82 | round 34-52
• GMB 75/28 | D 75 / d 28 | T 2.50 | 25 m | rect 63-94 | round 40-60
• GMB 85/32 | D 85 / d 32 | T 2.50 | 25 m | rect 69-107 | round 44-68
• GMB 100/38 | D 100 / d 38 | T 3.00 | 25 m | rect 83-126 | round 53-80
• GMB 120/45 | D 120 / d 45 | T 3.00 | 25 m | rect 104-150 | round 66-96
• GMB 150/60 | D 150 / d 60 | T 3.30 | 20 m | rect 132-200 | round 84-127
• GMB 180/72 | D 180 / d 72 | T 3.00 | 20 m | rect 151-226 | round 96-144
• GMB 205/85 | D 205 / d 85 | T 3.10 | 1.5 m length | rect 239-257 | round 152-164
• GMB 250/100 | D 250 / d 100 | T 3.10 | 1.5 m length | rect 264-314 | round 168-200

Applications: MV switchgear manufacturers, RMU and panel builders, bus duct makers, substations, power utilities, transformer and switchboard OEMs, industrial and infrastructure electrical contractors