(I) Sectional Door Specification
Standard Accessories
Thermal Insulation & Sealing
Door panels provide excellent thermal insulation. Thermal break + EPDM sealing strips are installed at panel connections to prevent water accumulation and cold bridging in cold storage applications. All four sides of the door are equipped with aging-resistant EPDM sealing strips to ensure full sealing when closed.
Manufacturing Process
Continuous high-pressure polyurethane (PU) injection foaming technology ensures tight bonding between the steel sheets and the foam core, with no voids in the insulation layer. The bond between the metal sheet and insulation layer is guaranteed not to separate for over 10 years.
Panel Material
Steel sheet: 0.4mm thick, pre-painted galvanized (alu-zinc) steel. Total panel thickness: 40mm.
Polyurethane Foam
Closed-cell rate > 95%. Uses 100% Tosoh (Japan) CFC-free, FCKW-free environmentally friendly PU material. Foam density ≥ 48 kg/m³. Thermal conductivity coefficient ≤ 0.033 W/(m²·K).
Wind Load Resistance
Door panel wind load resistance: 700 N/m².
Fire Rating
Fire rating for door in closed position: Class B (self-extinguishing).
Track / Guide Rail
Made of high-quality zinc-free galvanized steel sheet, thickness 2.0mm.
Torsion Spring System
Consists of 55CrSi torsion spring, steel shaft, cable drums, flanges, steel cable, center bracket, and connecting bolts. Balanced by a computer-designed torsion spring system. In case of power failure, the door can be operated manually via chain hoist with an operating force ≤ 20N.
Motor / Opener
Low noise operation during opening/closing. Equipped with manual release chain for power outage operation.
Control Box
Includes main power switch, emergency stop button, and three-button touch switch (up/stop/down). Features CPU fault indicator, digital operation cycle counter, protection class IP55.
Safety Device
Photosensor installed at the bottom sealing strip of the door to detect obstacles during movement, ensuring operational safety.
Spring Breakage Protection
Standard. Prevents the door panel from falling in case of spring breakage, protecting personnel and goods.
Cable Breakage Protection
Standard. Locks the door panel in place if the steel cable breaks, ensuring safety.
Cable Drum
Made of high-strength aluminum alloy for enhanced durability and long service life.
End Hinges
Made of hot-dip galvanized steel sheet, high strength, aesthetically pleasing.
Hinges
Galvanized for extended service life.
Bracket / Roller Carrier
Hot-dip galvanized steel sheet material, reinforced triangular design with flanged edges. Fully adjustable to ensure smooth door operation and tight closure against the track.
Steel Cable
12-strand full steel cable. Positioned inside the track for enhanced safety and longer service life.
Product Technical Data
Technical Description & Advantages
(1) Technical Description
Panel
The interior and exterior surfaces of the door panel are made of hot-dip galvanized aluminum-zinc high-quality steel sheet (0.45mm) from Baosteel, with an embossed texture. The surface is coated with two layers of fluorocarbon baking paint and one topcoat (including primer). Total panel thickness: 42mm. Thermal break rubber seals are installed between panel connections to prevent thermal transfer and reduce heat loss.
Foam
The door core is made of CFC-free polyurethane foam, injected under high pressure. Foam density: 48±2 kg/m³.
Seals
All sectional doors are equipped with top and bottom seals. Rubber seals are installed between the tracks and door panels to ensure good airtightness.
Side Seal: Installed on the fixed angle plate of the track, fitting tightly against the door panel after installation.
Bottom Seal: Industrial door-specific bottom seal, fully contacts the floor for excellent airtightness.
Top Seal: Professional top seal for industrial sectional doors. After installation, the seal presses tightly against the wall when the door is closed.
Insulation Value (unglazed panel):
For an installed door in the closed position (3 x 4m), the tested U-value is: 0.5 W/m²·°C.
The U-value between panels is: 0.43 W/m²·h·°C.
Tightness
Air permeability of the installed door: approx. 2.0 m³/m²/h (under 50 Pa pressure).
Wind Load
Standard wind load resistance: 700 N/m².
Lock
Standard doors are equipped with an internal spring latch. Unless otherwise specified, the latch is installed on the left-hand side of the door (viewed from inside).
Balancing System
Sectional doors are balanced by a high-strength spring system. Minimum spring service life: 30,000 cycles. Springs are low-stress, oil-tempered, torsion-type, spirally wound around a solid steel shaft. Material: 55CrSi.
Spring Breakage Protection Device
Each spring is equipped with a spring breakage protection device. In the event of spring failure, the door stops within 10 cm.
Cable Breakage Protection Device
Each door is equipped with a cable breakage protection device. If the steel cable breaks unexpectedly, this device clamps onto the side rail to prevent the door from falling.
Obstacle Detection Device
Applied to motor-operated doors. A wireless sensor is installed at the bottom seal of the door (avoiding the risk of damage common with wired sensors). It detects obstacles during movement to ensure safety.
Hardware
Hardware includes die-cast high-strength aluminum covers and 12-strand synthetic galvanized steel cables.
Galvanized hinges extend service life.
Aluminum curved brackets allow for easy continuous adjustment.
(2) Sectional Door Exploded View / Breakdown Diagram
No. Component
1 Vertical Rail
2 Support Angle for Rail
3 Horizontal Rail
4 Support Angle for Rail
5 Side Seal
6 Shaft
7 Shaft Connector
8 Shaft Bracket
9 Drum
10 Spring
11 Spring-break Prevention
12 SBR Spring Bracket
13 WS Spring Bracket
14 Door Opener
15 Door Opener Control Box
16 Bumper
17 Roller
18 Roller Bracket
19 Top Panel
20 Vision Window (Optional)
21 Central Panels
22 Hinge
23 Bottom Panel
24 Handle
25 Bottom Seal Slot
26 Bottom Seal
27 Bottom Roller
28 Steel Cord
29 Steel-Cord-Break Prevention
30 Bottom Cap
31 Breather (Optional)
32 Central Seal
33 Top Seal
34 Top Seal Rack
35 Top Seal Rack
36 Remote Controller Receiver (Optional)
