Single-section: two straight stringers with fixed rungs — leans against structure at 65–75° angle; secured at top by hook or tie. Extension/telescopic: two sections slide over each other; upper section locks at any extension increment (every rung, 225–300 mm) using rung-lock hooks or cam locks. Folding A-frame: two single-section ladders hinged at the top apex — the hinge opens to a fixed-angle spreader bar to create a free-standing A-frame; closes flat for storage. Step stool: small A-frame with platform top instead of rungs — tool-free access step for operators, 200–600 mm height. Telescopic: compact stowage height — sections nest inside each other; each rung folds inward using a pivot mechanism; deployed height up to 4,000 mm from 650 mm stowed height.
Challenges
Stringer End Feet Slipping on Smooth Epoxy or Tiled Process Floors at Low Angle
Single-section ladder at 65–75° lean angle on smooth floor — rubber foot pad insufficient; ladder slips outward at base.
Extension Lock Failure (Rung Hook Disengages) Under Dynamic Loading on Extension Ladders
Vibration or shock during climbing causes extension lock hook to bounce off rung — sudden collapse of upper section.
A-Frame Hinge Corrosion in Wet Wash-Down Areas — Hinge Jams in Folded or Unfolded Position
SS hinge corrodes and seizes in A-frame apex — ladder cannot be opened or closed; stuck at one position.
Telescopic Rung Fold Mechanism Jamming from Product Contamination
Product (sticky fluid, powder) contaminates telescopic rung pivot — pivot jams; rung cannot fold for stowage or unfold for use.
Over-Extension of Extension Ladder (User Stands on Top Three Rungs — Centre of Gravity Too High)
Users stand on top rungs above safe working position — ladder unstable; tipping risk; strict rung marking required.
Solutions
- Serrated Anti-Slip Feet (Ø80 mm Base Pad with Serrated Edge) + Lashing Strap at Top: Large-area serrated rubber feet grip smooth floors; top lashing strap or hook secures ladder head to structure — prevents both base and top slip.
- Double Rung Lock (Primary Cam + Secondary Hook) on Each Extension Ladder Rung: Dual independent locking mechanism — both must disengage to allow collapse; vibration cannot disengage both simultaneously.
- PTFE-Lined Stainless Piano Hinge + Stainless Spreader Bar (Self-Locking Brace): PTFE-lined piano hinge resists corrosion and seizing — opens smoothly after 500 wash cycles; self-locking spreader prevents accidental fold.
- Food-Safe Stainless Telescopic Rung Pivot (No Cavity, Full-Penetration Joint): Solid pivot joint (no hollow cavity to trap product) in full-penetration weld — cleanable, no residue harbour point.
- Top-Rung Safety Marking (Red or Yellow Band on Top 3 Rungs) + Label "Do Not Stand Above This Rung": Colour-coded no-stand zone clearly visible from any position — prevents dangerous over-extension posture.
Applications
- Pharmaceutical / Food: Portable folding A-frame and step stools for occasional operator access to vessel heads, control panels, and high shelves in GMP areas.
- Maintenance: Extension ladders for overhead maintenance, pipe tracing inspection, cable tray access — carried by maintenance technicians.
- Tank Farms: Portable lean-to ladders for infrequent manual sampling and gauge reading on bulk storage tanks.
- Laboratory: Step stools for reagent shelf, fume hood, and centrifuge access — GMP finish; anti-slip feet.
- Warehouse: Folding A-frame and telescopic ladders for racking access, stock labelling, and overhead installation work.
Models & Capacities
| Portable, Folding & Telescopic Ladder — Models & Capacities | |||||||||||
| Model | Type | Stowed L×W [mm] | Working Height [mm] | Rung Width [mm] | Rung Section | Rung Centres [mm] | Max Load [kg] | Anti-Slip Feet | Top Lock Mechanism | Finish | Weight [kg] |
| POL-S-2M | Single-section lean-to | 200×400 | 2,000 | 400 | Ø25 round bar | 300 | 150 | Serrated rubber 80 mm | Hook/strap | 2B / brushed | 8 |
| POL-S-3M | Single-section lean-to | 200×400 | 3,000 | 400 | Ø25 round bar | 300 | 150 | Serrated rubber 80 mm | Hook/strap | 2B / brushed | 12 |
| POL-EX-4M | Extension (telescopic section) | 200×400 (base section) | Up to 4,000 | 400 | Ø25 round bar | 300 | 150 | Serrated rubber | Double cam lock | 2B / brushed | 16 |
| POL-EX-6M | Extension (telescopic section) | 200×400 | Up to 6,000 | 400 | Ø28 round bar | 300 | 150 | Serrated rubber | Double cam lock | 2B / brushed | 24 |
| POL-A-1.5 | Folding A-frame (self-standing) | 200×600 | 1,500 | 500 | Ø25 round bar | 300 | 150 | 4× rubber feet | Spreader bar self-lock | 2B / brushed | 10 |
| POL-A-2.5 | Folding A-frame (self-standing) | 200×600 | 2,500 | 500 | Ø25 round bar | 300 | 150 | 4× rubber feet | Spreader bar self-lock | 2B / brushed | 16 |
| POL-SS-400 | Step stool (platform top) | 200×400 | 400 platform ht | Platform 300×400 | Solid anti-slip plate | — | 150 | 4× non-slip rubber | Fixed spread | Ra<0.8 EP | 4 |
| POL-SS-600 | Step stool (2-step) | 200×500 | 600 platform ht | Platform 400×400 | Chequer plate + step | — | 150 | 4× non-slip rubber | Fixed spread | Ra<0.8 EP | 6 |
| POL-TC-4M | Telescopic (nesting rung-fold) | 650 stowed | Up to 4,000 | 380 | Fold-flat aluminium rung (SS version) | 300 | 150 | Non-slip rubber | Auto rung lock (cam) | Satin SS 304 | 9 |
| POL-GMP-A | GMP folding A-frame + platform top | 220×700 | 800 (2 step, platform) | 500 platform | Perf plate + 2 rungs | — | 200 | 4× chemical-resistant rubber | Quarter-turn pin lock | Ra<0.8 EP | 12 |