Description
Window Push Chain — P12.75 Pitch
Anti-sidebow chains at P12.75mm pitch push rigid, pull flexible — enabling compact electric and hydraulic window actuators to open large skylight, curtain wall, and louvre panels without the space requirement of hydraulic cylinders or rack-and-pinion mechanisms.
Product Overview: What Anti-Sidebow Chain Does
Anti-sidebow chains are a specialised variant of roller chain engineered to be rigid in compression (push mode) while remaining flexible during retraction into their storage magazine. A standard roller chain cannot push — under compressive load it simply buckles laterally. Anti-sidebow chains achieve push rigidity through a combination of closely fitted pin-bushing clearances that prevent lateral deflection under load, special link plate geometry that allows articulation in one plane (for magazine storage) while resisting it in the perpendicular plane (the push direction), and optional interlock features on the outer link plates that mechanically engage adjacent links under compression to form a temporarily rigid column.
The P12.75mm pitch version is the most common size for residential and light commercial window actuation systems. This pitch provides a practical balance between chain stiffness, drive sprocket size, and push force capacity. Electric actuators using this chain can typically generate 800–2,500N of push force at the window panel — sufficient for facade glazing panels up to approximately 1.2m² and for roof window vents up to 0.8m² depending on panel weight and wind load specification.
P12.75 anti-sidebow push chain for motorised window and skylight actuators
Specifications — P12.75 Anti-sidebow Chain
| Chain No. |
Pitch P (mm) |
Roller Ø (mm) |
Inner Width (mm) |
Pin Ø (mm) |
Pin Length (mm) |
Plate H (mm) |
Plate h (mm) |
Q min (kN) |
| P12.75SB |
12.75 |
— |
— |
— |
20.5 |
13.0 |
8.5 |
8.0 |
| P12.75SBF1 |
12.75 |
— |
— |
— |
20.5 |
13.0 |
8.5 |
10.0 |
F1 suffix indicates a variant with extended outer link plates providing a wider footprint for improved lateral stability on longer push strokes. Contact us for full dimensional drawings and magazine sizing data.
Key Engineering Features
The anti-sidebow chain’s push capability rests on four engineering elements working in combination. First, enlarged clearance between the inner and outer link plates in the lateral plane allows the chain to flex smoothly into a circular magazine during retraction, while the reduced clearance between pin and bushing in the push plane prevents lateral buckling under compressive load. Second, the link plate geometry incorporates a centering projection on the inner plate that engages a groove in the adjacent link under compression, mechanically preventing lateral offset at each link joint. Third, the pin material and surface treatment — typically hard chrome or zinc-nickel alloy — provides the corrosion resistance needed for outdoor facade and roof installation without affecting the close-clearance engagement geometry. Fourth, the minimum allowable curve radius of 250mm means the chain can be stored in a compact housing even at longer stroke lengths.
Applications
🪟
Flat Push Windows and Skylights
Single-leaf and two-leaf flat push windows driven by concealed electric actuators. The chain stores vertically in a slim housing behind the frame profile and extends to push the window open — a clean installation that suits contemporary architectural window systems.
🏗️
Curtain Wall Ventilation Panels
Large facade ventilation panels in commercial and institutional buildings. The push chain actuator is typically integrated into the structural transom or mullion of the curtain wall system, invisible from both inside and outside the facade.
🌬️
Louvre and HVAC Vent Panels
Automated louvre panels in HVAC systems, atria, and industrial ventilation facades. Push chain actuators allow precise positioning of louvre blades, enabling modulated ventilation control rather than simple open/close operation.
🏭
Industrial Roof Vents
Manufacturing facility roof ventilators driven by push chain actuators provide natural ventilation or smoke exhaust. The chain’s corrosion resistance is particularly relevant in these applications where ambient humidity and temperature cycling are extreme.
Surface Treatment and Corrosion Resistance
P12.75 anti-sidebow chains for outdoor facade and roof installations are supplied with zinc-nickel alloy surface treatment as standard — this coating provides substantially better corrosion resistance than standard zinc electroplating, with salt spray resistance exceeding 720 hours. For coastal locations or highly corrosive industrial atmospheres, stainless steel core variants are available with all functional steel components in 304 or 316 grade. The outer decorative link plates in facade-visible installations can be supplied with anodised aluminium facing for aesthetic integration with the surrounding window frame material.
Components and Matching Parts We Supply
◆
Drive Sprockets for P12.75 Anti-sidebow Chain
Precision-ground sprockets in the correct tooth form for P12.75SB chain engagement. Available in stainless steel and hardened carbon steel to match chain material specification.
◆
Chain Magazines and Storage Housings
Profiled aluminium chain storage magazines in standard lengths for P12.75 pitch chain. Curved magazine profiles in 250mm, 300mm, and 400mm bend radius for different installation geometry requirements.
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Drive Unit Mounting Brackets
Adjustable mounting bracket sets for integrating P12.75 push chain actuators into standard window frame profiles. Available in powder-coated aluminium to match standard RAL window frame colours.
◆
Connecting Links and End Fittings
Chain end attachment fittings in stainless steel for connecting the chain terminal to window panel pivot points or actuator rod ends.
Customer Reviews
★★★★★
“We specify P12.75SB for all our motorised skylight projects. The zinc-nickel treatment performs well in the Danish coastal climate — no corrosion complaints from any installation after 3 years. The chain dimensions are consistent batch to batch, which matters for our standardised actuator housing design.”
L
Lars Eriksen
Project Engineer — Copenhagen Facade Systems A/S
★★★★★
“Used P12.75SBF1 for a large atrium ventilation project — 120 push chain actuators on a north-facing curtain wall. The extended plate variant gave us the lateral stability we needed on the 450mm push stroke. Delivery was on schedule and the dimensional tolerances are tight enough for our precision actuator integration.”
M
Marco Gentile
Technical Director — Milan Window Systems SRL
★★★★★
“The technical data package — including dimensional drawings, surface treatment certificates, and minimum curve radius data — was complete and formatted for our client submission requirements. This level of documentation is not always available from chain suppliers in this niche product category.”
S
Sophie Laurent
Specification Engineer — Paris Architectural Hardware
Frequently Asked Questions
What is the maximum push stroke length achievable with P12.75 anti-sidebow chain?+
Maximum push stroke depends on chain column stiffness, which decreases as stroke length increases. For P12.75 chain with a 250mm minimum curve radius magazine, practical push strokes up to approximately 600mm are achievable without guide support. For longer strokes, a guide channel that supports the chain column laterally through the push zone extends this limit to 1,200mm or beyond. Contact us with your stroke length requirement and push force specification for a feasibility assessment.
Can P12.75 chain be used with any standard electric window actuator?+
P12.75 anti-sidebow chain is designed for actuators specifically built for this chain type — the drive sprocket tooth form, magazine profile, and actuator housing geometry must all match the chain’s dimensional specification. It is not interchangeable with generic roller chain actuators. Provide your actuator make and model when enquiring and we will confirm compatibility or recommend the correct chain variant.
What surface treatment is standard for facade-visible installations?+
Zinc-nickel alloy treatment is the standard for outdoor facade applications, providing 720+ hour salt spray resistance. For installations in areas of high visibility where chain appearance matters, anodised aluminium outer plate facing is available in silver, champagne, and RAL-matched powder coat finishes. Specify the RAL colour code of your window frame system when ordering.
Is P12.75 the same pitch as standard roller chain?+
No — P12.75mm is not a standard ISO or ANSI roller chain pitch. It is a proprietary pitch developed specifically for anti-sidebow push chain applications. P12.75 chains cannot be mixed with standard roller chains and require their own matched sprockets and housing components.
Do you supply the full actuator assembly or chain only?+
We supply the chain, matched sprockets, and storage magazines. Complete actuator motor and housing assemblies are not part of our standard supply range, but we can recommend compatible actuator suppliers whose products are dimensioned for our P12.75 push chain. Contact us with your project specification for referral details.
Get in Touch
Ready to Place Your Order?
Send us your chain specification and annual volume. Standard enquiries receive a quotation within 2 business days.
