Description
Overview: Expanding Side Bow Chain Function with Attachments
A side bow chain without attachments transmits conveying force but carries no product directly. Attachment links add the functional interface between the moving chain and whatever the conveyor is transporting — hooks for hanging garments or meat products, pusher dogs for indexing boxes through process stations, flat cleats for supporting trays on inclined conveying, or custom carrier plates for proprietary product transport fixtures. The attachment link must satisfy two requirements simultaneously: it must have the same lateral flex capability as the main chain (so the attachment does not become a rigid point that resists the curve), and it must provide a sufficiently strong and precisely positioned mounting surface for the attached functional component.
SB series attachment links are designed with the same enlarged pin-bushing clearance as the main chain. This is the defining requirement — an attachment link with standard roller chain clearances would lock up the chain at the attachment position, forcing the surrounding links to carry the curve load that should be distributed across all links through the curve. In practice, a single rigid attachment link in a long curved section creates a concentration point for chain tension and guide rail wear that reduces chain service life significantly. Properly designed SB attachment links maintain full lateral flex through the attachment link position.
SB series attachment links — A-type, K-type, and custom forms for curved conveyor product handling
Attachment Types Available
Three standard attachment geometries cover the majority of SB chain conveyor applications. Custom forms are also available from customer drawings for proprietary carrier and fixture designs.
A1 and A2 Attachment Links
A-type attachments add a single tab projecting from one side of the outer link plate. A1 designates a tab with a single mounting hole; A2 has two mounting holes on the same tab. These are the most widely used attachment type for side bow chain conveyors — the asymmetric projection allows hooks, pins, and single-sided carriers to be mounted without bridging the chain centreline. A1 is sufficient for hanging applications; A2 is required when the carrier generates a torque load on the attachment point that a single bolt cannot resist.
K1 and K2 Attachment Links
K-type attachments project tabs from both sides of the outer link plate symmetrically — K1 with one hole per side, K2 with two holes per side. This bilateral configuration is required when the carried load must straddle the chain centreline, such as flat product carriers that extend equally to both sides of the chain run. K-type attachments also provide better resistance to lateral tipping loads when the product weight is not centred over the attachment point.
Custom Attachment Forms
Specialised applications often require attachment geometry that neither A-type nor K-type standard forms can accommodate. Common custom requests include: U-shaped hanging hooks for garment conveying; flat-top carrier plates with multiple bolt patterns for proprietary product trays; pin-type attachments for synchronised indexing systems where a pin on the chain engages a socket on the carrier; and angled cleat forms for inclined conveying of loose products on pitch-type conveyors.
Materials and Surface Treatments
| Material | Application | Corrosion Rating | Temperature Range | Food Contact |
|---|---|---|---|---|
| Carbon Steel — Untreated | Dry indoor conveyors, light industrial | Low (suitable for clean indoor only) | −20 to +120°C | No |
| Zinc-Nickel Treated | Outdoor and humid indoor environments | High (500+ hr salt spray) | −20 to +150°C | No |
| 304 Stainless | General food processing, dairy, bakery | Very High | −40 to +300°C | Incidental contact (check application) |
| 316L Stainless | Seafood, chlorinated wash-down, coastal | Excellent | −60 to +400°C | Yes — FDA / EU compliant |
Attachment Link Specifications — Key Dimensions
Attachment link dimensions vary by chain size (40SB through 80SB) and attachment type. The following representative data covers 60SB in A1 and K1 configuration — the most commonly ordered combination for mid-size overhead conveyor systems.
| Base Chain | Att. Type | Tab Width (mm) | Tab Height (mm) | Hole Ø (mm) | Bolt Size | Att. Interval | Max Hang Load (kg) |
|---|---|---|---|---|---|---|---|
| 40SB | A1 | 18 | 20 | 5.5 | M5 | 1–4 pitches | 8 |
| 40SB | K1 | 18 (each side) | 20 | 5.5 | M5 | 1–4 pitches | 6 |
| 50SB | A1 | 22 | 25 | 6.5 | M6 | 1–4 pitches | 12 |
| 60SB | A1 | 28 | 30 | 8.5 | M8 | 1–4 pitches | 20 |
| 60SB | K1 | 28 (each side) | 30 | 8.5 | M8 | 1–4 pitches | 16 |
| 80SB | A1 | 35 | 38 | 10.5 | M10 | 1–4 pitches | 35 |
| 80SB | K2 | 35 (each side) | 38 | 10.5 | M10 | 1–4 pitches | 28 |
Ordering Attachment Links
Attachment links are supplied separately from the main chain and assembled at specified intervals during installation. The standard order specifies: base chain number (e.g. 60SB), attachment type (A1, A2, K1, K2, or custom), attachment interval in pitches (minimum 1, maximum unlimited), number of attachment links required, and material or surface treatment. For custom attachment forms, supply a dimensional drawing or sample attachment link for quotation.
Pre-assembled chains with attachment links installed at specified intervals are available as a complete supply — send your chain length, attachment type, and interval and we will supply the assembly ready for installation. Pre-assembly reduces installation time and eliminates the risk of installing attachments at incorrect pitch intervals, which causes carrier spacing errors that can disrupt downstream processes.
Components and Matching Accessories
Customer Reviews
“We design overhead conveyor systems for garment factories and automotive trim plants. 60SB with A1 stainless attachments is our standard specification for food and apparel applications. The attachment tabs are precisely formed and the hole positions are consistent across batches — essential for our standardised carrier hook design. Technical support helped us select the correct attachment interval for our carrier spacing requirement.”
“Specified 40SB K1 in 316L stainless for our cured fish hanging conveyor. The double-sided K1 attachment supports our hanging racks symmetrically, which prevents the swinging and misalignment we had with our previous single-sided arrangement. After 12 months in daily CIP wash-down conditions, the chains and attachments show no corrosion.”
“We ordered 60SB with A2 attachments for our overhead evisceration conveyor. The pre-assembled chain with attachments at the correct intervals saved significant installation time on our tight project schedule. The engineering team here confirmed the attachment interval calculation before production — appreciated the attention to detail on what could easily be a straightforward catalogue order.”
Frequently Asked Questions
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.
For background on side bow chain see our guide to roller chain components and their function.
