Conveyor chains require precise RFQ specifications for pitch and attachments

Export buyers sourcing roller and attachment chain systems need quotation requests that leave little room for interpretation. A basic inquiry that asks for a “standard chain with attachments” may receive several quotations, but those offers can describe different pitches, materials, attachment spacing, tensile ratings, lubrication options, or dimensional tolerances. The apparent lowest price may therefore not represent the same product configuration.

For late-stage sourcing teams, the purpose of a request for quotation is not only to obtain pricing. It is to establish a common technical basis so every supplier prices the same chain assembly, accessory layout, quantity, packaging requirement, and delivery condition. Well-prepared RFQs for Conveyor chains help purchasing teams compare offers more efficiently and reduce clarification cycles before purchase order release.

This guide explains how to specify pitch, attachments, dimensions, application conditions, inspection requirements, and commercial details for roller-based conveying systems. It is intended for buyers working with international manufacturers, distributors, engineering contractors, and maintenance procurement teams.

Why pitch is the foundation of a comparable quotation

Pitch is the center-to-center distance between adjacent chain pins or rollers. It is one of the most important dimensions in a chain RFQ because it influences sprocket compatibility, attachment positions, running speed, allowable articulation, and the overall length of the conveying line. A supplier cannot reliably quote an interchangeable replacement chain without a confirmed pitch.

Do not describe pitch only as “small,” “medium,” or “large.” State the dimension in millimeters and, where appropriate, inches. If the chain is intended to replace an existing assembly, provide the exact measured pitch together with the original manufacturer’s part number, chain series, or engineering drawing. Buyers should also state whether the quoted product must match an existing sprocket profile.

In many projects, a nominal pitch alone is insufficient. Similar chains may have matching pitch values but different roller diameters, plate heights, inner widths, pin diameters, or plate thicknesses. These differences can prevent fitment even when a sample appears visually similar. Therefore, an RFQ should identify the complete chain designation when known and list critical dimensions when it is not.

Dimensions to include with the pitch

• Pitch: Center-to-center distance between consecutive pins or rollers.
• Roller diameter: Essential for sprocket engagement and load transfer.
• Inside width: The width between inner plates or side plates.
• Pin diameter: Relevant to wear performance and tensile construction.
• Plate height and thickness: Important where guards, guides, or tight clearances are present.
• Overall width: Particularly important when attachments extend beyond the chain plates.
• Chain series or standard: For example, an applicable ISO, ANSI, British Standard, or manufacturer-specific designation.
• Hand of chain: State whether the layout is single strand, duplex, triplex, or another arrangement.

If the buyer has a physical sample, measurements should be taken from a clean, unloaded section. Wear can increase the apparent pitch of an old chain, so it is useful to report both the nominal designation, if available, and the measured value across several pitches. Measuring over multiple links can provide a clearer indication of elongation than measuring a single interval.

Where a new line is being designed rather than replaced, the procurement team should confirm the specified chain with the mechanical designer before requesting prices. Related equipment categories, including drive equipment and fabrication components, can be reviewed through the industrial machinery directory when building a broader sourcing list for a conveying project.

How to define attachments without ambiguity

Attachments convert a basic chain into a product-handling component. They may carry fixtures, flights, slats, trays, shelves, brackets, scrapers, pushers, hooks, or custom tooling. Because attachment configurations are highly application-specific, they should never be described solely by a general name such as “extended pin” or “plate attachment.”

A complete RFQ should identify the attachment style, location, spacing, orientation, dimensions, thickness, hole pattern, welding method, and tolerance requirements. If the attachment is custom fabricated, a dimensioned drawing is normally more reliable than a text description. Include revision numbers and dates on all drawings so suppliers quote against the same document.

Attachment information buyers should provide

1. Attachment type: Identify whether it is an A-type, K-type, M-type, extended pin, bent plate, welded bracket, scraper blade mount, custom flight support, or another defined configuration.
2. Attachment side: State whether attachments are fitted on one side, both sides, the inner side, outer side, top, bottom, or alternating positions.
3. Attachment interval: Specify the frequency clearly, such as every pitch, every second pitch, every third pitch, or at a custom repeating sequence.
4. Attachment dimensions: Provide length, width, thickness, bend angle, projection, hole size, center spacing, and edge details.
5. Hole specification: Include threaded or through-hole type, thread standard, countersink details, slot dimensions, and positional tolerances.
6. Material and finish: State whether the attachment must match the base chain material or use a separate grade, coating, or corrosion-resistant finish.
7. Welding requirements: Identify the required weld location, weld type, cosmetic limitations, and whether weld inspection is needed.

Attachment spacing is especially important. An RFQ that says “attachments every 100 mm” can be unclear if the stated pitch does not divide evenly into 100 mm. Instead, define spacing in chain pitches wherever possible. For example, “one attachment on every fourth pitch” is more directly connected to the chain construction and is easier for suppliers to verify.

If attachments must align with product stations, sensors, fixtures, or transfer points, include an assembly drawing showing the datum point. Clarify whether the first attachment location is measured from the chain end, connecting link, master link, or a designated reference pin. This prevents a correctly manufactured attachment interval from being installed with the wrong starting position.

Specify operating conditions before requesting a price

Dimensional compatibility alone does not establish whether a chain will perform in service. Buyers should provide operating data so suppliers can assess whether the requested construction is suitable for the load, speed, environment, and duty cycle. This is particularly important for systems with long operating hours, shock loading, frequent starts and stops, inclines, high temperatures, washdown exposure, or abrasive contamination.

The RFQ should identify the conveyed product, maximum unit load, total moving load, line speed, conveyor length, incline or decline angle, drive arrangement, number of sprockets, and expected operating hours. State whether loads are uniformly distributed or concentrated at certain positions. A chain that works in a lightly loaded horizontal application may not suit an accumulating, indexing, or inclined arrangement using the same nominal size.

Application and environment checklist

• Conveyed material or product description.
• Maximum product weight and total live load.
• Conveyor speed in meters per minute or equivalent units.
• Duty cycle, including shifts per day and estimated running hours.
• Horizontal, vertical, inclined, curved, or indexing conveyor arrangement.
• Start-stop frequency and expected shock loads.
• Operating temperature range.
• Exposure to moisture, steam, washdown, dust, chemicals, or abrasive materials.
• Lubrication method and restrictions on lubricant type.
• Noise, cleanliness, corrosion resistance, or food-contact requirements where applicable.

For chemically exposed applications, describe the actual media rather than writing only “corrosive environment.” Concentration, temperature, cleaning frequency, and exposure duration can affect material selection. Procurement teams evaluating the wider process environment may also consult relevant chemical industry suppliers when mapping compatible process materials and services.

Buyers should avoid specifying a chain based only on ultimate tensile strength. Breaking strength is not the same as recommended working load, fatigue resistance, wear life, or allowable load under a particular service factor. Ask each supplier to state the quoted chain’s rated working load, ultimate tensile strength, and any assumptions used in sizing. This creates a clearer technical comparison between offers.

Build the RFQ around drawings, tolerances, and inspection

For custom assemblies, the drawing package is often the most important part of the RFQ. Include a general arrangement drawing, detailed attachment drawing, bill of materials where available, and photographs of an existing chain if it is a replacement. Photographs are useful supporting evidence, but they should not replace controlled dimensions and technical notes.

Every drawing should show units, scale where useful, revision level, material notes, surface treatment, and critical inspection dimensions. Mark dimensions that are essential for installation, including sprocket engagement features, attachment hole centers, chain width, attachment projection, and overall assembly length.

Recommended quality requirements

Specify tolerances only where they are functionally necessary. Overly tight tolerances may increase cost and lead time without improving the performance of the conveyor. Conversely, leaving critical attachment-hole positions unspecified can result in installation problems. A useful approach is to mark critical-to-fit dimensions on the drawing and permit standard manufacturing tolerances on non-critical features.

When a custom attachment involves fabricated metal parts, buyers may also identify potential production partners through the steel and metal directory. This can be helpful when comparing chain suppliers with separate fabrication and assembly capabilities, although each quotation should still be assessed against the same controlled specification.

Commercial details that make supplier offers easier to compare

A technically complete RFQ also needs clear commercial instructions. State the requested quantity in chains, loops, meters, or complete assemblies, and identify the required cut lengths. If chains must be supplied as matched sets, specify the number of sets and whether each set requires equal length matching.

Ask suppliers to separate the unit price, tooling cost, engineering charge, sample cost, packaging cost, inspection cost, and freight terms when applicable. Separate pricing helps buyers understand whether a low initial quote depends on omitted services or one-time charges that will affect repeat orders.

Your RFQ should request the following commercial responses:

• Quoted currency and price validity period.
• Quantity breaks and minimum order quantity, if applicable.
• Tooling or setup charges for custom attachments.
• Sample availability and sample lead time.
• Production lead time after drawing approval or deposit.
• Packaging method, package weight, and package dimensions.
• Incoterm and named delivery location.
• Payment terms offered.
• Warranty terms, if offered by the supplier.
• Country of origin and export documentation availability, if required.

Do not assume that “complete chain” has the same meaning across suppliers. Confirm whether the price includes connecting links, master links, attachment hardware, lubrication, protective wrapping, corrosion protection, spare links, and identification labels. These small details can influence installation readiness and landed cost.

A practical RFQ template for roller and attachment chain sourcing

The following structure can be copied into a sourcing inquiry and expanded with drawings and photographs. It helps suppliers provide a technically aligned response while allowing the buyer to compare commercial terms on a consistent basis.

1. Project reference: Provide an internal RFQ number, product name, and drawing revision.
2. Chain identification: State standard series, chain size, strand arrangement, and manufacturer reference if replacing an existing item.
3. Key dimensions: List pitch, roller diameter, inside width, plate dimensions, pin diameter, and total length.
4. Attachment specification: Describe attachment type, material, side, orientation, frequency, spacing, hole pattern, and drawing reference.
5. Operating conditions: Provide load, speed, duty cycle, application layout, temperature, and environmental exposure.
6. Quantity requirement: Identify prototype, sample, initial order, and expected repeat-order quantities separately.
7. Quality documents: List required inspection reports, dimensional records, material information, and shipment photographs.
8. Packaging and logistics: State packaging expectations, labeling requirements, Incoterm, destination, and target delivery date.
9. Quotation format: Ask suppliers to state all assumptions, exclusions, lead times, payment terms, and price validity.

Before sending the request, conduct an internal review involving engineering, maintenance, quality, logistics, and purchasing. Engineering can confirm fit and function; maintenance can identify installation concerns; quality can define inspection points; and logistics can verify packaging and import requirements. This review is often faster than resolving technical gaps after multiple supplier quotations have arrived.

For sourcing teams seeking industrial supplier information across related categories, the supplier review resource can support broader market research alongside a controlled RFQ process.

Final checklist before releasing the RFQ

Before requesting supplier quotations, verify that the pitch is confirmed, all attachment locations are measurable, material requirements are stated, and the drawings show the correct revision. Confirm whether the application has special environmental conditions and whether the requested chain is a replacement part or a new design item. Most importantly, make sure every invited supplier receives the same technical files and commercial instructions.

A well-structured RFQ gives buyers a stronger basis for evaluating Conveyor chains on more than price. It enables a clearer review of fitment, attachment accuracy, documentation, production assumptions, packaging, and delivery terms. By defining pitch and attachment details at the start, export buyers can make supplier quotations more comparable and reduce avoidable uncertainty before placing an order.