Diamond Double Standard Chain Supplier in Kolkata & India — Allied Industrial Corporation

These chains are designed for use in mechanical power transmission systems.

A Double Standard Chain — also called a duplex roller chain, double strand chain, or 2-strand chain — is a power transmission and conveying chain built from two parallel single-strand roller chains joined side by side on common connecting pins. Unlike two separate simplex chains running on adjacent sprockets, a double standard chain is a single, factory-assembled unit where every inner plate, outer plate, roller, bushing, and pin is precision-aligned across both strands. The result is a chain that delivers approximately 1.8 times the load capacity of an equivalent simplex chain at the same pitch, while keeping the sprocket pitch circle diameter and centre distance unchanged.

At Allied Industrial Corporation, we are Kolkata-based suppliers with twelve years of deep experience in the Diamond Sprockets industry. We supply Diamond-grade Double Standard Chains to manufacturers, engineers, and procurement teams across West Bengal and all of India. When a drive is struggling under increased load — motor amperage creeping up, chain elongating faster than expected, sprocket teeth wearing unevenly — a double standard chain upgrade is frequently the most cost-effective fix available. It delivers dramatically more capacity without requiring a new sprocket diameter, a new centre distance, or a complete drive redesign. We help Indian industry make that upgrade correctly, the first time.

Why Upgrade to a Double Standard Chain?

The most common scenario we see at Allied Industrial Corporation is a machine that was originally designed around a simplex chain, where production demands have since increased — higher throughput, heavier loads, longer operating hours. Rather than redesigning the entire drive, the plant team rightly considers upgrading to a double standard chain. Here are the four situations where that upgrade is the right answer:

✓ Situation 1 — Load Exceeded
Your simplex chain is running near or above its safe working load. Elongation is rapid, sprocket wear is premature. Duplex doubles the load capacity at the same pitch — same sprocket diameter, same centre distance, no drive redesign.

✓ Situation 2 — Cannot Increase Pitch
A larger-pitch simplex chain would require larger sprockets that don't fit your frame. A double strand chain at the same pitch gives you 80% more load capacity with only a width increase — no diameter change needed.

✓ Situation 3 — Space Constraints
Moving to a triple strand chain is more than you need, but simplex is insufficient. Duplex lands exactly in the middle — the ideal step-up with minimum additional width.

✓ Situation 4 — Extended Service Intervals
A double strand chain at 60–70% of its rated capacity runs cooler, elongates slower, and lasts significantly longer than a simplex chain at 90%+ of capacity. Fewer replacements, lower maintenance cost.

If you are unsure whether your application needs a simplex roller chain, a double standard chain, or a triple strand roller chain, our Kolkata technical team will review your motor power, chain speed, sprocket data, and frame dimensions — and give you a definitive strand-count recommendation at no cost.

Double Chain Types & Full Specifications

Allied Industrial Corporation supplies the complete range of Double Standard Chains in ANSI, British Standard, and Diamond-grade specifications. Every duplex chain we supply can be matched to the correct diamond chain sprocket or industrial chain sprocket from our Kolkata inventory.

Chain Type	Standard	Designation	Best Application
Double Standard Roller Chain (ANSI)	ANSI B29.1	#35-2 to #120-2	American-standard machinery drives
British Standard Roller Double Strand Chain	BS/ISO 606	06B-2 to 24B-2	European machinery, Indian OEM
American Heavy Series Double Strand Chain	ANSI B29.1 H-Series	#40H-2 to #100H-2	Shock-load & heavy-duty drives
Industrial Double Strand Roller Chain	IS 2403 / ISO 606	Custom pitch range	General heavy-industry Indian plants
Diamond Industrial Double Strand Chain	IS 2403 / ANSI	Full Diamond range	Premium India-market specification
Stainless Steel Double Strand Chain	ISO 606 · AISI 304/316	08B-2 to 16B-2 SS	Food, pharma, chemical conveying
Double Pitch Double Strand Chain	ANSI B29.3	C2040-2 to C2080-2	Long-centre slow conveyor drives

Complete Product Specifications

All Double Standard Chains supplied by Allied Industrial Corporation are manufactured to IS 2403, ANSI B29.1, and ISO 606 standards with full material documentation available on request. The following parameters cover our standard Diamond duplex chain range:

Select the Right Duplex Chain Pitch

Duplex chain pitch selection follows the same logic as simplex — the pitch must match your sprocket exactly. However, when upgrading from simplex to duplex on an existing machine, verify that your current sprocket is already a duplex-bore sprocket, not a simplex sprocket with extended hub. Running a double strand chain on a simplex sprocket will contact only one strand's rollers, overloading that strand and causing rapid asymmetric wear.

Why Allied Industrial Corporation?

We are a Kolkata-based technical supplier with a stocked warehouse, a team that understands chain engineering, and direct manufacturer relationships that allow us to supply Diamond-grade Double Standard Chains at competitive pricing with short lead times. Here is what working with us means for your procurement:

Allied Industrial Corporation stocks the complete chain family to meet every drive requirement on a single invoice — from Diamond Simplex Roller Chain and Standard Roller Chain through Triple Strand Roller Chain, Heavy Duty Roller Chains, Diamond Engineering Class Chains and Industrial Conveyor Chain and Elevator Chain. One supplier. One point of technical accountability. One GST invoice.

FAQs — Double Standard Chain

Select the Right Duplex Chain Pitch

When upgrading from simplex to double standard chain, the pitch must remain the same as your existing drive — you are only changing from single to dual strand, not changing the pitch circle. Verify your existing chain's ANSI number or BS designation from the side plate stamp (e.g., "60" for ANSI #60, "12B" for BS 12B), confirm your sprocket is already a duplex-bore sprocket (two parallel rows of teeth), and order the "-2" variant of your current chain designation. If your sprocket is still simplex, you will also need a duplex sprocket — Allied Industrial Corporation supplies both, matched and verified.

What is the difference between a Double Standard Chain and a Double Pitch Chain?

These are two entirely different products. A Double Standard Chain is a two-strand (duplex) version of a standard-pitch roller chain — same pitch, twice the strands, approximately 1.8× the load capacity. A Double Pitch Roller Drive Chain is a single-strand chain with twice the pitch of the equivalent standard chain (e.g., C2040 has a 25.4 mm pitch compared to ANSI #40's 12.7 mm pitch). Double pitch chains are lighter and cheaper for slow, long-centre conveying applications. Double standard chains are for high-load drives where you need more capacity, not a longer pitch.

Is ANSI or British Standard double strand chain right for my machine?

The correct standard is determined by your machine's design origin. ANSI #-2 designations are used in machinery of American, Japanese, and South Korean origin. BS-2 designations (e.g., 12B-2) are used in European and older Indian-designed machinery. The two standards use the same pitch at equivalent chain numbers but differ in roller diameter and inner link dimensions — they are NOT interchangeable. Check the chain marking on your existing chain: if the side plate shows a number without a "B" suffix, it is ANSI. If it shows a "B" suffix, it is British Standard.

Do you supply K1 attachment double strand chains?

Yes. Allied Industrial Corporation supplies K1 Attachment Chains and Roller Chains With Attachment in duplex configurations. Double strand attachment chains are used in heavy-duty pusher conveyors, carrier conveyors, and indexing systems where a single-strand attachment chain has insufficient capacity. Specify your ANSI or BS pitch, the attachment type (K1 or K2), and the required chain length, and our Kolkata team will confirm stock availability and lead time.

What is the minimum order for B2C buyers in Kolkata?

Individual buyers and small workshops can purchase double standard chain from as little as 1 metre. We cut to your required length and supply with the correct duplex connecting links and split pins. There is no minimum order commitment for B2C purchases at our Kolkata facility. For B2B bulk orders of 50 metres or more, we offer volume pricing — contact us for a customised quotation. Annual rate contracts are available for large recurring requirements across India.

Why Buy Through Allied Industrial Corporation?

• Guaranteed Genuine
• Over 55+ Years of Trust
• Widest Stock
• Fast Delivery
• Complete B2B & B2C Documentation
• Technical Support