Plough Disc Blades: 24–30 Inch Sizes, Weights and How to Order (Disco de Arado)

Plough disc blades do the hardest job on the farm: they cut, lift and turn the soil at full working depth. When they wear, the plough rides up, the furrow gets shallow and fuel use rises. This guide explains plough disc blade sizes, how they differ from harrow discs, and how to order the right replacement – also known as disco de arado in Spanish-speaking markets.

How Plough Disc Blades Differ from Harrow Discs

Both are round, concave steel blades, but they work in a different way:

• Size: disc ploughs normally use 24″ to 30″ blades; harrows use a wide range from 16″ to 36″.
• Concavity: plough blades have a deeper dish so they can lift and turn the furrow slice.
• Edge: plough blades are usually plain (smooth); notched blades are mainly used on harrow front gangs.
• Mounting: each plough disc runs on its own hub and bearing, fixed with bolts, while harrow discs share a gang shaft.

Because of the deeper dish and bolt pattern, a harrow disc of the same diameter usually cannot replace a plough blade. Always check concavity and bolt holes.

Plough Disc Blades on SH Ploughs: Sizes by Model

The table shows the disc sizes used on our disc ploughs:

Plough series	Discs	Disc diameter	Tractor power
Steel plate, small	2–4	460–510 mm	18–50 hp
Steel plate, 1SH-325 to 625	3–6	660 × 6 mm (26″)	50 to over 120 hp
Steel plate, 1SH-230 to 430	2–4	710 × 6 mm (28″)	35–90 hp
Round tube, 1SH-230 to 530	2–5	710 × 6 mm (28″)	40–120 hp
Little Fish	2–5	26, 28 or 30 in	40–120 hp
Paddy field (PTO)	3–9	560 mm	15–90 hp

Plough Disc Blades: Weight Guide

Weights from our disc blade table (plain blade) help you plan freight:

• 24″ (610 mm) × 6 mm – 14.67 kg
• 24″ (610 mm) × 7 mm – 17.12 kg
• 26″ (660 mm) × 6 mm – 17.6 kg
• 26″ (660 mm) × 8 mm – 23.4 kg
• 28″ (710 mm) × 6 mm – 20.8 kg
• 28″ (710 mm) × 8 mm – 27.73 kg

Our blades are made from 65Mn or 30MnB5 boron steel and heat-treated to HRC 38–44. Boron steel is the better choice for stony, sandy or very dry ground where blades wear fast.

How to Measure and Order a Replacement Plow Disc

1. Measure the diameter of an unworn blade, in inches or millimetres.
2. Measure the thickness near the centre.
3. Count the bolt holes and measure the bolt circle and centre hole.
4. Measure the concavity: lay a straight edge across the blade and measure the dish depth at the centre.
5. Note the plough brand or model, and send a photo if possible.

With these details we can match plow disc blades (US spelling) for most common ploughs, not only our own. We can also produce to your drawing.

When to Replace Disc Plough Blades

• The diameter has worn down by about 10–15 percent.
• The blade is cracked, chipped or bent.
• The plough no longer reaches its working depth even with correct setting.
• The hub bearing is loose – replace or repair it at the same time.

Keeping spare plough disc blades in stock makes disc plough replacement quick at the start of the season. Worn blades need more passes and more fuel, and timely field work is a point stressed in the FAO’s work on sustainable agricultural mechanization.

Disc Plough or Mouldboard?

Disc ploughs roll over stones and roots and work in hard, dry soil, which is why they are common in Africa, Latin America and Central Asia. For a full comparison read our disc plough vs mouldboard plough guide, and for tube-frame models see the tube disc plough guide.

Resumen en español: discos de arado para tractor

Fabricamos discos de arado lisos de 24 a 30 pulgadas en acero 65Mn o acero al boro 30MnB5, con dureza HRC 38–44. Los tamaños más usados en nuestros arados son 660 mm (26″) y 710 mm (28″) de 6 mm. Para pedir discos de arado para tractor, envíe el diámetro, el espesor, la concavidad, el número de agujeros y una foto del disco. También fabricamos arados de discos completos de 2 a 6 discos.

FAQ

What size are plough disc blades for a 3-disc plough?

Our larger 3-disc models use 660 mm (26″) or 710 mm (28″) blades of 6 mm; small 3-disc models for 18–40 hp tractors use 460–510 mm blades.

Can a harrow disc replace a plow disc?

Usually not. Plough blades have deeper concavity and a bolt pattern for an individual hub.

¿Venden discos de arado sueltos?

Sí. Vendemos discos de arado de repuesto sin el arado, en cantidades mixtas.

How long do plough disc blades last?

It depends on soil, speed and depth. Boron steel blades last longer in sandy and stony soil.

Get a Quote

Send the diameter, thickness, concavity, bolt pattern, steel grade, quantity and destination port on WhatsApp +86 133 8469 2372. See complete ploughs on our ploughs page and shipping options on the export page.