How to Choose a Block Making Machine

Start with the moulding cycle, not the motor size

The moulding cycle is the time from one discharge to the next. It is usually quoted in seconds, and small differences compound quickly: at a fixed number of operating hours, a 35-second cycle produces roughly 28% more blocks than a 45-second cycle on the same machine.

That is why two machines with almost identical frames can sit at very different outputs. When comparing quotations, put the cycle time next to the stated output per shift and check that they agree with the number of hours assumed. If a supplier quotes output without a cycle time, ask for it before comparing prices.

Read the output figure carefully

Output is normally quoted per shift and per product. Standard brick 240 × 53 × 115 mm and hollow block 390 × 190 × 190 mm are the two references in our own catalogue, and the difference between them is large — a machine that produces 15,000 standard bricks per shift typically produces around 2,400 hollow blocks in the same shift.

• Check which block profile the output figure refers to.
• Check whether the figure is per shift, per hour or per day, and convert it to a single unit.
• Ask how many cavities the quoted mould has — output scales with cavity count, not with machine size.
• Consider rework and downtime: real production is lower than theoretical output.

Match the drive to the power you actually have

Vibration motors need a stable supply. A 1.1 kW machine will run from a 220 V single-phase supply, while machines at 3.7 kW and above are normally specified for 380 V three-phase. If your site does not have a three-phase connection, the cost of bringing one in is part of the machine cost and should be factored into the decision.

Where there is no reliable grid, diesel-driven machines remove that dependency. You trade a lower output per shift for the ability to work anywhere, and you take on fuel, servicing and engine wear.

Mould configuration decides what you can sell

The machine ships with one mould box, and that mould decides which products you can produce. Additional profiles — hollow blocks, pavers, shaped blocks — are quoted as separate moulds, so the total cost of entering a product line includes the moulds, not just the machine.

If you intend to sell more than one block profile, work out the full mould list before you buy. Buying a larger machine with a single mould and then adding moulds later is a normal route, but the machine frame has to be capable of the cavity weight you plan to run.

• One machine = one installed mould at a time; plan the changeover time into your schedule.
• Multi-cavity moulds raise output but need a higher-power machine to vibrate the heavier load.
• Custom profiles can be made to your drawing — allow additional lead time for tooling.

Site conditions and shipping

Mobile machines are designed to be moved to the casting bed, which suits sites producing blocks at the point of use. Stationary machines with a charging hopper trade mobility for output and are normally installed in a fixed yard with a loader or conveyor feeding them.

Shipping matters as much as the machine. Machines travel in wooden cases sized for container loading, and larger units may need a 20 ft or 40 ft container to themselves. Ask for the packed dimensions and gross weight, not just the machine dimensions, before you calculate freight.

A short ordering checklist

• Cycle time, and the block profile the output figure refers to
• Installed power and the supply voltage you have on site
• Cavity count for each mould you intend to run
• Full mould list, including any custom profiles and their lead time
• Packed dimensions and gross weight for freight calculation
• Spare parts you will need in the first year: blades, vibration motors, mould boxes