What Has To Be Ready Before The Machine Arrives

The most common cause of a delayed commissioning is not the machine. It is a supply that was never what the quotation assumed: a three-phase feed that sags when the compressor starts, an air line that delivers four bar of wet air, or a floor that turns out to be the only level place in the building and is also the walkway.

A machine that arrives into a site which is ready takes days to commission. The same machine into a site that is not ready takes weeks, and the weeks are usually blamed on the machine.

Two machines in position in a customer plant in Vietnam, on a marked floor, with the air and power brought to them. Getting to this photograph is mostly the buyer's work.

Electricity first, because it is the one that is hardest to fix afterwards. What matters is voltage, frequency, number of phases, cable size, breaker rating and earthing, and all six of them are decided before the machine is ordered. A machine built for a 50 Hz supply does not simply run slower on 60 Hz; the control timing changes with it. A nominal 380 V that measures 340 V under load will pull the current up and the weld down, and the electrician who sized the cable from the nameplate will not be there when the welds are cold.

Air second. Pressure is the number everybody checks and the least interesting: what matters is flow at pressure, and dew point. Wet air destroys valves and cylinders quietly over months, and the filter-regulator on the machine conditions air rather than drying it. If the plant has no dryer, the machine will eventually be blamed for a plant problem.

Water third, for anything water-cooled. Flow and temperature, not tonnage, and the chiller has to reject its heat somewhere: a chiller standing against a wall in a closed room heats the room, and the room heats the machine. Water hardness matters as well, because scale in a tip channel turns an electrode into a fuse.

Floor last, and least regarded. Level within a few millimetres over the machine's footprint, able to take the point load, anchored if the machine develops force, and with enough clear space to get a pallet truck or a hand crane to the loading side. We have seen a machine commissioned in a corner so tight that the fixture could not be changed without dismantling the guard.

The air preparation unit on one of our machines: filter, regulator, gauge and a manual valve. It conditions air; it does not dry it, which is a distinction that costs buyers cylinders.

A spot welder is heavy and its weight is not evenly distributed. The forklift capacity that matters is at the mast with the load at the distance it will actually be carried, not the number painted on the counterweight; and the container floor to dock height, the door width, and whether a truck can reach the door at all are questions worth answering before the vessel sails rather than after it berths.

A customer ordered a machine for a plant whose quotation said "380 V". We built for 50 Hz, shipped, and the machine arrived at a site running on 60 Hz. Nothing failed. The welds were simply cold, because the controller was timing a half-cycle that no longer existed, and the operator spent two days adjusting a schedule that could not be adjusted into correctness.

We air-freighted a control board and reprogrammed it, and the customer lost four days of production. The fault was in our quotation form, which had a line for voltage and no line for frequency. It now asks for voltage, frequency, phases, cable size, breaker and earth, and, where the customer already runs a welder, for a photograph of its nameplate — which settles most of the argument in one image.

A site sheet, so that the work at the other end can start before the machine lands: footprint and weight, lifting points and the centre of gravity, electrical data, air consumption at pressure, water flow and temperature if the machine is water-cooled, and the clearances needed for the fixture and for maintenance access.

Along with it, a request for two photographs: where the machine is going to stand, and the supply it is going to be connected to. Buyers send them more often than you would expect, and they have saved more than one shipment.

There is a cost to being early as well, and it is worth naming. A machine that arrives before the site is ready sits in a warehouse or in the middle of the floor, in its case, with the warranty running and nobody able to run it off. We would rather hold a machine a fortnight at our end, where it is still under our control, than have a buyer paying storage for a machine that cannot be switched on.

Commercial invoice, packing list with weights and dimensions, bill of lading, certificate of origin and the insurance certificate. The tariff code is worth confirming with the buyer's broker early, because a wrong code is a customs problem at the destination and nobody at our end can fix it from here.

A short list, and the same one every time, which is exactly why it is worth writing down once and reusing.

• Confirm the supply: voltage, frequency, phases, cable, breaker and earth, in writing.
• Confirm the air: pressure, flow and whether the plant has a dryer.
• Confirm the water for anything cooled, including hardness and where the chiller stands.
• Confirm the floor: level, point load, anchoring and access for unloading.
• Name the person on site who will sign the commissioning sheet, and the date the machine is expected.

That last item is not administrative. On the day, our engineer records the supply voltage measured under load, the air pressure at the machine, the water flow where it applies, the schedule as left, and a coupon welded and kept. Two signatures go on it. It is the document the warranty is judged against, and the one that settles the question of whether the machine was commissioned into conditions it was specified for.

None of these are welding subjects, and every one of them shows up as a welding problem on the day the machine is switched on.

PDKJ continues to provide customized laser welding and resistance welding solutions based on different materials, workpiece structures, welding requirements, and production applications.

• Spot Welding Machines
• Customized Welding Machine

Machines on our assembly floor. Every one of them leaves with an electrical data sheet, because the supply at the other end is never exactly what the quotation assumed.

Send us your part drawing or a sample, and our engineers will run a welding feasibility trial on your own material and recommend the equipment configured for your application.