Industrial Parts

Cylinders, sensors and PLC cards off a retooled line:

most second-hand automation hardware comes from factories that changed product, not from machines that wore out. Costa Rica’s medical-device and precision plants run long rows of small pneumatic cylinders, valve islands and servo drives, with Festo, SMC, Allen-Bradley and Siemens on most of the labels, and a line rebuilt for a new product can release them by the dozen. The same parts keep a bottling line or a fruit packing plant running, which is where many of them get fitted again. All of it runs on compressed air, so the air compressor feeding it deserves a look at the same time.

Belt pulleys, belts, and gear motors on the mechanical side:

bearings and V-belts are the wear parts of any plant, from a sawmill to a feed mill, and they are bought by the number stamped on the race or printed on the back of the belt rather than by brand. Hydraulic cylinders, pumps and oil seals are bought the same way, whether they go on a workshop press or the three-point linkage of a farm tractor. Electric motors turn up either new or embobinado, rewound by a local shop after a burnout, and those are not the same purchase.

Matching a sensor, a valve coil or an air fitting to the machine:

three details stop a part that looks right from working. A proximity sensor has either a PNP or an NPN output, and it has to match the input card it wires into or the PLC never sees it switch. A solenoid valve’s coil is wound for one voltage, 24 volts DC on most modern panels and 110 AC on many older ones, so read the coil, not the valve body. Push-in fittings come in metric and inch tube sizes that look almost identical and leak when mixed. With PLC modules and servo drives, the family name is not enough: the series or revision on the label has to suit the CPU or the drive’s firmware.

A pulled cylinder or a rewound motor, checked before you pay:

ask whether the part is new in its box, pulled from a working line or simply untested, because those are three different offers for the same code. Parts from a clean assembly room often look unused, and looks prove nothing. Push a cylinder rod in and out by hand with the ports open: it should glide without catching, and a scored rod will chew through the new seal. Spin a balinera and feel for grit, and look for oil around the output shaft of a gear motor. On a rewound motor, ask who did the embobinado and when, and check that the original nameplate is still there; a rewind done badly costs efficiency and heat, so a shop tag with a date counts in its favour. On electronics, look at the pins and terminals for scorching or green corrosion, and ask to see the unit power up with its status lights before you hand over money.

A crate of surplus parts, listed so a technician can find it:

put the full part number in the text and a sharp photo of every label, because maintenance people search by code, not by description. Say plainly whether each piece is new in box, pulled working or untested, and give the coil voltage or output type where it applies. Split a mixed crate by family, cylinders in one listing and sensors in another, instead of one photo of a box. State how many of each you hold: a plant that standardised on one cylinder wants six of them, not one. A technician driving over from Grecia with a line stopped will want to see a cylinder stroke or a valve click, so have a regulator and a length of hose on the bench when they arrive.