Before you buy any line
Eighteen tests. Run them on ours too.
Grouped the way a buyer actually thinks: what it costs to run, whether the bar passes, and whether the line keeps going.
Drive readout · mid-runOne question before any of it: what are you building — a brand, or something to sell? Everything below gets stricter as the answer gets more ambitious.
Cost of production
01
Sustained speed at your largest diameterNot your smallest. Peak speed on a thin bar is marketing.
02
Power per kilogram producedAsk for the meter reading, not the connected load. Only one shows up on your bill.
03
Time from power-on to first saleable metreTime it yourself. Then multiply by two starts a day and 300 days.
04
Startup scrap, weighedIn kilograms, on a scale, in front of you. Not a verbal figure.
05
Diameter changeover timeYou will run several sizes. This is the one that quietly eats a month.
06
Steady-state scrap once the line settlesA different number from startup scrap, and the one that repeats every shift.
Quality
07
Tensile strength on bar from that runNot from a sample they brought with them.
08
Elastic modulus50–60 GPa, or under 40. Designers size to deflection, so this decides who can use your bar.
09
Diameter and weight per metre, 20 random barsWork out the variation. High variation becomes your rejection rate.
10
Cut length spread over 100 consecutive cutsRecord the spread, not the average.
11
Surface consistency across the runSand coating and helical wrap pitch, start to finish.
12
Third-party report against IS 18256On bar produced during that run, not a certificate from last year.
Uptime
13
Do the heaters hold above 250 °COr do they fade the moment you push them.
14
Pulling speed across diameters, and slippageAsk how often the rollers get replaced, and what that costs.
15
In sync, or every parameter set by handRecipe memory, or an operator rebuilding settings at each changeover.
16
Wear-part life in writingDie, puller pads, blades, heaters. In hours or metres, never “long life”.
17
Spares held where, delivered in how longAnd the service engineer’s name.
18
Does your supplier manufacture, or only sellWill they hand you a process, or a machine and good luck.