16 questions buyers ask before ordering

Yes. We accept sample orders of 20–50 kg, so you can check diameter, surface and hardness before a full order. Sample bars are charged, and the sample fee is refunded when you place a formal order; freight is paid by the buyer.

Yes, on the packing. We can print your brand on the packing; the bars themselves are not printed. Send your artwork with the order.

Yes. We are a manufacturer with a production site of about 6,000 m² in Wujin, Changzhou, Jiangsu, China (factory: No. 103 Huangyanqiao, Xueyan Town, Wujin District, Changzhou, Jiangsu, China). Cold drawing, peeling, straightening, induction heat treatment, centerless grinding, polishing and CNC cutting are done in-house; hard chrome plating and machining are done by long-term partner plants to our specification. Intertek assessed our production and trading on site in June 2026. Factory visits and video walk-throughs are welcome by appointment.

Our workshop runs 12 centerless grinders (10 × type 80, 2 × type 83), 4 induction lines (2 Q&T, 2 hardening), 6 polishing machines and 8 CNC saws, plus a combined drawing machine, a peeling machine, 2 cross-roll straightening machines and 2 point straightening presses. Diameters Ø4–140 mm are kept in stock, and up to Ø200 mm are made to order. Tell us the quantity and schedule; we confirm the delivery date in the quotation.

Cut-to-length from stock: 3–5 days. Non-standard diameters: 7–10 days. Custom heat treatment: 10–20 days. 42CrMo: 7–10 days. Sea-freight booking time is added, and the exact date is confirmed in the quotation.

1 t per order. Sample orders of 20–50 kg are available to check the bar before a full order.

T/T: 50% deposit with the order, and the balance before shipment.

Finished bars are wrapped in protective film and tied with cotton rope. We do not use steel straps on finished bars, because they can mark the surface. Export orders are packed in wooden cases or on wooden pallets.

Commercial invoice, packing list and the steel mill certificate for each heat, forwarded unaltered. A certificate of origin is arranged per order, and third-party inspection can be arranged on request.

In-house we check diameter with Mitutoyo micrometers, chrome thickness with a coating thickness gauge, hardness with a Rockwell tester and grade with a spectrometer. Ultrasonic flaw detection, metallography and salt-spray testing are done by accredited third-party laboratories when an order requires them. Laboratory reports from July 2026 on our sample bars are on our Quality page; the results apply to the samples tested.

Grade 45 is made to GB/T 699-2015; 40Cr and 42CrMo to GB/T 3077-2015. C45, S45C and SAE 1045; 41Cr4 and SCr440; 42CrMo4 and SCM440 are comparable grades for reference only — the chemistry ranges differ. The steel mill certificate for each heat is forwarded unaltered, and if your order requires a specific foreign standard, state it in the RFQ so we can check the heat analysis first.

Hard chrome is 10–50 μm per side, chosen per order, with chrome hardness up to HV800+. Salt-spray performance is not part of the standard specification; where a rating is required, we specify a thicker chrome layer and can have the order tested by a third-party laboratory.

Ø4–11 mm: −0.02/−0.05 mm. From Ø12 mm: 0/−0.02, −0.01/−0.03 or −0.02/−0.05 mm. Linear shafts are usually supplied at 0/−0.02 mm. If your drawing gives an ISO fit (for example f7), state it in the RFQ and we confirm the matching band. Straightness is about 0.1 mm/m from Ø25 and 0.2 mm/m below; roughness is Ra ≤ 0.4 μm on chrome and Ra ≤ 0.8 μm on ground bars.

Full bars come in 4 m, 6 m, 7.5 m or 8.1 m lengths. We CNC saw cut to length from 200 mm with about 3 mm allowance; the ends are left as sawn. End machining (threads, chamfers, centre holes) is done by long-term partner plants to our specification and assessed from your drawing.

FOB Shanghai or FOB Ningbo, China.

An induction-hardened rod (case ≥ HRC55, about 2 mm deep) puts the hardness at the surface, under the chrome, for wear and guidance. A Q&T rod (grade 45, 40Cr or 42CrMo) gives a stronger, tougher base for loaded rods and leaves the ends easier to machine. Send the rod drawing with load, stroke and working conditions, and we suggest a route in the quotation.