Quality Assurance & Warranty | Xiwang Machinery

Our Commitment

Warranty Policy

Clear terms, written into your quotation — not a verbal promise.

12M

12-Month Warranty

Screw barrels and screws are covered for 12 months against material and workmanship defects, provided the processed material stays within the corrosion and abrasion duty agreed at ordering.

FIX

Repair, Replace or Remake

If a fault is confirmed to be ours — material, machining or heat treatment — we repair, replace or remake the set at our cost. Faults caused by buyer-side operation or material outside the agreed specification are not covered.

DOC

Written Into Your Quotation

Warranty scope, alloy grade and inspection figures are stated on your quotation and shipping documents, so both sides know exactly what is promised.

How We Check

Inspection Workflow, From Raw Steel to Packing

01

Incoming Steel & MTC

Every bar arrives with a mill test certificate (grade 31CrMoV9 / 38CrMoAlA / bimetallic backing steel) and is checked against the order.

02

Spectrometer Verification

An XRF spectrometer reading is taken on every batch and matched to the grade — Cr, Mo, V, Ni percentages recorded before machining starts.

03

Machining Dimensions

OD, bore, flight profile and concentricity checked on the machine; fit clearances matched per set.

04

Hardness & Case Depth

Nitrided hardness HV 900–1020 and case depth 0.45–0.7 mm verified on every batch; bimetallic lining hardness HRC 55–72 checked on the bore.

05

Pressure & Leak Test

Vented and jacketed barrels are pressure-tested before shipment.

06

Packing Check

Rust protection, wooden case and marking checked against the packing list before the container is loaded.

Real Documents, Real Readings

Sample Certificates & Inspection Records

Samples from our routine orders, company names masked. Your shipment carries the full documents for your set.

Material quality certificate of 31CrMoV9 forged steel with chemical composition — Mill quality certificate — 31CrMoV9 forged blanks, full chemical composition and low-magnification structure test. Open full size →

Steel inspection certificate of 31CrMoV9 with ISO 9001 conformity note — Steel inspection certificate — 31CrMoV9 Ø155 forging, tensile and corrosion test items, ISO 9001 conformity. Open full size →

XRF spectrometer reading on a finished screw: Cr 2.46, Si 0.229, matching 31CrMoV9 — XRF spectrometer on a finished screw — Cr 2.46%, Si 0.229%, matching the 31CrMoV9 spec.

31CrMoV9 raw steel bars in stock, grade marked on each end — Raw 31CrMoV9 stock — every bar end-marked with grade and heat number for traceability.

Want the Inspection Report of Your Set?

We include the material certificate and hardness report with your shipment — and we are happy to share them before you order.

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