Mortise lock

When sourcing mortise locks, the most critical technical factor is the Backset (usually 60mm or 70mm) and the Center-to-Center distance, which must match your door preparation. You should prioritize locks made of 304 Stainless Steel or Solid Brass for the latch and bolt to ensure corrosion resistance. For high-traffic commercial areas, ensure the lock is rated for Grade 1 (1,000,000 cycles) according to ANSI/BHMA A156.13 standards to guarantee long-term mechanical durability.

Compliance varies by destination: for the North American market, UL 10C (3-hour fire rating) is essential for fire door assemblies. For the European market, look for the CE marking and EN 12209 certification, which classifies the lock's suitability for use on fire/smoke doors. Always request Material Test Reports (MTR) to verify that the alloy composition meets the advertised grade, preventing premature failure in humid or coastal environments.

The security of a mortise lock is heavily dependent on the cylinder. Look for Anti-drill pins made of hardened steel and Anti-pick telescopic pin technology. If the project requires high security, specify Restricted Keyways to prevent unauthorized key duplication. Additionally, check if the lock body features a Deadlocking plunger (Auxiliary latch), which prevents 'shimming' or 'loiding' the latch with a credit card when the door is closed.

It is vital to match the lock function to the usage scenario. Entrance functions allow the outside lever to be locked/unlocked by a key or thumbturn. Classroom functions ensure the outside lever can only be locked or unlocked by a key, preventing students from locking the door from the inside. Storeroom functions keep the outside lever always fixed; a key is required to retract the latch every time, ensuring the room is always secured upon closing.

To avoid 'zinc alloy disguised as stainless steel,' you should request a pre-shipment Salt Spray Test (usually 48-96 hours) report. For large orders, hire a third-party inspector to perform a PMI (Positive Material Identification) test using an XRF analyzer at the factory. Sourcing through reputable suppliers on Made-in-China.com allows you to check for 'Audited Suppliers' who have undergone verified on-site inspections.

Focus your negotiation on the weight of the lock body and the thickness of the faceplate, as these are where factories often cut costs. Request a tiered pricing model based on the finish (e.g., PVD Gold vs. Satin Stainless Steel). For bulk orders, negotiate for 1-2% spare parts (cylinders and springs) to be included at no extra cost, which covers minor maintenance needs without requiring new international shipments.

Mortise locks are dense and heavy; ensure the supplier uses double-walled corrugated export cartons and reinforced plastic strapping. Each lock should be individually boxed with molded foam or thick cardboard inserts to prevent the finish from scratching during transit. For sea freight, insist on desiccant silica gel packs inside every inner box to prevent oxidation or 'white rust' caused by moisture in the shipping container.

Always use Secured Payment terms provided by platforms like Made-in-China.com, which hold the funds until you confirm the goods have been shipped according to the contract. Avoid 100% upfront payments; a standard 30% deposit and 70% balance against the Bill of Lading (B/L) is the industry norm for established B2B relationships.