Weco hammer union

Buyers must prioritize Figure Number (e.g., Fig 100, 602, 1502) which determines the pressure rating and application. Ensure the Cold Working Pressure (CWP) matches your operational requirements, ranging from 1,000 PSI to 20,000 PSI. Additionally, verify the connection type (Threaded or Butt Weld) and pipe schedule (e.g., Sch 80, Sch XXH) to ensure seamless integration with existing flowlines.

For applications involving H2S, you must specify Sour Service unions. These must comply with NACE MR0175/ISO 15156 standards. The materials used are typically forged alloy steel with specialized heat treatment to prevent Sulfide Stress Cracking (SSC). Look for olive green color-coding or specific 'Sour Gas' stamps on the wing nut and subs.

Reliable suppliers should hold API Spec 6A or 16C certifications. It is critical to request Material Test Reports (MTRs) that prove traceability to the original heat number. For international trade, ensure the products meet ISO 9001:2015 for quality management and have undergone hydrostatic testing at 1.5 times the rated CWP to guarantee safety.

The integrity of the primary metal-to-metal seal is paramount. For high-pressure models (Fig 602 and above), a replaceable rubber seal ring (Buna-N or Viton) acts as a secondary barrier to protect the metal seal against corrosion and erosion. Ensure the seal material is compatible with the fluid medium and temperature range of your project.

Always source from verified manufacturers on Made-in-China.com who offer Third-Party Inspection (TPI) services like SGS or BV. Request a pre-shipment pressure test video and photos of the heat number embossing. Avoid 'unbranded' high-pressure components, as failure in the field can lead to catastrophic safety incidents.

Focus on Total Cost of Ownership (TCO) rather than just the unit price. Negotiate based on volume tiers (e.g., 100+ vs 500+ pieces) and ask for spare seal rings to be included in the bulk price. Clarify the Incoterms clearly—FOB (Free On Board) is generally preferred for buyers with their own freight forwarders to maintain control over shipping costs.

Due to the high weight-to-volume ratio, sea freight is the most economical method. Ensure the supplier uses seaworthy packaging, such as reinforced wooden crates with anti-rust oil coating and VCI (Volatile Corrosion Inhibitor) bags to prevent oxidation during long transit times across humid maritime routes.

Utilize Trade Assurance or secure payment terms like Letter of Credit (L/C) or Telegraphic Transfer (T/T) with a deposit (typically 30%) and the balance paid against the Bill of Lading (B/L). This ensures the supplier is motivated to meet the agreed-upon quality and lead time before receiving full payment.