We produce carbon steel, alloy steel, stainless steel, and bronze materials.
Yes, we can provide a material report EN 10204 3.1 certificate after the valve is completed.
Yes, we have portable PMI machines.
Yes, we can prepare test bars during production upon customer request.
Customers should choose suitable materials and pressure ratings based on working conditions, but we are responsible for the specified material and pressure rating.
For corrosive environments, we offer Duplex Stainless Steel (F51/F53), Hastelloy, Alloy 20, and Monel. For low-temperature (cryogenic) service, LCB, LC1, LC2, LC3, and LF2 materials are available. All material selections are supported by full Mill Test Reports (MTR).
Our warranty is 12 months after the valves leave the factory.
During the warranty period, we will repair or replace defects caused by material or manufacturing issues, excluding man-made damage.
We can provide installation and operation manuals.
Standard in-stock check valves can be dispatched within 3–7 business days. Made-to-order or large-volume orders typically require 4–10 weeks depending on material, size, and specification. Contact us with your project schedule for a confirmed delivery estimate.
We support EXW, FOB, CIF, and DDP Incoterms with sea, air, or express delivery. Accepted payment methods include T/T (bank transfer) and L/C. Standard terms are 30% deposit on order confirmation, balance before shipment.
Yes. We regularly coordinate with SGS, Bureau Veritas (BV), TÜV, and Intertek for witness testing and pre-shipment inspection at our Wenzhou and Lishui facilities. Please specify your inspection requirements at time of order.
The design standards are BS 1868/API 6D for swing check valves, API 594 for wafer check valves, and API 602 for forged check valves.
Swing check valve, lift check valve, wafer check valve, lug type, axial flow/nozzle check valve, tilting check valve, etc.
Wafer check valves designed by API 594 can have metal-to-metal or soft sealing designs, but BS 1868/API 6D/API 602 valves are metal-sealed.
Yes, retainerless wafer check valves are more reliable, as they are less prone to leaks or part failures compared to standard versions.
Metal-sealed check valves meet API 598 standards, and soft-sealed check valves can achieve zero leakage.
A swing check valve uses a hinged disc that closes by gravity or backpressure — best suited for horizontal pipelines with low to moderate flow velocity. A dual plate wafer check valve features two spring-loaded half-discs that close rapidly before reverse flow builds, preventing water hammer and pipeline slam. It is more compact and suitable for both horizontal and vertical upward-flow installations.
Design standards: BS 1868/API 6D/API 594/API 602, Face-to-face: ASME B16.10, Pressure test: API 598/API 6D, etc.
Yes, we can customize check valves based on customer's specifications on the original valve body.
Soft-sealed wafer check valves can achieve zero leakage, while hard-sealed check valves meet Class D standards for leakage.
Yes, we have BS 1868-designed WCB swing check valves in stock, ranging from 150LB to 600LB in various sizes.
We produce check valves with pressure ratings from 150LB to 2500LB.
Yes, there is an MOQ limit for small sizes, but for larger sizes, 1 piece is acceptable.
Swing check valves can be installed either way, but lift check valves are recommended for horizontal installation.
Install wafer check valves with the flow direction matching the pipeline's flow, and in vertical pipelines.
A check valve prevents the backflow of media by using its disc, which moves based on pressure and weight.
Yes, after receiving the order, we can provide ITP (Inspection Test Plan).
Yes, we can provide mating flanges upon request.
Yes. Sedelon operates a global agent program offering competitive pricing, exclusive territory options, dedicated technical support, and co-branded marketing materials. Visit our [Agent Program page] or contact us directly to discuss partnership terms.
Yes. We offer OEM manufacturing with custom branding, packaging, and documentation. An NDA and minimum order requirement apply. Contact our sales team to discuss your OEM project requirements.
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