Ten years ago Walworth initiated a comprehensive Quality Assurance Program incorporating the requirements of API Q1 and culminating with the registration of our Inval Cast Steel and Plug Valve plant by QCB of Canada (Accredited by the Dutch Council) under the requirements of ISO 9001-1994; Certificate number 95-157. Walworth Valves are widely accepted by customers including Petroleos Mexicanos, Comisión Federal de Electricidad (CFE), Atlantic Richfield Inc., Consolidated Edison of New York, Chevron U.S.A., Exxon Company, Mobil Oil, Phillips Petroleum, Shell Oil, Texaco, and Union Carbide Chemical Co. to name but a few.

Walworth Valve Products are manufactured in accordance with internationally recognized and accepted standards including API, ANSI, ASME, MSS, NACE, AWWA, BSI, and CSA. At each of our five manufacturing facilities, a dedicated team of highly qualified engineers work to assure that each phase of the production process for each of our valve product lines meets or exceeds the customer´s specifications. CAD utilizing finite element analysis, fugitive emission qualification, and fire test capabilities are just a few of the in house resources helping to assure that our customers receive a valve product that meets and exceeds industry standards and customer expectations.

Since 1842, the Walworth name has stood for quality and dependability. Today, Walworth continues to serve the Petro-Chemical, Refining, Oil and Gas Production, Pipeline Transmission, Power Generation, Pulp and Paper, Waterworks and Commercial Construction industries around the world with a broad line of quality valve products in a wide array of materials and sizes. Walworth controls all aspects of production from material selection, radiographic verification of casting quality, dimensional control and final inspection and testing including critical component traceability.

Each of the ten product lines that Walworth produces has been designed and manufactured under a Quality Management System certified to meet ISO 9001 and API Q1 requirements. Our Cast Steel Gate, Globe and Check Valves; Forged Steel Gate, Globe and Check Valves; and Lubricated Plug Valves are produced at our Walworth-Inval facility in Mexico City, Mexico, while our Bronze and Iron Gate, Globe and Check Valves are produced at our Walworth-Fundival facility in Gomez Palacio, Mexico.

Ball Valves and Gate Valves for pipeline service along with upstream products such as wellheads, Christmas trees, chocks, and Valves are produced at our Walworth-FIP facility in Mexico City. This facility holds both the ISO 9001 certification and the API Q1 license to monogram products. Twelve years ago Walworth initiated a comprehensive Quality Assurance Program incorporating the requirements of the API Q1 Quality management System. Subsequently, Walworth expanded the system and each Walworth facility became certified to ISO 9001 requirements.

Walworth Gate Valves Design Features 1. Sure-grip Handwheel. Fluted design assures a firm grip, even with greasy gloves. 2. Yoke Nut. Extra long thread engagement between yoke nut and stem provides long thread life. Force feed lubricant application is included. 3. Gland Eye Bolts Facilitate Packing Maintenance. For ease in repacking the valve, gland eye bolts are mounted to swing aside. 4. Extra Clearances Prevent Stem Scoring. Sufficient clearance between the gland, stem and stuffing box prevents scoring stem even if the gland is inserted unevenly. 5. Deep Stuffing Boxes. Depth is more than adequate in all sizes and pressures to assure tightness and maximum packing life. Packing sizes conform to API requirements for refinery service. In all cases bonnet back seats are furnished against which the stem head may be seated, thus relieving the pressure on the packing to facilitate repacking. Stuffing box packing is a reinforced, flexible graphite packing which remains flexible and resilient at high temperature, which permits ease in gland adjustment, and which contains a corrosion inhibitor for protection of the stem. 6. Body-to-Bonnet Joint. A flat face gasket joint Is used In the Class 150 valve. A male and female or tongue and groove joint is used in the body - bonnet connection of the Class 300 and higher valves; this type of closure permits reassembly in the field without danger of misalignment. 7. Bodies of all valves give adequate bolt clearance for end flange bolting and for nuts between body neck and back of end flange. On Class 300 and higher valves, body-bonnet flanges are made circular for greatest strength and for minimum distortion. 8. Ports are Streamlined. Permits unobstructed flow which reduces turbulence resulting in minimum pressure drop and lowers erosion. 9. Integral Guide Rib Faces Assure Self-Centering of Wedge. All wedges of I-beam cross section for greater strength. Long guide slots in wedges making centering of wedges certain at all times. The wedge has integrally forged or cast heavy hooks to provide a substantial connection for the tee-head stem while allowing the wedge to center itself. 10. Seat Rings Designed to Eliminate Turbulence. Erosion and Pressure Drop. Cylindrical bottom-seated type having ample cross-section (for strength) are inserted so that no recess exists at the back of the ring. Seat ring and machined portion of body are finished accurately to gage. All Walworth Cast Steel Gate Valves can be furnished with either flanged ends or butt welding ends.	Click to Enlarge
Walworth Globe Valves Walworth Cast Steel Globe and Angle Valves have the same sturdy characteristics as Walworth Gate Valves, such as sure-grip handwheels, long threaded yokenuts, deep stuffing boxes, extra strong and tight bonnet joints, excellent guiding of discs above the seat for minimum restriction of flow, extra smooth seating surfaces for ease of tight seating, best selection of trim materials for varied services, etc. Walworth Cast Steel Globe and Angle Valves can be supplied with V-port, parabolic, or semi-parabolic discs for special flow characteristics. Where globe and angle valves in Class 300 and higher are regularly furnished with spur or bevel gearing, it will be of the enclosed type mounted, unless otherwise specified, with the handwheel shaft on the left side of the valve when facing the end port that leads from above the disc seat. When specified, these valves can be furnished without gearing.
Walworth Check Valves Walworth Cast Steel Swing Check Valves have straight-through flow paths and readily opening discs to provide very low friction loss. POINTS TO REMEMBER ABOUT CHECK VALVES 1. The function of check valves is to stop reversal of flow automatically and promptly. Usually it is desirable that they be supplemented by gate, globe, or other valves for manual control of the fluid in the line. 2 Check valves must be sized to meet the flow conditions. Oversizing of a check valve will result in increased wear and improper operation. 3. Check valves should be installed so that the force of gravity will assist in closing and holding the disc or clapper on the seats. 4. Check valves are one-way valves and should be installed so that the line pressure is under the disc. 5. Swing check valves should not be used in vertical pipe lines handling liquids at high heads because severe water hammer may result from reversal of flow.