The DKLDC is the metric solvent-weld variant in FIP's DIALOCK diaphragm valve range, designed for shutting off and regulating abrasive or dirty fluids in industrial plastic piping systems. The defining feature is the patented DIALOCK handwheel: over 300 lockable intermediate positions let operators set and hold a precise flow rate, with an optical position indicator visible through a transparent PVC cap. Internal metal parts — including AISI 316 stainless steel bonnet screws — are fully isolated from both the fluid and the external environment, making the valve suitable for corrosive chemical dosing, water treatment, and aggressive process fluids.

What makes the DIALOCK handwheel different from a standard manual valve?

A standard handwheel gives you open and close — and maybe a few intermediate positions if friction allows. The DIALOCK mechanism mechanically locks at over 300 discrete positions around the stroke, so the set point stays where you leave it regardless of vibration or line pressure fluctuations. Combined with the CDSA (Circular Diaphragm Sealing Angle) geometry that distributes shutter pressure evenly across the diaphragm face, the result is repeatable throttling accuracy that is unusual in a manual plastic valve.

Which body material should I choose?

The DKLDC is available in four thermoplastics, selected by chemical compatibility and temperature. PVC-U covers most aqueous and chemical services at lower cost. PVC-C extends the upper temperature limit. PP-H handles higher temperatures and offers better chemical resistance for aggressive acids and bases. PVDF delivers the widest chemical compatibility and highest temperature rating. Diaphragm elastomers — EPDM, FKM, or PTFE — are selected independently to match the process fluid.