EHRZ, the innovative YAMAWA roll tap for steel up to 40 HRC hardness

At its debut at MACH 2026, the Japanese company Yamawa has introduced the EHRZ tap to the European users, its brand-new machine roll tap that sets new application standards in threading of medium-hard steel. The tap is the optimal tool for all machining tasks that require more precise threads and higher surface finish overcoming the limitations of chip evacuation. Roll taps (also known as form taps), in fact, create internal threads by cold-forming or plastically deforming ductile materials rather than cutting them, resulting in no chips, stronger threads, and faster, higher-quality production. They work by using specialized, fluteless lobes to push the metal into the thread shape.

Z-PRO taps: specialized solutions engineered for the most demanding machining environments

The Yamawa EHRZ tap is part of the Z-PRO Series of high-performance taps introduced by the company a few years ago with the launch of the VU Series, initially featuring spiral pointed taps for through holes (VUPO) and spiral fluted taps for blind holes (VUSP). These taps are specifically designed for use in modern machining centers with either oil or emulsion; thanks to their technical features, VU taps ensure maximum performance, high quality, and manufacturing flexibility. Following the success of VU series, Yamawa has broadened the VU Series by adding new types such as the VUSP CH coated spiral fluted taps with axial coolant holes, the VUSP 1.5P with short chamfer, and added VUPO and VUSP taps with oversized classes: ISO3X(6GX), 7GX, ISO2X(6HX)+100.

Building on the success of the VU Series, Yamawa portfolio has expanded in years to include specialized solutions engineered for the most demanding machining environments such as the HV Series with superior chip ejection and stable tapping in heavy industry applications, the MH Series, the GGST tap (high-wear applications on cast iron and abrasive materials), PM “Red Ring” tap, the “must have” tap in the mold and die industry, developed for tapping hardened steel up to 45 HRC.

Field tests assess the superior performance of EHRZ taps

As mentioned above, the latest addition to the Z-PRO Series is the EHRZ high performance roll tap, developed for precision processing of steel up to 40 HRC and stainless steel. Field tests show clearly the effectiveness of Yamawa’s new tap; let’s take as an example the tapping of 42CrMo4 hardened steel (40 HRC hardness) with an ISO2X(6HX) M6x1 2P EHRZ tap. The measured torque was much lower than that of a conventional M6x1 tap in the same tapping conditions. Whereas in the conventional products wear shows after 900 holes, the innovative EHRZ tap can still work after 1600 tapped holes.

Technical highlights of Yamawa EHRZ roll tap

The combination of a unique thread relief and a coating that maximizes the benefits of surface treatment ensure torque reduction and improved welding-resistance. As a consequence, torque is significantly reduced, allowing for longer tool life and more precise threads.

EHRZ features wider flutes that allow for greater lubricant supply, resulting in improved lubricity and cooling abilities; the overall wear resistance is enhanced. Thanks to optimized substrate material in combination with a special coating developed by Yamawa, this innovative tap shows extraordinary performances on medium-hard steels up to 40 HRC as well as stainless steels. EHRZ is available with metric threads M3÷M16 and metric-fine threads MF8x1÷MF16x1.5; all details on the range can be found in the brochure available on Yamawa Europe’s website at https://www.yamawa.eu/downloads/