NTN 7E-HMK2830C needle roller bearing

NTN 7E-HMK2830C belongs to needle roller bearing, part of our Bearings range. Tell us how many you need by WhatsApp or email and we'll get back to you promptly with a quote for 7E-HMK2830C and any equivalents.

When a shaft needs to carry radial load but there is hardly any room around it, the NTN HMK series is one of the options maintenance and design teams turn to. This is a needle roller and cage assembly that works without an inner ring, so the shaft itself becomes the raceway. MR Industrial Accessories LLC supplies the HMK series to customers throughout the United States and in several Latin American countries.

Reading the code is the fastest way to confirm you are looking at the right part. HMK marks the family, and the digits that follow give the shaft size and the width, both in millimeters. So 7E-HMK1215C is built around a 12 mm shaft with a 15 mm width, 7E-HMK2215C around a 22 mm shaft with a 15 mm width, 7E-HMK2530C around a 25 mm shaft with a 30 mm width, and 7E-HMK2830C around a 28 mm shaft with a 30 mm width. The C at the end points to a design variant inside the series.

Because there is no inner ring, the shaft surface has to do that job. Check its diameter and tolerance, its hardness and how fine the finish is; a shaft that is too soft or too rough will wear early and take the bearing with it. Grease or oil both work as lubrication, and the housing design is what seals the assembly. Alignment between shaft and support matters as well, since these bearings do not tolerate much angular misalignment.

The low cross-section is what makes this design useful. It lets a machine builder shrink the assembly and still handle radial load in a small space, which is why HMK bearings show up in automotive components, machine tools, transmission equipment, pumps, compressors and agricultural machinery, as well as in gearboxes, camshafts, hydraulic pumps and linear guide systems.

If you are replacing a part, HMK bearings can be matched with references from other makers that use the same dimensional nomenclature, the HK series among them. Tolerances and cage type should be checked before you swap anything, because small design differences can change how the bearing performs. Send us the part number you have from another brand and we will tell you which alternative fits.