1. Product Introduction

The 6301-OPEN is a single-row deep groove ball bearing with the boundary dimensions 12 × 37 × 12 mm, supplied without seals and without shields. Rings and balls are made of high-purity GCr15 chrome bearing steel, through-hardened to HRC 60-62 and precision ground, so the bearing reaches P6 (ABEC-3) precision with Z3 noise and V3 vibration running quality. The open construction leaves the ball path completely exposed, which allows lubricating oil or grease to reach the raceways directly, keeps the internal friction at a minimum and lets heat leave the bearing quickly. This makes the 6301-OPEN the right choice for positions that are lubricated by oil circulation or oil mist and that run at continuous high speed, where a closed bearing would run hot and a contact seal would wear out. Standard ISO dimensions make it a direct drop-in replacement for bearings of the same size from any supplier.

2. Product Features

• Open structure, through lubrication: no seal or shield blocks the raceway, so oil mist and circulating oil reach the balls and grooves directly, the film stays stable and friction stays low.
• Fast heat dissipation: the open design lets air and oil carry frictional heat away from the rings, which keeps the temperature rise small during long high-speed runs.
• P6 precision grade: controlled bore, outside diameter and raceway roundness give a tight fit, low run-out and quiet rotation in precision assemblies.
• Z3 low noise, V3 low vibration: superfinished raceways matched with graded steel balls limit the excitation inside the bearing, so the running sound stays smooth and even.
• Radial and axial load in one bearing: the deep, uninterrupted groove carries radial load and moderate axial load in both directions at the same time.
• Simple inspection and relubrication: because the rolling elements stay visible, condition checks and grease replenishment can be done without dismantling the assembly.
• Standard interchangeability: the 12 × 37 × 12 mm envelope matches the international 6301 dimension series and fits existing shafts and housings directly.

3. Product Advantages

Each 6301-OPEN lot is checked for bore and outside diameter tolerance, raceway roundness, hardness, noise and vibration before packing, so the batch consistency stays stable from order to order. Because no seal is fitted, there is no seal drag and no seal wear, which means lower starting torque, lower running temperature and a longer working life in oil-lubricated circuits. Factory-direct supply covers P5 or P4 precision grades, selected radial clearance, matched ball grades, oil or grease lubrication and neutral packing on request, with the 6301 dimension held in stock for short lead times. For pump and spindle builders who control the lubrication on their own machine, this open bearing gives the highest speed capability and the best heat behaviour at the lowest cost per piece.

4. Product Technical Parameters

5. Product Applications

The most typical use of the 6301-OPEN is the coolant pump of a CNC lathe. In that position the bearing sits on the impeller shaft inside the pump body, where cutting coolant mixed with fine metal chips is always present and the pump runs for a whole shift at a time. An open bearing is the correct fit here: the pump is lubricated by its own oil circuit, the open raceway flushes loose particles out instead of trapping them behind a lip, and the free flow of liquid keeps the bearing cool while the shaft turns at speed. There is no rubber seal to swell in coolant and no shield to clog, so the pump keeps its flow rate and the bearing keeps its clearance over a long service interval.

Other positions where the same open bearing works well are oil-mist lubricated machine tool spindles, gearbox and headstock shafts with forced oil supply, hydraulic and lubrication pump shafts, small blowers with external oiling points, and any rotating assembly where the lubrication is filtered and monitored by the machine builder.

6. Company Profile

Ningbo Kent Bearing Company was established in 2003 and is one of the leading bearing manufacturers and exporters in China. Kent specializes in the design and production of high precision, high speed and low noise deep groove ball bearings and pillow block bearings. At present, the Corporation has more than 1,000 employees, a fixed assets of 2 billion yuan, and produces 250 million sets of bearings annually. The Corporation's products are widely used in more than 50 countries and regions under 2 independent brands, namely "BUGAO" and "NBKT".

Since 2003, the Corporation has set up a Research & Development Center equipped with multiple laboratories used for precision measurement, mechanical testing, lifespan testing, and physicochemical testing, to continuously upgrade its skills and raise its manufacturing standard and product's precision. Our workshops are installed with a series of advanced numerically-controlled, grinding and assembly equipment that utilize centralized filtration and cooling systems. Together with the production equipment suppliers, we developed these grinding, ultra-precision, fully automated integrated production lines, and own the intellectual property rights. The precision level of the products are at P5 level and above, with noise level reaching Z4, V4 and above. Some of our projects have exceeded the 30% precision reserves. Our products are widely used in electric motors, automobiles, motorcycles, household appliances, textile, electric tools and water pump equipment industries, both locally and globally.

The company has more than 20 assembly lines, and through ISO9001:2015 quality management system certification, has a professional technical and service team, technical personnel proportion of more than 30%. Over the years, we have been adhering to the use of high-end raw material production, from the first to every step, with excellent product development capabilities and strict quality control, we continue to expand the product line and application range.