40x52x6 mm HTCR Rotary Shaft Oil Seal NBR, Oil Return Helix Rubber-Covered Seal

Product Overview

A 40 x 52 x 6 mm HTCR oil seal is a small radial shaft seal for a 40 mm shaft in a 52 mm bore, the kind of position found on pumps, small gear cases and auxiliary drives. The lip is moulded with a return helix, a shallow spiral that carries oil back to the sump as the shaft turns, so mist and light seepage do not collect on the outside of the housing. The outer diameter is rubber covered and the body is 6 mm wide.

At a glance:

40x52x6 mm | NBR (nitrile butadiene rubber) | HTCR body, oil return helix on the lip, rubber-covered outer diameter, single lip with garter spring | made in Xingtai, Hebei, China | working range -30 C to +100 C (short peaks to +120 C)

VKEFOT builds this size in Xingtai, Hebei, China for engine rebuilders, parts wholesalers and repair shops working from measurements. The helix is directional, so the rotation direction of the shaft is part of the order information, together with shaft diameter, bore and seat depth.

Key Features & Benefits

• Oil return helix on the lip: The moulded spiral drives oil back toward the sump as the shaft turns, which keeps small, fast turning shafts from misting oil past the lip.
• Small 6 mm body: The thin profile fits shallow seats on compact housings, where a wider seal would stand proud or foul the shoulder.
• Rubber-covered outer diameter: The rubber jacket presses into the bore and takes up light scoring, so a housing that has already run a seal can usually be reused as it is.
• Spring-loaded lip: A garter spring keeps radial load on the shaft as the rubber beds in, so the seal keeps contact over its service interval.
• NBR for normal oil service: The nitrile element suits mineral oil and grease from -30 C to +100 C, with short peaks to +120 C, and stays flexible at low starting temperatures.
• Easy to stock and fit: The 40 x 52 x 6 dimension is checked directly against the shaft and bore, so a replacement is selected by measurement alone, without a special order.

Dimensions & Specification

Specification	Value
Inner Diameter (ID)	40 mm
Outer Diameter (OD)	52 mm
Width / Height	6 mm
Material	NBR (nitrile butadiene rubber)
Colour	Brown
Structure	Single lip, garter spring, moulded oil return helix on the lip, rubber-covered outer diameter, rotation direction sensitive
Seal Type	Rotary shaft oil seal
Marking	VKEFOT
Continuous Service Temperature	-30 C to +100 C (short peaks to +120 C)
Brand	VKEFOT
Origin	Xingtai, Hebei, China

Dimensions are nominal production values written as inner diameter x outer diameter x width. The oil return helix is directional, so the shaft rotation direction must be confirmed along with the three measurements before an order is released.

Material & Construction

The element is moulded from NBR (nitrile butadiene rubber) over a metal insert, with a rubber jacket covering the outer diameter. NBR handles mineral oil, gear oil and grease from -30 C to +100 C, with short peaks to +120 C, and keeps enough elasticity to follow small shaft runout. The lip carries a moulded return helix and is held on the shaft by a garter spring. Where the position runs hotter or carries synthetic oil, the same body can be quoted in FKM (fluoroelastomer), which holds continuous duty to about +200 C.

Quality Control and Inspection

• Incoming: compound hardness checked before release to production.
• In process: insert concentricity, lip geometry, helix form and direction, spring seating and jacket thickness checked at set intervals.
• Final: dimensional check on inner diameter, outer diameter and width, rubber hardness, direction check on the helix, lip edge inspection and marking, then packing count verification.
• Traceability: inspection results for each batch are recorded and kept; the inspection scope can be agreed before order confirmation.

Inspection records are kept by production batch and remain traceable from the delivered shipment. Third-party inspection before shipment can be arranged if it is requested with the enquiry.

Customization and OEM Service

packaging and logo available upon request

Packaging, Carton and Delivery

Standard packing is individual polybag, inner carton, then export carton. Carton marks, labels and barcodes are printed to buyer specification.

Lead time for standard sizes is typically 7 to 15 working days after order confirmation, and longer for sizes that are not held as standard stock. Minimum order quantity depends on whether the size is a stocked standard or made to order. Pricing, MOQ, freight and trade terms are confirmed in the written quotation. Send an RFQ with quantity and destination port.

How to Order

The more of this you include, the faster and more accurate the quotation:

1. Size or OE number: 40 x 52 x 6 mm, or the number stamped on your current seal.
2. Quantity and destination: required quantity, destination country and port.
3. Material requirement: NBR as standard, or FKM for higher temperature or synthetic lubricant.
4. Packaging requirement: carton marks, label data and barcode requirement.
5. Sample photo or drawing: where the seal is matched from a worn original.
6. Operating conditions: shaft rotation direction, oil temperature, lubricant type and shaft speed, if known.

Frequently Asked Questions

How do I confirm this seal fits my assembly?
Measure the shaft diameter, the housing bore and the seat depth, then compare the lip and body with the removed seal. Also confirm the direction the shaft turns, since the return helix is made for one direction.

What are the exact dimensions of this oil seal?
40 mm inner diameter, 52 mm outer diameter and 6 mm width. Confirm against your own sample or drawing, because housing depth and shoulder position differ between applications.

What is the minimum order quantity?
MOQ depends on whether the size is a stocked standard or made to order. State your required quantity and the MOQ and price steps are confirmed in the quotation.

What is the lead time, and can you ship by sea or air?
Standard sizes are normally produced and packed within 7 to 15 working days after confirmation. Sea and air shipments are both arranged; freight and transit time are quoted per destination.

Can you supply FKM or HNBR instead of NBR?
Yes. FKM or HNBR can be produced in the same geometry where continuous temperature or the fluid goes beyond the NBR range. Confirm the compound at the enquiry stage.

Do you provide samples, and are they free?
Samples for evaluation can be arranged. Sample and freight charges are quoted per request, and on a confirmed bulk order the sample cost is normally set off against the order value.

Does the helical return groove require a specific rotation direction?
Yes. The helix is moulded for one rotation direction, so give the shaft turning direction with the order. Installed against the rotation direction, it pumps oil outward and the position will weep.

Can you produce our packaging and logo?
packaging and logo available upon request.

Request a Quotation

Send the size or the number you are replacing, the shaft rotation direction, the quantity and the destination port, and we will reply with MOQ, lead time, packing details and price.

VKEFOT Seals: oil seals, O-rings and custom rubber parts. Xingtai, Hebei, China.