Grease removal

With the all-inclusive analysis kits from OELCHECK and our basic equipment, you are perfectly equipped for properly taking reference samples of used lubricating greases.

Table of contents

  1. The basic equipment
  2. Even small amounts of lubricant are sufficient!
  3. Spatula or syringe?

The basic equipment

Taking samples of lubricating greases is a bit more complicated than taking samples of liquids. However, the low-cost OELCHECK Grease Sampling Kit (Z-3) considerably simplifies this task and should be part of your basic equipment. It contains a syringe and a 20-cm tube, which can also be reordered in bulk. There are also three spatulas with different sizes for taking samples of grease located between the bearing and the seal or in the bearing cage, and a cloth for cleaning the used spatulas.

An all-inclusive analysis kit for lubricating greases from OELCHECK

Each prepaid OELCHECK all-inclusive analysis kit for lubricating greases contains:

  • A transparent sample bottle with a lid in the kit colour
  • A transparent tube for the syringe of the grease sampling kit (Z-3)
  • A specific Sample Information Form with a self-adhesive lab number for labelling the sample bottle
  • A pre-addressed, leak-tight return envelope
  • A UPS return voucher for free shipping to our laboratory

Determination of more than 20 analysis values and interpretation of these values by an OELCHECK tribologist are also included in the kit price. The clearly formulated lab report with images and individual values is usually sent by post or e-mail on the second working day after receipt of the sample. It can also be retrieved at any time from

Important: Only properly taken samples provide valid results.

  • Make sure that as much as possible, no fresh grease is included when you take the sample. The sample should come from the area where the grease does its work. You should therefore visually check, based on the change in colour or structure, that you have actually sampled used grease. Conclusions regarding the condition of the components lubricated by the grease are only possible with analysis values from used grease.
  • Please ensure that the sampling aids are clean. Before taking the sample, clean the area around the grease sampling point. Avoid contamination of the sample by dust, water or deposited seal particles
  • For trend analyses, always take the samples from a specific point using the same sampling procedure.
  • You should preferably use the aids in the OELCHECK Grease Sampling Kit. Metal particles from a screwdriver or particles from a wooden spatula can corrupt analysis values.
  • Never mix grease samples in the same sample bottle, even if they come from the same component but from different lubricating surfaces.
  • If you are not sure that we already have the grease in our database, please also send a sample of the fresh grease with your first sample of used grease for analysis, for use as a reference

Even small amounts of lubricant are sufficient!

OELCHECK needs only relatively small amounts of grease for analysis of lubricating greases. For example, only about 3 g of grease is needed for the determination of more than 30 individual values with all-inclusive analysis kit 3. That corresponds to 3 cm of grease in the tube, a bit less than a teaspoon.

Spatula or syringe?

With samples from large rolling bearings, fresh grease containers or relatively open grease sampling points, the grease can usually be sucked directly into the tube with the vacuum syringe. With less accessible components or narrow lubrication gaps, which are often also close to the seal, you will usually need to use one of the spatulas from the sampling kit.

Grease sampling with the syringe

  • Fit the tube on the conical tip of the syringe.
  • Suck up the used grease into the tube opening. Depending on the type of construction, select:
    • A drilled grease sampling hole closed by a screw
    • An inspection opening
    • A removed grease nipple or the connector for the central lubrication line.
  • Using the syringe, suck the required amount of lubricating grease into the tube. Do not allow the grease to contact the syringe. That is essential so that you can reuse the syringe.
  • Avoid sucking too much air in the grease sample!
  • Pull off the tube, fold it in the middle, and place it in the sample bottle with the fold facing up. That makes it easy to remove in the lab.

In the case of dismantled rolling bearings, you should suck the used grease into the tube from the cage area and between the rolling elements. With relatively small bearings it is better to use a spatula. With large rolling-contact bearings (over 1,000 mm), take the grease from the sampling bores provided for that purpose. The sampling points should be close to the bearing races in the main load-bearing area

Sampling with a spatula

  • Mix the grease with the spatula or by slow rotation, in order to obtain a representative sample amount.
  • As much as possible, the grease sample should be taken from the following places: the running surfaces, the web of the bearing cage, or from both sides of the bearing balls or rollers.
  • Scrape the grease from the spatula into the lid of the sample bottle or somewhere in the sample bottle, and then securely close the sample bottle.

OELCHECKER Winter 2018, page  7