Food-Grade Impregnation Oil PE1152 — 1 Litre

An oil-impregnated sintered bearing works on capillary action across its interconnected porosity. During sintering, the bronze or iron powder fuses into a rigid skeleton that retains roughly 20-25% open, interconnected pore volume, and that pore network is flooded with PE1152 under vacuum. In service, frictional heat and the hydrodynamic pressure generated in the shaft-to-bore clearance draw a thin film of oil out of the pores to the running surface: the oil's thermal expansion and the local pressure gradient bleed lubricant exactly where and when the contact needs it, so the bearing runs on a self-generated film rather than on grease or external oil feed.

When motion stops and the bush cools, capillary forces reverse the process and reclaim the oil back into the porous matrix, leaving the surface effectively dry. This continuous release-and-recovery cycle is what delivers maintenance-free, dry-running operation over long intervals. It also explains why the oil itself matters: as the charge is gradually depleted by evaporation, migration and end-of-life wear, re-impregnating with a like-for-like fluid such as PE1152 — clean, food-grade and of the correct impregnation viscosity — restores the original self-lubricating behaviour without contaminating a food-contact environment.

PE1152 charges a sintered bush by filling its open porosity, so cleanliness and full penetration are the priorities. Handle the oil and the bearings in a clean area and avoid cross-contaminating the bottle with non-food-grade lubricants — keep it sealed between uses and clearly segregated from workshop oils.

• Prepare the bush: ensure the sintered part is clean, dry and free of swarf, old degraded oil or degreaser residue before impregnation; any surface contamination blocks the pores.
• Vacuum impregnation (preferred): submerge the bushes in PE1152 and draw a vacuum to evacuate air from the pore network, then release the vacuum so atmospheric pressure forces oil deep into the interconnected porosity. This gives the most complete, repeatable charge.
• Hot-oil dip (workshop alternative): where vacuum equipment is unavailable, immerse the bushes in warmed PE1152 and hold until air bubbles cease, allowing thermal cycling to draw oil into the matrix; let parts drain and cool before fitting.
• Fitting the bush: press impregnated bushes into a clean, correctly sized housing using an arbor press and a piloted mandrel; because sintered bores can close slightly on press-fit, check running clearance after installation rather than reaming, which would smear and seal the surface pores.
• Wipe and store: remove surplus surface oil before assembly, and store both bottle and spare impregnated bushes sealed and away from dust, heat and direct sunlight to protect the charge.

Choose PE1152 whenever a sintered self-lubricating bush operates in an area where the lubricant could make incidental contact with food, beverage or ingredient streams, or where a hygienic audit requires a food-grade fluid throughout the machine — for example bottling lines, bakery equipment, meat conveyors and packaging cells. For general industrial machinery with no food-contact risk, a standard (non-food-grade) sintered-bearing impregnation oil is the more economical charge and is usually preferred. PE1152 is a food-grade impregnation oil, not a bulk lubricant: it is intended for charging and restoring porous sintered bushes and blanks (BP25 bronze, FP20 iron and similar), not as a general gear, chain or bearing-housing oil. Match the impregnation charge to the fluid the bushes were originally supplied with — a like-for-like food-grade oil such as PE1152 — rather than mixing chemistries, and select the 1-litre bottle for maintenance re-impregnation and small-batch initial charging.