Equipment Manufacturers realize that money spent to protect the life of their products repays them many times in customer satisfaction and reduced service cost. That is why Hydrowype Scraper Rings are installed in thousands of military and industrial systems ranging from aircraft landing gear to precision scientific instruments. On this page you can access information about the Hydrowype Scraper Ring, including a Product Overview, Specifications, Installation instructions, Life-span information and ordering details. You can also request a quotation and provide feedback.

Manufactured by Gadjets, Inc., Hydrowype Scraper Rings ensure the maximum removal of dirt, sand, dust, ice, snow, tree-sap and other abrasive materials from a piston rod as it moves in and out of a hydraulic or pneumatic cylinder. Designed with a metal-to-metal fit and controlled breakout friction, Hydrowype Scraper Rings prevent foreign matter from cutting seals/packing, scoring rods and bearings and from the loss of hydraulic fluids and pressure.

Installers have reported that Hydrowype Scraper Rings have saved them tens and even hundreds of thousands of dollars on one installation in less than a year's time.

By keeping dirt out of your hydraulic, pneumatic and other mechanical equipment, Hydrowype Scraper rings improve the life of your equipment and the reliability of your business performance.

Just a few of the many popular Hydrowype Scraper Ring applications include aircraft landing gear, shock absorbers, power steering cylinders, lifting equipment, foundry equipment, presses, machine tools, construction, agricultural and road-building machinery.

The unique combination of materials and design features in the Hydrowype scraper ring, ensure that the scraper ring is able to perform consistently throughout it's life, limiting the ingress of potential contaminants.

The preferred brass material is sufficiently malleable so as to allow the scraper to conform entirely to the surface of the rod, while also providing an ideal combination of hardness and tensile strength which protect against the ingress of contaminants.

The 5o angle of the ID both produces a sharp cutting edge as well as inducing rotation of the ring, so continually moving the slot (scarf) and further reducing the likelihood of the ingress of contaminants.


A-Series Scraper Rings

Gadjets Hydrowype A-Series scraper rings manufactured in the company's Dayton, Ohio plant are the standard-bearer for military specification hydraulic scraper rings.

Gadjets Scrapers have been protecting rods and packing in the landing gear of military aircraft and in other government applications for six decades.

The mil-spec A-Series Scraper Rings are available in several form-factors.



Designed primarily for OEM's and maintenance/repairers engaging in a full tear-down refurbishment, one-piece Scraper rings provide the optimal ratio of tension against the rod vs. break-out friction. This is achieved by the use of a unique coiled design that pretensions the ring so that it will hold it's wiping capability over a very large number of cycles.

A patented spring is incorporated (in A20-A71) to allow the tension to be maintained throughout the life of the scraper ring.



Gadjets introduced the two-piece rings for the A-series range specifically for maintenance-repair applications including live-replacement so a full tear-down or removal of the rod-end, clevis or linkage can be avoided. The two-piece ring is especially effective when combined with the Hydrowype or some similar means of fixing the ring in place outboard of the cylinder cap and existing packing. Thus, in retrofit situations, the adapter can simply be released from the end-cap, the spring and two halves of ring removed and replaced with a new kit.

The two-piece ring takes advantage of a patented spring design, to retain the two halves of the ring after they have been fitted to the rod.



Most usually, a Hydrowype scraper ring is intended to scrape the external surface (outside diameter) of a rod. Thus, the ring is constructed using a process that allows for the precision scraping edge to be cut into the inside diameter of the ring as the final step of manufacture, which is completed immediately prior to shipping.



Scrapers that are constructed to provide a precision scraping edge on the outside diameter of the ring are also available in the Hydro-Wype product family, for use in applications where a bore or cylinder interior needs to be maintained free of contaminants.



Gadjets Inc. has recently introduced the new AB-Series of premium metal scrapers designed specifically for commercial applications. Manufactured in brass, with a stainless steel spring, the AB range includes both the original one-piece, and newer two-piece metal ring designs. The primary difference between the new AB range and previous versions of the Hydrowype scraper, is that the AB series are unplated.

Cadmium, or other mil-spec plating is often unnecessary in many commercial environments as brass and other available copper alloys provide sufficient corrosion resistance, the AB-series can be provided as a more economical and readily available alternative.



Hydro-Wype Scraper Rings:

have a scraping edge free from nicks and burrs, and must have a surface finish of 50 micro inches R.M.S. or better and be treated to prevent corrosion.


are made of copper based alloys, and have no internal strains or cracks when subjected to the mercurous nitrate and nitric acid test. Hydrowype Scraper Rings are designed to absorb all the abuses and impacts that it may be subjected to in the initial shock of a landing gear or the reversing stroke of an accumulator cylinder piston rod.


are required to fit a ground piston rod 95% light tight at all times. Extensive tests prove that they exceed this requirement, and that less than 1/2 of 1% of the circumference of the piston rod is exposed to dirt, grit or ice. Due to the rotary action of the Hydrowype Scraper Ring, the exposed area is never in the same place.


because of their design and closely controlled dimensions, will remove all types of frozen accumulations whether it be oil, frost, mud or ice from the piston rod.

Controlled breakout friction of Hydrowype A Scraper Rings is possible due to the pre-stressed design which applies tension equally about the circumference of the Rings, and prevents excessive pressure tending to load the piston rod causing accelerated wear, friction and heat.

Scraper Rings are constantly checked in production to provide the maximum life. Samples are tested for breakout friction by abrasion and cycled 50,000 four inch strokes on a ground mandrel, DRY with no lubrication, and then stretched .010 of an inch oversize. After these grueling tests, Hydrowype Scraper Rings must still be 95% light tight to ensure that you get the protection you pay for. Our customers have reported that after 10,000,000 cycles, Hydrowype A's are still giving 99.5% protection to their products.

Hydrowype A-Series and AB-SeriesScraper Rings can be used over a wide range of temperatures from -65o to +500oF. Due to the pre-stressed tensioners, the Hydrowype Scraper Ring will compensate, not only for expansion and contraction due to temperature, but also for any wear that may result both in the Scraper Ring and/or on the piston rod.

The Hydrowype family of scraper rings use proprietary, flat, pre-stressed tensioners for ring sizes A1 through and including A15. A continuous stainless steel pre-stressed tensioner as indicated, is used on Hydrowype Scraper Rings, sizes A16 through and including sizes A71, and special sizes up to and beyond 36" inside diameter.

Tensioners are a particularly important aspect of the design of the Hydrowype. They ensure the correct ratio of circumferential pressure, to breakout friction. In this manner, the tension helps prevent the ingress of any potential contaminant, while also ensuring that breakout friction does not become excessive.