Round Rod in POM H 8x1500 mm natural

A round rod in POM H is acetal in homopolymer form, which gives slightly higher stiffness, hardness and tensile strength than the matching copolymer. The density sits at 1.42 g/cm³. The continuous service temperature reaches up to 105 degrees, and the material handles down toward -50 degrees without losing its toughness. The higher crystallinity of the homopolymer also gives better creep strength under static load over time, which is worth counting in when the component is going to stand under constant pressure.

POM H is one of the most dimensionally stable engineering materials in the range. The water absorption stops around 0.85 percent, which means tolerances hold even in a damp environment and through temperature swings. The coefficient of friction against steel is low, the wear resistance high, and the fire rating is HB to UL 94. The material carries food approval in natural color from most producers, but always check the specific certificate if the part is going to end up in direct food contact.

In round rod form, POM H is used mainly where a piece of material is to be turned, milled or drilled into a finished part. Classic applications are bushings, sliding rings, shafts, sleeves, gears, cams, coupling parts and precision components in pumps and valves. In the food and packaging industry the material goes straight into conveyor parts, guide wheels and dosing mechanics where low friction and good wear resistance are decisive. In medical technology, optics and precision mechanics the ability of the material to hold its shape after machining without post curing or stabilizing is put to use.

In machining, POM H behaves roughly like brass. It can be machined at high cutting speeds, gives short chips and leaves a shiny, dimensionally accurate surface without extra finishing. Use sharp tools with a positive rake angle and apply plenty of compressed air or emulsion to blow the chips away. Keep in mind that the material expands more than steel when it is heated. Count on a length expansion of around 0.11 mm per meter per degree, and give generous tolerances on a press fit against metal. Long turned parts should be supported with a tailstock center to avoid deflection.

POM H is not glue friendly in the classic sense. Join parts with screws, snap fits or mechanical mounting, or alternatively with surface activation before gluing. Welding works with hot gas or ultrasound in series production. The material is not UV stable in natural color, so for outdoor use or long exposure in direct sunlight the black version or a protective coating is recommended. For tapping, ordinary metal taps are used; keep the cutting speed lower than in turning so the thread does not heat up.

Compared with the copolymer, POM H has slightly lower toughness under impact but higher crystallinity, which shows as higher stiffness and better dimensional stability in precision machining. That is why it is often the first choice for turned precision parts where the slightly softer behavior of the copolymer would give poorer machined surfaces. For components that take impact or are loaded dynamically over time, the copolymer (POM C) is often a better choice. The same holds for longer contact with hot water above 60 degrees, where the copolymer resists hydrolysis better.

The rod is supplied in natural color as standard, with diameters from small bushing sizes up to heavier dimensions for shaft and wheel blanks. Lengths are cut to order. Chemically the material stands up to most organic solvents, fuels, oils and weak acids. Strong acids, oxidizers and alkaline solutions with a high pH should be avoided in longer contact. Ozone, chlorine in higher concentrations and strong UV light slowly degrade the surface.

Picking the right POM grade is usually governed by what the part does. If you need maximum stiffness and a turned surface with tight tolerances, POM H is the right one. If the part has to absorb impact or work in an environment with chlorinated water, we would rather pick the copolymer. For plain bearings without external lubrication, PTFE filled or internally lubricated POM grades are a better choice than pure POM H, because friction and wear resistance in a dry running environment differ markedly. We carry both in the range and are happy to help compare.

The standard length is around one meter, and longer rods are cut down at delivery to make handling easier. For larger volumes or specific dimensions we can also bring in special sizes on request. Stocked natural colored round rods cover the breadth of common diameters for workshop use; the black version is used where UV stability or looks govern the choice. If you need help choosing a grade or a dimension for a specific component, get in touch with us with a drawing or a description of the function, and we will give you a concrete proposal for the right grade and dimension.

A thin natural rod, 8 mm in diameter and 1500 mm long, for slim pins and shafts where the hardness of the homopolymer does its job.