A Parker Catalog 4400 hose part number is short and dense: a 3-digit series, an optional cover letter, and a dash size. Most of it reads straight off once you know the rules, but two things catch people and both cost money. The dash is a real dimension (the hose inside diameter in 1/16 inch), and the working pressure on a legacy SAE hose is not one number, it falls as the hose gets bigger.
This guide explains the part number the Parker Hydraulic Hose Decoder resolves: how to read the series, cover, and dash; the difference between a constant-pressure GlobalCore hose and a size-varying legacy series; what the TC and ST covers do; and why the matching fitting series can change with size.
How to Read a 4400 Part Number
Take 387TC-8 apart:
- 387 is the hose series, which sets the family, the spec, and the pressure class.
- TC is the cover style (ToughCover). It is optional on most series and changes the cover, not the pressure, but a few series (471, 472, 482) are sold only in TC or ST, so on those the cover is a required part of the number.
- -8 is the dash size, the hose inside diameter in 1/16 inch. So -8 is 8/16 = 1/2 inch.
A second dash, as in 471TC-6-6, marks a bonded twin line (two hoses joined side by side). The dash is the hose ID; the fittings and threads on the finished assembly have their own size boxes in the full part number, so the hose dash is not automatically the fitting dash.
GlobalCore vs Legacy: Why Pressure Changes With Size
This is the one that bites. On a legacy SAE hose (302, 422, 471, 482), the working pressure drops as the inside diameter grows. The reinforcement is sized to the hose, and a bigger bore at the same wall holds less pressure:
| 422 size | ID | Working pressure |
|---|---|---|
| 422-4 | 1/4" | 3250 psi |
| 422-8 | 1/2" | 2325 psi |
| 422-16 | 1" | 1275 psi |
| 422-32 | 2" | 575 psi |
That is a 5.6x spread on one hose. If you read the rating off the small size and apply it to the big one, you are off by thousands of psi. GlobalCore series (187, 387, 487, 722, 777, 787, 797) are the opposite: they are engineered to hold a single working pressure across the entire size range (387 is 3000 psi at every size), which is the whole point of that family. The decoder labels which behavior you are looking at on every result.
Parker Hydraulic Hose Decoder
Decode a Parker Catalog 4400 hose part number (387-8, 471TC-6, 302-16, 797-16) into hose ID, OD, the working pressure for that exact size, minimum bend radius, construction, cover, and the matching fitting series. Legacy hose pressure drops with size, so the lookup is per (series, dash).
The Cover Suffixes: TC and ST
The optional cover letter is an abrasion and temperature feature, not a pressure change:
- TC (ToughCover): a more abrasion-resistant cover, about 80 times the abrasion life of standard rubber (ISO 6945), for harsher routing.
- ST (SuperTough): the most abrasion-resistant cover, about 450 times standard, for severe rub.
A 387, a 387TC, and a 387ST are the same hose at the same 3000 psi: only the cover differs. Strip the suffix to find the base series and its pressure. One important exception to the "strip it" rule is the 722 number, which is two hoses split by size: in the small sizes, 722 and its 722TC and 722ST tough-cover versions are the GlobalCore 4000 psi constant-pressure hose; in the large sizes (-20, -24, -32), 722TC / 722ST is the SAE 100R12 four-spiral, a size-varying hose. The decoder reads the dash size to pick the right one, so 722TC-8 is the GlobalCore hose and 722TC-20 is the R12.
Fittings and Crimp: Size-Dependent
The matching fitting series is not one value for the whole hose series. On many Parker hoses the correct crimp fitting series shifts between the small and large sizes (387 uses the 43 series on the small sizes and the 77 series on the large sizes, for example). Confirm the fitting series for the exact dash you have, not just the family.
The crimp itself, the crimp diameter and the insert, is set by the Parker tooling chart (Catalog 4480-T20) for the specific hose and fitting combination. It is not something you calculate, and this decoder does not validate it: use the decode to identify the hose and fitting series, then look up the crimp spec in the Parker tooling data.
Suction and Push-Lok: Low-Pressure, Different Rules
Not every 4400 hose is a crimped pressure line:
- Suction and return (811, 881): SAE 100R4 low-pressure hose with a wire helix and a published vacuum rating. It moves fluid back to tank or feeds a pump inlet; it is not a pressure hydraulic hose.
- Push-Lok (801, 836, 821): multipurpose push-on hose that assembles onto 82-series push-on fittings with no crimping. It is low-pressure and must not be substituted for a crimped high-pressure hydraulic hose.
The decoder flags both so a low-pressure hose is never mistaken for a pressure line, and so you do not go looking for a crimp spec on a push-on hose.